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1
Madhi, Kristi. "Impact of QoS and contextual parameters on QoE in a videoconferencing application." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204918.
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This project will be based in an objective and as well as subjective study related to Quality of Experience in a video conference application, appear.in. Indeed the study puts emphasis on finding possible correlations between Quality of Service parameters, that in the study are represented by some of the most meaningful network parameters, and contextual parameters with Quality of Experience. To achieve this the study was based in two different scenarios using two test environments. One is based on having an all free test and the other conducted in a created test-bad for monitoring and altering network parameters to see how user respond to the changes. Both scenarios were accompanied by a survey that provided useful information about the subjective perception of different individuals that took part in the testing phase.The project is divided in two phases where we set up the required environments for the test and then we process results to find correlation between the above mentioned parameters.In the end of the project all the results and the conclusions are presented providing a clearer view for what was done. The project itself might represent a good foundation to be used in the future for other studies related to video conferencing application.
2
Hjalmarsson, Henrik. "Automatic configuration of QoS parameters in IP RAN." Thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-95147.
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This thesis discusses methods for automating the configuration process of an IP network. Focus lies on automating the configuration of Quality of Service parameters in an Ericsson IP RAN, a network that poses some constraints to the work, such as containing a diverse set of nodes and users with extremely high demands on service quality compared to other IP networks. It is possible to automate almost any task during IP network configuration, provided that there is a general system for transmitting data to every node in the network. Currently there is no such general system at Ericsson. The system created in this thesis is a prototype that shows how an application could be created and how it will have to interact with the communication part of an existing system to provide functionality for automation.
3
SANTOS, ALEXANDRE FERREIRA DOS. "ASSESSMENT OF QOS PARAMETERS IN VOICE OVER IP TRANSMISSION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=5243@1.
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Este trabalho apresenta um estudo visando a estabelecer uma
metodologia
para dimensionamento de um sistema VoIP, focalizando, em
particular, o
dimensionamento de um multiplexador estatístico. Procuramos
aplicar modelos e
resultados existentes para o problema geral do
multiplexador estatístico ao caso
específico de um sistema VoIP, levando em conta as
características do tráfego, os
requisitos de QoS e os princípios das arquiteturas Intserv
e Diffserv. Para isto,
apresentamos um resumo da tecnologia VoIP, incluindo seus
requisitos de
qualidade e os protocolos apropriados para transportar este
tipo de mídia na
Internet. Discorremos sobre os mecanismos de controle de
tráfego usuais em redes
de pacotes com QoS, assim como sobre as Arquiteturas de QoS
definidas pelo
IETF . É apresentada uma revisão de modelos de tráfego e
modelos aplicáveis à
análise de multiplexadores estatísticos, com destaque para
o chamado modelo
fluido aplicado à descrição do tráfego gerado por um
agregado homogêneo de
fontes de voz, além de um estudo comparativo entre
respostas obtidas
analiticamente com aquelas obtidas por meio de simulação. A
influência do tipo
de codificador e de parâmetros como tamanho de pacote é
investigada,
mostrando-se a dificuldade em se dispor de um modelo
analítico capaz de levar
em conta, de forma precisa, os diferentes formatos do
sistema VoIP. Por fim,
estabelece-se um cenário para aplicação dos modelos a um
sistema VoIP.<br>This work presents a study aiming at to establish a
methodology for sizing a
VoIP system, focusing, in particular, the sizing of a
statistical multiplexer. We
apply existing models and results for the general problem
of the statistical
multiplexer to the specific case of a VoIP system, taking
in account the
characteristics of the traffic, the requirements of QoS and
the principles of the
architectures Intserv and Diffserv. For this, we present a
summary of the VoIP
technology, including its requirements of quality and the
protocols appropriate to
carry this type of media in the Internet. We discourse on
the usual mechanisms of
traffic control in packet networks with QoS, as well as on
the Architectures of
QoS defined by the IETF. A revision of traffic models and
applicable models to
the analysis of statistical multiplexers, with prominence
for the fluid model
applied to the description of the traffic generated for a
homogeneous aggregate of
voice sources, is presented. Besisdes, a comparative study
of behavior gotten
analytically with those gotten by means of simulation is
made. The influence of
the coder and parameters as so packet size is investigated,
revealing the difficulty
in finding an analytical model capable to take in account,
with precision, the
different formats of the VoIP system. Finally, we establish
a scenario for
application of the models to a VoIP system.
4
Niemelä, Markus. "Estimating Internet-scale Quality of Service Parameters for VoIP." Thesis, Linköpings universitet, Programvara och system, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-127360.
