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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Distributed state estimation using phasor measurement units (PMUs)for a system snapshot

Tuku, Woldu January 1900 (has links)
Master of Science / Department of Electrical and Computer Engineering / Noel N. Schulz / As the size of electric power systems are increasing, the techniques to protect, monitor and control them are becoming more sophisticated. Government, utilities and various organizations are striving to have a more reliable power grid. Various research projects are working to minimize risks on the grid. One of the goals of this research is to discuss a robust and accurate state estimation (SE) of the power grid. Utilities are encouraging teams to change the conventional way of state estimation to real time state estimation. Currently most of the utilities use traditional centralized SE algorithms for transmission systems. Although the traditional methods have been enhanced with advancement in technologies, including PMUs, most of these advances have remained localized with individual utility state estimation. There is an opportunity to establish a coordinated SE approach integration using PMU data across a system, including multiple utilities and this is using Distributed State Estimation (DSE). This coordination will minimize cascading effects on the power system. DSE could be one of the best options to minimize the required communication time and to provide accurate data to the operators. This project will introduce DSE techniques with the help of PMU data for a system snapshot. The proposed DSE algorithm will split the traditional central state estimation into multiple local state estimations and show how to reduce calculation time compared with centralized state estimation. Additionally these techniques can be implemented in micro-grid or islanded system.
2

Design Space Exploration of DNNs for Autonomous Systems

Duggal, Jayan Kant 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Developing intelligent agents that can perceive and understand the rich visualworld around us has been a long-standing goal in the field of AI. Recently, asignificant progress has been made by the CNNs/DNNs to the incredible advances& in a wide range of applications such as ADAS, intelligent cameras surveillance,autonomous systems, drones, & robots. Design space exploration (DSE) of NNs andother techniques have made CNN/DNN memory & computationally efficient. Butthe major design hurdles for deployment are limited resources such as computation,memory, energy efficiency, and power budget. DSE of small DNN architectures forADAS emerged with better and efficient architectures such as baseline SqueezeNetand SqueezeNext. These architectures are exclusively known for their small modelsize, good model speed & model accuracy.In this thesis study, two new DNN architectures are proposed. Before diving intothe proposed architectures, DSE of DNNs explores the methods to improveDNNs/CNNs.Further, understanding the different hyperparameters tuning &experimenting with various optimizers and newly introduced methodologies. First,High Performance SqueezeNext architecture ameliorate the performance of existingDNN architectures. The intuition behind this proposed architecture is to supplantconvolution layers with a more sophisticated block module & to develop a compactand efficient architecture with a competitive accuracy. Second, Shallow SqueezeNextarchitecture is proposed which achieves better model size results in comparison tobaseline SqueezeNet and SqueezeNext is presented. It illustrates the architecture is xviicompact, efficient and flexible in terms of model size and accuracy.Thestate-of-the-art SqueezeNext baseline and SqueezeNext baseline are used as thefoundation to recreate and propose the both DNN architectures in this study. Dueto very small model size with competitive model accuracy and decent model testingspeed it is expected to perform well on the ADAS systems.The proposedarchitectures are trained and tested from scratch on CIFAR-10 [30] & CIFAR-100[34] datasets. All the training and testing results are visualized with live loss andaccuracy graphs by using livelossplot. In the last, both of the proposed DNNarchitectures are deployed on BlueBox2.0 by NXP.
3

Network partitioning techniques based on network natural properties for power system application

Alkhelaiwi, Ali Mani Turki January 2002 (has links)
In this thesis, the problem of partitioning a network into interconnected sub-networks is addressed. The goal is to achieve a partitioning which satisfies a set of specific engineering constraints, imposed in this case, by the requirements of the decomposed state-estimation (DSE) in electrical power systems. The network-partitioning problem is classified as NP-hard problem. Although many heuristic algorithms have been proposed for its solution, these often lack directness and computational simplicity. In this thesis, three new partitioning techniques are described which (i) satisfy the DSE constraints, and (ii) simplify the NP-hard problem by using the natural graph properties of a network. The first technique is based on partitioning a spanning tree optimally using the natural property of the spanning tree branches. As with existing heuristic techniques, information on the partitioning is obtained only at the end of the partitioning process. The study of the DSE constraints leads to define conditions of an ideal balanced partitioning. This enables data on the balanced partitioning to be obtained, including the numbers of boundary nodes and cut-edges. The second partitioning technique is designed to obtain these data for a given network, by finding the minimum covering set of nodes with maximum nodal degree. Further simplification is then possible if additional graph-theoretical properties are used. A new natural property entitled the 'edge state phenomenon' is defined. The edge state phenomenon may be exploited to generate new network properties. In the third partitioning technique, two of these, the 'network external closed path' and the 'open internal paths', are used to identify the balanced partitioning, and hence to partition the network. Examples of the application of all three methods to network partitioning are provided.
4

