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1
Stojanovski, Todor. "Bus rapid transit (BRT) and transitoriented development (TOD) : How to transform and adjust the Swedish cities for attractive bus systems like BRT? What demands BRT?" Licentiate thesis, KTH, Trafik och logistik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-128526.
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Bus rapid transit (BRT) is an innovative bus system with sophisticated vehicles and inflexible busways integrated in the cities, high capacity and high quality, high speed and frequency, distinctive image and comfort. Many in Sweden believe that is impossible to introduce BRT, even though the Swedish towns and cities can benefit from the image, speed and frequency that BRT symbolizes. The archipelago-like urbanization, urban sprawl and the uncompetitive journey times of public transportation compared with the private car are identified as main obstacles. New questions emerged: Is it possible to transform and adjust the Swedish towns and cities for BRT? What demands BRT? How is transit-oriented development (TOD) applicable in a Swedish context as a policy to integrate cities and BRT? In this licentiate thesis I investigate the interrelationship between bus transportation and neighborhoods, between BRT and urban form as well as the possibilities to introduce busways and BRT, to trigger TOD and to transform the Swedish towns and cities for BRT. Much has been written about BRT, but seldom by architects or urban planners and designers. BRT and TOD are seen though urban form and processes of urbanization within a morphological tradition established by Kevin Lynch. BRT is represented by paths and nodes that disperse distinctive attractiveness pattern of desirability cores that shape neighborhoods as districts. TOD is about synchronizing the everyday urban life with public transportation systems. BRT-TOD is defined as a policy to recognize desirability cores spread by the different infrastructures of BRT and promote development of urban form within their attractiveness pattern at urban and regional scale. BRT-TOD is discussed as a concept of BRT metropolis in context of the urbanization of Swedish towns and cities. TOD is defined morphologically as public transport cities. A public transport city is a city that in its development adapted to specific public transportation systems. TOD is nothing new in Europe or Sweden. To find regularities of the effect of public transportation systems on cities I do a historical overview of the Swedish towns and cities. In the end the position of bus and BRT, public transport cities and TOD and possibilities of future urban transformation of the smaller and larger Swedish cities towards BRT metropolises are discussed in context of today’s “‘system’ of automobility” and widespread car society and the emerging knowledge society and its postmodern fringes of urbanization.QC 20130917
2
Guzman, Jaramillo Alvaro Nicolas. "Understanding the role of power during the implementation of BRT systems." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/20824/.
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This research is about power. It is completely immersed in modern societies, reflections on power have not settled its definition. Regardless of centuries of considerations about power, there is still much to learn about its exercise. For decades, power has been analysed by scholars all over the world; however, transport planners have avoided issues concerning power. This dissertation focuses on the use of power during planning and implementation processes of two Bus Rapid Transit Systems; one in Quito, Ecuador, and another in Cambridge, England. Using a multimethod phronetic approach, this research examines how decisions were made for the implementation of BRT in the selected case studies. Phronetic methodology aims to explain social phenomena by piecing together large and small details that shape the context of events; in this case, existing planning documentation and the narratives of key stakeholders and decision-makers —such as former Mayors, Council Members, and Heads of Transport Departments— were used to understand the reasons behind the adoption of bus systems. Despite the contextual differences of geography, population, and political and administrative terms between Quito and Cambridge, there are key themes found in both case studies. Solving congestion and improving economic growth is a key motivation for the implementation of the systems in both cases. A complex network of actors is formed during the planning processes of BRT systems that shape the way decisions are made. In both cases, an isolated group of actors that lack the opportunity to exercise power was also identified. A sophisticated mixture of power mechanisms were discovered, which contained actors that had more experience, training and opportunities to exercise power. The findings of the analysis of power in Quito and Cambridge suggest that stakeholders with opportunities to exercise power —from the beginning— are also actors with more opportunities to influence the final uptake of the systems. Planners interested in participatory processes need to focus efforts to involve different communities as early as possible in the planning processes. The inclusion of communities does not guarantee that their needs and objectives will be incorporated into the planning process. A set of power mechanisms need to be developed by all members involved in the process. An early participation of these communities can help focus planning on solving people’s needs rather than the implementation of a specific scheme.
3
Santos, Paula Manoela dos. "Método de calibração de um modelo veículo seguidor para BRT e ônibus em corredor segregado." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/75917.
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O modelo veículo seguidor – ou car-following – é o coração dos softwares de simulação microscópica de tráfego. Quando bem calibrados, esses softwares são capazes de replicar a realidade em ambiente controlado. Ainda hoje há uma resistência quanto à calibração do modelo veículo seguidor e, mesmo que muitos trabalhos relatem formas de realizá-la, são escassas as referências na literatura sobre calibração utilizando dados de sistemas ônibus. Este trabalho consiste na elaboração de um método de calibração do modelo veículo seguidor de Gipps, combinado ao modelo de aceleração linear, para a replicação da operação de ônibus em corredores exclusivos. A elaboração do método iniciou com uma revisão dos principais modelos veículo seguidor e uma posterior avaliação dos modelos GHR e de Gipps para manobras típicas de sistemas ônibus. A seguir elaborou-se o procedimento de calibração utilizando coleta de dados por meio de filmagens da operação dos ônibus em corredores e da extração dos dados utilizando uma ferramenta de reconhecimento de imagem. O método das coordenadas retangulares foi utilizado para corrigir a paralaxe. Concomitante às filmagens analisou-se visualmente a ocupação dos ônibus para que as taxas de aceleração e desaceleração dos ônibus pudessem ser diferenciadas conforme o nível de ocupação. A calibração foi realizada através da comparação da distância percorrida pelos veículos ao longo do tempo e as correspondentes modeladas. Os resultados para taxas de aceleração e desaceleração obtidas a partir de dados coletados em Curitiba evidenciam a validade do procedimento. A simplicidade do método desenvolvido é uma característica importante, pois permite a replicação em outros ambientes sem a necessidade de equipamentos sofisticados.The car-following model is the heart of the traffic simulation software and it is able to replicate real traffic conditions in a controlled environment when properly calibrated. Still today there is resistance on the car-following model calibration and, even though many papers report calibration forms of this model, there are scarce references in the literature about calibration using bus systems data. This work is the development of a method for calibrating the Gipps car-following model, combined with the free linear acceleration model, for replication of buses operation in exclusive lanes. We initiated the method planning with a review of the main car-following model and evaluation of GHR and Gipps for typical bus systems maneuvers. In the next step we developed the calibration procedure using data collection through filming bus operation and drawing out data using a tool for image recognition. We used the rectangular coordinates method to parallax correction. We also visually analyzed the buses occupation simultaneously to filming, so bus acceleration and deceleration rates could be differentiated according to the occupancy level. Calibration was achieved by comparing the vehicle distance traveled over time and corresponding modeled. The results for acceleration and deceleration rates and speed desired values obtained from data collected in Curitiba demonstrate the validity of the procedure. An important feature of this method is the plainness, as it enables replication in other environments without the need for sophisticated equipment.
4
Ramirez-Bernal, Maria Fernanda. "How effective will a BRT system going to be in Santiago de Chile? Case studies." Cincinnati, Ohio : University of Cincinnati, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1203610888.
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Thesis (Master of Community Planning)--University of Cincinnati, 2008.Advisor: David Edelman J. (Committee Chair); Christopher Auffrey (Committee Co-Chair) Title from electronic thesis title page (viewed May 8, 2008). Includes abstract. Keywords: BRT; public transportation; transportation systems; Curitiba; Brazil; Bogota; Colombia; Santiago de Chile; Chile; developing countries Includes bibliographical references.
