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  • 151.
    Panasiuk, Joanna
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Kowalczuk, Lukasz
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    ON BITSTREAM FEATURES BASED PERCEPTUAL QUALITY ESTIMATION OF HEVC CODED VIDEOS2015Independent thesis Advanced level (degree of Master (Two Years))Oppgave
    Abstract [en]

    ABSTRACT Context: High Efficiency Video Coding (HEVC) is a new video coding standard which combines high video quality with higher compression ratios. In order to fully use the potential of this standard, there should be created an appropriate coding tool (coder), which determines proper coding parameters to ensure the highest possible video quality while maintaining a specified bitrate. Objectives: This thesis aims at proposing a set of bitstream based features that can be used for perceptual quality estimation of HEVC encoded videos. To this purpose, we develop required computer programs capable of extracting these features from coded video files. The extracted features are used in an artificial neural network (ANN) based model to estimate video quality. Methods: To conduct our solution, we performed a profound analysis of the HEVC coding standard, and then we designed software that precisely retrieves all needed data from video files. The software was created in C# language in order to allow for the analysis of big sized XML files. The other programs were created in Matlab software. They contain file converters and ANN video quality predictor which perform prediction of quality values on the basis of extracted parameters values. Tests were performed on 560 sample video files. Results: ANN provided very good results in quality prediction. All experiments showed that for all tested quality metrics presents very good fit. The highest correlation coefficient R is for VIFP quality metric and is averagely equal to R= 0,992. Conclusions: Summarizing presented approach for extraction video parameters and quality prediction can be implemented in real experiments. Provided testing conditions allow to achieve for satisfying results.

  • 152.
    Pandremmenou, Katerina
    et al.
    Univ Ioannina, Dept Comp Sci & Engn, GR-45110 Ioannina, Greece..
    Shahid, Muhammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Kondi, Lisimachos P.
    Univ Ioannina, Dept Comp Sci & Engn, GR-45110 Ioannina, Greece..
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    ON THE IMPROVEMENT OF NO-REFERENCE MEAN OPINION SCORE ESTIMATION ACCURACY BY FOLLOWING A FRAME-LEVEL REGRESSION APPROACH2015Inngår i: 2015 IEEE INTERNATIONAL CONFERENCE ON IMAGE PROCESSING (ICIP), 2015, s. 1850-1854Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In order to estimate subjective video quality, we usually deal with a large number of features and a small sample set. Applying regression on complex datasets may lead to imprecise solutions due to possibly irrelevant or noisy features as well as the effect of overfitting. In this work, we propose a No-Reference (NR) method for the estimation of the quality of videos that are impaired by both compression artifacts and packet losses. Particularly, in an effort to establish a robust regression model that generalizes well to unknown data and to increase Mean Opinion Score (MOS) estimation accuracy, we propose a frame-level MOS estimation approach, where the MOS estimate of a sequence is obtained by averaging the perframe MOS estimates, instead of performing regression directly at the sequence-level. Since it is impractical to obtain the actual perframe MOS values through subjective experiments, we propose an objective metric able to do this task. Thus, our proposed NR method has the dual benefit of offering improved sequence-level MOS estimation accuracy, while giving an indication of the relative quality of each individual video frame.

  • 153. Pandremmenou, Katerina
    et al.
    Shahid, Muhammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Kondi, L.P.
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    A No-Reference Bitstream-based Perceptual Model for Video Quality Estimation of Videos Affected by Coding Artifacts and Packet Losses2015Inngår i: Proceedings of SPIE - The International Society for Optical Engineering, San Francisco: SPIE Press , 2015, Vol. 9394, s. Article number 93941F-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this work, we propose a No-Reference (NR) bitstream-based model for predicting the quality of H.264/AVC video sequences, a effected by both compression artifacts and transmission impairments. The concept of the article is based on a feature extraction procedure, where a large number of features are calculated from the impaired bitstream. Many of the features are mostly proposed in this work, while the specific c set of the features as a whole is applied for the first time for making NR video quality predictions. All feature observations are taken as input to the Least Absolute Shrinkage and Selection Operator (LASSO) regression method. LASSO indicates the most important features, and using only them, it is able to estimate the Mean Opinion Score (MOS) with high accuracy. Indicatively, we point out that only 13 features are able to produce a Pearson Correlation Coefficient of 0:92 with the MOS. Interestingly, the performance statistics we computed in order to assess our method for predicting the Structural Similarity Index and the Video Quality Metric are equally good. Thus, the obtained experimental results verifi ed the suitability of the features selected by LASSO as well as the ability of LASSO in making accurate predictions through sparse modeling.

  • 154.
    Parthasarathy, Sindhu
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling. Automatic Control and Robotics .
    Autonomous Sensor System for Self-Monitoring of Training in Shooting Sport2017Independent thesis Advanced level (degree of Master (Two Years)), 80 poäng / 120 hpOppgave
    Abstract [en]

    The factor of precision has always been the mastermind of the shooting sport. With new shooters coming into the field every day and with more aspiring shooters bringing laurels, a help of technology for training can make a difference. When advanced systems like the SCATT, Electronic Target Systems, etc. are marked for the people of the higher background, an easy handle autonomous system for self-monitoring training of precision improvement has always been a question of far reach. This project is about developing an external removable device, which will monitor and evaluate the shooter efficiency of gripping weapon, measure by pressure given at the contact points of the weapon.

    In the contact points, such as the trigger, the hand grip, cheek rest, butt plate and the hand rest; we use force sensitive resistors, which are connected to an automatic monitoring system built over an Arduino platform. The system analyses the shots based on the variation in the pressure at each point of contact for every shot. By further analysis and consolidation, the average pressure over a range of shots, an optimal pressure point can be fixed individually for the respective shooter. This pressure points are used as references, by rating them in comparison with the corresponding shot acquired in the target. The system includes a pre-designed training program, which autonomously monitors and trains the shooter to achieve the optimum grip in every shot, thereby increasing the accuracy and precision in a sequence of shots. With time, it helps the body to develop a muscle memory based on controlled training and learn the rhythm of applying optimum pressure to achieve better results.

  • 155.
    Poreddy, Mahathi
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Outage Probability Analysis of CooperativeCognitive Radio Networks Over κ − μ Shadowed Fading Channels2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Over time, wireless technology advancements in the field of communications have been attracting every individual to turn into a wireless user. To accommodate the increasing number of users and to avoid the problem of spectrum scarcity, the concept of Cognitive Radio Network (CRN) has been developed. Cognitive Radio (CR) is an intelligent radio which efficiently detects and allocates the spectrums of primary licensed users (PUs) to the secondary unlicensed users (SUs). The SUs can utilize these spectrums as long as they do not cause harmful interfere to the PUs. Interference may occur because of the following reasons: misdetection of spectrum availability, the high transmission power of SU when both SU and PU are present in the same channel at the same time. In order to avoid interference, the radio has to have a very accurate spectrum sensing method, transmit power at SU should be constrained by the peak interference power of PU and the CR should continuously sense the presence of PUs. To increase the wireless coverage area and reliability of CRN, a new technology called Cooperative Cognitive Radio Network (CCRN), which is a combination of CRN and cooperative communications was developed. A CCRN not only increases the reliability and wireless coverage area of CR but also improves the overall performance of the system.

    In this context, the main objective of this research work is to evaluate the outage performance of a CCRN in an environment where fading and shadowing also come into the picture and to study the importance of relay networks in CRN.

    To fulfill the objectives of this research work, a two-hop decode-and-forward CCRN is considered. The recently introduced κ − µ shadowed fading channel is employed over the CCRN to generate a realistic environment.  In order to implement such system as a whole, a deep literature study is performed beforehand.

    Analytical expressions for the Probability Density Function (PDF) and Cumulative Distribution Function (CDF) of the Signal-to-Noise Ratio (SNR) are obtained. The analytical expressions and simulation results for Outage Probability (OP) are obtained and compared under different fading parameters. The importance of a multiple-relay system in CRN is presented.

