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Inverkan av värmesystem på termisk komfort i ett flerbostadshus med hänsyn till energianvändning / Impact of heating systems on thermal comfort in a residential building with regard to energy useLarek, Adrian, Tran, Jimmy January 2015 (has links)
Inomhusklimatet har en avgörande roll för människans hälsa och välmående då människor befinner sig inomhus i nästan halva sitt liv. Det finns flera aspekter till hur det ska erhållas ett bra inomhusklimat men de mer betydelsefulla aspekterna är både god luftkvalitet och termisk komfort. Samtidigt som innebörden av reducering av energianvändning har en viktig roll i dagens utveckling. Då det ständigt arbetas med att försöka reducera energianvändningen i syfte till att underlätta för miljö- belastningen, väcker det frågor om hur den termiska komforten påverkas av detta. Rapportens syfte kommer därmed ligga i identifikation av uppvärmningssystem för ett givet flerbostadshus i Stockholmsområdet med fokus på termisk komfort och energianvändning. Utvärderingen baseras på olika typer av inverkan från diverse system som har utförts med beräkningssprogrammet IDA ICE. Ett referensfall för ett flerbostadshus användes som underlag och modellerades enligt A- och K-ritningar samt indata enligt Sveby. Det kommer även att inkludera de miljöcertifieringar som används i störst utsträckning här i Sverige och både ange deras krav gällande den termiska komforten samt respektive fokusområde då olika miljöcertifieringar har olika bedömningskriterier. Under denna studie visade det sig att det sällan tas hänsyn till den termiska komforten på motsvarande sätt som energianvändningen. Det har även visat sig att i de fall där krav gällande den termiska komforten finns, är den otillräckligt definierad för att ge en god uppfattning av komforten. Kraven tar, med andra ord, inte hänsyn till hur bra ett hus presterar under ett helt år utan fokuserar på ett momentant värde. Till simuleringen gjordes en känslighetsanalys som påvisade vikten och behovet av en tydlig standard för odefinierade variabler för att uttrycka människors bedömning av termisk komfort. Efter samtliga simuleringarna, granskades energiberäkningar efter erhållen granskningsmall från WSP Systems i syfte att utföra en egenkontroll samt ge ett underlag för rimlighetsbedömning. Från de erhållna resultaten visade det sig att golvvärme och ökad börvärde till 22 °C gav en ökad termisk komfort men samtidigt en ökning i energianvändningen medan FTX-systemet med radiatorer gav upphov till reducerad energianvändning med cirka en tredjedel samt en liten ökning av den termiska komforten. Det visade sig även vara att vid val av FTX-systemet gav högst årlig energibesparing men att det även bör tas hänsyn till installationskostnaderna för FTX-system och golvvärmesystemet till skillnad från om börvärdet ökas till 22 °C. Det blir då en kostnadsfråga och en avgörande parameter för val bland dessa tre systemen. / The indoor climate plays a crucial role in human health and well-being when people are indoors for nearly half their life. There are several aspects to how one should achieve good indoor climate, but the more significant aspects are both good air quality and thermal comfort. Simultaneously one must regard that the reduction of energy has an important role in today’s development. While trying to reduce energy consumption in order to facilitate the environmental load, it raises the questions whether the thermal comfort is affected by this. The purpose of the report will lie in the identification of a heating system for a given apartment building in the Stockholm area, with a focus on thermal comfort and energy use. The evaluation is based on various types of impacts from various systems that have been computed in IDA ICE. A reference case for an apartment building was used as a basis and was modeled according to architectural and constructional drawings while input data was used according to Sveby. It will also include the environmental certifications used in Sweden and specify their requirements regarding the thermal comfort, and each focus area as various environmental certifications have different assessment criteria’s. During this study it was found that we rarely take into account the thermal comfort in the same way we do with the energy consumption. It has also been found that in cases where the requirements for the thermal comfort exist, it is often insufficiently defined to provide one with a good perception of comfort. The requirements do, in other words, not take into account how well a building performs during a whole year but instead focuses on one instantaneous value. For the simulation a sensitivity analysis was made that revealed the importance and necessity of a clear standard for undefined variables to express the people’s assessment of thermal comfort. After the simulation part, the energy calculations were examined according to a review template from WSP Systems. This provided a basis for fair consideration. From the obtained results it was shown that floor heating and increasing the setpoint to 22 °C gave an increased thermal comfort but at the same time an increase in energy use. An HVAC system with a heat exchanger and radiators resulted in reduced energy use by about a third from the reference case and a slight increase in current thermal comfort. It also proved that the choice of an HVAC system with heat exchanger produced the highest annual energy savings. However one must take into account installation costs for different types of systems as opposed to when the setpoint is increased to 22 °C. Thus it becomes a cost issue and a critical parameter for selecting among these three types of solutions.