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Sousa, Lorena Cristina Faria de. "O conceito de urbanidade como ferramenta de análise da inserção urbana de sistemas BTR." Universidade Federal de Goiás, 2018. http://repositorio.bc.ufg.br/tede/handle/tede/9109.
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Solve the urban mobility in Brazilian ́s big cities is a necessary theme within the current urban planning, we must think of ways that people move through the urban fabric quickly and efficiently, within this scenario the prioritization of the public transportation through the insertion of systems BRT (Bus Rapid Transit or Bus Rapid Transit) that are usually used in an existing urban network, modifying the design of a street to receive resources through the segregation of traffic between vehicles and public transportation, has been implemented as a plausible and economically viable solution for cities. However, the focus on operational efficiency should not be the only approach to be taken. Performance must be a continuous system, continuing its role as the main public space within the city. From a non-governmental perspective of collective displacement, light infrastructure must also be provided. It is necessary that the series continue to be attractive and inviting to those who are circulating, which are urban to their users. Thus, a research presents in the area of the concept of urbanity and its dimensions and are tools of evaluation of the urbanity of spaces. Understanding that urbanity is a way to become your own unit, such as accessibility, security in access spaces, readability, vitality, among other aspects.
Resolver a mobilidade urbana nas grandes cidades brasileiras é um temática em pauta e necessária dentro do planejamento urbano atual, é preciso repensar as formas de as pessoas se deslocarem pelo tecido urbano de maneira rápida e eficiência, dentro deste cenário a priorização do transporte coletivo através da inserção de sistemas BRT (Bus Rapid Transit ou transporte Rápido por Ônibus) que consiste em aproveitar a malha urbana já existente, modificando o desenho de ruas para receber tal infraestrutura por meio da segregação do trafego entre veículos particulares e otransporte público, vem sendo implementado como uma solução plausível e economicamente mais viável para as cidades. Entretanto o enfoque apenas na eficiência operacional não deve ser o único enfoque a ser dar. É preciso que as ruas onde este sistema seja inserido continuem prestando seu papel como principal espaço público dentro da cidade. Sob a perspectiva de que a as políticas de mobilidade não deve apenas oferecer velocidade de deslocamentos dentro do transporte coletivo, mas devem também oferecer que a rua onde estas infraestruturas estejam inseridas sejam também de qualidade. É necessário que estas ruas continuem sendo atrativas e convidativas para os que nela circulam, que ofereçam urbanidade aos seus usuários. Assim essa pesquisa se insere na investigação do conceito de urbanidade e suas dimensões e a propõe ferramentas de avaliação da urbanidade destes espaços. Entendendo que urbanidade é a forma com que o espaço público irá receber seus usuários, denota a hospitalidade do espaço por meio de suas qualidades físicas como a acessibilidade, a segurança viária nos deslocamentos a pé, a legibilidade, a vitalidade, entre outros aspectos.
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Peron, Luciano. "Contribuição metodológica para aplicação de prioridade semafórica condicional em corredores de ônibus." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-05112015-103715/.
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Esta pesquisa traz à discussão a implantação de Sistemas Inteligentes de Transportes (ITS), em particular a funcionalidade Transit Signal Priority (TSP), ou Prioridade Semafórica, como uma solução a ser considerada para melhorar o desempenho de um corredor de ônibus. Os dados do Sistema Integrado de Monitoramento (SIM) foram empregados para identificar os locais com maior retardamento no Corredor Campo Limpo - Rebouças- Centro em São Paulo e, selecionado um trecho crítico, foi elaborada uma rede de microssimulação no software PTV - Vissim. A aplicação da prioridade semafórica foi feita através do VISVAP, controlador de lógica externo, no qual foram escritas as condicionantes de prioridade. O TSP foi simulado em quatro cenários distintos e, os resultados obtidos permitiram concluir que as expectativas verificadas no referencial teórico (por exemplo: aumento da velocidade média dos ônibus e automóveis), puderam ser comprovadas e, além disso, a prioridade semafórica condicional foi capaz de reduzir os retardos inclusive nas vias transversais não priorizadas.This research brings to discussion the implementation of Intelligent Transportation Systems (ITS), particularly the Transit Signal Priority (TSP) feature as a solution to be considered to improve the performance of a bus corridor. Data from a Monitoring Integrated System (Sistema Integrado de Monitoramento - SIM) were used to identify most significant delay points at Campo Limpo - Rebouças- Centro Corridor in São Paulo and, after selected a critical stretch, it was developed a microsimulation with PTV Vissim software. The transit signal priority was made by VISVAP, external logic controller, in which were described the priority conditions. TSP was simulated in four different scenarios and, the obtained results have concluded that expectations examined in academic referencial (for example: increase in the average speed of buses and cars), could be confirmed, and, in addition, the transit signal priority was able to decrease delays in cross ways too (not prioritized).
7
Jansson, Herman. "Low-resource Language Question Answering Systemwith BERT." Thesis, Mittuniversitetet, Institutionen för informationssystem och –teknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-42317.
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The complexity for being at the forefront regarding information retrieval systems are constantly increasing. Recent technology of natural language processing called BERT has reached superhuman performance in high resource languages for reading comprehension tasks. However, several researchers has stated that multilingual model’s are not enough for low-resource languages, since they are lacking a thorough understanding of those languages. Recently, a Swedish pre-trained BERT model has been introduced which is trained on significantly more Swedish data than the multilingual models currently available. This study compares both multilingual and Swedish monolingual inherited BERT model’s for question answering utilizing both a English and a Swedish machine translated SQuADv2 data set during its fine-tuning process. The models are evaluated with SQuADv2 benchmark and within a implemented question answering system built upon the classical retriever-reader methodology. This study introduces a naive and more robust prediction method for the proposed question answering system as well finding a sweet spot for each individual model approach integrated into the system. The question answering system is evaluated and compared against another question answering library at the leading edge within the area, applying a custom crafted Swedish evaluation data set. The results show that the fine-tuned model based on the Swedish pre-trained model and the Swedish SQuADv2 data set were superior in all evaluation metrics except speed. The comparison between the different systems resulted in a higher evaluation score but a slower prediction time for this study’s system.
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Fors, Jonatan, and Annika Järnström. "När användaren kom bort." Thesis, Uppsala universitet, Institutionen för informatik och media, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-266877.