    From the results obtained in this research work, we can conclude that the OP decreases with increase in allowable peak interference power at the PU. The transmit power at SU should always be constrained by the peak interference power at the PU to avoid interference. The overall system performance increases with increasing number of relays.

  • 156.
    Prasanna Bhubalan, Suriya
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Dziadak, Damian
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Autonomous Filming of Test Cars: Application integration and autonomous control approach2016Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Before vehicles that go to sale for public it goes through many stages of testing in different fields. All types of pre-production cars are the vehicles that come after prototypes which allow the OEM to find out possible issues by running different categories of tests. One of the most important fields of test is regarding safety. When it comes to autonomous cars, where safety is crucial, the number of tests to carry out, time for handling them and their complexity is increased. To reduce costs, complexity and time some of them might be simulated. After the analysis is done the cars have to be tested in real time to collect more data, not only from car sensors but also through observation from the tests filmed. This thesis contains an overview of whole project leading to develop an autonomous platform, driving after autonomous car and controlled by simulation environment and solving major issues of the project.

    The filming of autonomous cars remotely had two major issues. One of the issues was to integrate all the different software and platforms. The trajectories of the autonomous cars were controlled in different software and the trajectories of the RC were managed in different software. The solution to integrate all the software and platforms is shown in this thesis.

    The second issue was to make the RC car to follow the waypoints that are generated by simulation and by communicating with real car using a PID controller. The project is prepared for future improvements, like installing a camera to the RC car which will follow predefined test independently.

  • 157.
    Premachandran, Rammohan
    et al.
    Atlas Copco.
    Håkansson, Lars
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    SIGNAL ANALYSIS FOR PERFORMANCE MONITORINGOF DRILLING WITH DOWN THE HOLE (DTH) ROCK DRILLS2015Inngår i: PROCEEDINGS OF THE 22ND INTERNATIONAL CONGRESS ON SOUND AND VIBRATION: MAJOR CHALLENGES IN ACOUSTICS, NOISE AND VIBRATION RESEARCH, 2015, INT INST ACOUSTICS & VIBRATION , 2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Today rock drilling operations mainly relies on the experience of the operators. Expe-rienced drillers observes the sound produced by the drilling machinery and in general, base their judgments on their intuition. An efficient drill monitoring system, providing reliable and robust in-formation on the performance of the drilling process, is likely to provide experienced drillers with additional information, to further improve the drilling process. Such a system is also likely to provide guidance to inexperienced drillers to improve their drilling performance concerning quality and efficiency. To enable monitoring of drilling performance in down the hole (DTH) rock drilling, simultaneous measurements of vibrations, with the aid of accelerometers mounted at specific locations on the drill rig, and other quantities such as different line pressures controlling different movements of the drill string are considered in combination with suit-able signal processing methods. A number of properties, e.g. spectral properties, of the vibration sig-nals and the pressure line signals under good drilling and bad drilling conditions are compared. Both the vibration and pressure signals display distinguishable properties between the case of "good" drill-ing and the case of "bad" drilling.

  • 158.
    Premachandran, Rammohan Kodakadath
    et al.
    Atlas Copco, SWE.
    Håkansson, Lars
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Comparison of spectral properties of the vibration signals and line pressure signals of DTH drills2016Inngår i: ICSV 2016 - 23rd International Congress on Sound and Vibration: From Ancient to Modern Acoustics, International Institute of Acoustics and Vibrations , 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Quantifying and Monitoring of drilling performance are becoming exceedingly important in the case of Down the Hole drilling. Various economic, environmental and safety constraints are driving the drilling process to become more efficient. To make a robust system that would enable the performance/condition monitoring of the drilling, we must understand how different properties like different line pressure etc. respond to various drilling conditions and what information can they provide regarding the Drilling Performance. A comparison of different properties like spectral properties, of the vibration signals and Pressure signals under known conditions would enable better understanding of the drilling system and the physics behind the process. A comparison is made between the Spectral properties of the vibrational signals obtained from remote locations on the drill rig and pressure signals that provide the feed and holdback forces to the drill string and a correlation between their characteristics and patterns under good and bad drilling conditions have been made. A simplified model of the system is simulated and results are compared with the patterns obtained from analyzing the Vibration signals.

  • 159.
    Purkayastha, Pratik
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Diagnostics and Prognostics of safety critical systems using machine learning, time and frequency domain analysis2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The prime focus of this thesis was to develop a robust Prognostic and Diagnostic Health Management module (PDHM), capable of detecting faults, classifying faults, fault progression tracking and estimating time to failure. Priority was to obtain as much accuracy as possible with the bare minimum amount of sensors as possible. Algorithms like k-Nearest Neighbors (k-NN), Linear and Non- Linear regression and development of rule engine to identify safe operating limits were deployed. The entire solution was developed using R (v 3.5.0). The accuracy of around 98% was obtained in diagnostics. For Prognostics, our ability to predict time to failure more accurately increases with time. Some balance must be there between learning horizon and predicting horizon in order to get good predictions with reasonable time left to hit catastrophic failure. In conclusion, the PDHM module works just as desired and makes Predictive maintenance, smart replacement and crisis prediction possible ensuring the safety and security of people on board and assets.

  • 160.
    Qi, Hongye
    et al.
    Southeast Univ, State Key Lab Millimeter Waves, Nanjing 210096, Jiangsu, Peoples R China..
    Liu, Leilei
    Nanjing Univ Posts & Telecommun, Nanjing 210093, Jiangsu, Peoples R China..
    Yin, Xiaoxing
    Southeast Univ, State Key Lab Millimeter Waves, Nanjing 210096, Jiangsu, Peoples R China..
    Zhao, Hongxin
    Southeast Univ, State Key Lab Millimeter Waves, Nanjing 210096, Jiangsu, Peoples R China..
    Kulesza, Wlodek
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Mutual Coupling Suppression Between Two Closely Spaced Microstrip Antennas With an Asymmetrical Coplanar Strip Wall2016Inngår i: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 15, s. 191-194Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This letter describes an asymmetrical coplanar strip (ACPS) wall to suppress the mutual coupling between two closely spaced 5.8-GHz microstrip antennas. The ACPS wall, which is inserted vertically between the two antennas, introduces an additional coupling path to reduce the antenna coupling, occupying just a small area between the two antennas. The decoupling effect of the proposed structure is verified by the simulation and measurement. The experimental results show that the achieved isolation is better than 35 dB and reaches a maximum of 54.3 dB at 5.8 GHz, with an extremely close antenna distance of 0.03 lambda(0) (edge-to-edge distance). The measured patterns indicate that the proposed structure also improves the radiation of the microstrip antenna.

  • 161.
    R V Krishnam Raju, Kunadha Raju
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Perceptual Image Quality Prediction Using Region of Interest Based Reduced Reference Metrics Over Wireless Channel2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    As there is a rapid growth in the field of wireless communications, the demand for various multimedia services is also increasing. The data that is being transmitted suffers from distortions through source encoding and transmission over errorprone channels. Due to these errors, the quality of the content is degraded. There is a need for service providers to provide certain Quality of Experience (QoE) to the end user. Several methods are being developed by network providers for better QoE.The human tendency mainly focuses on distortions in the Region of Interest(ROI) which are perceived to be more annoying compared to the Background(BG). With this as a base, the main aim of this thesis is to get an accurate prediction quality metric to measure the quality of the image over ROI and the BG independently. Reduced Reference Image Quality Assessment (RRIQA), a reduced reference image quality assessment metric, is chosen for this purpose. In this method, only partial information about the reference image is available to assess the quality. The quality metric is measured independently over ROI and BG. Finally the metric estimated over ROI and BG are pooled together to get aROI aware metric to predict the Mean Opinion Score (MOS) of the image.In this thesis, an ROI aware quality metric is used to measure the quality of distorted images that are generated using a wireless channel. The MOS of distorted images are obtained. Finally, the obtained MOS are validated with the MOS obtained from a database [1].It is observed that the proposed image quality assessment method provides better results compared to the traditional approach. It also gives a better performance over a wide variety of distortions. The obtained results show that the impairments in ROI are perceived to be more annoying when compared to the BG.

