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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.
211

Energy-efficient memory hierarchy for motion and disparity estimation in multiview video coding

Sampaio, Felipe Martin January 2013 (has links)
Esta dissertação de mestrado propõe uma hierarquia de memória para a Estimação de Movimento e de Disparidade (ME/DE) centrada nas referências da codificação, estratégia chamada de Reference-Centered Data Reuse (RCDR), com foco em redução de energia em codificadores de vídeo multivistas (MVC - Multiview Video Coding). Nos codificadores MVC, a ME/DE é responsável por praticamente 98% do consumo total de energia. Além disso, até 90% desta energia está relacionada com a memória do codificador: (a) acessos à memória externa para a busca das referências da ME/DE (45%) e (b) memória interna (cache) para manter armazenadas as amostras da área de busca e enviá-las para serem processadas pela ME/DE (45%). O principal objetivo deste trabalho é minimizar de maneira conjunta a energia consumida pelo módulo de ME/DE com relação às memórias externa e interna necessárias para a codificação MVC. A hierarquia de memória é composta por uma memória interna (a qual armazena a área de busca inteira), um controle dinâmico para a estratégia de power-gating da memória interna e um compressor de resultados parciais. Um controle de buscas foi proposto para explorar o comportamento da busca com o objetivo de atingir ainda mais reduções de energia. Além disso, este trabalho também agrega à hierarquia de memória um compressor de quadros de referência de baixa complexidade. A estratégia RCDR provê reduções de até 68% no consumo de energia quando comparada com estratégias estadoda- arte que são centradas no bloco atual da codificação. O compressor de resultados parciais é capaz de reduzir em 52% a comunicação com memória externa necessária para o armazenamento desses elementos. Quando comparada a técnicas de reuso de dados que não acessam toda área de busca, a estratégia RCDR também atinge os melhores resultados em consumo de energia, visto que acessos regulares a memórias externas DDR são energeticamente mais eficientes. O compressor de quadros de referência reduz ainda mais o número de acessos a memória externa (2,6 vezes menos acessos), aliando isso a perdas insignificantes na eficiência da codificação MVC. A memória interna requerida pela estratégia RCDR é até 74% menor do que estratégias centradas no bloco atual, como Level C. Além disso, o controle dinâmico para a técnica de power-gating provê reduções de até 82% na energia estática, o que é o melhor resultado entre os trabalho relacionados. A energia dinâmica é tratada pela técnica de união dos blocos candidatos, atingindo ganhos de mais de 65%. Considerando as reduções de consumo de energia atingidas pelas técnicas propostas neste trabalho, conclui-se que o sistema de hierarquia de memória proposto nesta dissertação atinge seu objetivo de atender às restrições impostas pela codificação MVC, no que se refere ao processamento do módulo de ME/DE. / This Master Thesis proposes a memory hierarchy for the Motion and Disparity Estimation (ME/DE) centered on the encoding references, called Reference-Centered Data Reuse (RCDR), focusing on energy reduction in the Multiview Video Coding (MVC). In the MVC encoders the ME/DE represents more than 98% of the overall energy consumption. Moreover, in the overall ME/DE energy, up to 90% is related to the memory issues, and only 10% is related to effective computation. The two items to be concerned with: (1) off-chip memory communication to fetch the reference samples (45%) and (2) on-chip memory to keep stored the search window samples and to send them to the ME/DE processing core (45%). The main goal of this work is to jointly minimize the on-chip and off-chip energy consumption in order to reduce the overall energy related to the ME/DE on MVC. The memory hierarchy is composed of an onchip video memory (which stores the entire search window), an on-chip memory gating control, and a partial results compressor. A search control unit is also proposed to exploit the search behavior to achieve further energy reduction. This work also aggregates to the memory hierarchy a low-complexity reference frame compressor. The experimental results proved that the proposed system accomplished the goal of the work of jointly minimizing the on-chip and off-chip energies. The RCDR provides off-chip energy savings of up to 68% when compared to state-of-the-art. the traditional MBcentered approach. The partial results compressor is able to reduce by 52% the off-chip memory communication to handle this RCDR penalty. When compared to techniques that do not access the entire search window, the proposed RCDR also achieve the best results in off-chip energy consumption due to the regular access pattern that allows lots of DDR burst reads (30% less off-chip energy consumption). Besides, the reference frame compressor is capable to improve by 2.6x the off-chip memory communication savings, along with negligible losses on MVC encoding performance. The on-chip video memory size required for the RCDR is up to 74% smaller than the MB-centered Level C approaches. On top of that, the power-gating control is capable to save 82% of leakage energy. The dynamic energy is treated due to the candidate merging technique, with savings of more than 65%. Due to the jointly off-chip communication and on-chip storage energy savings, the proposed memory hierarchy system is able to meet the MVC constraints for the ME/DE processing.
212