Conception faible consommation d'un système de détection de chute / Low power architecture for fall detection system

Nguyen, Thi Khanh Hong 18 November 2015 (has links)
De nos jours, la détection de chute est un défi pour la santé, notamment pour la surveillance des personnes âgées. Le but de cette thèse est de concevoir un système de détection de chute basée sur une surveillance par caméra et d’étudier les aspects algorithmiques et architecturaux. Notre système se compose de quatre modules : la segmentation d’objet, le filtrage, l’extraction de caractéristiques et la reconnaissance qui permettent en plus de la détection de chute d’identifier leur type afin de définir un niveau d’alerte. En premier lieu, différents algorithmes ont été étudiés et comparés comme le Background Subtraction-Neural Network; le Background Subtraction-Template Matching (BGS-TM); le Background Subtraction-Hidden Markov Model ; et le Gaussian Mixture Model. Le BGS/TM présentant le meilleur taux de reconnaissance a alors été retenu. Une nouvelle base de donnée DTU-HBU a été construite et classifiée selon différentes actions : chute, non-chute (assis, couché, rampant, etc.) selon trois angles de caméra (face, côtés et de biais). Le second objectif fut de définir une méthode de conception permettant de sélectionner les architectures présentant la meilleure performance. Un premier travail fut de définir des modèles de la consommation et du temps d’exécution pour différentes cibles (processeur, FPGA). A titre d’exemple, la plateforme ZYNQ a été considérée. Les modèles proposés présentent un taux erreur inférieur à 3,5%. Une méthodologie de conception DSE basée sur deux techniques de parallélisme (Intra-task et inter-task) et couplant le taux de reconnaissance (ACC) a été définie. Les résultats obtenus montrent que l’ACC atteint 98,3% pour une énergie de 29,5 mJ/f. / Nowadays, fall detection is a major challenge in the public health care domain, especially for the elderly living alone and rehabilitants in hospitals. This thesis presents an exploration for a Fall Detection System based on camera under an algorithmic and architectural point of view. Our system includes four modules: Object Segmentation, Filter, Feature Extraction and Recognition and give an urgent alarm for detecting different kinds of fall. Firstly, different algorithms for the Fall Detection System are proposed and compared the efficiency among Background Subtraction-Neural Network, Background Subtraction-Template Matching (BGS/TM), Background Subtraction-Hidden Markov Model, and Gaussian Mixture Model. Therefore, the selected BGS/TM with 91.67% (Recall), 100% (Precision) and 95.65% (Accuracy) will be implemented on ZYNQ platform. Moreover, a DUT-HBU database which is classified with different actions: fall, non-fall in three camera directions is used to evaluate the efficiency of this system. Secondly, the aim is to explore low cost architectures for this system, new power consumption and execution time models for processor core and FPGA are defined according to the different configurations of architecture and applications. The error rates of the proposed models don’t exceed 3.5%. The models are then extended to hardware/software architectures to explore low cost architecture by defining a suitable Design Space Exploration methodology. Two techniques for parallelization which are based on intra-task and inter-task static scheduling are applied with the aim to enhance the accuracy and the power consumption of this system reaches 98.3% with energy per frame of 29.5mJ/f.
5