  • 162.
    Rakk, Adrian
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Automatically measuring the resistive loss of a transformer: A project in cooperation with Alstom Power Sweden2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    In order to develop more economical and ecologically friendly transformers it is necessary to know the losses throughout the product development process. There are several losses related to transformers, but in this particular case the focus will be on the resistive loss of the transformer. In order to measure this loss first the resonant frequency of the transformer is determined. Since at resonance the secondary side of the transformer is considered to be purely resistive. The aim of this paper is to design and build a closed loop measurement system that is able to perform this task.

  • 163.
    RAMANCHA, BHARAT REDDY
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Performance Analysis Of No-reference Video Quality Assessment Methods For Frame Freeze and Frame Drop Detection2014Independent thesis Advanced level (degree of Master (Two Years))Oppgave
    Abstract [en]

    Data transmission through a network has become a challenging task considering the loss of data factor. This is similar in the case of video transmission through a network. Error prone channels present in the network are responsible for the quality degradation of decoded video. There must be some metric monitoring the quality of this decoded video. Lot of research work is done in this field and many metrics are designed for video quality estimation considering various factors. Most of the metrics are designed considering only few factors thereby limiting their scope for few videos. In this research we investigate few metrics and propose the best metric by implementing them on different videos. Best metric proposed gives the video quality estimation independent of resolution and artifact in a video. Subjective analysis is conducted for validation of our results. Metrics that are implemented belong to NO-REFERENCE video quality metric group.

  • 164.
    Rao, Peddi Srinivas
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Sreelatha, Vallabhaneni
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Implementation and Evaluation of Spectral Subtraction with Minimum Statistics using WOLA and FFT Modulated Filter Banks2014Independent thesis Advanced level (degree of Master (Two Years))Oppgave
    Abstract [en]

    In communication system environment speech signal is corrupted due to presence of additive acoustic noise, so with this distortion the effective communication is degraded in terms of the quality and intelligibility of speech. Now present research is going how effectively acoustic noise can be eliminated without affecting the original speech quality, this tends to be our challenging in this current research thesis work. Here this work proposes multi-tiered detection method that is based on time-frequency analysis (i.e. filter banks concept) of the noisy speech signals, by using standard speech enhancement method based on the proven spectral subtraction, for single channel speech data and for a wide range of noise types at various noise levels. There were various variants have been introduced to standard spectral subtraction proposed by S.F.Boll. In this thesis we designed and implemented a novel approach of Spectral Subtraction based on Minimum Statistics [MinSSS]. This means that the power spectrum of the non-stationary noise signal is estimated by finding the minimum values of a smoothed power spectrum of the noisy speech signal and thus circumvents the speech activity detection problem. This approach is also capable of dealing with non-stationary noise signals. In order to analyze the system in time frequency domain, we have implemented two different filter bank approaches such as Weighted OverLap Added (WOLA) and Fast Fourier Transform Modulated (FFTMod). The proposed systems were implemented and evaluated offline using simulation tool Matlab and then validated their performances based on the objective quality measures such as Signal to Noise Ratio Improvement (SNRI) and Perceptual Evaluation Speech Quality (PESQ) measure. The systems were tested with a pure speech combination of male and female sampled at 8 kHz, these signals were corrupted with various kinds of noises at different noise power levels. The MinSSS algorithm implemented using FFTMod filter bank approach outperforms when compared the WOLA filter bank approach.

  • 165.
    Rossholm, Andreas
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    On Enhancement and Quality Assessment of Audio and Video in Communication Systems2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The use of audio and video communication has increased exponentially over the last decade and has gone from speech over GSM to HD resolution video conference between continents on mobile devices. As the use becomes more widespread the interest in delivering high quality media increases even on devices with limited resources. This includes both development and enhancement of the communication chain but also the topic of objective measurements of the perceived quality. The focus of this thesis work has been to perform enhancement within speech encoding and video decoding, to measure influence factors of audio and video performance, and to build methods to predict the perceived video quality. The audio enhancement part of this thesis addresses the well known problem in the GSM system with an interfering signal generated by the switching nature of TDMA cellular telephony. Two different solutions are given to suppress such interference internally in the mobile handset. The first method involves the use of subtractive noise cancellation employing correlators, the second uses a structure of IIR notch filters. Both solutions use control algorithms based on the state of the communication between the mobile handset and the base station. The video enhancement part presents two post-filters. These two filters are designed to improve visual quality of highly compressed video streams from standard, block-based video codecs by combating both blocking and ringing artifacts. The second post-filter also performs sharpening. The third part addresses the problem of measuring audio and video delay as well as skewness between these, also known as synchronization. This method is a black box technique which enables it to be applied on any audiovisual application, proprietary as well as open standards, and can be run on any platform and over any network connectivity. The last part addresses no-reference (NR) bitstream video quality prediction using features extracted from the coded video stream. Several methods have been used and evaluated: Multiple Linear Regression (MLR), Artificial Neural Network (ANN), and Least Square Support Vector Machines (LS-SVM), showing high correlation with both MOS and objective video assessment methods as PSNR and PEVQ. The impact from temporal, spatial and quantization variations on perceptual video quality has also been addressed, together with the trade off between these, and for this purpose a set of locally conducted subjective experiments were performed.

  • 166.
    Rossholm, Andreas
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    A robust method for estimating synchronization and delay of audio and video for communication services2016Inngår i: Multimedia tools and applications, ISSN 1380-7501, E-ISSN 1573-7721, Vol. 75, nr 1, s. 527-545Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    One of the main contributions to the quality of experience in streaming services or in two-way communication of audio and video applications is synchronization. This has been shown in several studies and experiments but methods to measure synchronization are less frequent, especially for situations without internal access to the application and independent of platform and device. In this paper we present a method for measuring synchronization skewness as well as delay for audio and video. The solution incorporates audio and video reference streams, where audio and video frames are marked with frame numbers which are decoded on the receiver side to enable calculation of synchronization and delay. The method has been verified in a two-way communication application in a transparent network with and without inserting known delays, as well as in a network with 5 and 10 % packet loss levels. The method can be used for both streaming and two-way communication services, both with and without access to the internal structures, and enables measurements of applications running on e.g. smartphones, tablets, and laptops under various conditions.

  • 167.
    Rossholm, Andreas
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Shahid, Muhammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Analysis of the impact of temporal, spatial, and quantization variations on perceptual video quality2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The growing consumer interest in video communication has increased the users' awareness in the visual quality of the delivered media. This in turn increases, at the service provider end, the need for intelligent methodologies of optimal techniques for adapting to varying network conditions. Recent studies show that constraints on the bandwidth of transmission media should not always be translated to an increase in compression ratio to lower the bitrate of the video. Instead, a suitable option for adaptive streaming is to scale down the video temporally or spatially before encoding to maintain a desirable level of perceptual quality, while the viewing resolution is constant. Most of the existing studies to examine these scenarios are either limited to low resolution videos or lack in provisioning of subjective assessment of quality. We present here the results of our campaign of subjective quality assessment experiments done on a range of spatial and temporal resolutions, up to VGA and 30 frames per second respectively, under a number of bitrate conditions. The analysis shows, among other things, that keeping the spatial resolution is perceptually preferred among the three parameters that have impact on the video quality, even in the case with high temporal activity.