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With the rising popularity of Voice over IP (VoIP) services, understanding the effects of a global network on Quality of Service is critical for the providers of VoIP applications. This thesis builds on a model that analyzes the round trip time, packet delay jitter, and packet loss between endpoints on an Autonomous System (AS) level, extending it by mapping AS pairs onto an Internet topology. This model is used to produce a mean opinion score estimate. The mapping is introduced to reduce the size of the problem in order to improve computation times and improve accuracy of estimates. The results of testing show that estimating mean opinion score from this model is not desirable. It also shows that the path mapping does not affect accuracy, but does improve computation times as the input data grows in volume.
5
Alreshoodi, Mohammed A. M. "Prediction of quality of experience for video streaming using raw QoS parameters." Thesis, University of Essex, 2016. http://repository.essex.ac.uk/16566/.
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Along with the rapid growth in consumer adoption of modern portable devices, video streaming is expected to dominate a large share of the global Internet traffic in the near future. Today user experience is becoming a reliable indicator for video service providers and telecommunication operators to convey overall end-to-end system functioning. Towards this, there is a profound need for an efficient Quality of Experience (QoE) monitoring and prediction. QoE is a subjective metric, which deals with user perception and can vary due to the user expectation and context. However, available QoE measurement techniques that adopt a full reference method are impractical in real-time transmission since they require the original video sequence to be available at the receiver’s end. QoE prediction, however, requires a firm understanding of those Quality of Service (QoS) factors that are the most influential on QoE. The main aim of this thesis work is the development of novel and efficient models for video quality prediction in a non-intrusive way and to demonstrate their application in QoE-enabled optimisation schemes for video delivery. In this thesis, the correlation between QoS and QoE is utilized to objectively estimate the QoE. For this, both objective and subjective methods were used to create datasets that represent the correlation between QoS parameters and measured QoE. Firstly, the impact of selected QoS parameters from both encoding and network levels on video QoE is investigated. The obtained QoS/QoE correlation is backed by thorough statistical analysis. Secondly, the development of two novel hybrid non-reference models for predicting video quality using fuzzy logic inference systems (FIS) as a learning-based technique. Finally, attention was move onto demonstrating two applications of the developed FIS prediction model to show how QoE is used to optimise video delivery.
6
Fey, Enikö. "The Effect of Combining Network and Server QoS Parameters on End-to-End Performance." Thesis, KTH, Teleinformatik, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-93516.
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Application hosting is becoming a popular business, Application Service Providers (ASPs) need however to keep up with the increasing pace of the market. This implies that they have to provide infrastructure to an increasing number of clients, and at the same time give QoS guarantees to these clients. One solution for ASPs to both guarantee a certain service level (QoS) for their clients and keep expanding would be to have so many resources as to be able to provide more than the maximum aggregate need of their clients. This may turn out to be an expensive or even an impossible solution - sharing infrastructure between clients and offering some means of resource reservation, and using charging to insure that clients only reserve the resources they need, is an alternative. It is however not an easy problem to solve, particularly if the procedure of adding new clients is to be automated, and the resources dynamically allocated. The ICorpMaker framework being developed at the IBM Zurich Research Laboratory offers a solution to the above named problems. In the ICorpMaker framework dynamic resource allocation is achieved by letting clients modify the amount of resources allocated to them in a simple manner, requesting more or less resources than their current allotment. The difficulty in achieving the end-to-end performance the client desires, lies in the fact that it is not certain how modifying resource allocation at the network respectively server level will combine and affect the end-to-end performance experienced by the end users of the service. The aim of this thesis project was to study the correlation between different network and server QoS parameters and the resulting end-to-end performance by making measurements. The results obtained from these measurements give an answer to the question of how to change the network and server resource allocations, when a client's application does not perform in a satisfactory way and hence the client requests more resources. Certain optimizations for the resource (re)allocation were also suggested based on the results.
7
Pota, Zainab Abbas. "Simulation Analysis of Quality of Service Parameters for On-board Switching on ATM Network for Multimedia Applications." University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1289802401.
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Sukup, Luboš. "Metody měření výkonnostních a kvalitativních parametrů datových sítí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-264927.
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Master thesis involves the development of quality measurement issues and performance parameters in data networks. It describes the main technologies as they affect the quality and performance parameters and the effect of these parameters for voice, video and data services. Next are listed some methods for measuring parameters of the data network.In the practical part is selected one method of measuring network parameters and properties of this method are demonstrated by illustrative examples.
9
Martín, Severiano Juan Carlos. "IEEE 802.11b MAC layer's influence on VoIP quality parameters : Measurements and Analysis." Thesis, KTH, Mikroelektronik och informationsteknik, IMIT, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-92577.