Kostnadsbesparing med avseende på energieffektiviserande åtgärder med avgränsning till fönsterbyte och tilläggsisolering

Svensson, Fredrik, Bengtsson, Johan January 2018 (has links)
Sammanfattning 2017 års medelpris för el hamnade på cirka 30 öre per kWh. Det är åtta procent högre än för 2016 och hela 32 procent högre än 2015, då elpriset var väldigt lågt. 2017 års elpris är det högsta sedan 2013. Fortsättningsvis spår Bixia låga elpriser de kommande åren vilket beror på utbyggnaden av förnybar energi och att kärnkraftverket Olkilouto 3 i Finland tas i drift. Bixia räknar med att den nordiska elmarknaden kommer att ha en förstärkt energibalans fram till 2019. Efter år 2019 kommer energibalansen att försvagas, beroende på stängningen av Ringhals 1 och 2 och ökad export av el ut från Norden, säger Martina Rosenberg på Bixia. En försvagad energibalans innebär en högre prisnivå. Projektet syftar till att kartlägga omfattningen av energiförluster, i ett privat hushåll, till följd av transmission och därefter göra en bedömning om energibesparingsåtgärder, i form av tilläggsisolering och fönsterbyte, skulle vara en ekonomisk lönsam investering. Genom minskad energianvändning ger dessa investeringar ett positivt tillskott i energibalansen och kan även bidra till en bättre inomhusmiljö.   Projektet följer en metod där kvalitativa experiment har utförts genom mätningar på klimatskärmen. Denna mätning har gjorts med hjälp av en termografikamera där bilder har detekterat otätheter i klimatskärmen, så kallade köldbryggor. Energiförluster, till följd av transmission, har sedan beräknats med handberäkningsmetoder och utförts för en rad olika storheter, exempelvis värmeledningsmotstånd och värmegenomgångskoefficienter. Utöver detta har den specifika klimatskärmen delats upp i flera sektioner respektive skikt för att strukturerade beräkningar skulle kunna utföras enligt den beräkningsgång detta projekt efterföljt.   Undersökningen visar att åtgärderna bidrar till omkring 4 gånger mindre energiförluster gällande energifönster och 2 gånger mindre för väggen jämfört med värdena före åtgärder. Återbetalningstiden är dock betydligt längre för energifönstren då detta är en betydligt mer kostsam investering. För PVC-fönster landar återbetalningstiden på ca 27 år och för aluminiumbeklädda träfönster är återbetalningstiden i detta fall över 40 år mot ca 20 år för tilläggsisoleringen. / Abstract The 2017 average electricity price ended at around 30 Swedish “öre” per kWh. It is eight percent higher than in 2016 and 32 percent higher than in 2015, when the price for the electricity was much lower. The 2017 electricity price is the highest since 2013. Continuingly, Bixia's low electricity prices predict the next few years, which is due to the expansion of renewable energy and that the Olkilouto 3 nuclear power plant are put into use in Finland.   Bixia expects the Nordic electricity market to have a strengthened energy balance until 2019. After 2019, energy balance will weaken due to the closure of Ringhals 1 and 2 and increased exports of electricity from the Nordic countries, says Martina Rosenberg from Bixia. A weakened energy balance means a higher price level.   The project intention is to mapping the extent of energy losses, in a private household, due to transmission and subsequently assessing energy saving measures, in the form of additional insulation and exchange of windows, would be a profitable investment. Through reduced energy consumption, these investments provide a positive boost to the energy balance and can also contribute to a better indoor environment.   The project follows a method where qualitative experiments have been carried out through measurements on the climate screen. This measurement has been done by using a thermographic camera where images have detected thermal unevennesses in the climate screen that is called cold bridges. Energy losses due to transmission have then been calculated by hand calculation methods and performed for a variety of quantities, such as heat conductivity resistors and thermal coefficients. In addition, the specific climate screen has been divided into several sections and layers, so that structured calculations could be performed according to the calculation process followed by this project.   The survey shows that the measures contribute to is about 4 times less energy losses on energy windows and 2 times less for the wall than the pre-measure values. However, the repayment time is significantly longer for the energy windows, as this is a significantly more costly investment. For PVC windows, the repayment period is approximately 27 years. For aluminum clad wood windows, the repayment period in this case is over 40 years to about 20 years for the additional insulation.
213