  • 168.
    Saif, Khalid
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Alsmadi, Nazem
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Mobile Phone Antenna Design2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This thesis focuses on mobile phones antenna design with brief description about the historical development, basic parameters and the types of antennas which are used in mobile phones. Mobile phones antenna design section consists of two proposed PIFA antennas. The first design concerns a single band antenna with resonant frequency at GPS frequency (1.575GHz). The first model is designed with main consideration that is to have the lower possible PIFA single band dimensions with reasonable return loss (S11) and the efficiencies. Second design concerns in a wideband PIFA antenna which cover the range from 1800MHz to 2600MHz. This range covers certain important bands: GSM (1800MHz & 1900MHz), UMTS (2100MHz), Bluetooth & Wi-Fi (2.4GHz) and LTE system (2.3GHz, 2.5GHz, and 2.6GHz). The wideband PIFA design is achieved by using slotted ground plane technique. The simulations for both models are performed in COMSOL Multiphysics. 

    The last two parts of the thesis present the problems of mobile phones antenna. Starting with Specific absorption rate (SAR) problem, efficiency of Mobile phones antenna, and hand-held environment.

  • 169.
    SAIF, SALMAN
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    ALAM, MD. FARUQUL
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    ALI, HAMID
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    SHORT CIRCUIT CURRENT CALCULATION AND PREVENTION IN HIGH VOLTAGE POWER NETS2014Oppgave
    Abstract [en]

    This thesis is about calculating the short-circuit current on an overhead high voltage transmission line. The intention is to provide engineers and technicians with a better understanding of the risks and solutions associated with power transmission systems and its electrical installations. Two methods (“Impedance method” and “Composition method”) have been described to facilitate with the computation of the short-circuit current. Results yielded from these calculations help network administrators to select the appropriate protective devices to design a secured system. Description and implementation of these protective devices are explained and the procedure on how to ensure reliability and stability of the power system is shown. The “Composition method” deals with the concept of “short-circuit power”. Short-circuit power is the largest possible value of power that the network can provide during a fault, it is totally depended on the impedance of the components and also how the components are setup in the network. In reality this method is more useful because the value of the short-circuit power at the point pole is provided by the suppliers and this value is considered to be the total short-circuit power at that point, which also takes into account the impedance of the entire power net. When short-circuit occurs in a point along the transmission line, first the short-circuit power at that point is calculated and then the short-circuit current is calculated by using a simple formula. The short-circuit power at the point of the fault is calculated by calculating the total impedance at that point from the point pole (including the impedance of the point pole). From the impedance the short-circuit power is easily calculated. To protect the system from short-circuit current an experiment was conducted to detect the short circuit current and then prevent it from flowing through the transmission line. This was achieved by using the SPAA 120 C Feeder protection relay. The feeder protection relay triggers a magnetic switch to open the circuit if it senses a current higher than the set value. The mathematical part of this thesis work teaches how to calculate the short-circuit current in a transmission line in two different ways using two different methods. The result from the experiment teaches how to install the protective device (SPAA 120 C) to create a secured system. The main objective is to be able to determine the maximum short-circuit current of any transmission line and to be able to transfer power in a safe manner by using the SPAA 120 C feeder protection relay.

  • 170.
    Salah, Razwan Mohmed
    et al.
    University of Algarve, PRT.
    Alves, Gustavo
    Polytechnic of Porto, PRT.
    Guerreiro, Pedro
    University of Algarve, PRT.
    Gustavsson, Ingvar
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Using UML models to describe the VISIR system2016Inngår i: International Journal of Online Engineering, ISSN 1868-1646, E-ISSN 1861-2121, Vol. 12, nr 6, s. 34-42Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Analysis and design are important phases in the system development lifecycle. In these phases, developers record information necessary for properly understanding the nature of the systems under consideration. We consider a particular type of system, named Remote Lab that allows both teachers and students to perform real experiments over the internet and we focus on Virtual Instrument Systems in Reality (VISIR). We describe a summarized web interface of VISIR using the Unified Modeling Language (UML). Our case study aims at identifying the requirements of VISIR and at creating a set of UML diagrams that succinctly provide enough information to both developers and users so that they acquire enough information for building a general understanding of it. Additionally, we provide elements for extending UML to better support further user interface development in VISIR.

  • 171.
    Salah, Razwan Mohmed
    et al.
    Univ Algarve, IRQ.
    Alves, Gustavo R.
    Polytech Porto, PRT.
    Abdulazeez, Dezheen Hussein
    Univ Algarve, PRT.
    Guerreiro, Pedro
    Univ Duhok, DIRQ.
    Gustavsson, Ingvar
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    WHY VISIR?: PROLIFERATIVE ACTIVITIES AND COLLABORATIVE WORK OF VISIR SYSTEM2015Inngår i: EDULEARN15: 7TH INTERNATIONAL CONFERENCE ON EDUCATION AND NEW LEARNING TECHNOLOGIES / [ed] GomezChova, L LopezMartinez, A CandelTorres, I, IATED-INT ASSOC TECHNOLOGY EDUCATION A& DEVELOPMENT , 2015, s. 3824-3835Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Online laboratories have been increasingly deployed in several universities and institutions around the world. Besides helping to leverage a number of educational developments, they enable teachers and researchers to share their knowledge across institutional boundaries. It has been observed that online laboratories have a positive effect on students' skills acquisition because they promote collaborative work and allow students to perform physical experiments remotely usually 24/7. Today, one can find a wide range of online laboratories in the literature that are supporting many subjects in different engineering and sciences fields, especially in electric and electronic engineering. One such system is VISIR (Virtual Instrument Systems in Reality). VISIR plays an important role in electrical and electronic engineering education by allowing both teachers and students to conduct real experiments with electric and electronic circuits, via the Internet. It also complements hands-on laboratories by serving thousands of students globally, as a result of being spread by several universities and institutes worldwide. Presently, VISIR is installed in eight higher education institutions, in six different countries (Austria, Sweden, Spain, Portugal, India, and Georgia), and is the first remote lab in the world supporting a MOOC (Massive Open Online Course). In addition, a number of experiments in VISIR can be freely accessed, using the guest user mode, depending on the institutions available resources. In this study, we have used the data collection method focused on all scholarly papers that are related to the VISIR system, which allowed collecting references from many resources such as conference proceedings, book chapters, and journals. The objective of the paper is to illustrate the research activities, developments, and studies that contributed to making of VISIR the best remote controlled laboratory in the world, according to the GOLC (Global Online Laboratory Consortium). Our research included the following dimensions: a) courses and subjects that include experiments done in VISIR, from different universities and institutes; b) the number of scholarly papers and authors related to VISIR, with a reference to the publishing sources; c) the different technologies used to deliver the laboratory experiments; d) the total number (and its evolution) of users who have accessed the several VISIR nodes; e) finally, the collaborative work resulting from the use and share of the VISIR system. To conclude, the paper discusses the impact of VISIR in the role of the laboratory in undergraduate engineering education, in particular in electrical and electronic engineering, and its contribution to the collaborative work observed among the academic staff, researchers and students who used it.

  • 172.
    Salah, Razwan Mohmed
    et al.
    Univ Algarve, IRQ.
    Alves, Gustavo R.
    Polytech Porto, PRT.
    Datkiewicz, Beata
    Poznan Univ Tech, POL.
    Guerreiro, Pedro
    Univ Algarve, PRT.
    Gustavsson, Ingvar
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    VISIR SYSTEM @ BTH, DEUSTO, ISEP, AND UNED INSTITUTES: ASSISTING AND SUPPORTING HANDS-ON LABORATORIES TO SERVE HIGHER EDUCATION STUDENTS2015Inngår i: ICERI2015: 8TH INTERNATIONAL CONFERENCE OF EDUCATION, RESEARCH AND INNOVATION / [ed] Chova, LG Martinez, AL Torres, IC, IATED-INT ASSOC TECHNOLOGY EDUCATION A& DEVELOPMENT , 2015, s. 2535-2547Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Practical study is considered a backbone of qualification in engineering and sciences education. It aids understanding of the theoretical concepts for university students. Over the last decades, a limitation in available labs has become one of the encumbrances for several universities and institutions because of the cost and unavailability of instructors. It has led to decline in the students' qualifications in experimentation in engineering and sciences fields. Today, several ideas have implemented to get over the limitations of a lab, for example online labs technology, which are also referred to as, "Remote and Virtual Labs". This technology is become available over Internet, for instance Virtual Instrument Systems in Reality (VISIR). In addition, online labs prove that they can assist hands-on laboratories and may become the best technology for supporting hands-on one, regarding its low cost and ubiquity. This paper presents the number of students (access and users access) who are involved in using VISIR nodes that located at BTH, Deusto, ISEP, and UNED institutions. The filtration that used in this study is to categorize yearly and monthly access of students from those VISIR nodes.