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Real-time voice measurements were performed to assess whether there are significant problems with 802.11b wireless networks regarding real-time voice communication. We present an analysis of how the 802.11b MAC protocol and diverse environmental conditions affect the quality of real-time voice in terms of loss, delay, and jitter. We also reveal practical issues of wireless monitoring with passive sniffers for this type of analysis. The results obtained in our measurements show that in the majority of the experiments the quality was good, but under some circumstances the requirements for an acceptable voice communication were not met.<br>Realtidsröstmätningar gjordes för att testa om det finns problem med 802.11b trådlösa nätverk beträffande realtidsröstkommunikation. En analys presenteras av hur 802.11b MACs protokoll och olika tillstånd i omgivningen påverkar kvaliteten på realtidsrösten i form av förluster, fördröjningar och jitter. Även praktiska angelägenheter om trådlös övervakning med passiva sniffers visas. De erhållna resultaten visar att i en majoritet av fallen var kvaliteten acceptabel, men under vissa förhållanden blev inte kraven för röstkommunikation uppfyllda.
10
Shivaprasad, Mala A. "Dynamic Dealy Compensation and Synchronisation Services for Continuous Media Streams." Thesis, Indian Institute of Science, 1995. https://etd.iisc.ac.in/handle/2005/144.
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Multimedia' nature of an application refers to the presence of several media streams in parallel. Whether it is receiving real-time data or retrieving stored data, there exists an end-to-end delay in data transfer from source to destination over the network. This delay experienced can be split into a fixed part and a variable part. Data processing time like coding and decoding at the source and destination are the fixed delays experienced. The variable delay occurs mainly due to queuing at the intermediate nodes during its flow through the network. The variable or unequal delays introduce gaps or discontinuities within a stream. In multi-stream applications where each stream may flow on different routes based on the bandwidth availability experiencing different delays, mismatch between them can also occur. These discontinuities and skews result in poor quality of playout. Clock drift and variations in drift rates between the source/s and destination/s, clock also lead to poor quality of play out. To eliminate these skews and discontinuities, there must be mechanisms, viz., and synchronisation services to convey, reintroduce and maintain the temporal relationship between the media streams for presentation throughout the playout, at the destination. The reintroduction of this lost temporal relationship within a stream and between various media streams for presentation at the destination is the object of multimedia synchronisation and is the subject matter of this thesis.
In the presence of synchronised clocks, the main cause of asynchronies between media streams is the difference in delays experienced and the jitter. In this work, to convey the temporal relationship between streams of an application to the playout site, each stream is assigned a priority л, based on its importance to the user. The media streams are then divided into synchronisation units called 'Groups' based on that stream's characteristics which has the highest priority л. A group may therefore consist of one video frame and other data which were generated in that interval. Or may consist of silence and talk-spurt periods of the voice stream with data units of other streams generated in the same interval.
Since the quality of playout of temporally related delay-sensitive streams depends upon the delay-experienced, the concept of QoS can be extended to describe the presentation requirements of uch data. Depending on the user perception and the delay experienced, an application can have a range of playout times, giving the best performance. The presentation of many real-time applications can be considered satisfactory even when the delay bound is exceeded by a small amount for a short period of time under varying network conditions. This property can be exploited by defining two sets of QoS parameters, namely QoS optimum and QoSlimit for each real-time application. As the delay and its variations increase, the optimum playout time range
decreases. QoS optimum specifies the performance parameters required to perceive 'realtime'. Multimedia data can be played out at its QoSlimit with a deterioration in quality under poor network conditions still maintaining the synchronisation between streams. To control the playout at two levels of QoS, and maintain intra-media and inter-media synchronisation, stream controllers and super stream controllers have been used.
The dynamic delay compensation algorithm and synchronisation services were simulated using network delay models and performances studied. It is shown that the proposed algorithm not only synchronised media streams and smoothened jitter but also optimised buffer space and buffer occupancy time while meeting the desired quality of service requirements
11
Shivaprasad, Mala A. "Dynamic Dealy Compensation and Synchronisation Services for Continuous Media Streams." Thesis, Indian Institute of Science, 1995. http://hdl.handle.net/2005/144.
Full textAbstract:
Multimedia' nature of an application refers to the presence of several media streams in parallel. Whether it is receiving real-time data or retrieving stored data, there exists an end-to-end delay in data transfer from source to destination over the network. This delay experienced can be split into a fixed part and a variable part. Data processing time like coding and decoding at the source and destination are the fixed delays experienced. The variable delay occurs mainly due to queuing at the intermediate nodes during its flow through the network. The variable or unequal delays introduce gaps or discontinuities within a stream. In multi-stream applications where each stream may flow on different routes based on the bandwidth availability experiencing different delays, mismatch between them can also occur. These discontinuities and skews result in poor quality of playout. Clock drift and variations in drift rates between the source/s and destination/s, clock also lead to poor quality of play out. To eliminate these skews and discontinuities, there must be mechanisms, viz., and synchronisation services to convey, reintroduce and maintain the temporal relationship between the media streams for presentation throughout the playout, at the destination. The reintroduction of this lost temporal relationship within a stream and between various media streams for presentation at the destination is the object of multimedia synchronisation and is the subject matter of this thesis.