Application specific programmable processors for reconfigurable self-powered devices

Nyländen, T. (Teemu) 27 April 2018 (has links)
Abstract The current Internet of Things solutions for simple measurement and monitoring tasks are evolving into ubiquitous sensor networks that are constantly observing both our well being and the conditions of our living environment. The oncoming omnipresent wireless infrastructure is expected to feature artificial intelligence capabilities that can interpret human actions, gestures and even needs. All of this will require processing power on a par with and energy efficiency far beyond that of the current mobile devices. The current Internet of Things devices rely mostly on commercial low power off-the-shelf micro-controllers. Optimized solely for low power, while paying little attention to computing performance, the present solutions are far from achieving the energy efficiency, let alone, the compute capability requirements of the future Internet of Things solutions. Since this domain is application specific by nature, the use of general purpose processors for signal processing tasks is counterintuitive. Instead, dedicated accelerator based solutions are more likely to be able to meet these strict demands. This thesis proposes one potential solution for achieving the necessary low energy, as well as the flexibility and performance requirements of the Internet of Things domain in a cost effective manner using reconfigurable heterogeneous processing solutions. A novel graphics processing unit-style accelerator for the Internet of Things application domain is presented. Since the accelerator can be reconfigured, it can be used for most applications of the Internet of Things domain, as well as other application domains. The solution is assessed using two computer vision applications, and is demonstrated to achieve an excellent combination of performance and energy efficiency. The accelerator is designed using an efficient and rapid co-design flow of software and hardware, featuring ease of development characteristics close to commercial off-the-shelf solutions, which also enables cost-efficient design flow. / Tiivistelmä Esineiden internet tulee muuttamaan tulevaisuudessa elinympäristömme täysin. Se tulee mahdollistamaan interaktiiviset ympäristöt nykyisten passiivisten ympäristöjen sijaan. Lisäksi elinympäristömme tulee reagoimaan tekoihimme ja puheeseemme sekä myös tunteisiimme. Tämä kaikkialla läsnä olevan langaton infrastruktuuri tulee vaatimaan ennennäkemätöntä laskentatehokkuutta yhdistettynä äärimmäiseen energiatehokkuuteen. Nykyiset esineiden internet ratkaisut nojaavat lähes täysin kaupallisiin "suoraan hyllyltä" saataviin yleiskäyttöisiin mikrokontrollereihin. Ne ovat kuitenkin optimoituja pelkästään matalan tehonkulutuksen näkökulmasta, eivätkä niinkään energiatehokkuuden, saati tulevaisuuden esineiden internetin vaatiman laskentatehon suhteen. Kuitenkin esineiden internet on lähtökohtaisesti sovelluskohtaista laskentaa vaativa, joten yleiskäyttöisten prosessoreiden käyttö signaalinkäsittelytehtäviin on epäloogista. Sen sijaan sovelluskohtaisten kiihdyttimien käyttö laskentaan, todennäköisesti mahdollistaisi tavoitellun vaatimustason saavuttamisen. Tämä väitöskirja esittelee yhden mahdollisen ratkaisun matalan energian kulutuksen, korkean suorituskyvyn ja joustavuuden yhdenaikaiseen saavuttamiseen kustannustehokkaalla tavalla, käyttäen uudelleenkonfiguroitavia heterogeenisiä prosessoriratkaisuja. Työssä esitellään uusi grafiikkaprosessori-tyylinen uudelleen konfiguroitava kiihdytin esineiden internet sovellusalueelle, jota pystytään hyödyntämään useimpien laskentatehoa vaativien sovellusten kanssa. Ehdotetun kiihdyttimen ominaisuuksia arvioidaan kahta konenäkösovellusta esimerkkinä käyttäen ja osoitetaan sen saavuttavan loistavan yhdistelmän energia tehokkuutta ja suorituskykyä. Kiihdytin suunnitellaan käyttäen tehokasta ja nopeaa ohjelmiston ja laitteiston yhteissuunnitteluketjua, jolla voidaan saavuttaa lähestulkoon kaupallisten "suoraan hyllyltä" saatavien prosessoreiden kehitystyön helppous, joka puolestaan mahdollistaa kustannustehokkaan kehitys- ja suunnittelutyön.
214