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Implementation and Evaluation of Bluetooth Low Energy for Musical Devices / Implementation och utvärdering av Bluetooth Low Energy för musikenheterLjungström, Andreas, Panikian, Jack January 2016 (has links)
This paper presents the possibility to transfer Musical Instrument Digital Interface messages overBluetooth Low Energy. The main problem was to transmit the messages between two computers inless than 10 milliseconds. Anything above 10 milliseconds could be noticed as a delay by the personplaying or listening to the music. A prototype was written which could transfer Musical InstrumentDigital Interface messages over Bluetooth Low Energy between two Linux-computers together with atesting framework which was used to make measurements. The prototype was written in the languageC++ with the BlueZ library. The time it took for one packet to travel back and forth from the computerswas clocked to get an estimation of the time it took for a packet to travel from one computer to theother. The measured results showed that it was possible to reach the desired time of 10 milliseconds.The results can also be used when considering development of other kind of equipment and/or applicationsthat implements the use of Bluetooth Low Energy. / Denna rapport presenterar möjligheterna att överföra Musical Instrument Digital Interfacemeddelanden över Bluetooth Low Energy. Huvudproblemet var att överföra meddelandena mellantvå datorer under en tid av 10 millisekunder. Allt över 10 milliskunder skulle kunna uppfattas somen fördröjning av den som spelade eller lystnade på musiken. En prototyp skapades som kundeöverföra denna typ meddelanden över Bluetooth Low Energy mellan två Linux-datorer tillsammansmed ett test-ramverk som kunde utföra prestandamätningar. Prototypen skrevs i språket C++tillsammans med biblioteket BlueZ. Den tid det tog för ett paket att färdas fram och tillbaka mellande båda datorerna klockades för att få en uppskattning på hur lång tid det tog för ett paket att färdasfrån en dator till en annan. De uppmätta resultaten visar att det är möjligt att uppnå deneftersträvade tiden på 10 millisekunder. Resultatet kan också användas då det övervägs att utvecklaett annat typ av program eller applikation som ska nyttja Bluetooth Low Energy.
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Study of the eikonal approximation to model exotic reactionsHebborn, Chloë 08 September 2020 (has links) (PDF)
In the mid-eighties, the development of radioactive-ion beams enabled the exploration ofregions of the nuclear landscape away from the valley of stability. Close to the neutrondripline, in the light neutron-rich region, halo nuclei were observed. These nuclei exhibit asurprisingly large matter radius and a strongly clusterized structure. These two featurescan be explained by the weak binding of one or two neutrons which allows them to tunnelfar from the rest of the nucleons, surrounding the nucleus by a diffuse halo. These nuclearstructures have challenged the usual description of the nucleus, described as a compactmany-body object with nucleons piling up into well defined orbitals. Because they areshort-lived, these nuclei are often studied through reaction processes, such as elasticscattering, breakup and knockout. To infer precise information from the experimentaldata, an accurate reaction model coupled with a realistic description of the nucleus isneeded.Compared to other state-of-the-art methods, the eikonal approximation is very cheapfrom a computational viewpoint. This model assumes that the projectile-target relativemotion does not differ much from the initial plane wave. It also makes the adiabaticapproximation, which sees the internal coordinates of the projectile as frozen during thecollision. These two assumptions hold for reactions occurring at high energy, i.e. above60 MeV/nucleon, in which the deflection of the projectile by the target is small and thecollision time is brief.In this thesis, I focus on improvements of the eikonal approximation. First, I studythe extension of the validity of the eikonal model down to 10 MeV/nucleon, in the energyrange of the facilities HIE-ISOLDE at CERN and ReA12 at the upcoming FRIB. To thisend, I analyse different corrections to the eikonal approximation, which account for thedeflection of the projectile by the target. I assess their accuracy for the elastic-scatteringand breakup observables of one-neutron halo nuclei at 10 MeV/nucleon. Next, I developa dynamical correction to the eikonal approximation, which applies to both nuclear andCoulomb interactions while conserving the eikonal numerical cost. I study this correctionin the cases of breakup reactions of one-neutron halo nuclei on light and heavy targets.Then, I investigate which nuclear-structure information can be inferred from knockoutreactions of one-neutron halo nuclei. To do so, I conduct a sensitivity analysis of theirobservables to the nuclear structure of the projectile, described within a halo effectivefield theory. In particular, I study the influence onto the cross sections of the ground-statewave function, the presence of subthreshold bound states and resonances. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished
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Dosimetric evaluation of the Acuros XB algorithm for a 4 MV photon beam in head and neck intensity-modulated radiation therapy. / 4MV-X線を用いた頭頸部強度変調放射線治療におけるAcuros XBアルゴリズムの物理的・臨床的線量評価Hirata, Kimiko 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20248号 / 医博第4207号 / 新制||医||1020(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 鈴木 実, 教授 別所 和久, 教授 大森 孝一 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Optical spectroscopy of cooperative phenomena and their symmetries in solidsMai, Thuc T. 19 June 2019 (has links)
No description available.