In the presence of synchronised clocks, the main cause of asynchronies between media streams is the difference in delays experienced and the jitter. In this work, to convey the temporal relationship between streams of an application to the playout site, each stream is assigned a priority л, based on its importance to the user. The media streams are then divided into synchronisation units called 'Groups' based on that stream's characteristics which has the highest priority л. A group may therefore consist of one video frame and other data which were generated in that interval. Or may consist of silence and talk-spurt periods of the voice stream with data units of other streams generated in the same interval.
Since the quality of playout of temporally related delay-sensitive streams depends upon the delay-experienced, the concept of QoS can be extended to describe the presentation requirements of uch data. Depending on the user perception and the delay experienced, an application can have a range of playout times, giving the best performance. The presentation of many real-time applications can be considered satisfactory even when the delay bound is exceeded by a small amount for a short period of time under varying network conditions. This property can be exploited by defining two sets of QoS parameters, namely QoS optimum and QoSlimit for each real-time application. As the delay and its variations increase, the optimum playout time range
decreases. QoS optimum specifies the performance parameters required to perceive 'realtime'. Multimedia data can be played out at its QoSlimit with a deterioration in quality under poor network conditions still maintaining the synchronisation between streams. To control the playout at two levels of QoS, and maintain intra-media and inter-media synchronisation, stream controllers and super stream controllers have been used.
The dynamic delay compensation algorithm and synchronisation services were simulated using network delay models and performances studied. It is shown that the proposed algorithm not only synchronised media streams and smoothened jitter but also optimised buffer space and buffer occupancy time while meeting the desired quality of service requirements
12
Nagavaram, Ashish. "Cloud Based Dynamic Workflow with QOS For Mass Spectrometry Data Analysis." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1322681210.
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Brandejs, Jakub. "Detekce parametrů repolarizace ze signálu EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220848.
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A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.
14
Grenar, Milan. "Kritické parametry pro bezdrátové sítě WiFi a WiMAX." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-234419.
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My thesis will be aimed at problems of wireless networks WiFi and WiMAX. A modelling of network will be put into effect onto which the measurement will be implemented and the impacts of network load on the data transfer Quality of Service (QoS) will be examined with aiming at VoIP. On this network model a power failure will be simulated and the impacts of this failure after restoring the power supply will be monitored. The aim of this thesis is to check the rate of network throughput while preserving a providing service quality and to suggest an economica1ly acceptable solution of the problems relating to feeding tension outage of the access point (AP) for a practical usage in these networks.
15
Gregor, Lukáš. "Ověřování stabilního provozu sítě nové generace měřením přenosových parametrů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-377341.
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This thesis deals with the measurement of transmission parameters in the new generation access networks NGA. The aim of the thesis is to build and configure a test network and scenarios for the measurement of service quality parameters and then verify the transmission stability. The theoretical part describes general functioning of NGN networks, the requirements of different telecommunications services on quality parameters, methodology and recommendations for measuring transmission parameters in packet networks. The practical part deals with the configuration of scenarios using mainly MPLS technology and methodology of their testing. Measurements were performed according to recommendations IETF RFC 2544, IETF RFC 6349 with the ExacTCP test and ITU-T Y.1564 with the EtherSAM test. For measurements were used measuring instruments of EXFO brand. In conclusion, the measurement results according to the mentioned standards were evaluated and also the advantages of using the measurement according to the given standard in NGA access networks were discussed.
16
Park, Kyoung-Joo Jenny. "Multi-Parameter Fluorescent Analysis and Quantitative Magnetophoresis Study as Two Different Technologies to Detect and Characterize Cells and Its Various Applications as Biomarkers." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1512018964871473.
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Kumar, Tushar. "Characterizing and controlling program behavior using execution-time variance." Diss., Georgia Institute of Technology, 2016. http://hdl.handle.net/1853/55000.