Kostnadsbesparing med avseende på energieffektiviserande åtgärder med avgränsning till fönsterbyte och tilläggsisolering / Cost savings with regard to energy efficiency measures with delimitation of window change and additional insulation

Svensson, Fredrik, Bengtsson, Johan January 2018 (has links)
Linnéuniversitetet Sjöfartshögskolan i Kalmar Utbildningsprogram:                                                                          Drift- och underhållsteknik Arbetets omfattning:                                                                         Självständigt arbete om 15 HP Titel:                                                                     Kostnadsbesparing med avseende på energieffektiviserande åtgärder med avgränsning till fönsterbyte och tilläggsisolering. Författare:                                                                                             Fredrik Svensson och Johan Bengtsson Handledare:                                                                                          Henrik Wärnberg   Sammanfattning 2017 års medelpris för el hamnade på cirka 30 öre per kWh. Det är åtta procent högre än för 2016 och hela 32 procent högre än 2015, då elpriset var väldigt lågt. 2017 års elpris är det högsta sedan 2013. Fortsättningsvis spår Bixia låga elpriser de kommande åren vilket beror på utbyggnaden av förnybar energi och att kärnkraftverket Olkilouto 3 i Finland tas i drift. Bixia räknar med att den nordiska elmarknaden kommer att ha en förstärkt energibalans fram till 2019. Efter år 2019 kommer energibalansen att försvagas, beroende på stängningen av Ringhals 1 och 2 och ökad export av el ut från Norden, säger Martina Rosenberg på Bixia. En försvagad energibalans innebär en högre prisnivå. Projektet syftar till att kartlägga omfattningen av energiförluster, i ett privat hushåll, till följd av transmission och därefter göra en bedömning om energibesparingsåtgärder, i form av tilläggsisolering och fönsterbyte, skulle vara en ekonomisk lönsam investering. Genom minskad energianvändning ger dessa investeringar ett positivt tillskott i energibalansen och kan även bidra till en bättre inomhusmiljö.   Projektet följer en metod där kvalitativa experiment har utförts genom mätningar på klimatskärmen. Denna mätning har gjorts med hjälp av en termografikamera där bilder har detekterat otätheter i klimatskärmen, så kallade köldbryggor. Energiförluster, till följd av transmission, har sedan beräknats med handberäkningsmetoder och utförts för en rad olika storheter, exempelvis värmeledningsmotstånd och värmegenomgångskoefficienter. Utöver detta har den specifika klimatskärmen delats upp i flera sektioner respektive skikt för att strukturerade beräkningar skulle kunna utföras enligt den beräkningsgång detta projekt efterföljt.   Undersökningen visar att åtgärderna bidrar till omkring 4 gånger mindre energiförluster gällande energifönster och 2 gånger mindre för väggen jämfört med värdena före åtgärder. Återbetalningstiden är dock betydligt längre för energifönstren då detta är en betydligt mer kostsam investering. För PVC-fönster landar återbetalningstiden på ca 27 år och för aluminiumbeklädda träfönster är återbetalningstiden i detta fall över 40 år mot ca 20 år för tilläggsisoleringen. / Linnaeus University Kalmar Maritime AcademyEducation programs:                                          Operation and MaintenanceScope of work:                                                    Independent work of 15 HPTitle:                                                                          Cost savings with regard to energy efficiency                                          measures with delimitation of window change and additional insulationAuthor:                                                                Fredrik Svensson and Johan Bengtsson Supervisor:                                                          Henrik Wärnberg Abstract The 2017 average electricity price ended at around 30 Swedish “öre” per kWh. It is eight percent higher than in 2016 and 32 percent higher than in 2015, when the price for the electricity was much lower. The 2017 electricity price is the highest since 2013. Continuingly, Bixia's low electricity prices predict the next few years, which is due to the expansion of renewable energy and that the Olkilouto 3 nuclear power plant are put into use in Finland.   Bixia expects the Nordic electricity market to have a strengthened energy balance until 2019. After 2019, energy balance will weaken due to the closure of Ringhals 1 and 2 and increased exports of electricity from the Nordic countries, says Martina Rosenberg from Bixia. A weakened energy balance means a higher price level.   The project intention is to mapping the extent of energy losses, in a private household, due to transmission and subsequently assessing energy saving measures, in the form of additional insulation and exchange of windows, would be a profitable investment. Through reduced energy consumption, these investments provide a positive boost to the energy balance and can also contribute to a better indoor environment.   The project follows a method where qualitative experiments have been carried out through measurements on the climate screen. This measurement has been done by using a thermographic camera where images have detected thermal unevennesses in the climate screen that is called cold bridges. Energy losses due to transmission have then been calculated by hand calculation methods and performed for a variety of quantities, such as heat conductivity resistors and thermal coefficients. In addition, the specific climate screen has been divided into several sections and layers, so that structured calculations could be performed according to the calculation process followed by this project.   The survey shows that the measures contribute to is about 4 times less energy losses on energy windows and 2 times less for the wall than the pre-measure values. However, the repayment time is significantly longer for the energy windows, as this is a significantly more costly investment. For PVC windows, the repayment period is approximately 27 years. For aluminum clad wood windows, the repayment period in this case is over 40 years to about 20 years for the additional insulation.
215