Online scheduling for real-time multitasking on reconfigurable hardware devices

Wassi-Leupi, Guy January 2011 (has links)
Nowadays the ever increasing algorithmic complexity of embedded applications requires the designers to turn towards heterogeneous and highly integrated systems denoted as SoC (System-on-a-Chip). These architectures may embed CPU-based processors, dedicated datapaths as well as recon gurable units. However, embedded SoCs are submitted to stringent requirements in terms of speed, size, cost, power consumption, throughput, etc. Therefore, new computing paradigms are required to ful l the constraints of the applications and the requirements of the architecture. Recon gurable Computing is a promising paradigm that provides probably the best trade-o between these requirements and constraints. Dynamically recon gurable architectures are their key enabling technology. They enable the hardware to adapt to the application at runtime. However, these architectures raise new challenges in SoC design. For example, on one hand, designing a system that takes advantage of dynamic recon guration is still very time consuming because of the lack of design methodologies and tools. On the other hand, scheduling hardware tasks di ers from classical software tasks scheduling on microprocessor or multiprocessors systems, as it bears a further complicated placement problem. This thesis deals with the problem of scheduling online real-time hardware tasks on Dynamically Recon gurable Hardware Devices (DRHWs). The problem is addressed from two angles : (i) Investigating novel algorithms for online real-time scheduling/placement on DRHWs. (ii) Scheduling/Placement algorithms library for RTOS-driven Design Space Exploration (DSE). Regarding the first point, the thesis proposes two main runtime-aware scheduling and placement techniques and assesses their suitability for online real-time scenarios. The first technique discusses the impact of synthesizing, at design time, several shapes and/or sizes per hardware task (denoted as multi-shape task), in order to ease the online scheduling process. The second technique combines a looking-ahead scheduling approach with a slots-based recon gurable areas management that relies on a 1D placement. The results show that in both techniques, the scheduling and placement quality is improved without signi cantly increasing the algorithm time complexity. Regarding the second point, in the process of designing SoCs embedding recon gurable parts, new design paradigms tend to explore and validate as early as possible, at system level, the architectural design space. Therefore, the RTOS (Real-Time Operating System) services that manage the recon gurable parts of the SoC can be re fined. In such a context, gathering numerous hardware tasks scheduling and placement algorithms of various complexity vs performance trade-o s in a kind of library is required. In this thesis, proposed algorithms in addition to some existing ones are purposely implemented in C++ language, in order to insure the compatibility with any C++/SystemC based SoC design methodology.
6

Une approche système pour l'estimation de la consommation de puissance des plateformes MPSoC / System-Level Power Estimation Methodology for MPSoC based Platforms

Rethinagiri, Santhosh Kumar 14 March 2013 (has links)
Avec l'essor des nouvelles technologies d'intégration sur silicium submicroniques, la consommation de puissance dans les systèmes sur puce multiprocesseur (MPSoC) est devenue un facteur primordial au niveau du flot de conception. La prise en considération de ce facteur clé dès les premières phases de conception, joue un rôle primordial puisqu'elle permet d'augmenter la fiabilité des composants et de réduire le temps d'arrivée sur le marché du produit final. / Shifting the design entry point up to the system-level is the most important countermeasure adopted to manage the increasing complexity of Multiprocessor System on Chip (MPSoC). The reason is that decisions taken at this level, early in the design cycle, have the greatest impact on the final design in terms of power and energy efficiency. However, taking decisions at this level is very difficult, since the design space is extremely wide and it has so far been mostly a manual activity. Efficient system-level power estimation tools are therefore necessary to enable proper Design Space Exploration (DSE) based on power/energy and timing.
7

Design space exploration using HLS in relation to code structuring / Utforskning av design space med HLS i förhållande till kodstrukturering