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Immersive applications, such as computer gaming, computer vision and video codecs, are an important emerging class of applications with QoS requirements that are difficult to characterize and control using traditional methods. This thesis proposes new techniques reliant on execution-time variance to both characterize and control program behavior. The proposed techniques are intended to be broadly applicable to a wide variety of immersive applications and are intended to be easy for programmers to apply without needing to gain specialized expertise. First, we create new QoS controllers that programmers can easily apply to their applications to achieve desired application-specific QoS objectives on any platform or application data-set, provided the programmers verify that their applications satisfy some simple domain requirements specific to immersive applications. The controllers adjust programmer-identified knobs every application frame to effect desired values for programmer-identified QoS metrics. The control techniques are novel in that they do not require the user to provide any kind of application behavior models, and are effective for immersive applications that defy the traditional requirements for feedback controller construction. Second, we create new profiling techniques that provide visibility into the behavior of a large complex application, inferring behavior relationships across application components based on the execution-time variance observed at all levels of granularity of the application functionality. Additionally for immersive applications, some of the most important QoS requirements relate to managing the execution-time variance of key application components, for example, the frame-rate. The profiling techniques not only identify and summarize behavior directly relevant to the QoS aspects related to timing, but also indirectly reveal non-timing related properties of behavior, such as the identification of components that are sensitive to data, or those whose behavior changes based on the call-context.
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Prudík, Jiří. "Model metropolitní optické sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217666.
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The purpose of this master’s thesis is foremost to provide a simple guide how to build elements of optical metropolitan area network. The basic model consists to sequence of construction, network topology, passive and active parts. The collection contains examples of alternative technology such as Wireless LAN with different frequency. The optical network construction based on optical cable, fibres, splices, trays, adapters, connectors and active parts for example a lot of media convertor models. After that there are demonstrating type of wavelength division multiplexer used in metropolitan area network – passive planar PCL splitter. One of the passive planar splitter are used to increase optical fibre channel. At the end of the collection a simplified examples of used measurements – optical time domain reflectometry and optical fibre transmission. Contains standard protocols or reflectogram. The conclusion of this thesis summarizes costs of FTTb (Fibre To The Building) model of optical metropolitan area network in Czech republic and future contribution for society.
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Hung, Cheng Chou, and 周紘正. "A Study of Adaptive QoS Parameters for Modeling Internet Performance." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/62220756815232822248.
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碩士<br>東吳大學<br>資訊科學系<br>89<br>Due to the maturity of the transmission techniques on the Internet, the applications of e-commerce and multimedia network are to be the major trend in the future. Therefore, the issue of Quality of Service (QoS) is more essential to the Internet applications. The purpose of QoS is to support the guaranteed bandwidth of transmission service to make the data flows efficiently under acceptable delay, delay jitter and error rate. Also, that will commit the network to provide sufficient resources during the transmission. The Local Area Network (LAN) and Intranet in Asynchronous Transfer Mode (ATM) architecture have supported the QoS service. However, the Internet exists in different sub-networks architectures, which may not support the QoS guarantee. It is very difficult that implements QoS environment on the Internet. In this paper, we will discuss and finalize the influence factors for network performance, and also use the ns-2 simulation tool to consider the concept of queue management, scheduling, and other related network theories. By designing the simulation process to evaluate the Internet performance, we can observe the influence degrees for variations of parameters. Based on the evaluation results and performance analyses, we can find out some suitable parameters values to obtain the better performance on the Internet to avoid the traffic congestion and improve the network throughput. Finally, the quality and efficiency of transmissions are to enhance the processing throughput over several sub-networks, and therefore to ease the adaptability for implementing the QoS Internet.
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Yan, Shi-Jie, and 顏士傑. "Fuzzy-based dynamic QoS parameters estimated by MMPP model for CBWFQ queuing." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/34708370325326760038.
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碩士<br>東海大學<br>資訊工程與科學系<br>93<br>As internet grow rapidly, network traffic become more and more heavy than usual. Network providers have provided more backbones and bandwidth for users, but user's requirements are always much more than supply. Therefore, network congestion becomes serious day by day. Quality of Service (QoS) seems one of the ways to solve this problem.
Many QoS techniques have been so far raised. However, most of them just offer an approach or a platform, no exactly rule can follow up and no flexible system can manage varied network. This thesis proposes a network QoS system named Fuzzy-based Dynamic Resource Allocation System (FDRAS) which partitions network traffic into several channels and recommends suitable queueing strategies to network administrator so that different user traffic and heterogeneous data packets of different classes can be properly multiplexed. Class Based Weighted Fair Queueing (CBWFQ) is deployed as the congestion resolution mechanism. Markov Modulated Poisson Process (MMPP) is encompassed to model network traffic. FDRAS also invokes Expectation Maximization (EM) algorithm to estimate MMPP parameters and Fuzzy Theory to allocate the bandwidth reserved for a channel. Reserving bandwidth guarantees the least network traffic, while declaring threshold of queue limit defines the priority of a class. A packet with higher priority will be delivered with higher probability. Moreover, FDRAS can automatically tune its QoS parameters to adapt varied network traffic, thus decreasing managerial load and providing user a higher network service quality.