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Today's technological development means that organizations are constantly evolving. This means that the market, which the organizations operate in, is constantly changing and becoming more complex to interpret. This development increases the demand to forecast possible outcomes and receive real-time information from the operations – i.e., obtain the most accurate data for decision-support. To make this possible, organizations need so-called ‘decision support systems’; IT-tools that rapidly provide decision makers with information based on relevant data. To obtain the highest possible value from the systems, they must seamlessly integrate and interact with the organization. This study examines how decision support systems, organizations and users relate to each other in an organizational context. The aim is to provide an insight into the limitations and possibilities of human behaviour, technological development and organizational structure to create and enable relevant and effective decision support systems. The paper’s theoretical framework is based on Orlikowski’s (1992) structurational model. The empirical material consists of semi-structured interviews, which are analysed based on Orlikowski’s model. The results show that although there is a common understanding on how the different factors should interact in order for the decision support systems to function the respondents neglected their own influence as users of the systems.Dagens teknikutveckling medför att organisationer hela tiden utvecklas och förändras. Det i sin tur medför att den marknad organisationer agerar på förändras och blir alltmer komplex att tolka. Denna utveckling ökar efterfrågan att förutspå sannolika utfall, få information om verksamheten i realtid, kort sagt få ett korrekt beslutsunderlag. För att detta ska vara möjligt behövs IT-verktyg som snabbt kan förse beslutsfattare med underlag som grundar sig på relevanta data, så kallade beslutsstödsystem. För att få ut mesta möjliga värde från beslutsstödsystemen ställs höga krav på att de integreras och samverkar med organisationen. I studien undersöks hur beslutsstödsystem, organisationer och användare förhåller sig till varandra i en organisatorisk kontext. Målet är att ge en inblick i de begränsningar och möjligheter människors agerande, teknikens utveckling och organisationens struktur skapar för att möjliggöra relevanta och effektiva system för beslutsstöd. Studiens teoretiska ramverk tar sin utgångspunkt i Orlikowskis (1992) struktureringsmodell. Det empiriska materialet utgörs av semistrukturerade intervjuer som analyseras med utgångspunkt från Orlikowskis modell. Resultatet visar att även om det överlag finns en förståelse för hur olika faktorer bör samspela för att beslutsstödsystemen ska fungera, tonar respondenterna ner sin egen betydelse som användare av systemen.
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Kesen, Lokman. "Implementation Of An 8-bit Microcontroller With System C." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605653/index.pdf.
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In this thesis, an 8-bit microcontroller, 8051 core, is implemented using SystemC
programming language. SystemC is a new generation co-design language which is
capable of both programming software and describing hardware parts of a
complete system. The benefit of this design environment appears while developing
a System-on-Chip (SoC), that is a system consisting both custom hardware parts
and embedded software parts. SystemC is not a completely new language, but
based on C++ with some additional class libraries and extensions to handle
hardware related concepts such as signals, multi-valued logic, clock and delay
elements. 8051 is an 8 bit microcontroller which is widely used in industry for many
years. The 8051 core is still being used as the main controller in today&rsquos highly complex chips, such as communication and bus controllers. During the development cycles of a System-on-Chip, instead of using separate design environments for hardware and software parts, the usage of a unified co-design environment provides a better design and simulation methodology which also decreases the number of iterations at hardware software integration. In this work, an 8-bit 8051 microcontroller core and external memory modules are developed using SystemC that can be re-used in future designs to achieve more complex System-on-Chip&rsquo
s. During the development of the 8051 core, simulation results are analyzed at each step to verify the design from the very beginning of the work, which makes the design processes more structured and controlled and faster as a result.
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Li, Fangyan. "Simulation multi-moteurs multi-niveaux pour la validation des spécifications système et optimisation de la consommation." Thesis, Nice, 2016. http://www.theses.fr/2016NICE4008/document.
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Ce travail vise la modélisation au niveau système, en langage SystemC-AMS, et la simulation d'un émetteur-récepteur au standard Bluetooth Low Energy (BLE). L'objectif est d'analyser la relation entre les performances, en termes de BER et la consommation d'énergie du transceiver. Le temps de simulation d’un tel système, à partir de cas d’étude (use case) réaliste, est un facteur clé pour le développement d’une telle plateforme. De plus, afin d’obtenir des résultats de simulation le plus précis possible, les modèles « haut niveau » doivent être raffinés à partir de modèles plus bas niveau où de mesure. L'approche dite Meet-in-the-Middle, associée à la méthode de modélisation équivalente en Bande Base (BBE, BaseBand Equivalent), a été choisie pour atteindre les deux conditions requises, à savoir temps de simulation « faible » et précision des résultats. Une simulation globale d'un système de BLE est obtenue en intégrant le modèle de l'émetteur-récepteur dans une plateforme existante développée en SystemC-TLM. La simulation est basée sur un système de communication de deux dispositifs BLE, en utilisant différents scénarios (différents cas d'utilisation de BLE). Dans un premier temps nous avons modélisé et validé chaque bloc d’un transceiver BT. Devant le temps de simulation prohibitif, les blocs RF sont réécrits en utilisant la méthodologie BB, puis raffinés afin de prendre en compte les non-linéarités qui vont impacter le couple consommation, BER. Chaque circuit (chaque modèle) est vérifié séparément, puis une première simulation système (point à point entre un émetteur et un récepteur) est effectuéeThis work aims at system-level modelling a defined transceiver for Bluetooth Low energy (BLE) system using SystemC-AMS. The goal is to analyze the relationship between the transceiver performance and the accurate energy consumption. This requires the transceiver model contains system-level simulation speed and the low-level design block power consumption and other RF specifications. The Meet-in-the-Middle approach and the Baseband Equivalent method are chosen to achieve the two requirements above. A global simulation of a complete BLE system is achieved by integrating the transceiver model into a SystemC-TLM described BLE system model which contains the higher-than-PHY levels. The simulation is based on a two BLE devices communication system and is run with different BLE use cases. The transceiver Bit-Error-Rate and the energy estimation are obtained at the end of the simulation. First, we modelled and validated each block of a BT transceiver. In front of the prohibitive simulation time, the RF blocks are rewritten by using the BBE methodology, and then refined in order to take into account the non-linearities, which are going to impact the couple consumption, BER. Each circuit (each model) is separately verified, and then a first BLE system simulation (point-to-point between a transmitter and a receiver) has been executed. Finally, the BER is finally estimated. This platform fulfills our expectations, the simulation time is suitable and the results have been validated with the circuit measurement offered by Riviera Waves Company. Finally, two versions of the same transceiver architecture are modelled, simulated and compared
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Einicke, Garry A. "Random bit interleaving for trunk link encryption /." Title page, abstract and contents only, 1990. http://web4.library.adelaide.edu.au/theses/09EN/09ene35.pdf.
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Graf, Patrick Anthony. "Efficient bit encoding in backscatter wireless systems." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33946.
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As the size and power consumption of microelectronic circuits continues to decrease, passively-powered sensors promise to come to the forefront of commercial electronics. One of the most promising technologies that could realize this goal is backscatter sensing. Backscatter sensors could harvest power from and modulate data onto an impinging carrier waveform. Currently radio frequency identification (RFID) technology passively powers itself and transmits statically stored data. However, this technology has two major weaknesses: lack of resiliency against narrowband interference and slow data rates. Both of these issues could be detrimental in sensing applications. This thesis will lay out a method for addressing both of these weaknesses through a unique application of spread spectrum encoding. Instead of spread spectrum being viewed as the multiplication of an already encoded data sequence with a periodic pseudorandom sequence, each sequence could be viewed in an aperiodic manner, where a single period of a pseudorandom sequence represents a data symbol. In this manner, backscatter sensors not only benefit from the increased resiliency that spread spectrum provides, but also can have higher data rates, since multiple bits can be encoded on a single symbol and multiple nodes can be read simultaneously, using spread spectrum multiple access techniques. In this thesis, 63-chip and 255-chip Kasami sequences, as well as 127-chip Gold sequences, will be analyzed for their use in various aperiodic direct sequence spread spectrum/multiple access system configurations (systems that have up to three nodes and use up to four different aperiodic sequences per node to represent different symbols). For each different configuration, near-"ideal" code configurations/rotations will be determined for use in the system.
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Guadiana, Juan M., and Fil Macias. "ENCRYPTED BIT ERROR RATE TESTING." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/607507.