Efficient Fault Tolerance In Chip Multiprocessors Using Critical Value Forwarding

Subramanyan, Pramod 06 1900 (has links) (PDF)
Relentless CMOS scaling coupled with lower design tolerances is making ICs increasingly susceptible to transient faults, wear-out related permanent faults and process variations. Decreasing CMOS reliability implies that high-availability systems which were previously restricted to the domain of mainframe computers or specially designed fault-tolerant systems may be come important for the commodity market as well. In this thesis we tackle the problem of enabling efficient, low cost and configurable fault-tolerance using Chip Multiprocessors (CMPs). Our work studies architectural fault detection methods based on redundant execution, specifically focusing on “leader-follower” architectures. In such architectures redundant execution is performed on two cores/threads of a CMP. One thread acts as the leading thread while the other acts as the trailing thread. The leading thread assists the execution of the trailing thread by forwarding the results of its execution. These forwarded results are used as predictions in the trailing thread and help improve its performance. In this thesis, we introduce a new form of execution assistance called critical value forwarding. Critical value forwarding uses heuristics to identify instructions on the critical path of execution and forwards the results of these instructions to the trailing core. The advantage of critical value forwarding is that it provides much of the speed up obtained by forwarding all values at a fraction of the bandwidth cost. We propose two architectures to exploit the idea of critical value forwarding. The first of these operates the trailing core at lower voltage/frequency levels in order to provide energy-efficient redundant execution. In this context, we also introduce algorithms to dynamically adapt the voltage/frequency level of the trailing core based on program behavior. Our experimental evaluation shows that this proposal consumes only 1.26 times the energy of a non-fault-tolerant baseline and has a mean performance overhead of about 1%. We compare our proposal to two previous energy-efficient fault-tolerant CMP proposals and find that our proposal delivers higher energy-efficiency and lower performance degradation than both while providing a similar level of fault coverage. Our second proposal uses the idea of critical value forwarding to improve fault-tolerant CMP throughput. This is done by using coarse-grained multithreading to mul-tiplex trailing threads on a single core. Our evaluation shows that this architecture delivers 9–13% higher throughput than previous proposals, including one configuration that uses simultaneous multithreading(SMT) to multiplex trailing threads. Since this proposal increases fault-tolerant CMP throughput by executing multiple threads on a single core, it comes at a modest cost in single-threaded performance, a mean slowdown between11–14%.
216

Green Improvements: A Consumer's Guide to Environmentally and Economically Responsible Home Repairs and Improvements for the North Central Texas Region