  • 173.
    Salih, Sami H O
    et al.
    Sudan University of Science and Technology, SDN.
    Erman, Maria
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Mohammed, Abbas
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    A Novel Spectrum Sensing Scheduling Algorithm for Cognitive Radio Networks2012Inngår i: Self-Organization and Green Applications in Cognitive Radio Networks / [ed] Al-Dulaimi, Anwer; Cosmas, John; Mohammed, Abbas, IGI Global , 2012, s. 136-153Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 174.
    Schenkman, Bo
    et al.
    KTH, SWE.
    Gidla, Vijay Kiran
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Human echolocation in different situations and rooms: Threshold values Architectural Acoustics: Paper 1aAAa12017Inngår i: Proceedings of Meetings on Acoustics, Acoustical Society of America , 2017, nr 1Konferansepaper (Fagfellevurdert)
    Abstract [en]

    People, especially when blind, use echolocation to detect obstacles, orient themselves and get an awareness of their environment. Echolocation describes how people use reflected sounds to obtain information about their ambient world. Echolocation with long canes while walking is possible but difficult. Different spectral composition of the emitted sounds from canes had no differential effects. Sound recordings in anechoic and conference rooms from non-walking, static situations, later presented in a laboratory showed a better performance in an ordinary room with reflections, than in an anechoic room. Longer sounding sounds resulted in a higher performance than short clicks. Among the difficulties for the blind are how to avoid masking of sounds. There may exist a time gap, acoustic gaze, for how blind people use clicks. The results of previous studies were reanalyzed by using auditory models. Thresholds based on local non-parametric fitting, were determined for distance, pitch, loudness and sharpness. The blind had overall a more sensitive threshold than sighted persons. A few blind are exceptionally high performing. An information-surplus principle' has been proposed. Various information sources are used, but repetition pitch seems more important than loudness for echolocation. Among other sources, timbre may also provide information. © 2017 Acoustical Society of America.

  • 175.
    Selvaraj, Vevek
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Evaluation of measurement data for an optical free-space aircraft to ground communication link system2014Independent thesis Advanced level (degree of Master (Two Years))Oppgave
    Abstract [en]

    Optical free-space communication is an e ffective approach that can provide tap-proof, high bandwidth data communications. In this thesis there is an Optical link established between aircraft and the ground station. The link created between aircraft and ground station will go through the wavefront distortions due to the atmospheric turbulence,hence the signal quality is degraded. In order to optimise system performance the impact of atmospheric eff ects have to be evaluated for di fferent light conditions and link distances. To compensate the wavefront distortions Adaptive Optics can be used. In this thesis the main aim is to process the measured data from di fferent optical sensors in order to extract amplitude and phase information of the received field. The downlink data from the aircraft to the optical ground station that are obtained from Adaptive Optics as in this case Shack-Hartmann wavefront sensors in the ground station is analysed. The other part in the thesis is the analysis of the power vectors received during the data transmission from aircraft to the ground station. Finite State Space Markov Model is created for the analysis of the power vectors that are received with receivers of di fferent aperture size.

  • 176.
    Shaheen, Shakira
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Mohammed, Abbas
    Grbic, Nedelko
    Mobile Services for Diabetic Patients' Sustainable Lifestyle2015Inngår i: mHealth Multidisciplinary Verticals / [ed] Adibi, S, CRC Press, 2015, s. 51-61Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 177.
    Shahid, Muhammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Methods for Objective and Subjective Video Quality Assessment and for Speech Enhancement2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The overwhelming trend of the usage of multimedia services has raised the consumers' awareness about quality. Both service providers and consumers are interested in the delivered level of perceptual quality. The perceptual quality of an original video signal can get degraded due to compression and due to its transmission over a lossy network. Video quality assessment (VQA) has to be performed in order to gauge the level of video quality. Generally, it can be performed by following subjective methods, where a panel of humans judges the quality of video, or by using objective methods, where a computational model yields an estimate of the quality. Objective methods and specifically No-Reference (NR) or Reduced-Reference (RR) methods are preferable because they are practical for implementation in real-time scenarios. This doctoral thesis begins with a review of existing approaches proposed in the area of NR image and video quality assessment. In the review, recently proposed methods of visual quality assessment are classified into three categories. This is followed by the chapters related to the description of studies on the development of NR and RR methods as well as on conducting subjective experiments of VQA. In the case of NR methods, the required features are extracted from the coded bitstream of a video, and in the case of RR methods additional pixel-based information is used. Specifically, NR methods are developed with the help of suitable techniques of regression using artificial neural networks and least-squares support vector machines. Subsequently, in a later study, linear regression techniques are used to elaborate the interpretability of NR and RR models with respect to the selection of perceptually significant features. The presented studies on subjective experiments are performed using laboratory based and crowdsourcing platforms. In the laboratory based experiments, the focus has been on using standardized methods in order to generate datasets that can be used to validate objective methods of VQA. The subjective experiments performed through crowdsourcing relate to the investigation of non-standard methods in order to determine perceptual preference of various adaptation scenarios in the context of adaptive streaming of high-definition videos. Lastly, the use of adaptive gain equalizer in the modulation frequency domain for speech enhancement has been examined. To this end, two methods of demodulating speech signals namely spectral center of gravity carrier estimation and convex optimization have been studied.

  • 178.
    Shahid, Muhammad
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Khatibi, Siamak
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Tuemay, Yared
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Popularity index through video semantic quality assessment2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Popularity of the streaming media content such as videos can be ascribed to the perceptual quality, to some extent, of the content. The traditional methods of audio/video quality assessment lack in provision of the input from higher cognitive of the human perception. Some studies have revealed that liking or disliking of a certain content can bias the human judgement towards video quality. In this paper, we have examined the impact of the use of semantic quality indicators namely audio content, audio quality, video content, and video quality in the assessment of quality of a video. Further, we have proposed a methodology to use these indicators for designing a prediction model for the popularity of streaming videos.

  • 179.
    Shahid, Muhammad
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Panasiuk, Joanna
    Van Wallendael, Glenn
    Barkowsky, Marcus
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Predicting full-reference video quality measures using HEVC bitstream-based no-reference features2015Inngår i: International Workshop on Quality of Multimedia Experience, IEEE Communications Society, 2015, Vol. Article number 7148118Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents bitstream-based features for perceptual quality estimation of HEVC coded videos. Various factors including the impact of different sizes of block-partitions, use of reference-frames, the relative amount of various prediction modes, statistics of motion vectors and quantization parameters are taken into consideration for producing 52 features relevant for perceptual quality prediction. The used test stimuli constitutes 560 bitstreams that have been carefully extracted for this analysis from the 59, 520 bistreams of the large-scale database generated by the Joint Effort Group (JEG) of the Video Quality Experts Group (VQEG). The obtained results show the significance of the considered features through reasonably accurate and monotonic prediction of a number of objective quality metrics. © 2015 IEEE.