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Wang, Rung-yi, and 王榮義. "Study on Relevant of QoS Competition Parameters of Traditional IEEE 802.11 DCF and EDCF." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/d62bz6.
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碩士<br>國立臺灣科技大學<br>電機工程系<br>94<br>The IEEE 802.11wireless LAN (WLAN) is the most widely used standard nowadays for wireless LAN technology. With the development of wireless network and the requirement of real-time service, IEEE 802.11 proposed IEEE802.11e medium access control (MAC) protocol to guarantee quality of service (QoS). The major effect order of priority competition parameter is arbitration inter-frame space (AIFS) and contention window minimum (CWmin). At present there are many research aims at the adjustment competition parameter of quality of service to achieve the different service the goal. But most of them does not explicitly pointed out the correlation between competition parameters and how to adjust competition parameters with each kind of different conditioning.
In this paper, we change individually the arbitration inter-frame space and contention window minimum based on the distributed coordination function (DCF) enhanced distributed coordination function (EDCF) to observe the variation of system throughput and delay time under different number of stations. We present the comparative relationship between both of parameters, and have suggestions of how to adjust competition parameters with each kind requirement of different conditioning by analyzing the result of simulations.
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Franscasmara, Raviqul Haidir, and 法蘭馬拉. "Optimizing Quality of Service (QoS) Parameters of Topics for Data Distribution Service (DDS) Systems." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/be3b5z.
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碩士<br>國立中央大學<br>資訊工程學系<br>107<br>Recent trends in net-centric systems motivate the development of information management capabilities that ensure the right information is delivered at the right place efficiently within specified time-range to satisfy the quality of service (QoS) requirements in many different environments. Data Distribution Service middleware offers a solution with the use of Quality of Service (QoS) Policies as a set of characters that drive a given behavior of the service so it may able to fulfill those requirements. QoS Policies has a wide range of attributes that can be applied to the Entity objects interacting within the system such as publisher, subscriber, topic etc. for example there are a total of 11 QoS Policies applicable to the Topic entity, however, it is difficult to find an optimal combination of these policies and their appropriate value. In this thesis we propose a way to optimize the performance (loss rate and latency) of a particular system design by using only the QoS Policy applicable to Topic entity. We use correlation analysis and the specification of QoS Policies for the collected dataset from our experiment to find the impact for each QoS policy toward the performance. The final result we found out that the combination of QoS Policies for a particular system design that able to optimize the performance of loss rate are Reliability & Durability QoS while to improve the performance of latency is Deadline QoS.
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Ong, Eng Hwee. "A generalized cooperative and cognitive radio resource management architecture for future wireless networks." Thesis, 2010. http://hdl.handle.net/1959.13/805169.
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Research Doctorate - Doctor of Philosophy (PhD)<br>Heterogeneity and convergence are two distinctive connotations of future wireless networks. Multiple access networks are expected to converge in a manner where heterogeneity can be exploited as an enabler to realize the Optimally Connected, Anywhere, Anytime vision of the International Telecommunication Union (ITU). This stimulates current trends toward the convergence of complementary heterogeneous access networks in an all-internet protocol (IP) core network and raises the importance of cooperation in such a multiple radio access technology (multi-RAT) environment. This thesis defines, develops, implements, and analyzes a novel generalized cooperative and cognitive RRM (CCRRM) architecture, anchored on the key principle of technology agnostic approach, to optimize radio resources usage, maximize system capacity, and improve quality of service (QoS) in future wireless networks. A novel measurement-based network selection technique, formulated based on mathematical framework, and terminal-oriented network-assisted (TONA) handover architecture are the main actors of this technology agnostic approach. In particular, QoS parameters estimation is a cornerstone of the generalized CCRRM architecture to facilitate technology abstraction and provide link layer cognition in an effort to realize seamless mobility in future wireless networks. By leveraging on the cooperative exchange of QoS context information over the converged all-IP core and novel concept of reactive QoS balancing (RQB) to achieve the end-to-end goal of promoting a QoS-balanced system, three RQB algorithms augmented with multi-domain cooperation techniques are developed to exploit the heterogeneity of access networks and distribute load opportunistically. Additionally, the radio resource management (RRM) design of the generalized CCRRM architecture is based on a network-terminal distributed decision making process, similar and compliant to the recent IEEE 1900.4 standard. Performance evaluation is conducted with comprehensive discrete event based simulation studies to gain insights of the promising intrinsic benefits associated with RQB under realistic, pragmatic scenarios. Furthermore, an elegant unified analytical model is developed to obtain the key performance metrics for the IEEE 802.11 distributed coordination function (DCF) infrastructure basic service set (BSS), under non-homogeneous conditions, by integrating a Markov chain model in conjunction with a finite queueing model. These performance metrics serve as bounds for reliable capacity analysis from which a model-based predictive QoS balancing (PQB) algorithm is developed as a benchmark for comparative performance studies with the proposed measurement-based RQB algorithm. The contributions of this thesis are not restricted to multiple access point (multi-AP) wireless local area network (WLAN), and the proof of concept is validated based on a heterogeneous multi-AP WLAN where appropriate. Moreover, conditions under which the generalized CCRRM architecture provides abstraction from underlying technologies and stays relevant to future IP-based multi-RAT environment have been established.