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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, CaliforniaEnd-to-End testing is a tool for verifying that Range Telemetry (TM) System Equipment will deliver satisfactory performance throughout a planned flight test. A thorough test verifies system thresholds while gauging projected mission loading all in the presence of expected interference. At the White Sands Missile Range (WSMR) in New Mexico, system tests are routinely conducted by Range telemetry Engineers and technicians in the interest of ensuring highly reliable telemetry acquisition. Even so, flight or integration tests are occasionally halted, unable to complete these telemetry checks. The Navy Standard Missile Program Office and the White Sands Missile Range, have proactively conducted investigations to identify and eliminate problems. A background discussion is provided on the serious problems with the launcher acquisition, which were resolved along the way laying the ground work for effective system testing. Since there were no provisions to test with the decryption equipment an assumption must be made. Encryption is operationally transparent and reliable. Encryption has wide application, and for that reason the above assumption must be made with confidence. A comprehensive mission day encrypted systems test is proposed. Those involved with encrypted telemetry systems, and those experiencing seemingly unexplainable data degradations and other problems with or without encryption should review this information.
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Hugo, Jan Marais. "Switch a BRT terminal as change generator at Pretoria Main Station." Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/30291.
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The study responds to the increasing effect that climate change has on earth and society. In a global context of rapid urbanization and population growth the project aims to establish the role that architecture can play in the mitigation of climate change. It addresses the embodied energy and carbon footprint of architecture in an urban context. The architectural building type that will be investigated is a transport interchange, specifically the BRT terminal at Pretoria Main Station and associated prototypical BRT stations. An architectural response that promotes public transport use will be investigated. The proposed transport interchange will act as a seam to linking Salvokop with the city, while linking the whole of Tshwane. The architectural intervention will use strategies to respond to predicted climate changes for Tshwane, and adopt strategies to mitigate it. Architectural technologies will be investigated to ensure that the structure has a low carbon footprint and low embodied energy. Through energy conscious design strategies the energy use of the structure will be kept to a minimum. The design will also address the social and historical context of the Pretoria Main Station, to ensure a coherent transport interchange that integrates all modes of transport. The design will contribute to the historical character of the site with an ecosystemic layered approach, adding new functions and layers to the existing, to ensure its adaptability and sustainability. This study forms the part of a departmental research study through the department of Architecture at Pretoria University - “Environmental potential” and the United Nations Development Programme [UNDP] and Global Environment Facility [GEF]. It aims to comply with the prerequisites for an M[Prof]Arch degree while achieving the goals and objectives set by the research study.Dissertation (MArch(Prof))--University of Pretoria, 2010.
Architecture
unrestricted
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Johannesson, Kristoffer, and Rasmus Petersson. "BDT-SYSTEM FÖR SPOLNING AV WC : En studie om utformning av system som återanvänder BDT-vatten." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-41102.
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Syfte: Varje dag spolar vi ner ungefär 30 liter vatten i toaletten. Att det är rent dricksvatten som används i detta syfte är inte en hållbar lösning med hänsyn till den globala uppvärmningen och problemen den för med sig. I Sverige har vi redan sett tecken på vattenbrist och utvecklingen ser inte ut att gå mot det positiva. En bättre hushållning med vårt vatten är ett förslag på en mer hållbar utveckling gällande vattenförbrukningen och ett alternativ till ett sådant förslag beskrivs i denna rapport. Att lokalt kunna återanvända BDT-vatten till att spola toaletterna kan spara närmare 30 % av den totala vattenförbrukningen. BDT-vatten innehåller flertalet skadeämnen och för att denna återanvändning ska kunna ske måste det säkerställas att det inte medför några hälsorisker. Målet med arbetet är att skapa ett system med god teoretisk tillförlitlighet samt undersöka den ekonomiska hållbarheten av ett sådant system vid införandet i nybyggnation av ett flerbostadshus. Metod: För att uppnå detta mål har en omfattande litteraturstudie av BDT-vattnets karaktär samt befintliga system genomförts. Intervjuer med personer inom VVS-branschen samt personer med kunskap inom olika reningsmetoder har genomförts för att få en bredare kunskap i ämnet. Resultat: Rapporten beskriver utformningen av ett fysiskt system anpassat till nybyggnation av flerbostadshus med 30 lägenheter. Resultatet visar att det finns möjlighet till besparing av dricksvatten samt möjlighet till ekonomisk vinning vid återanvändning av BDT-vatten.Systemet har god teoretisk tillförlitlighet men författarna föreslår vidare forskning i form av empirisk prövning av systemets funktionsduglighet. Konsekvenser: Införandet av ett system som återvinner BDT-vatten innebär flera förändringar i det befintliga arbetssättet. Förändringar tar ofta lång tid att införa i den svenska byggbranschen. Trots detta hade implementeringen inneburit flera fördelar i införandet av ett sådant system, där en reducering i dagens dricksvattenanvändning är en av de viktigaste. Med dagens teknik kan man på ett pålitligt sätt rena BDT-vattnet till den grad då det inte är hälsoskadligt. Möjligheten till ekonomisk vinning bör motivera implementeringen av ett sådant system vid nybyggnation av större flerbostadshus. Begränsningar: Vi har endast sett till möjligheten att införa ett system i Sverige med lagar och regler som gäller här. Den ekonomiska aspekten baseras på nybyggnation av ett flerbostadshus.Endast BDT-vatten kommer att analyseras. Nyckelord: Ekonomisk analys, filter, hälsoskadliga ämnen i BDT-vatten, membranseparationrening av BDT-vatten.
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Bergman, Svante. "Bit loading and precoding for MIMO communication systems." Doctoral thesis, Stockholm : Skolan för elektro- och systemteknik, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10622.
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Faulkner, M. "Topological and emergent phenomena in lattice BKT systems." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1466258/.
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This thesis addresses the emergent electrostatics of two-dimensional, toroidal magnetic models that possess XY symmetry, providing a platform for novel investigations into the Berezinskii-Kosterlitz-Thouless (BKT) phase transition. The BKT transition drives the thermal dissociation of bound pairs of topological defects in many two-dimensional systems, including the two-dimensional XY model of magnetism. The XY model is closely analogous to the two-dimensional Coulomb gas, but can be simulated without computing the long-range interactions of the Coulombic system. This thesis elucidates this paradox by showing that Villain's approximation to the XY model is strictly equivalent to the Maggs-Rossetto (MR) electrostatic model when applied to the two-dimensional Coulomb gas. The mapping is used to probe the BKT transition through the application of the MR algorithm to the two-dimensional Coulomb gas. By simulating the Coulombic system, fluctuations in the winding of charges around the torus are shown to turn on at the BKT transition temperature. These topological-sector fluctuations in the electric field therefore signal the high-temperature phase of the transition. It is then shown that the effective critical exponent of Bramwell-Holdsworth (BH) theory can be measured in superfluid ⁴He films, which correspond to effective Coulomb gases in the limit of large but finite system size. With the Coulombic system taken as the base BKT system, it is inferred that BH theory is a general property of BKT systems.
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LeBlanc, Wilfrid P. (Wilfrid Paul) Carleton University Dissertation Engineering Electrical. "Speech coding at low to medium bit rates." Ottawa, 1992.
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Wilkinson, Timothy James. "Implementing fault tolerance in a 64-bit distributed operating system." Thesis, City University London, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356977.
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Zhu, Qiwei. "BERT and FFT measurement systems for high-speed communications and magnetometry." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-149321.