  • 180.
    Shahid, Muhammad
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Pandremmenou,, Katerina
    Univ Ioannina, GRC.
    Lisimachos P., Kondi
    Univ Ioannina, GRC.
    Andreas, Rossholm
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Perceptual quality estimation of H.264/AVC videos using reduced-reference and no-reference models2016Inngår i: Journal of Electronic Imaging (JEI), ISSN 1017-9909, E-ISSN 1560-229X, Vol. 25, nr 5Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Reduced-reference (RR) and no-reference (NR) models for video quality estimation, using featuresthat account for the impact of coding artifacts, spatio-temporal complexity, and packet losses, are proposed. Thepurpose of this study is to analyze a number of potentially quality-relevant features in order to select the mostsuitable set of features for building the desired models. The proposed sets of features have not been used in theliterature and some of the features are used for the first time in this study. The features are employed by the leastabsolute shrinkage and selection operator (LASSO), which selects only the most influential of them toward per-ceptual quality. For comparison, we apply feature selection in the complete feature sets and ridge regression onthe reduced sets. The models are validated using a database of H.264/AVC encoded videos that were subjec-tively assessed for quality in an ITU-T compliant laboratory. We infer that just two features selected by RRLASSO and two bitstream-based features selected by NR LASSO are able to estimate perceptual qualitywith high accuracy, higher than that of ridge, which uses more features. The comparisons with competingworks and two full-reference metrics also verify the superiority of our models.

  • 181.
    Shahid, Muhammad
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Rossholm, Andreas
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    No-reference image and video quality assessment: a classification and review of recent approaches2014Inngår i: EURASIP Journal on Image and Video Processing, ISSN 1687-5176, E-ISSN 1687-5281, Vol. 2014, nr 40Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The field of perceptual quality assessment has gone through a wide range of developments and it is still growing. In particular, the area of no-reference (NR) image and video quality assessment has progressed rapidly during the last decade. In this article, we present a classification and review of latest published research work in the area of NR image and video quality assessment. The NR methods of visual quality assessment considered for review are structured into categories and subcategories based on the types of methodologies used for the underlying processing employed for quality estimation. Overall, the classification has been done into three categories, namely, pixel-based methods, bitstream-based methods, and hybrid methods of the aforementioned two categories. We believe that the review presented in this article will be helpful for practitioners as well as for researchers to keep abreast of the recent developments in the area of NR image and video quality assessment. This article can be used for various purposes such as gaining a structured overview of the field and to carry out performance comparisons for the state-of-the-art methods.

  • 182.
    Shahid, Muhammad
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Shahzad, Raja Muhammad Khurram
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Selection of a Graduate Thesis Topic in a Multicultural Educational Environment2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This article presents a case study, performed at Blekinge Institute of Technology (BTH), Sweden, about the topic selection routines for a graduate thesis. The study focuses on the international graduate students who are having different academic cultures of their respective countries. Given that BTH has succeeded in the provision of an academic environment that has been efficient in absorbing different academic cultures in a productive manner at a reasonably good scale. However, in a multi-cultural educational environment, it is a challenge for most international students to adapt to the new academic culture and select the graduate thesis topic according to their real potential. Our findings gathered through an online survey, questionnaire, and focus group discussion is presented. The conclusions indicate, albeit, BTH has well defined routines for the thesis selection, the international graduate students face problems at the stage of thesis selection. The article concludes with suggestions to refine the thesis selection process at the micro level to help both students and staff.

  • 183.
    Shahid, Muhammad
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Sogaard, Jacob
    Pokhrel, Jeevan
    Brunnström, Kjell
    Wang, Kun
    Tavakoli, Samira
    Garcia, Narciso
    Crowdsourcing Based Subjective Quality Assessment of Adaptive Video Streaming2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In order to cater for user’s quality of experience (QoE) requirements, HTTP adaptive streaming (HAS) based solutions of video services have become popular recently. User QoE feedback can be instrumental in improving the capabilities of such services. Perceptual quality experiments that involve humans are considered to be the most valid method of the assessment of QoE. Besides lab-based subjective experiments, crowdsourcing based subjective assessment of video quality is gaining popularity as an alternative method. This paper presents insights into a study that investigates perceptual preferences of various adaptive video streaming scenarios through crowdsourcing based subjective quality assessment.

  • 184.
    Shahzad, Muhammad
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Muhammad, Aziz
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    PERFORMANCE ANALYSIS OF WAVELET AND FOURIERTRANSFORMS APPLIED TO NON-STATIONARYVIBRATION DATA2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Machine condition monitoring is one of the most important and a highly

    demanding field and had captured the attention of majority of researchers

    working on efficient fault detection techniques. Early fault detection in ma-chine condition monitoring not only ensures the smooth operation of the

    machinery but also reduces the maintenance cost. Frequency domain anal-ysis is an effective tool for earlier fault detection techniques. To analyze a

    signal’s frequency domain properties, the Discrete Time Fourier Transform

    is a useful tool. For a certain block length, there is a particular time and

    frequency resolution. In case of non stationary signals the Wavelet Trans-form may also be used which does not have a constant time and frequency

    resolution for a particular block length. A comparative performance analysis

    of both techniques using vibration data is presented on the basis of results

    to show the efficiency and scope of each technique. The analysis is based

    on advantages and disadvantages of both the techniques over each other to

    analyze the stationary and non-stationary vibration signals.

  • 185. Sharafi, A.
    et al.
    Khan, Imran
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Zackrisson, Johan
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Håkansson, Lars
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Development and Implementation of an Ad-vanced Remotely Controlled Vibration Laboratory2014Inngår i: proceedings of REV 2014 International Conference on Remote Engineering and Virtual Instrumentation, IEEE Computer Society, 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Currently an advanced remotely controlled vibration laboratory is developed and implemented at Blekinge Institute of Technology, Karlskrona, Sweden. The new developments in the laboratory setup will provide users to carry out vibration measurements on a cantilever beam system with remotely adjustable dynamic properties and to estimate dynamic characteristics of it. The dynamic properties of the cantilever beam are remotely modified by attaching structural parts such as a block of mass, a spring mass system and a non-linear spring. In the development of this remote-lab, a number of different approaches were adopted for the production of well-defined experiments. Also, the new prototype laboratory is designed based on finite elements modeling (FEM) and LABVIEW. The test object, attachment mechanism for sub structures, relevant experiments, and proper interface for managing the lab via Internet and many other things have been considered.

  • 186.
    Shashidhar, Sanda
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Sravya, Amirisetti
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Online Handwritten Signature Verification System: using Gaussian Mixture Model and Longest Common Sub-Sequences2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 187.
    SHI, LEI
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    CHE, JUN
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Design on Hybrid RFID & Ultrasound Based 2D Indoor Positioning System2013Independent thesis Basic level (degree of Bachelor)Oppgave
    Abstract [en]

    As the positioning technology is becoming more advanced, people’s demands increase progressively on the indoor positioning system, since Global Positioning System (GPS) already cannot meet these demands. In order to solve the problem of accuracy and stability of the indoor positioning system, an indoor positioning system which is based on Radio Frequency Identification Devices (RFID) has been developed rapidly. In this project we propose to design an indoor positioning system based on RFID, and make the system on purpose of guaranteeing the rapid response and accurate positioning so as to achieve a low cost and low energy consumption. We combine the features of RFID and ultrasonic system together in an effort to complete the indoor localization. This system is divided into two modules: one is RFID identity module and the other is ultrasonic positioning module. The RFID identity module depends on RFID’s rapid response ability and it is widely covered to the recognized targets. The ultrasonic positioning module by receiving ultrasonic signal measures the target distance and sends the results to the microprocessor to implement the positioning. This thesis also describes the hybrid indoor positioning system structure. It presents the influence of different ultrasonic sensors on the ultrasonic positioning module and the test results for the prototype of ultrasonic range finder module. Meanwhile the test results and the accuracy of positioning are also analyzed in this thesis.