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Chang, Chih-Sheng, and 張智勝. "Sustainable-Cell-Rate Usage Parameter Control for QoS-Controlled High-Speed Network." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/81172969096123456121.
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碩士<br>國立交通大學<br>電信工程系<br>87<br>In this thesis, we first propose two intelligent TS-UPCs, which are conjunctions of the TS (traffic shaper) and the UPC (usage parameter controller) for sustainable-cell-rate usage parameter control in QoS-Controlled High-Speed Networks. One is the fuzzy TS-UPC, which is composed of the fuzzy leaky bucket; the other is neural fuzzy TS-UPC,
which is composed of the neural fuzzy leaky bucket. The fuzzy/neural fuzzy increment controllers (FIC/NFIC), which are incorporated with the conventional leaky bucket algorithm in fuzzy/neural fuzzy leaky bucket
algorithm, properly choose the long-term mean cell rate and the short-term mean cell rate as input variables and intelligently compute to determine the increment value. Three performance measures such as
selectivity, responsiveness, and queueing delay are considered. The intelligent fuzzy leaky bucket algorithms can have performance better than the conventional leaky bucket algorithm. And the neural fuzzy leaky
bucket algorithm outperforms the fuzzy leaky bucket algorithm.
Next we propose two types of neural fuzzy penalty schemes for punishing SCR-violating connections -- the neural fuzzy linear penalty scheme and the it neural fuzzy nonlinear penalty scheme, which impose an additional cell
dropping probability onto the cell dropping probability of a violating connection experienced at UPC. The neural fuzzy linear penalty scheme introduces a penalty control algorithm within the neural fuzzy leaky bucket algorithm employed by UPC, enabling the neural fuzzy leaky bucket algorithm to drop the conforming cells of a violating connection as a
punishment, whereas the neural fuzzy nonlinear penalty scheme introduces an increment function controller (IFC) within the neural fuzzy leaky bucket algorithms employed by both neural fuzzy TS and neural fuzzy UPC.
IFC adjusts the increment to make the connection's violation degree worse than the neural fuzzy leaky bucket in neural fuzzy UPC, and as a consequence, cells will be dropped more than should have originally. Simulation results show that the neural fuzzy penalty schemes are almost identical to the ideal cell loss ratio in selectivity. And theb neural
fuzzy penalty schemes have great performance in responsiveness and in mean queueing delay.
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Venâncio, Rui Miguel Morgado. "Micrometastasis detection guidance by whole-slide image texture analysis in colorectal lymph nodes correlated with QUS parameters." Master's thesis, 2016. http://hdl.handle.net/10316/32150.
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Dissertação de Mestrado em Engenharia Biomédica apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.<br>O cancro ´e uma doen¸ca que afeta milh˜oes por todo o mundo e uma identifica¸c˜ao
correta de gˆanglios linf´aticos pr´oximos do tumor prim´ario, que contenham regi˜oes
metast´aticas ´e de extrema importˆancia para um correto gerenciamento dos pacientes.
A avalia¸c˜ao histopatol´ogica ´e o ´unico m´etodo aceite para fazer essa identifica¸c˜ao.