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This master thesis presents the development and implementation of two digital systems based on Field-programmable Gate Array (FPGA): a Bit Error Rate Testing (BERT) system for an Optical Communication (OCOM) application, and a Digital Signal Processing (DSP) system for a Spin-Dependent Tunneling Magnetometer (SDTM). Both applications are intended for space and currently under development at the Ångström Space Technology Center (ÅSTC). The DSP system samples analog signals and applies a Fast Fourier Transform (FFT) for to provide frequency spectrum analysis. The report covers detailed system designs, state machine designs, and accounts for system verifications and measurements. As the live OCOM system and SDTM were unavailable by the time of testing, a series of emulated testing cases was set up to evaluate the digital systems developed. The BERT system was evaluated by checking the bit error rate of a stranded wire connection and a coaxial cable. Analog square and sine wave signals were used to evaluate the performance and accuracy of the FFT in the DSP system. Both systems were functionally verified using the Altera SignalTap II Logic Analyzer. Analysis of the measurement results for the testing cases indicates that the BERT works well at clock frequencies of 50 and 125 MHz, and that the coaxial cable is more suitable for data transmission as it gives a lower bit error rate than the stranded wire. The DSP system was verified to work well at a clock frequency of 62.5 MHz, and is able to sample any waveform at a sampling frequency of 62.5 MHz and continuously gets, at maximum, 14-bit wide digital signals. The sample point lengths for FFT are 64, 512 and 1024, and the data transfer rate between the FPGA and the computer reaches 115200 baud. In conclusion, the developed BERT and DSP system can be used to support the OCOM and the SDTM hardware, respectively.
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Kritzinger, Carl. "Low bit rate speech coding." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2078.
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Thesis (MScIng (Electrical and Electronic Engineering))--University of Stellenbosch, 2006.Despite enormous advances in digital communication, the voice is still the primary tool with which people exchange ideas. However, uncompressed digital speech tends to require prohibitively high data rates (upward of 64kbps), making it impractical for many applications. Speech coding is the process of reducing the data rate of digital voice to manageable levels. Parametric speech coders or vocoders utilise a-priori information about the mechanism by which speech is produced in order to achieve extremely efficient compression of speech signals (as low as 1 kbps). The greater part of this thesis comprises an investigation into parametric speech coding. This consisted of a review of the mathematical and heuristic tools used in parametric speech coding, as well as the implementation of an accepted standard algorithm for parametric voice coding. In order to examine avenues of improvement for the existing vocoders, we examined some of the mathematical structure underlying parametric speech coding. Following on from this, we developed a novel approach to parametric speech coding which obtained promising results under both objective and subjective evaluation. An additional contribution by this thesis was the comparative subjective evaluation of the effect of parametric speech coding on English and Xhosa speech. We investigated the performance of two different encoding algorithms on the two languages.
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Thoma, Berthold. "Bit error rate simulation enhancement and outage prediction in mobile communication systems." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09052009-040547/.
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Ong, Leh Kui. "Source reliant error control for low bit rate speech communications." Thesis, University of Surrey, 1994. http://epubs.surrey.ac.uk/843456/.
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Contemporary and future speech telecommunication systems now utilise low bit rate (LBR) speech coding techniques in efforts to eliminate bandwidth expansion as a disadvantage of digital coding and transmission. These speech coders employ model-based approaches in compressing human speech into a number of parameters, using a well-known process known as linear predictive coding (LPC). However, a major side-effect observed in these coders is that errors in the model parameters have noticeable and undesirable consequences on the synthesised speech quality, and unless they are protected from such corruptions, the level of service quality will deteriorate rapidly. Traditionally, forward error correction (FEC) coding is used to remove these errors, but these require substantial redundancy. Therefore, a different perspective of the error control problems and solutions is necessary. In this thesis, emphasis is constantly placed on exploiting the constraints and residual redundancies present in the model parameters. It is also shown that with such source criteria in the LBR speech coders, varying degrees of error protection from channel corruptions are feasible. From these observations, error control requirements and methodologies, using both block- and parameter-orientated aspects, are analysed, devised and implemented. It is evident, that under the unusual circumstances which LBR speech coders have to operate in, the importance and significance of source reliant error control will continue to attract research and commercial interests. The work detailed in this thesis is focused on two LPC-based speech coders. One of the ideas developed for these two coders is an advanced zero redundancy scheme for the LPC parameters which is designed to operate at high channel error rates. Another concept proposed here is the use of source criteria to enhance the decoding capabilities of FEC codes to exceed that of maximum likelihood decoding performance. Lastly, for practical operation of LBR speech coders, lost frame recovery strategies are viewed to be an indispensable part of error control. This topic is scrutinised in this thesis by investigating the behaviour of a specific speech coder under irrecoverable error conditions. In all of the ideas pursued above, the effectiveness of the algorithms formulated here are quantified using both objective and subjective tests. Consequently, the capabilities of the techniques devised in this thesis can be demonstrated, examples of which are: (1) higher speech quality produced under noisy channels, using an improved zero-redundancy algorithm for the LPC filter coefficients; (2) as much as 50% improvement in the residual BER and decoding failures of FEC schemes, through the utilisation of source criteria in LBR speech coders; and (3) acceptable speech quality produced under high frame loss rates (14%), after formulating effective strategies for recovery of speech coder parameters. It is hoped that the material described here provide concepts which can help achieve the ideals of maximum efficiency and quality in LBR speech telecommunications.
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Gustavsson, Martin, and Viktor Frimodig. "Virtual Prototyping and Physical Validation of an Inverted Pendulum : "Sea-Calf Bot"." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-27946.
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The work is motivated by the goal of linking reality and model, and to see if there is an opportunity to develop an inexpensive educational tool for training in cyber-physical systems. This project has investigated the possibilities to build a cheap inverted pendulum with controller and connect this with the modeling language Acumen. Acumen models is used for comparison with the actual prototype. To solve these problems has a 3D printer been used to create hardware, Arduino UNO for control and Raspberry Pi for enable communication with Acumen over WLAN. The result was a cheap inverted pendulum, which can be built for a cost around 750 SEK. Graphs created in Acumen and from data collected from sensors can be analyzed. With a model of the inverted pendulum system, the results show that Acumen can be used in the development of cyber-physical systems. There are differences between model and reality but also similarities.Arbetet motiveras av målet att knyta samman verklighet och modell, samt att se om det finns möjlighet att utveckla ett billigt utbildningsverktyg för utbildning i cyberfysiska system. Detta projekt har undersökt möjligheter att bygga en billig inverterad pendel med regulator samt koppla samman denna med modelleringsspråket Acumen. I Acumen skapa en modell av systemet och jämföra den med en fysisk prototyp. För att lösa dessa problem har en 3D skrivare använts för att skapa hårdvara. Arduino UNO för styrning och Raspberry Pi för att möjligöra kommunikation med Acumen över WLAN. Resultatet blev en billig inverterad pendel, som kan byggas för en kostnad runt 750 kr. Grafer från Acumen, och från data samlad från sensorer kan analyseras. Med en modell av en inverterad pendel visar resultaten att Acumen kan användas i utveckling av cyberfysiska system. Skillnader finns mellan modell och verklighet men även likheter.
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Vasquez, Bustamante Jose Luis, Ochoa Chavez Raphael Marcelo, Manuel Silvera, and Fernando Castro. "Optimization of passengers boarding in the BRT system based on the security protocols established by the Covid-19 pandemic." Institute of Electrical and Electronics Engineers Inc, 2020. http://hdl.handle.net/10757/656570.