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BLUETOOTH-ENABLED ENERGY MONITORING SYSTEM WITH WIRELESS DATA ACQUISITION USING WEB SERVERWaikul, Devendra Mahendra 07 September 2020 (has links)
No description available.
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Analys av en Lågenergivilla i Falun : En unik villa med genomtänkta lösningar / Analysis of a low-energy house in Falun, SwedenPersson, Anton, Friberg, Simon January 2022 (has links)
Sverige har klimatmålet att nå negativa utsläpp av växthusgaser efter 2045 och det har en stor betydelse för att kunna uppnå Parisavtalet. Året 2021 stod bostäder och service för 43 % av den totala slutliga energianvändningen i Sverige och en minskning av den här användningen genom energieffektivisering är ett steg åt rätt riktning. Villa Ehrling byggdes 1982 i Falun och var tidigt ute med unika lösningar. I arbetet kartläggs de olika energieffektiviserande åtgärderna som förekommer i energivillan och energiberäkningar har genomförts över husets energiprestanda och klimatskal. Resultatet jämförs med dagens krav och andra lågenergihus för att avgöra om idéerna i villan kan implementeras än idag på nybyggnationer. Det primära syftet med villan är att utnyttja aktiv och passiv solenergi med vatten-och luftsolfångare samt lagra solenergi i villans stomme. Genom en unik utformning av fasaden med en 70 graders takvinkel, samt en orientering av byggnaden med stora glasspartier åt sydväst, kan värme tillföras från solinstrålningen under stora delar av året men också avskärmas under sommaren då solen står högre på himlen och värmebehovet är lägre. Utöver det har fasaden designats för att minska energiförluster från kall vind från norr med en låg takvinkel på 26 grader och begränsat antal fönsterytor. Villans ventilationssystem förvärmer tilluften genom lagrad värme i marken och återvinner värmen i frånluften. Överskottsvärmen kan lagras i ett stenmagasin under huset bestående av kullersten och tas ut när behovet finns. Ytterligare energieffektiviserande lösningar som förekommer i villan är återanvändandet av spillvärmen i avloppet med en avloppsvärmeväxlare. Resultatet av studien visar att villa Ehrling har en energiprestanda som varierar beroende på beteendet hos boende från omkring 35 % till 75 % lägre än de krav som ställs på nybyggnationer enligt Boverkets byggregler. Det här innebär att villan uppnår en hög energiklassificeringen med betygen A eller B än idag och hamnar i samma klassificering som andra lågenergihus. Byggnaden har en genomsnittlig värmegenomgångskoefficient på 0,314 W/(m2 K) vilket nästan uppfyller det högsta tillåtna värdet på denna koefficient idag. Jämfört med moderna lågenergihus fann den här studien att klimatskalet på villa Ehrling var mycket sämre. Slutsatsen från detta arbete är att trots villa Ehrling byggdes omkring 40 år sedan är det en villa som är mycket relevant än idag, både prestandamässigt och att mycket av husets energieffektiviserande lösningar är vanligt förekommande i nybyggnationer och andra lågenergihus idag. / Sweden has the goal of reaching negative emissions in the year 2045 to be able to reach the Paris agreement. In the year 2021, 43 % of the total energy consumption in Sweden came from housing and service and more efficient buildings is a step in the right direction. Villa Ehrling was built in 1982 in Falun, Sweden, with some interesting concepts. This report will present the concepts of the building and calculations that cover the performance of the house and its envelope. The results are compared with the requirement of how well insulated a house should be when built today. The performance and concepts of Villa Ehrling is also compared with other low-energy buildings to determine if some of Ehrlings concepts are of any use to implement in other buildings. The primary purpose of villa Ehrling is to utilize solar energy actively with air and water solar collectors, and passively by storing heat in building parts. A unique design of the façade, with and an orientation towards southwest with large areas of glass and a roof with an angle of 70 degrees, enables the ability to absorb solar heat during larger parts of the year and block the sun rays during summer when the heat demand is low. The façade contains small areas of glass towards northeast and a low roof angle of 26 degrees to reduce energy losses causes by cold winds.The ventilation system utilizes stored heat in the ground to preheat incoming air. The heat in the outflowing air is also utilized to preheat incoming air. Villa Ehrling has a heat storage made of cobblestone where energy is provided by heated air, and the energy can be extracted when the need occurs. Heat from showers and hot tap water usage is used in a heat exchanger and preheats tap water.The result of the study shows that villa Ehrling has an energy performance