Novas t´ecnicas emergentes como os ultrassons quantitativos podem ajudar nessa
identifica¸c˜ao, detetando regi˜oes metast´aticas no gˆanglio linf´atico antes mesmo de o
cortar. Propomos e avaliamos dois m´etodos para analisar e identificar automaticamente regi˜oes suspeitas que contenham met´astases em lˆaminas histopatol´ogicas
digitalizadas em alta resolu¸c˜ao, guiando o patologista em dire¸c˜ao `as regi˜oes suspeitas e classificando os gˆanglios como metast´aticos ou n˜ao-metast´aticos. O primeiro
m´etodo, ´e um m´etodo convencional de an´alise de texturas e o segundo ´e baseado
na aprendizagem profunda. Utilizando o m´etodo mais convencional particip´amos
numa competi¸c˜ao europeia chamada CAMELYON16. Esta competi¸c˜ao tinha duas
avalia¸c˜oes. Os m´etodos de textura utilizados foram as matrizes de coocorrˆencia de
n´ıveis de cinzento e medidas de energia de texturas de Laws. Os parˆametros de
textura ser˜ao utilizados para tentar encontrar rela¸c˜oes entre os ultrassons quantitativos e a histopatologia. Para a aprendizagem profunda utilizamos uma rede bem
documentada chamada VGG16. Imagens digitalizadas de lˆaminas histol´ogicas de 44
gˆanglios foram utilizadas. Para avaliar os m´etodos foram desenhadas curvas ROC e
F-Scores s˜ao calculados. Como resultados, obtivemos uma ´area sob a curva de 0.986
e um F-Score de 91.67 para o m´etodo mais convencional. Para a aprendizagem
profunda obtivemos uma ´area sob a curva e um F-score igual a 1.0. Na competi¸c˜ao
fic´amos em ´ultimo numa avalia¸c˜ao e em pen´ultimo na outra. Para finalizar, n˜ao foi
poss´ıvel encontrar nenhuma correla¸c˜ao entre os ultrassons e a histologia.<br>Cancer is a disease that affects millions worldwide and accurate determination of
whether lymph nodes (LNs) near the primary tumor contain metastatic foci is of
critical importance for proper patient management. Histopathological evaluation is
the only accepted method to make that determination. New emerging techniques like
quantitative ultrasound (QUS) may help in the determination by detect metastatic
regions in the LN before cutting it. We propose and evaluate two methods to
automatically analyze and identify suspicious regions for metastatic foci in highresolution digitized histopathological slides (whole-slide images (WSI)) to helping
the guidance of the pathologist towards cancer-suspicious regions and to classify LNs
as metastatic or non-metastatic. The first method is a conventional texture-based
method and the second one is based in deep convolutional neural networks (DCNNs). We have participated in the CAMELYON16 challenge with the conventional
method. The texture methods used are based on gray-level co-occurrence matrices
(GLCM) and Laws’ energy texture measures, which parameters will be used for
find correlations with the QUS. As DCNN we used a known network called VGG16.
Whole slide images (WSIs) of 44 lymph nodes (LNs) were used. For evaluate both
methods Receiver Operating Characteristic (ROC) curves were drawn. For the most
conventional method we obtained an Area Under the Curve (AUC) of 0.986 and a
F-Score of 91.67. For the CNN based method we obtained an AUC and a F-Score
of 1.0. The challenge had 2 evaluations, and we came last in one and second-to-last
in the second. We could not find any correlation between the ultrasounds and the
histology.
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Sikiotis, Lucas. "Adjustment of default parameters in the Quick Response System package (QRS II) for developing communities in ORMET." Thesis, 2014. http://hdl.handle.net/10210/10721.
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M.Ing. (Transportation)<br>This reseach focused on a quick response transportation planning software package called QRS II which was developed by A J Horowitz at the Centre for Urban Transportation Studies, University of Wisconsin, United states of America. The programme achieves its quick response by incorporating, inter alia, a large number of default parameters within its formulation. Several of these parameters define the typical travel characteristics of the population within a study area and as such, suggest a particular socioeconomic, political, cultural and behavioral profile as existing in that area. These typical conditions may be representative of the behavior in many areas in the United States but may not adequately reflect conditions beyond that. This study has set out to determine whether the default parameters used in QRS II are different to those that would be appropriate in Black towns in areas such as the East Rand Metropolitan Transport Area (ORMET) in South Africa. Local parameter values were identified and compared with the default values in QRS II. It was found that these values were significantly different. More research is required before QRS II can be considered fully adapted to conditions in Black urban areas within a Metropolitan area such as ORMET. However, the new values suggested in this study will go a long way to improving the appropriateness of QRS II applications in South Africa.
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Winkler, Ilka. "Untersuchungen spezieller immunologischer Parameter und Veränderung der Mikrozirkulation bei postoperativen geriatrischen Patienten in der Rekonvaleszenzphase vor und unter der Therapie mit Iscador QuS /." 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016235877&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Fago, Dorothea Cornelia [Verfasser]. "Comparison of the dual X-ray absorptiometry (DEXA) with the quantitative ultrasound (QUS) at the Os calcaneus with special consideration of drugs, labatory [laboratory] parameters and fractures = Vergleich der dualen Röntgenabsorptiometrie (DEXA) mit dem quantitativen Ultraschall (QUS) am Os calcaneus mit spezieller Betrachtung anhand von Medikamenten, Laborparametern und Frakturen / vorgelegt von Fago, Dorothea Cornelia, geb. Pinkowski." 2009. http://d-nb.info/100187563X/34.
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