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El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.According to the National Institute of Statistics and Informatics (INEI), the city of Lima has more than 9,485,405 inhabitants. This causes problems of pedestrian crowding in public places. The Bus Rapid Transit (BRT) system called Metropolitano transports 650,000 passengers a day, of which 81,800 of them use the boarding platform of the Naranjal station located in one of the most populated districts of Lima. In this station are concentrated 12.6% users of the entire transportation system. This research proposes a pedestrian microsimulation model with the objective of optimizing the pedestrian area of one of the most demanded platforms in Lima, considering the security protocols established by the Covid-19 Pandemic. To obtain results, the parameters of pedestrian density, bus frequency and queuing time were considered. The effectiveness of the proposed design is validated using a model made with the software Vissim. The results showed that the maximum number of pedestrians that can occupy the Naranjal station following the Covid-19 security protocols are 4166 persons, considering a 180 second bus frequency on lines with the highest demand and a maximum queuing time of 764.51 seconds.
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Chen, Wei 1976. "Perceptual postfiltering for low bit rate speech coders." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112563.
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Adaptive postfiltering has become a common part of speech coding standards based on the Linear Prediction Analysis-by-Synthesis algorithm to decrease audible coding noise. However, a conventional adaptive postfilter is based on empirical assumptions of masking phenomena, which sometimes makes it hard to balance between noise reduction and speech distortion.This thesis introduces a novel perceptual postfiltering system for low bit rate speech coders. The proposed postfilter works at the decoder, as is the case for the conventional adaptive postfilter. Specific human auditory properties are considered in the postfilter design to improve speech quality. A Gaussian Mixture Model based Minimum Mean Squared Error estimation of the perceptual postfilter is performed with the received information at the decoder. Perceptual postfiltering is then applied to the reconstructed speech to improve speech quality. Test results show that the proposed system gives better perceptual speech quality over conventional adaptive postfiltering.
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Gutmann, Henryk. "Description and control of decoherence in quantum bit systems." Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-40861.
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He, Xiaohui. "Bit-interleaved coded modulation for hybrid rf/fso systems." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2868.
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In this thesis, we propose a novel architecture for hybrid radio frequency
(RF)/free–space optics (FSO) wireless systems. Hybrid RF/FSO systems
are attractive since the RF and FSO sub–systems are affected differently by
weather and fading phenomena. We give a thorough introduction to the RF
and FSO technology, respectively. The state of the art of hybrid RF/FSO systems
is reviewed. We show that a hybrid system robust to different weather
conditions is obtained by joint bit–interleaved coded modulation (BICM) of the
bit streams transmitted over the RF and FSO sub–channels. An asymptotic
performance analysis reveals that a properly designed convolutional code can
exploit the diversity offered by the independent sub–channels. Furthermore,
we develop code design and power assignment criteria and provide an efficient
code search procedure. The cut–off rate of the proposed hybrid system is also
derived and compared to that of hybrid systems with perfect channel state
information at the transmitter. Simulation results show that hybrid RF/FSO
systems with BICM outperform previously proposed hybrid systems employing
a simple repetition code and selection diversity.
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Edirisinghe, Sumuda G. "Dispersion compensation techniques in high bit rate transmission systems." Thesis, University of Essex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343578.
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Eustace, Natalie Margaret. "Biological Realistic Education Technology (BRET)." Thesis, University of Canterbury. HIT Lab NZ, 2014. http://hdl.handle.net/10092/9242.
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The aim of this project was to develop and evaluate an interactive Augmented Reality interface for teaching children aged 8 to 15 about biological systems present in the human body. The interface was de- signed as one component of a “human body scanner” exhibit, which is to be featured at the ScienceAlive! Science Centre. In the exhibit, the interface allows visualization and interaction with the body systems while being moved across a human male mannequin named BRET.
Prior research has shown that Augmented Reality, Visualization applications, and games are viable methods to teach biology to university aged users, and Augmented Reality and interactive systems have been used with children and learning biology as well.
BRET went through three iteration phases, in the first phase, prototypes were evaluated by ScienceAlive! and designs and interactions were implemented, while the use of Augmented Reality through a transparent display was rejected. Iteration two included integration of the non-transparent touch display screen and observational evaluation of six children from 9 to 15 years old. This evaluation resulted in design and interaction changes. Iteration three was the last iteration where final interface and interaction modifications were made and re- search was conducted with 48 children from the ages 8 to 15. This was to determine whether learning, fun, and retention rates were higher for children who interacted with BRET versus those who watched video clips, or read text. Each child used one learning method to learn the three different body systems: skeletal, circulatory, and digestion. The results of the final evaluation showed that overall there was no significant difference in the children’s rating of fun or the amount of information they retained between the different learning methods. There was a positive significant difference between some of the expected fun scores and the actual fun scores. It was also found that learning with text was higher than the interactive condition but there was no differences between learning with video and interaction, or with text and video.
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Saito, Masato, Takaya Yamazato, Masaaki Katayama, and Akira Ogawa. "Throughput Performance of CDMA Slotted ALOHA Systems Based on Average Packet Success Probability Considering Bit-to-Bit Dependence." IEICE, 2001. http://hdl.handle.net/2237/7221.
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Huang, Yuheng. "Bit-interleaved coded modulation with iterative decoding for wireless communications /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/5903.
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Li, Guanying. "The potential of a bus rapid transit / buses with high level of service system in metro Atlanta: A suitability and feasibility study." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51809.
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The Atlanta Metropolitan Area has been long suffering from traffic congestion, and the ongoing population growth will exacerbate the situation. On the other hand, over half of current transit riders are people from lower-income households and there is a growing senior population more than likely to rely on transit over the next two decades. One way to mitigate congestion and support transit dependent riders at the same time is to promote transit service. Enhanced bus service systems including Bus Rapid Transit (BRT) and Buses with High Level of Service (BHLS) have been gaining popularity across the world, especially in South and East Asia, Latin America, and Europe. While there are also many BRT systems in the United States, only a few of them actually meet the world standards for providing a dedicated bus lane. Even so, case studies show that there are viable alternatives for implementing successful enhanced transit service:
• Choosing population-activity concentrated corridor;
• Adopting variations of exclusive right-of-way;
• Providing long span and high frequency service; and
• Using off-board fare collection, among others. Just like the benchmark cases, Metro Atlanta also has corridors with high population density, activity centers, relatively simple straight alignment, but that are currently underserved by bus service. If all the transit agencies, the Georgia Department of Transportation, and City of Atlanta, could work closely with the public to establish an enhanced bus transit system, traffic conditions in Metro Atlanta would be greatly improved.
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McCree, Alan V. "A new LPC vocoder model for low bit rate speech coding." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/15053.
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Kim, Hyun Soo Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Speech analysis techniques useful for low or variable bit rate coding." Awarded by:University of New South Wales. School of Electrical Engineering and Telecommunications, 2005. http://handle.unsw.edu.au/1959.4/22050.
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We investigate, improve and develop speech analysis techniques which can be used to enhance various speech processing systems, especially low bit rate or variable bit rate coding of speech. The coding technique based on the sinusoidal representation of speech is investigated and implemented. Based on this study of the sinusoidal model of speech, improved analysis techniques to determine voicing, pitch and spectral estimation are developed, as well as noise reduction technique. We investigate the properties and limitations of the spectral envelope estimation vocoder (SEEVOC). We generalize, optimize and improve the SEEVOC and also compare it with LP in the presence of noise. The properties and applications of morphological filters for speech analysis are investigated. We introduce and investigate a novel nonlinear spectral envelope estimation method based on morphological operations, which is found to be very robust against noise. This method is also compared with the SEEVOC method. A simple method for the optimum selection of the structuring set size without using prior pitch information is proposed for many purposes. The morphological approach is then used for a new pitch estimation method and for the general sinusoidal analysis of speech or audio. Many of the new methods are based on a novel systematic analysis of the peak features of signals, including the study of higher order peaks. We propose a novel peak feature algorithm, which measure the peak characteristics of speech signal in time domain, to be used for end point detection and segmentation of speech. This nonparametric algorithm is flexible, efficient and very robust in noise. Several simple voicing measures are proposed and used in a new speech classifier. The harmonic-plus-noise decomposition technique is improved and extended to give an alternative to the methods used in the sinusoidal analysis method. Its applications to pitch estimation, speech classification and noise reduction are investigated.
