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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.
751

Utveckling av befintlig diskstolpe / Development of current washing post

Yousef, Aydin January 2020 (has links)
Argos mjölktank på Wedholms AB behöver utveckla vattenlåda med bättre säkerhet för el-kretsar på styrsystem samt reducera processtid för diskning av mjölktank.
752

Model Based System Consistency Checking Using Event-B

Xu, Hao 04 1900 (has links)
<p>Formal methods such as Event-B are a widely used approach for developing critical systems. This thesis demonstrates that creating models and proving the consistency of the models at the requirements level during software (system) development is an effective way to reduce the occurrence of faults and errors in a practical application. An insulin infusion pump (IIP) is a complicated and time critical system. This thesis uses Event-B to specify models for an IIP, based on a draft requirements document developed by the US Food and Drug Administration (FDA). Consequently it demonstrates Event-B can be used effectively to detect the missing properties, the missing quantities, the faults and the errors at the requirements level of a system development. The IIP is an active and reactive time control system. To achieve the goal of handling timing issues in the IIP system, we made extensions of an existing time pattern specified using Event-B to enrich the semantics of the Event-B language. We created several sets to model the activation times of different events and the union of these time sets defines a global time activation set. The tick of global time is specified as a progress tick event. All the actions in an event are triggered only when the global time in the time tick event matches the time specified in the event. Time is deleted from the corresponding time set, but not the corresponding global time set while the event is triggered. A time point is deleted from the global time set only when there are no pending actions for that time point. Through discharging proof obligations using Event-B, we achieved our goal of improving the requirements document.</p> / Master of Computer Science (MCS)
753

Compensating for Sound Delay as an Orchestral Percussionist : The Different Factors that Contribute to Correct Timing, and How They Correlate

Hembre, Even January 2024 (has links)
A research in how sound-delay needs to be compensated as an orchestral percussionist. Sound delay occurs when sound needs to travel from one location to another. The ionger the distance, the longer it takes for sound to arrive. Sound delay can occur when percussionists play from their position on a concert stage. Their position is usually furthest back on the stage, the backrow of the orchestra ensemble. This means that percussionists usually has the largest distance from the audience, in most settings. Observing and recording my own performance practises, reading existing written works and interviewing experienced percussionists has been the foundation for this research. By playing on multiple stations consisting of different percussion instruments in varying distances from a fellow musician in a performance practice, I could systematically observe how bodily movement changed between the varying distances in order to be on time with the colleague. The results of this research shows the complexity of sound delay compensation, and has shown that the topic includes more factors than expected. The sounding nature of the percussion instruments has, in this research, been observed to play a big part in the compensation of sound delay. / <p>Program:</p><p>"Prim" - Áskell Másson </p><p>"Shin-Kansen" - Bruno Hartl</p><p>"She who sleeps with a small blanket" - Kevin Volans</p><p>"Meditations a deux" - Ida Fahl</p><p>"Mistral" - Daniel Berg</p><p>"Cruisin`through fire" - Jackson Riffle</p><p></p><p>Colleagues:</p><p>Johannes Carlsson, percussion</p><p>Alexandru Munteanu, percussion</p><p>Tiago Rocha, percussion</p><p></p><p>Text-file no. 1: Thesis</p><p>Audio-file no. 1: Interview with Joakim Anterot</p><p>Audio-file no. 2: Interview with Mikael Nilsson</p><p>Audio-file no. 3: Interview with Roger Carlsson</p><p>Audio-file no. 4: Even Hembre`s Master-exam concert at KMH, 28th of May 2024</p><p>Video-file no. 1: Part 1 of Arne Björk`s "Symfonisk Duett" first performance</p><p>Video-file no. 2: Part 2 of Arne Björk`s "Symfonisk Duett first performance</p><p>Video-file no. 3: Part 3 of Arne Björk`s "Symfonisk Duett" first performance</p><p></p>
754

Conservation Banks : Analyzing the Commodification of Nature and the Effects on Biodiversity in the U.S.