Dickason, Deborah 08 1900 (has links)
The Consumer's Guide is designed to help consumers by providing guidelines for the purchase of specific energy-efficient household appliances- water heaters, air conditioning and heating systems, windows, dishwashers, refrigerators, clothes washers, and dryers. This serves two major purposes: to decrease the environmental impact of those products and to save consumers money over the lifetime of the products. The seven major appliances covered in this work are things that consumers tend to purchase quickly when their older models wear out and with little research into their energy and/or water efficiency. The guide begins with a general introduction and an explanation of the need for energy conservation. Explanations of how they work, purchasing tips, installation tips, maintenance tips, tips for additional energy efficiency, and case studies are given for each appliance. Printable pamphlets are included at the end.
217

Design and Implementation of Large-Scale Wireless Sensor Networks for Environmental Monitoring Applications

Yang, Jue 05 1900 (has links)
Environmental monitoring represents a major application domain for wireless sensor networks (WSN). However, despite significant advances in recent years, there are still many challenging issues to be addressed to exploit the full potential of the emerging WSN technology. In this dissertation, we introduce the design and implementation of low-power wireless sensor networks for long-term, autonomous, and near-real-time environmental monitoring applications. We have developed an out-of-box solution consisting of a suite of software, protocols and algorithms to provide reliable data collection with extremely low power consumption. Two wireless sensor networks based on the proposed solution have been deployed in remote field stations to monitor soil moisture along with other environmental parameters. As parts of the ever-growing environmental monitoring cyberinfrastructure, these networks have been integrated into the Texas Environmental Observatory system for long-term operation. Environmental measurement and network performance results are presented to demonstrate the capability, reliability and energy-efficiency of the network.
218

A cross-layer approach for optimizing the efficiency of wireless sensor and actor networks