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Oh, Min-seok. "Low complexity bit-level soft-decision decoding for Reed-Solomon codes." Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/842687/.
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Reed-Solomon codes (RS codes) are an important method for achieving error-correction in communication and storage systems. However, it has proved difficult to find a soft-decision decoding method which has low complexity. Moreover, in some previous soft-decision decoding approaches, bit-level soft-decision information could not be employed fully. Even though RS codes have powerful error correction capability, this is a critical shortcoming. This thesis presents bit-level soft-decision decoding schemes for RS codes. The aim is to design a low complexity sequential decoding method based on bit-level soft- decision information approaching maximum likelihood performance. Firstly a trellis decoding scheme which gives easy implementation is introduced, since the soft-decision information can be used directly. In order to allow bit-level soft-decision, a binary equivalent code is introduced and Wolf's method is used to construct the binary-trellis from a systematic parity check matrix. Secondly, the Fano sequential decoding method is chosen, which is sub-optimal and adaptable to channel conditions. This method does not need a large amount of storage to perform an efficient trellis search. The Fano algorithm is then modified to improve the error correcting performance. Finally, further methods of complexity reduction are presented without loss of decoding performance, based on reliability-first search decoding using permutation groups for RS codes. Compared with the decoder without permutation, those schemes give a large complexity reduction and performance improvement approaching near maximum likelihood performance. In this thesis, three types of permutation, cyclic, squaring and hybrid permutation, are presented and the decoding methods using them are implemented.
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Hu, Tianrui. "Detecting Bots using Stream-based System with Data Synthesis." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/98595.
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Machine learning has shown great success in building security applications including bot detection. However, many machine learning models are difficult to deploy since model training requires the continuous supply of representative labeled data, which are expensive and time-consuming to obtain in practice. In this thesis, we build a bot detection system with a data synthesis method to explore detecting bots with limited data to address this problem. We collected the network traffic from 3 online services in three different months within a year (23 million network requests). We develop a novel stream-based feature encoding scheme to support our model to perform real-time bot detection on anonymized network data. We propose a data synthesis method to synthesize unseen (or future) bot behavior distributions to enable our system to detect bots with extremely limited labeled data. The synthesis method is distribution-aware, using two different generators in a Generative Adversarial Network to synthesize data for the clustered regions and the outlier regions in the feature space. We evaluate this idea and show our method can train a model that outperforms existing methods with only 1% of the labeled data. We show that data synthesis also improves the model's sustainability over time and speeds up the retraining. Finally, we compare data synthesis and adversarial retraining and show they can work complementary with each other to improve the model generalizability.Master of Science
An internet bot is a computer-controlled software performing simple and automated tasks over the internet. Although some bots are legitimate, many bots are operated to perform malicious behaviors causing severe security and privacy issues. To address this problem, machine learning (ML) models that have shown great success in building security applications are widely used in detecting bots since they can identify hidden patterns learning from data. However, many ML-based approaches are difficult to deploy since model training requires labeled data, which are expensive and time-consuming to obtain in practice, especially for security tasks. Meanwhile, the dynamic-changing nature of malicious bots means bot detection models need the continuous supply of representative labeled data to keep the models up-to-date, which makes bot detection more challenging. In this thesis, we build an ML-based bot detection system to detect advanced malicious bots in real-time by processing network traffic data. We explore using a data synthesis method to detect bots with limited training data to address the limited and unrepresentative labeled data problem. Our proposed data synthesis method synthesizes unseen (or future) bot behavior distributions to enable our system to detect bots with extremely limited labeled data. We evaluate our approach using real-world datasets we collected and show that our model outperforms existing methods using only 1% of the labeled data. We show that data synthesis also improves the model's sustainability over time and helps to keep it up-to-date easier. Finally, we show that our method can work complementary with adversarial retraining to improve the model generalizability.
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Ng, Ka Wai. "Generalized bit and power allocation for single and multi-user OFDM MIMO system in frequency selective fading channel /." View abstract or full-text, 2003. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202003%20NG.
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Levay, Anders, and Olof Roos. "Energieffektivisering av flerbostadshus : Energibesparande åtgärder för Brf Lillåudden 3." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-40003.
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The European Union’s goal for year 2020 aims to reduce the greenhouse gases by 20 % compared to the levels of 1990. This goal can be reached by increasing energy efficiency and renewable energy sources by 20 %. In Sweden housing stands for 40 % of the total energy usage and in apartment buildings district heating is the most used way for heating and hot water. In this degree project two apartment buildings, connected by a garage, have been studied to see which solutions would yield a saving in both money and the environment. The building is heated using district heating and is ventilated through mechanical exhaust ventilation. Analyzing the current energy consumption and ventilation rates, two heat pump manufacturers was contacted to see what their systems could save in terms of energy. By recovering heat from the exhaust air with a heat pump the buildings can save both money and have a reduced impact on the environment. Having a demand-controlled ventilation in the garage would not give a large enough saving in energy to be worth the investment. The already scheduled fans have decreased their energy usage by half. However by having a demand-controlled ventilation in the garage it could reduce the harmful heavy metals that get released when cars drive in and out. By simply lowering the temperature in the garage from 15 °C to 10 °C could save about 12 500 sek/year in heating costs. The conclusion to this study is that using a heat pump to recover energy from exhaust air is an investment that will generate financial savings for the cooperative apartment and have a reduced negative impact on the environment.
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Olofsson, Anthon. "Att skapa en plattformsoberoende applikation med bra användarupplevelse." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-74828.
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Li, Yingjie. "Bit error rate simulation of a CDMA system for personal communications." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-07282008-135717/.
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Kim, Hyun Soo. "Bat Intelligent Hunting Optimization with Application to Multiprocessor Scheduling." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1274471808.
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Shi, Yuanjing. "Investigation of island geometry variations in bit patterned media storage systems." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/investigation-of-island-geometry-variations-in-bit-patterned-media-storage-systems(b16092b6-7260-4dc5-aa30-7dabb2c7a46f).html.
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Bit-Patterned Media (BPM) has been recognised as one of the candidate technologies to achieve an areal density beyond 1Tb/in2 by fabricating single-domain islands out of continuous magnetic media. Though much attention has been focused on the fabrication of BPM, existing lithography techniques demonstrate difficulties in producing uniform islands over large areas cost effectively; the resulting fabricated islands often vary in position and size. The primary purpose of the research documented in this thesis is to investigate the issue of island geometry variations on the data recovery process from a perpendicular patterned media with head and media configurations optimised to achieve an areal density of 1Tb/in2. In order to achieve the research aim, a read channel model has been implemented as a platform to evaluate the read channel performance numerically. It can be also altered to investigate new read channel designs. The simulated results demonstrate that island geometry variations have a detrimental effect on read channel performance. It has shown that a BPM system can be tolerant to island position variations, but more effort needs to be paid to the effect that island size variations have on the read channel performance. A new read channel design revolving around the design of a modified trellis has been proposed for use in the Viterbi detector in order to combat the effect of island geometry variations. The modified trellis for island position variations results in extra states and branches compared to the standard trellis, while the modified trellis for island size variations results in only extra branches. The novel read channel designs demonstrate an improved read channel performance in the presence of island geometry variations even with increasing amounts of island position and size variations. There are two ways to obtain the read channel performance in terms of the bit-error-rate (BER): a) by running a numerical Monte-Carlo simulation to count the number of bits in error at the output of the read channel model and b) using an analytical approach to calculate the BER by approximating the noise into a known distribution. It is shown that both ways demonstrate very similar results, which indicates as long as the distribution of the noise present in read channel model is predictable, the analytical approach can evaluate the BER performance more efficiently, especially when the BER is low. However, the Monte-Carlo simulation is still useful for understanding of the correlation of the errors. Novel trellis proposed in this work will contribute to the commercial development of BPM in two ways: a) to improve the data recovery process in BPM systems, b) to allow a tolerance of 10% size variations for the existing fabrication techniques.