  • 188. Slanina, M.
    et al.
    Shahid, Muhammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    H.264 video encoder implementation impact on decoded picture quality in error prone IPTV environment2015Inngår i: International Congress on Ultra Modern Telecommunications and Control Systems and Workshops, IEEE Computer Society, 2015, Vol. 2016-January, s. 116-122Konferansepaper (Fagfellevurdert)
    Abstract [en]

    H.264/AVC is currently the most popular standard in use for video encoding. To achieve efficient coding while maintaining the desired level of the visual quality and to combat the distortions that may get introduced while transmission through lossy channels, it is imperative to use the best possible coding methodologies. To this end, it is desirable to ascertain the available implementations of the standard under various conditions of coding and levels of network perturbations. We present here the results of evaluating the behavior of two widely used freely available (JM and x264) and one commercially available (Elecard) H.264/AVC based encoders for encoding of high definition (HD) videos through simulated error-prone networks. For the evaluation, we employed the widely used and well understood peak signal to nois ratio (PSNR). We use the Mann-Whitney test to reveal the differences in objective scores and prove a strong content dependency of results, which prevents us from favoring one implementation above the others. Interestingly, we find that for all implementations, that lossy transmission causes sequences encoded at higher bitrates to give worse scores than low bitrate videos subject to the same distortion. © 2015 IEEE.

  • 189.
    Srikrishna Reddy, Addula
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling. Tampere University of Technology.
    Cell Death State Classification by Using Image Processing Methods2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The cell population is used to determine the effect of a drug to understand the disease mechanisms. Thus the analysis of the population behavior provides new insights in medicine development. This project focuses on developing a simple method for cell images which have low resolution and high complexity. The various techniques such as image thresholding, watershed segmentation, opening, dilation, contrast stretching are applied in segmentation and analysis of the image. The estimate of the cell boundary is done using the nucleus image which is assumed as the central part of the considered cells. The cancer cell images of Scott and White(SW) cel line of Beta Catenin(BC) and Krupel Like Factor(KLF) genes have been analyzed and the corresponding average intensity data of the population and a comparison of the Otsu and Huang thresholding methods has been produced. The softwares used in the project are MATLAB 2014 and ImageJ.

  • 190.
    Ström Bartunek, Josef
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    FINGERPRINT IMAGE ENHANCEMENT, SEGMENTATION AND MINUTIAE DETECTION2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Prior to 1960's, the fingerprint analysis was carried out manually by human experts and for forensic purposes only. Automated fingerprint identification systems (AFIS) have been developed during the last 50 years. The success of AFIS resulted in that its use expanded beyond forensic applications and became common also in civilian applications. Mobile phones and computers equipped with fingerprint sensing devices for fingerprint-based user identification are common today.

    Despite the intense development efforts, a major problem in automatic fingerprint identification is to acquire reliable matching features from fingerprint images with poor quality. Images where the fingerprint pattern is heavily degraded usually inhibit the performance of an AFIS system. The performance of AFIS systems is also reduced when matching fingerprints of individuals with large age variations.

    This doctoral thesis presents contributions within the field of fingerprint image enhancement, segmentation and minutiae detection. The reliability of the extracted fingerprint features is highly dependent on the quality of the obtained fingerprints. Unfortunately, it is not always possible to have access to high quality fingerprints. Therefore, prior to the feature extraction, an enhancement of the quality of fingerprints and a segmentation are performed. The segmentation separates the fingerprint pattern from the background and thus limits possible sources of error due to, for instance, feature outliers. Most enhancement and segmentation techniques are data-driven and therefore based on certain features extracted from the low quality fingerprints at hand. Hence, different types of processing, such as directional filtering, are employed for the enhancement. This thesis contributes by proposing new research both for improving fingerprint matching and for the required pre-processing that improves the extraction of features to be used in fingerprint matching systems.

    In particular, the majority of enhancement and segmentation methods proposed herein are adaptive to the characteristics of each fingerprint image. Thus, the methods are insensitive towards sensor and fingerprint variability. Furthermore, introduction of the higher order statistics (kurtosis) for fingerprint segmentation is presented. Segmentation of the fingerprint image reduces the computational load by excluding background regions of the fingerprint image from being further processed. Also using a neural network to obtain a more robust minutiae detector with a patch rejection mechanism for speeding up the minutiae detection is presented in this thesis.

  • 191.
    Syrko, Ariel
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Development and evaluation of a framework for semi-automated formalization of automotive requirements.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Quantity and intricacy of features implemented in vehicle have expanded rapidly over a past few years. Currently vision of autonomous vehicle is no longer a dream or SF movie, but instead a coming reality. In order to reach the better quality and high safety, advanced verification techniques are required. Simulink Design Verifier is a model checking tool based on formal verification, which can be effectively used to solve problems concerning error detection and testing at earlier stages of project. The transformation of requirements written in traditional form into Simulink Design Verifier objectives can be time consuming as well as requiring knowledge of system model and the verification tools.

    In order to reduce time consumption and to guide a user through the system model and the verification tool, the semi-automated framework has been developed. An implementation of restricted English grammar patterns into Simulink objects supports description of patterns to engineers and reduces time consumption. The developed framework is flexible and intuitive hence can be a solution for other branches of industry, but further tests and verification would be required.

    This thesis highlights the whole process of transformation system requirements written in natural language into Simulink Design Verifier objectives. The Fuel Level Display System model currently used by almost all Scania’s vehicles is analysed. Limitations and errors encountered during development process like a flexibility of Simulink Design Verifier to capture requirements and the patterns behaviour or ambiguity of system requirements are analysed and described in this thesis.

  • 192.
    Szczepański, Szymon Janusz
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Szyca, Michał Stanisław
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Music Information Retrieval. A case study of MIR in modern rock and metal music2014Independent thesis Advanced level (degree of Master (Two Years))Oppgave
    Abstract [en]

    "Music Information Retrieval (MIR) is a multidisciplinary research endeavor that strives to develop innovative content-based searching themes, novel interfaces, and evolving networked delivery mechanisms in an effort to make worlds vast store of music accessible to all" (Downie, summer 2004). The purpose of this study is analysis of some MIR algorithms and their efficiency on modern rock and metal songs. To do so, one algorithm for four of most commonly MIR uses was chosen, described and evaluated on full songs or fragments of them. Music separation part proved that it is possible to effectively separate repeating background. Audio fingerprinting experiments show that higher quality of records generate significantly better results. Modern metal music turned out to be difficult for tempo estimation and chord recognition was working. All results show that modern rock and metal music, even though complicated, can be analyzed but still needs more research in this field to make it effectively.

  • 193.
    Tahir, Muhammad Faisal
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Global Positioning System (GPS) Based Location Finder on Android2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This thesis presents the development of an android application which has the capability of using the concepts of augmented reality to submerge the virtual information of user’s surroundings by detecting and tracking user’s location in real time.Eclipse is an open source software, used in professional development of software solutions and programming applications. It provides extensive availability of free libraries. It has been employed for the development of software used in this thesis.As the android GPS is notified, the application is fully location aware which keeps the track of user’s location. When the user points the camera in a specific direction, the application tracks the camera orientation and displays the records of a specific place. Then the application keeps on updating the information as the direction changes. The additional information is displayed with the help of "Google" databases. The information when gathered is then displayed to the live feed of camera which helps the users to interact in a more reliable way. Option for viewing the places in map view with the help of Google Maps is also available.

    Keywords: Java, Android, Database management system,Desktop applications, Google databases, Maps

  • 194.
    Tammireddy, Prahallada Reddy
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Tammu, Rajesh
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Image Reconstruction using wavelet transform with extended fractional fourier Transform2014Independent thesis Advanced level (degree of Master (Two Years))Oppgave
    Abstract [en]

    Image reconstruction forms the basis of many applications in the fields of medicine, astronomy etc. Historically an image is reconstructed using several methods of which Fourier and wavelet transform methods formed the roots of present day technologies. The reconstructed images possess higher resolution and helps in analyzing the image in more detail. In our thesis we proposed a method where we used fractional Fourier transform in conjunction with wavelet transform to produce the reconstructed image. We employed three wavelets in our thesis namely Haar wavelet, Daubechies wavelet and Coiflet wavelet in order to gain diversity into our results. For the scaling function of each of the three wavelets fractional Fourier transform is applied which gives a new scaling function. A new wavelet function created using the scaling function. Such a wavelet is applied to series of images of various resolutions (256x256, 128x128, 64x64) and is encrypted using DES before transmitting over the channel. The reconstruction is carried out using inverse DES and inverse wavelet Transform to get the reconstructed image. The parameters we used to determine the efficiency of the wavelets are peak signal to noise ratio(PSNR) and Structural similarity Index(SSIM). The results for various images are plotted using box plots. We reached out the conclusions that Daubechies had the better performance compared to other wavelets. Also the performance falls down with the image resolution.