Kohlmeyer, Eckhard Bernhard 25 June 2009 (has links)
Recent development has lead to the emergence of distributed Wireless Sensor and Actor Networks (WSAN), which are capable of observing the physical environment, processing the data, making decisions based on the observations and performing appropriate actions. WSANs represent an important extension of Wireless Sensor Networks (WSNs) and may comprise a large number of sensor nodes and a smaller number of actor nodes. The sensor nodes are low-cost, low energy, battery powered devices with restricted sensing, computational and wireless communication capabilities. Actor nodes are resource richer with superior processing capabilities, higher transmission powers and a longer battery life. A basic operational scenario of a typical WSAN application follows the following sequence of events. The physical environment is periodically sensed and evaluated by the sensor nodes. The sensed data is then routed towards an actor node. Upon receiving sensed data, an actor node performs an action upon the physical environment if necessary, i.e. if the occurrence of a disturbance or critical event has been detected. The specific characteristics of sensor and actor nodes combined with some stringent application constraints impose unique requirements for WSANs. The fundamental challenges for WSANs are to achieve low latency, high energy efficiency and high reliability. The latency and energy efficiency requirements are in a trade-off relationship. The communication and coordination inside WSANs is managed via a Communication Protocol Stack (CPS) situated on every node. The requirements of low latency and energy efficiency have to be addressed at every layer of the CPS to ensure overall feasibility of the WSAN. Therefore, careful design of protocol layers in the CPS is crucial in attempting to meet the unique requirements and handle the abovementioned trade-off relationship in WSANs. The traditional CPS, comprising the application, network, medium access control and physical layer, is a layered protocol stack with every layer, a predefined functional entity. However, it has been found that for similar types of networks with similar stringent network requirements, the strictly layered protocol stack approach performs at a sub-optimal level with regards to network efficiency. A modern cross-layer paradigm, which proposes the employment of interactions between layers in the CPS, has recently attracted a lot of attention. The cross-layer approach promotes network efficiency optimization and promises considerable performance gains. It is found that in literature, the adoption of this cross-layer paradigm has not yet been considered for WSANs. In this dissertation, a complete cross-layer enabled WSAN CPS is developed that features the adoption of the cross-layer paradigm towards promoting optimization of the network efficiency. The newly proposed cross-layer enabled CPS entails protocols that incorporate information from other layers into their local decisions. Every protocol layer provides information identified as beneficial to another layer(s) in the CPS via a newly proposed Simple Cross-Layer Framework (SCLF) for WSANs. The proposed complete cross-layer enabled WSAN CPS comprises a Cross-Layer enabled Network-Centric Actuation Control with Data Prioritization (CL-NCAC-DP) application layer (APPL) protocol, a Cross-Layer enabled Cluster-based Hierarchical Energy/Latency-Aware Geographic Routing (CL-CHELAGR) network layer (NETL) protocol and a Cross-Layer enabled Carrier Sense Multiple Access with Minimum Preamble Sampling and Duty Cycle Doubling (CL-CSMA-MPS-DCD) medium access control layer (MACL) protocol. Each of these protocols builds on an existing simple layered protocol that was chosen as a basis for development of the cross-layer enabled protocols. It was found that existing protocols focus primarily on energy efficiency to ensure maximum network lifetime. However, most WSAN applications require latency minimization to be considered with the same importance. The cross-layer paradigm provides means of facilitating the optimization of both latency and energy efficiency. Specifically, a solution to the latency versus energy trade-off is given in this dissertation. The data generated by sensor nodes is prioritised by the APPL and depending on the delay-sensitivity, handled in a specialised manor by every layer of the CPS. Delay-sensitive data packets are handled in order to achieve minimum latency. On the other hand, delay-insensitive non critical data packets are handled in such a way as to achieve the highest energy efficiency. In effect, either latency minimization or energy efficiency receives an elevated precedence according to the type of data that is to be handled. Specifically, the cross-layer enabled APPL protocol provides information pertaining to the delay-sensitivity of sensed data packets to the other layers. Consequently, when a data packet is detected as highly delay-sensitive, the cross-layer enabled NETL protocol changes its approach from energy efficient routing along the maximum residual energy path to routing along the fastest path towards the cluster-head actor node for latency minimizing of the specific packet. This is done by considering information (contained in the SCLF neighbourhood table) from the MACL that entails wakeup schedules and channel utilization at neighbour nodes. Among the added criteria, the next-hop node is primarily chosen based on the shortest time to wakeup. The cross-layer enabled MACL in turn employs a priority queue and a temporary duty cycle doubling feature to enable rapid relaying of delay-sensitive data. Duty cycle doubling is employed whenever a sensor node’s APPL state indicates that it is part of a critical event reporting route. When the APPL protocol state (found in the SCLF information pool) indicates that the node is not part of the critical event reporting route anymore, the MACL reverts back to promoting energy efficiency by disengaging duty cycle doubling and re-employing a combination of a very low duty cycle and preamble sampling. The APPL protocol conversely considers the current queue size of the MACL and temporarily halts the creation of data packets (only if the sensed value is non critical) to prevent a queue overflow and ease congestion at the MACL By simulation it was shown that the cross-layer enabled WSAN CPS consistently outperforms the layered CPS for various network conditions. The average end-to-end latency of delay-sensitive critical data packets is decreased substantially. Furthermore, the average end-to-end latency of delay-insensitive data packets is also decreased. Finally, the energy efficiency performance is decreased by a tolerable insignificant minor margin as expected. The trivial increase in energy consumption is overshadowed by the high margin of increase in latency performance for delay-sensitive critical data packets. The newly proposed cross-layer CPS achieves an immense latency performance increase for WSANs, while maintaining excellent energy efficiency. It has hence been shown that the adoption of the cross-layer paradigm by the WSAN CPS proves hugely beneficial with regards to the network efficiency performance. This increases the feasibility of WSANs and promotes its application in more areas. / Dissertation (MEng)--University of Pretoria, 2009. / Electrical, Electronic and Computer Engineering / unrestricted
219

Adaptive Two-Stage Edge-Centric Architecture for Deeply-Learned Embedded Real-Time Target Classification in Aerospace Sense-and-Avoidance Applications

Speranza, Nicholas A. 26 May 2021 (has links)
No description available.
220

Dětská léčebna se speleoterapií Ostrov u Macochy / Sanatorium with Speleotherapy for Childern Ostrov u Macochy

Rehák, Michal January 2015 (has links)
Designed children´s sanatorium is situated on the cadastral area of Ostrova u Macochy town, in the protected area of Moravsky Kras. The architecture of this building fits in the surroundings of the landscape and respects its features. The building main attributes are its south-facing slope, the compositional construction from prefabricated reinforced concrete structure and perimeter sandwich structure, as well as the massive insulation. Thanks to these characteristics, it is classified as energy-efficient building. These eight buildings, interconnected by the massive colonnade in its middle axis, force the user to take advantage of all its energy-efficient advantages.

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