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Yeldener, Suat. "Sinusoidal model based low bit rate speech coding for communication systems." Thesis, University of Surrey, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359842.
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Seong, Seok-Won. "Dictionary-based code compression techniques using bit-masks for embedded systems." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0013980.
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Law, Gene, and Don Whiteman. "IFM EFFECTS ON PCM/FM TELEMETRY SYSTEMS." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/607378.
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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, CaliforniaIncidental Frequency Modulation (IFM) products in telemetry transmitters can be a significant cause of bit errors in received Pulse Code Modulation/Frequency Modulation (PCM/FM) telemetry data. Range Commanders Council (RCC) and other documents give little or no guidance as to acceptable levels of IFM for telemetry applications. The expected higher vibration levels of future high velocity missile systems means that IFM levels are likely to be higher than previously encountered. This paper presents measured data on Bit Error Rate (BER) versus IFM levels at given Signal to Noise Ratios (SNR’s) for PCM/FM telemetry systems. The information presented can be utilized with BER versus SNR plots in the Telemetry Applications Handbook, RCC Document 119, to determine the additional link margin required to minimize IFM effects on telemetry data quality.
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Pozo, Fortunić Juan Edmundo. "Design and implementation of a bristle bot swarm system." Master's thesis, Pontificia Universidad Católica del Perú, 2016. http://tesis.pucp.edu.pe/repositorio/handle/123456789/7686.
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Swarm robotics focuses on the study and development of robot systems containing a large number of agents that interact with each other in a collective behaviour in order to achieve tasks or overcome obstacles. Bristlebots are vibration-driven mobile robots. They are characterized by small size, high speed, simple design and low costs for production and application – qualities which are advantageous for agents of swarm robotic systems. However, most studies have been developed over systems with no control or systems with two or more actuators.
The aim of this master thesis is the development of a bristle based robot agent for a swarm robotics microsystem with units for locomotion, sensing, data processing, control, communication and energy storage. New approaches in modelling and development of swarm agents are given, and a robot prototype is presented. The robot is driven by a single DC motor and uses a bristle system to create locomotion. It should be noted, that within the system design, considerations for the size, weight and minimalist architecture are taken.
Experiments are presented and the system’s capabilities for displacement, velocity and trajectory generation are analysed. While the parallel velocity maintains a positive magnitude in both motor rotation directions, the rotation speed and transversal velocity of the robot have opposite directions, creating curved trajectories with opposite orientations. In Frequencies up to 210 Hz, the rotation direction of the robot is maintained while the magnitude slightly varies. However, for higher frequencies, the rotation direction of the robot is reversed, maintaining a similar magnitude. The transversal speeds at this frequency range, maintain their direction but are clearly reduced compared to lower frequencies.Tesis
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Ourak, Pour Cyrus. "Energieffektivisering av Brf. Mörbylund : Förbättringsåtgärder i ett FTX- system." Thesis, Högskolan Dalarna, Energiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-34235.
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Utifrån ett effektiviseringsperspektiv beror en byggnads inomhusklimat på flera enskilda system som tillsammans tillför och balanserar erforderligt energibehov till byggnaden, och samtidigt har de växelverkan med varandra. Systemen är uppvärmningssystem, kylsystem, ventilationssystem, samt styr-och reglersystem som spelar roll av hjärna för de andra. I detta examensarbete är ventilationssystemet i fokus. Numera finns i Sverige olika typer av ventilationssystem. Ett av de vanligaste ventilationssystemen är till-och frånluftsventilation med värmeåtervinning, typ FTX som har två fläktar. Fläkten är en huvudkomponent i ett mekaniskt ventilationssystem och dess skovlar är avgörande för skapande tryck och kan utformas på olika sätt. I Brf. Mörbylund 11–15 i Danderyd kommun tänker föreningen vidta några effektiviseringsåtgärder som ska sänka elkostnaden för 3 stycken luftbehandlingsaggregat. I de allra flesta fall beror hög elförbrukning på gamla fläktar i FTX-system som har höga specifik fläkteleffekt, eller SFP-tal. För att sänka elenergin på aggregaten krävs det att undersöka olika parametrar som gäller aggregaten. Därför behövs mätvärden av parametrar såsom lufttryck, flöde, fläktsverkningsgrad, elförbrukning till fläktar och shuntgrupper som kopplas till luftvärme i aggregaten. Därefter jämförs mätningar över befintliga samt nyinstallerade fläktar, och shuntgrupper. Vid undersökning av de uppmätta parametrarna över befintliga respektive nya komponenter leder det till ett ekonomiskt resultat som speglar konsekvensen av de vidtagna åtgärderna i luftbehandlingsaggregaten. Teorin i denna rapport beskriver de viktiga komponenterna och delarna i ett ventilationssystem, och baseras bland annat på “Projektering av VVS-installationer” av C. Warfvinge & M. Dahlblom. I teoridelen visas flera statistiska fakta kring användning av olika ventilationssystem i Sverige, samt mest ligger fokus på den typen av ventilationssystem som finns i Brf. Mörbylund 11–15, FTXsystem. Under titeln, “Mätmetoder” kommer en del förklaringar av tryckfallberäkning, flöde och fläktdiagram. I teoridelen diskuteras också regler och förutsättningar som presenteras av BBR i detta område som kan hittas i avsnittet, “Myndighetskrav”. Vidare beskrivs det studerade objektet och dess komponenter. I den ekonomiska delen visas två olika kalkylmetoder. Den ena som används av HSB-företag och den andra som väljs av författaren till rapporten för att beräkna möjlig vinst. De är pay-back, och annuitetsmetod. Pay-back-metoden har till nackdel att inte ta hänsyn till låneränta och ekonomisk livslängd vilket däremot är avgörande för annuitetsmetod. Resultatet av annuitetsmetoden visar en negativ summa för kalkylering fastän själva åtgärden är energieffektiv. Det negativa resultatet kan tolkas på olika sätt. Exempelvis kan det bero på olika arbete mellanhänder (mäklaren) som finns mellan föreningen och den första aktören som tillverkar och säljer de önskande komponenterna. I rapporten presenteras och undersökas olika möjliga förklarningar.
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Morales, Jhonny Rodrigo Rojas. "Applicability conditions for the implementation of BRT systems. Case study of Coimbra." Dissertação, 2016. https://repositorio-aberto.up.pt/handle/10216/84362.
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Morales, Jhonny Rodrigo Rojas. "Applicability conditions for the implementation of BRT systems. Case study of Coimbra." Master's thesis, 2016. https://repositorio-aberto.up.pt/handle/10216/84362.
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