Sindre, Josef January 2024 (has links)
In this thesis, the impact of conservation banking on biodiversity is assessed by examining the bird species richness in U.S. counties that have implemented the policy. Conservation banking is a market-based instrument designed for developers who need to comply with the Endangered Species Act for the negative environmental impacts that their projects have made. Conservation banking aims to “protect and recover imperilled species and the ecosystems upon which they depend” (USFWS 2013, p. 1). In this thesis, a staggered difference-in-difference with differential timing by Goodman-Bacon (2018) and further developed by Callaway and Sant’Anna (2021) is used to estimate the effect of conservation banks on biodiversity. Data for biodiversity, bird species richness are collected from U.S. Geological Survey's data from the North American Breeding Bird Survey (BBS). Information on conservation banks is gathered from the Regulatory In-lieu fee and Bank Information Tracking System (RIBITS). This thesis focuses on 107 conservation banks in 53 counties in the U.S. established between 2005 and 2016. The main results from this study indicate a positive impact of the introduction of conservation banks, with an increase in biodiversity of 4,1%. Consequently, this confirms the positive effect of the policy intervention. Despite these results, it is vital to consider caution regarding this market-based instrument. Market-based instruments that commodify elements of nature into the market are a new frontier in capitalist expansion. This approach may exclude areas from the natural evolutionary selection process, leading to potential long-term ecological imbalances. Current payment structures in conservation banking can lead to misallocation of taxpayers’ money at the same time as biodiversity outcomes are not optimized. Therefore, the most fundamental recommendation for this policy is to change to outcome-based payments.
755

Methodology to Assess Traffic Signal Transition Strategies Employed to Exit Preemption Control

Obenberger, Jon T. 24 March 2007 (has links)
Enabling vehicles to preempt the normal operation of traffic signals has the potential to improve the safety and efficiency of both the requesting vehicle and all of the other vehicles. Little is known about which strategy is the most effective to exit from preemption control and transition back to the traffic signals normal timing plan. Common among these traffic signal transition strategies is the method of either increasing or decreasing the cycle length of the signal timing plan, as the process followed to return to the coordination point of the effected signal timing plan, to coordinate its operation with adjacent traffic signals. This research evaluates commonly available transition strategies: best way, long, short, and hold strategies. The major contribution of this research is enhancing the methodology to evaluate the impacts of using these alternative transition strategies. Part of this methodology consists of the "software-in-the-loop" simulation tool which replicates the stochastic characteristics of traffic flow under different traffic volume levels. This tool combines the software from a traffic signal controller (Gardner NextPhase Suitcase Tester, version 1.4B) with a microscopic traffic simulation model (CORSIM, TSIS 5.2 beta version). The research concludes that a statistically significant interaction exists between traffic volume levels and traffic signal transition strategies. This interaction eliminates the ability to determine the isolated effects of either the transition strategies on average travel delay and average travel time, or the effects of changes in traffic volume levels on average travel delay and average travel time. Conclusions, however, could be drawn on the performance of different transition strategies for specific traffic volume levels. As a result, selecting the most effective transition strategy needs to be based on the traffic volume levels and conditions specific to each traffic signal or series of coordinated traffic signals. The research also concludes that for the base traffic volume and a 40% increase in traffic volume, the most effective transition strategies are the best way, long or hold alternatives. The best way was the most effective transition strategy for a 20% increase in traffic volume. The least effective strategy is the short transition strategy for both the base and 40% increase in traffic volume, and the long and short for a 20% increase in traffic volume. Further research needs to be conducted to assess the performance of different transition strategies in returning to coordinated operation under higher levels of traffic volume (e.g., approaching or exceeding congested flow regime), with varying cycle lengths, with different signal timing plans, and when different roadway geometric configurations (e.g., turn lanes, length of turn lanes, number of lanes, spacing between intersections) are present. / Ph. D.
756

Analyzing The Effectiveness of Electrical Stimulation (E-Stim) On Knee Injuries: Exploring The Optimal Timing of Use

Larenas, Briana M 01 January 2024 (has links) (PDF)
This paper investigates the importance of electrical stimulation (E-Stim) treatment pre- exercise, during exercise, and post-exercise on knee pain management and exercise performance on individuals with knee injuries. Common problems from which individuals experience pain and injuries are arthritis, ACL tears, and osteoarthritis. One therapeutic approach to address the pain has been electrical stimulation. This is a non-invasive treatment that introduces electrical currents into the injured tissue or muscle. However, there are several modalities of electrical stimulation treatment that include Transcutaneous Electrical Nerve Stimulation (TENS), Neuromuscular Electrical Stimulation (NMES), and Patterned Electrical Neuromuscular Stimulation (PENS). These treatments have the same goal: to provide a non-invasive method to stimulate the muscles and nerves to aid the healing process. Throughout this research, the populations targeted were females and males with age ranging from adolescents to older adults. The subjects were 15 – 75 years of age and had experienced knee injuries. They included athletes, older adults with osteoarthritis, and those who required arthroplasty. Between January 2023 and April 2024, the review of literature was conducted using UCF Libraries, PubMed, (MedLine), and SPORTDiscus (EBSCOhost). Keywords used included “TENS (Transcutaneous Electrical Nerve Stimulation) *”, “NMES (Neuromuscular Electrical Stimulation) *”, “osteoarthritis (OA)*”, Electrical Stimulation (E- Stim) *”, “knee injuries*”, “pain management*”, “before exercise*”, “after exercise*” and “during exercise*”. The results from these studies suggested that the application of e-stim was favored either during or after exercise.
757