Das, Debraj January 2022 (has links)
High Level Synthesis (HLS) is a methodology to translate a model developed in a high abstraction layer, e.g. C/C++/SystemC, that describes the algorithm into a Register-Transfer level (RTL) description like Verilog or VHDL. The resulting RTL description from the translation is subject to multiple user-controlled directives and an internal design space exploration algorithm specific to the toolchain used. HLS allow designers to focus on the behaviour of the design at a higher abstraction compared to the behavioural modelling available within the Hardware Description Language (HDL) as the compiler decides the movement of data and timing in the resulting design. Ericsson uses a legacy Advanced Peripheral Bus (APB) like interface called Memory/Register Interface (MIRI) interface for data movement in a subsystem of one of their Application-Specific Integrated Circuit (ASIC). The thesis attempts to upgrade the protocol to the more performant ARM Advanced Microcontroller Bus Architecture (AMBA) protocols’ Advanced High-performance Bus (AHB) or Advanced eXtensible Interface (AXI) interfaces. SystemC provides a host of functionalities to define the complete behaviour of the circuit at a high level of abstraction. This thesis will explore the effect of the structuring SystemC models on their synthesis, and perform design space exploration to understand the best design methodology to adopt in a SystemC model design and compare the models based on the final synthesis metrics like area, timing, and register counts. The toolchain for the thesis will be the Stratus HLS compiler developed by Cadence. Stratus supports all synthesizable constructs of SystemC. Most HLS research focuses on improving Design Space Exploration algorithms used internally in the HLS tools. However, designers can utilize algorithm structuring to provide the HLS engines with a better starting point. In this thesis, the Stratus toolchain will be used to experiment with different models with equivalent behaviour and performance. Thereafter, extract which constructs used in the models are optimal for allowing the internal design space exploration algorithm to perform in the best way possible. / HLS är en metod för att översätta en modell utvecklad på hög abstraktionsnivå t.ex. C/C++/SystemC som beskriver algoritmen på registeröverföringsnivå (RTL) som Verilog eller VHDL. Den resulterande RTL-beskrivningen utsätts för flera användarkontrollerade direktiv och en intern Design Space Exploration (DSE) algoritm, vilken är specifik för den verktygskedja som används. Detta gör det möjligt för en designer att fokusera på konstruktion beteende på en högre abstraktionsnivå jämfört med den beteendemodellering som finns tillgänglig inom det hårdvarubeskrivande språket (HDL:en) när kompilatorn bestämmer tidpunkten för utbytet av data i den resulterande designen. Ericsson använder ett äldre gränssnitt för Advanced Peripheral Bus (APB) som kallas Memory/Register Interface (MIRI), vilket är ett gränssnitt för utbyte av data i ett delsystem i en av deras Application-Specific Integrated Circuit (ASIC:ar). Avhandlingen försöker uppgradera protokollet till ett av de det mer högpresterande ARM Advanced Microcontroller Bus Architecture – protokollen Advanced High-Performance Bus (AHB) eller Advanced eXtensible Interface (AXI). SystemC tillhandahåller en mängd funktioner för att definiera kretsens fullständiga beteende vid en hög abstraktionsnivå. Denna avhandling utforskar effekten av strukturerade SystemC-modeller och deras syntesresultat samt konstruktionsrymden, för att förstå den bästa designmetodiken i ett SystemC-modelleringsdesignflöde och jämföra modellerna baserade på de slutliga syntesmätvärdena som storlek, timing, etc. Verktygskedjan för avhandlingen kommer att vara Stratus HLS -kompilatorn som utvecklats av Cadence. Stratus stöder alla syntetiserbara konstruktioner av SystemC. HLS-forskningen fokuserar främst på att förbättra Design Space Exploration, dvs de algoritmer som används internt i HLS-verktygen för att komma fram till lösningar. För att ge HLS -motorerna en bättre utgångspunkt. I denna avhandling kommer Stratus att användas för att utvärdera olika modeller med ekvivalent beteende och nästan samma prestanda efter Syntes, för att komma fram till vilka konstruktioner är optimala för att den interna DSE-algoritmen skall fungera bäst.
8