that varies depending on the behaviour of residents from about 35 % to 75 % lower than the requirements for new constructions according to the Swedish National Board of Housing, Building and Planning's building regulations. This means that the villa achieves a high energy classification with the grade A or B even today and ends up in the same classification as other low-energy houses. The building has an average heat transfer coefficient of 0.314 W/(m2 K), which almost meets the maximum permissible value of this coefficient today. Compared to modern low-energy houses, this study found that the envelope of villa Ehrling was much worse.The conclusion from this work is that despite villa Ehrling being built about 40 years ago, it is a villa that is very relevant even today, both in terms of the energy performance and that much of the house's energy efficient solutions are common in new buildings and other low-energy houses today.
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Bluetooth Mesh Networks: Evaluation of Managed Flooding in Different EnvironmentsHanna, Ayham, Assaf, Alaa January 2023 (has links)
Bluetooth Mesh networks have gained popularity across various industries, showcasing their significant impact on network solutions. This technology is particularly notable for its low power consumption, making it a preferred choice for efficient and sustainable network development. The objective of this study investigates the behavior of Bluetooth Mesh networks in various environments, aiming to improve network performance and provide guidance for optimal network design. This was achieved by performing experiments in multiple environments. Data collection and regression analysis along with comparative visualization were employed to understand the relationship between these variables, including distance, number of packets sent, environment, latency, and packet loss ratio. The results showed a significant relationship between distance and latency in the office and forest environments, as well as between distance and packet loss ratio in all environments. The number of packets sent has impact on latency and packet loss ratio. The findings contribute to the development of more reliable and efficient communication systems for Internet of Things applications, as well as providing insights into the performance characteristics of the Bluetooth Mesh network in various scenarios.
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Investigating the impact of physical layer transmission for Bluetooth LE AudioArponen, Kevin, Björkman, Axel January 2023 (has links)
Bluetooth Low Energy (BLE) is a widely used low-energy version of Bluetooth’swireless protocol. To meet increasing requirements of modern wireless audio devices,Bluetooth LE Audio was released with its new Low Complexity CommunicationsCodec (LC3) being much more data efficient than its predecessor Low Complexity SubBand Coding. Because of its increased data efficiency, LC3 opens the door of exploring usage ofvarious physical layer configurations, especially those with lower data rates. Thedifference in performance when streaming audio with the uncoded LE 2M and 1Mconfigurations, compared to using the LE coded S=2 and S=8 configurations (whichhave a lower throughput) points to a research gap which this thesis aims to fill. To be able to gather data necessary to fill the identified gap, multiple iterations of bothsoftware and hardware artefacts were made. The produced artefacts were designed torun the same Bluetooth version (LE Audio) and switch between the physical layerconfigurations. Throughput and current consumption in varied ranges was measuredthrough usage of the artefacts. The results from the experiments show that for energy optimization, an adaptive schemewould not be beneficial over only using LE 2M. However, an adaptive scheme for thephysical layer can be used for LE Audio to improve range and stability. This doeshowever, come with the cost of increased energy consumption.
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Stavba v krajině - Winery / Architecture in landscape - WineryVacková, Michaela January 2009 (has links)
The theme of my thesis deals with a winery near to the village Strachotín next to the Protected Landscape Area Pálava. It focuses, in particular, on the design of this object which serves not only to processing and producing of wine but also for degustation followed by the tour of wine production. Another part of my thesis is the design of accommodation, restaurant and wellness center by the means of using low-energy buildings, their various construction systems and natural materials. The whole conception is based on the overall potential of the territory, using the local sources and supporting the economic and social development of the area.
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