  • 195.
    TANTEH, DERICK NJOMBOG
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    AL-LIDDAWI, SHAFIQ YOUSEF
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    SSEKASIKO., DANIEL
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    PROPERTIES OF TRANSFORMER OIL THAT AFFECT EFFICIENCY.2014Oppgave
    Abstract [en]

    Abstract. Transformer explosions caused by dielectric failure account for over 50% of the disasters. The aim of this thesis is to examine, compare and outline the differences, in function, as dielectric insulators, vegetables oil has, with respect to the mineral oil used in high-power transformers. We will first consider the vegetable oil which has less dielectric capabilities than the mineral oil used in power transformers. Later in the experiments, we will focus mainly to examine the breakdown voltage property, as we try to alter some properties of the respective oils used. Considering the fact that vegetable oil has low viscosity, with its chemical compounds constituting less molecular masses compared to mineral oil, we endorse, from our experimental findings, that mineral oil is indeed worthy and reasonable to be used as a dielectric in high power transformers. In this write-up, we have considered eleven transformer oil properties. In the experiment proper, we considered only the acidity, whose concentration in the transformer oil increases with aging if the transformer, moisture, and a ‘suitable’ impurity like NaOH(aq). At first glance, one would be tempted to think, as we were, that since the increase in acid content of the oil deteriorates its dielectric performance, an increase in alkaline content of the transformer oil, would increase its dielectric ability; reversing the acid effect. But as we see in the results from our experiments, this is false. We think that the visible degradation of the insulating property of the oil, with the introduction of NaOH(aq), is because it acts as an impurity to suitable dielectric function. From the experiments, the heating procedures resulted in the production of toxic gases. This indicated the actual loss of chemical structure and significant breakage of chemical bonds. The resulting chemical composition of the oil does not produce the same dielectric properties as the initial oil sample. Also, here has been considerable inconsistency in the addition of NaOH(aq) or HCl(aq) to both oils. We only added HCl(aq), before every measurement, in two of the experiments. The other experiments were either with moisture, or a single addition of 2cm3 of either HCl(aq) or NaOH(aq) before heating; after which several measurements were taken, at specific intervals, as the mixture cools. We did so, in the latter, in which we had only one addition of a 2cm3 chemical, because in real life, given the short time frame of the experiment, the total amount of acid in the oil has a negligible change. So, in a functioning heated transformer, within a short time frame, there is actually deterioration in oil insulation properties

  • 196. Tavakoli, Samira
    et al.
    Brunnström, Kjell
    Wang, Kun
    Andrén, Börje
    Shahid, Muhammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Garcia, Narciso
    Subjective quality assessment of an adaptive video streaming model2014Inngår i: IMAGE QUALITY AND SYSTEM PERFORMANCE XI / [ed] Triantaphillidou, S; Larabi, MC, San Francisco: SPIE , 2014, Vol. 9016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    With the recent increased popularity and high usage of HTTP Adaptive Streaming (HAS) techniques, various studies have been carried out in this area which generally focused on the technical enhancement of HAS technology and applications. However, a lack of common HAS standard led to multiple proprietary approaches which have been developed by major Internet companies. In the emerging MPEG-DASH standard the packagings of the video content and HTTP syntax have been standardized; but all the details of the adaptation behavior are left to the client implementation. Nevertheless, to design an adaptation algorithm which optimizes the viewing experience of the enduser, the multimedia service providers need to know about the Quality of Experience (QoE) of different adaptation schemes. Taking this into account, the objective of this experiment was to study the QoE of a HAS-based video broadcast model. The experiment has been carried out through a subjective study of the end user response to various possible clients' behavior for changing the video quality taking different QoE-influence factors into account. The experimental conclusions have made a good insight into the QoE of different adaptation schemes which can be exploited by HAS clients for designing the adaptation algorithms.

  • 197. Tavakoli, Samira
    et al.
    Shahid, Muhammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Brunnström, Kjell
    Lövström, Benny
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Narciso, Garcia
    Effect of content characteristics on quality of experience of adaptive streaming2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The growing popularity of adaptive streaming-based video delivery nowadays has raised the interest about the user's perception when experiencing quality adaptation. The impact of the video content characteristics on user's perceptual quality has already become evident. The aim of this study is to investigate the influence of this factor on the quality of experience of adaptive streaming scenarios. Our results show that the perceptual quality of adaptation strategies applied on videos with high spatial and low temporal amount of activity is significantly lower compared to the other content types.

  • 198.
    Terneux, Efrén Andrés Estrella
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Design of an Algorithm for Aircraft Detection and Tracking with a Multi-coordinate VAUDEO System2014Independent thesis Advanced level (degree of Master (Two Years))Oppgave
    Abstract [en]

    The combination of a video camera with an acoustic vector sensor (AVS) opens new possibilities in environment awareness applications. The goal of this thesis is the design of an algorithm for detection and tracking of low-flying aircraft using a multi-coordinate VAUDEO system. A commercial webcam placed in line with an AVS in a ground array are used to record real low-flying aircraft data at Teuge international airport. Each frame, the algorithm analyzes a matrix of three orthogonal acoustic particle velocity signals and one acoustic pressure signal using the Singular Value Decomposition to estimate the Direction of Arrival, DoA of propeller aircraft sound. The DoA data is then applied to a Kalman filter and its output is used later on to narrow the region of video frame processed. Background subtraction is applied followed by a Gaussian-weighted intensity mask to assign high priority to moving objects which are closer to the sound source estimated position. The output is applied to another Kalman filter to improve the accuracy of the aircraft location estimation. The performance evaluation of the algorithm proved that it is comparable to the performances of state-of-the-art video alone based algorithms. In conclusion, the combination of video and directional audio increases the accuracy of propeller aircraft detection and tracking comparing to reported previous work using audio alone.

  • 199.
    Thati, Satish Kumar
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Mareedu, Venkata Praneeth
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Determining the Quality of Human Movement using Kinect Data2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Health is one of the most important elements in every individual’s life. Even though there is much advancement in science, the quality of healthcare has never been up to the mark. This appears to be true especially in the field of Physiotherapy. Physiotherapy is the analysis of human joints and bodies and providing remedies for any pains or injuries that might have affected the physiology of a body. To give patients a top notch quality health analysis and treatment, either the number of doctors should increase, or there should be an alternative replacement for a doctor. Our Master Thesis is aimed at developing a prototype which can aid in providing healthcare of high standards to the millions. 

    Methods: Microsoft Kinect SDK 2.0 is used to develop the prototype. The study shows that Kinect can be used both as Marker-based and Marker less systems for tracking human motion. The degree angles formed from the motion of five joints namely shoulder, elbow, hip, knee and ankle were calculated. The device has infrared, depth and colour sensors in it. Depth data is used to identify the parts of the human body using pixel intensity information and the located parts are mapped onto RGB colour frame.  The image resulting from the Kinect skeleton mode was considered as the images resulting from the markerless system and used to calculate the angle of the same joints. In this project, data generated from the movement tracking algorithm for Posture Side and Deep Squat Side movements are collected and stored for further evaluation. 

    Results: Based on the data collected, our system automatically evaluates the quality of movement performed by the user. The system detected problems in static posture and Deep squat based on the feedback on our system by Physiotherapist.

  • 200.
    Tiancheng, Zhang
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Yunlin, Zhang
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    High voltage Direct Current lines in the Chinese electric power system2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
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