The Role of Polyadenylation in Human Papillomavirus Type 16 Late Gene Expression

Öberg, Daniel January 2005 (has links)
<p>High-risk type human papillomaviruses (HPVs) are associated with cancer. HPVs are strictly epitheliotropic and infect basal cell layers, establishing a life cycle strongly linked to the differentiation stage of the infected cells. The viral capsid late genes, L2 and L1, are only expressed in terminally differentiated epithelium. Late gene expression involves regulation of most gene processing events including transcription, splicing, polyadenylation, mRNA stability and translation. </p><p>Both L2 and L1 have elements present in the open reading frames (ORFs) negatively affecting mRNA levels and translation. The negative elements in L1 were mapped to the first 514 nucleotides, with the strongest inhibitory effect located in the first 129 nucleotides. The negative elements in the L2 sequence were concentrated in two locations on the gene. Both genes were mutated by changing the nucleotide sequence while retaining the amino acid sequence. Mutating the first 514 nucleotides in L1 deactivated the negative elements while the entire L2 gene had to be mutated to achieve the same result. The L2 protein was found to localise the L1 protein into a punctuated pattern in the nucleus.</p><p>In the HPV-16 genome the negative elements reside in regions important for regulation of polyadenylation and splicing, critical for late gene expression. By exchanging parts of the L2 gene in subgenomic constructs with the corresponding mutant sequence we show that certain features of the L2 elements direct splicing to the L1 splice acceptor, and also regulate the efficiency of the early polyadenylation site. Cumulative binding of hnRNP H to the L2 mRNA gradually increased polyadenylation efficiency. Most interestingly, hnRNP H levels were downregulated in more differentiated epithelial cells. </p><p>Elucidation of how expression of the immunogenic late proteins is regulated would be greatly beneficial in prevention and treatment of HPV infection and thereby cancer.</p>
9

The Role of Polyadenylation in Human Papillomavirus Type 16 Late Gene Expression

Öberg, Daniel January 2005 (has links)
High-risk type human papillomaviruses (HPVs) are associated with cancer. HPVs are strictly epitheliotropic and infect basal cell layers, establishing a life cycle strongly linked to the differentiation stage of the infected cells. The viral capsid late genes, L2 and L1, are only expressed in terminally differentiated epithelium. Late gene expression involves regulation of most gene processing events including transcription, splicing, polyadenylation, mRNA stability and translation. Both L2 and L1 have elements present in the open reading frames (ORFs) negatively affecting mRNA levels and translation. The negative elements in L1 were mapped to the first 514 nucleotides, with the strongest inhibitory effect located in the first 129 nucleotides. The negative elements in the L2 sequence were concentrated in two locations on the gene. Both genes were mutated by changing the nucleotide sequence while retaining the amino acid sequence. Mutating the first 514 nucleotides in L1 deactivated the negative elements while the entire L2 gene had to be mutated to achieve the same result. The L2 protein was found to localise the L1 protein into a punctuated pattern in the nucleus. In the HPV-16 genome the negative elements reside in regions important for regulation of polyadenylation and splicing, critical for late gene expression. By exchanging parts of the L2 gene in subgenomic constructs with the corresponding mutant sequence we show that certain features of the L2 elements direct splicing to the L1 splice acceptor, and also regulate the efficiency of the early polyadenylation site. Cumulative binding of hnRNP H to the L2 mRNA gradually increased polyadenylation efficiency. Most interestingly, hnRNP H levels were downregulated in more differentiated epithelial cells. Elucidation of how expression of the immunogenic late proteins is regulated would be greatly beneficial in prevention and treatment of HPV infection and thereby cancer.
10

A critical analysis of Tanzanian corporate governance regulation and its impact on foreign investment

Nyaki, Judith V. January 2013 (has links)
Magister Legum - LLM / The main objective of this study is to review the legal and regulatory framework of corporate governance in Tanzania with the focus on corporate governance laws and regulations. The study is intended to discuss the main legal and regulatory framework in Tanzania which plays a part in the corporate governance. The Companies Act No. 12 of 2002 will be reviewed in order to establish which corporate governance principles are provided and to what extent they are effective. The capital markets and securities laws, guidelines on corporate governance in Tanzania with a focus on the listing requirements and other regulations applied at the DSE will also be reviewed in order to establish their effectiveness in attracting investors to the market. Given the comparative value of South Africa and Kenya in SADC and EAC respectively, this work will also discuss the legal and regulatory framework of corporate governance in Kenya and South Africa and compare with those in Tanzania in areas such as shareholders rights; stakeholder’s right; board control and effectiveness and the effectiveness of compliance. Such comparative analysis is done in order to single out areas of focus in legal and regulatory framework in corporate governance law such as companies’ law and stock market and security laws in Tanzania.

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