Field Evaluation of the Eco-Cooperative Adaptive Cruise Control in the Vicinity of Signalized Intersections

Almannaa, Mohammed Hamad 27 July 2016 (has links)
Traffic signals are used at intersections to manage the flow of vehicles by allocating right-of-way in a timely manner for different users of the intersection. Traffic signals are therefore installed at an intersection to improve overall safety and to decrease vehicular average delay. However, the variation of driving speed in response to these signals causes an increase in fuel consumption and air emission levels. One solution to this problem is Eco-Cooperative Adaptive Cruise Control (Eco-CACC), which attempts to reduce vehicle fuel consumption and emission levels by optimizing driver behavior in the vicinity of a signalized intersection. Various Eco-CACC algorithms have been proposed by researchers to address this issue. With the help of vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) communication, algorithms are being developed that utilize signal phasing and timing (SPaT) data together with queue information to optimize vehicle trajectories in the vicinity of signalized intersections. The research presented in this thesis constitutes the third phase of a project that entailed developing and evaluating an Eco-CACC system. Its main objective is to evaluate the benefits of the newly developed Eco-CACC algorithm that was proposed by the Center for Sustainable Mobility at the Virginia Tech Transportation Institute. This algorithm uses advanced signal information (SPaT) to compute the fuel-optimal trajectory of vehicles, and, then, send recommended speeds to drivers as an audio message or implement them directly into the subject vehicle. The objective of this study is to quantitatively quantify the fuel-efficiency of the Eco-CACC system in a real field environment. In addition, another goal of this study is to address the implementation issues and challenges with the field application of the Eco-CACC system. A dataset of 2112 trips were collected as part of this research effort using a 2014 Cadillac SRX equipped with a vehicle onboard unit for (V2V) and (V2I) communication. A total of 32 participants between the ages of 18 and 30 were randomly selected from one age group (18-30) with an equal number of males and females. The controlled experiment was conducted on the Virginia Smart Road facility during daylight hours for dry pavement conditions. The controlled field experiment included four different scenarios: normal driving, driving with red indication countdown information provided to drivers, driving with recommended speed information computed by the Eco-CACC system and delivered to drivers, and finally automated driving (automated Eco-CACC system). The controlled field experiment was conducted for four values of red indication offsets along an uphill and downhill approach. The collected data were compared with regard to fuel economy and travel time over a fixed distance upstream and downstream of the intersection (820 ft (250 m) upstream of the intersection to 590 ft (180 m) downstream for a total length of 1410 ft (430 m)). The results demonstrate that the Eco-CACC system is very efficient in reducing fuel consumption levels especially when driving downhill. The field data indicates that the automated scenario could produce fuel and travel time savings of 31% and 9% on average, respectively. In addition, the study demonstrates that driving with a red indication countdown and recommended speed information can produce fuel savings ranging from 4 to 21 percent with decreases in travel times ranging between 1 and 10 percent depending on the value of red indication offset and the direction. Split-split-plot design was used to analyze the data and test significant differences between the four scenarios with regards to fuel consumption and travel time. The analysis shows that the differences between normal driving and driving with either the manual or automated Eco-CACC systems are statistically significant for all the red indication offset values. / Master of Science
758

Knock Sensor-based Estimation for Valve Events / Knackgivarbaserad uppskattning av ventilöppning och ventilstängning

Wang, Yuxiao January 2024 (has links)
For diesel engines, valve timing is important and is related to power efficiency and exhaust gas after-treatment. During operation, the temperature of engine components can change and thus influencing the actual valve timing. With collected data from a Scania experimental engine, a method for valve closing time detection based on knock sensors is proposed in this project using a signal processing method. For algorithm design and result evaluation purposes, two references are used in this project. One is nominal valve timing, and the other is a valve timing reference based on rocker arm force signals. The developed method is tested through 4 evaluations: (1) 30% engine load with different engine speeds (600 to 2000rpm), (2) 1200rpm engine speed with different engine loads (0 to 100%), (3) 40% load 1200rpm at different oil temperature (around 50 to 80°C), and (4) 40% load dropped to motored condition. By comparing evaluation results and previously reported data, the following conclusions can be drawn: (a) The developed method has the ability to catch the changing of valve closing time in most test cases; (b) The developed method has a maximum combined error (between detected valve closing and rocker arm unloaded time) of - 4.7CAD on the intake side and -12.6CAD on the exhaust side among all cylinders; (c) Due to interference from vibration caused by valve events of other cylinders, the developed method has worse accuracy with larger than 50% load. Further work can focus on the detection of valve opening time and the improvement of accuracy by finding better sensor positions. / För dieselmotorer är ventiltidpunkten viktig och relaterad till energieffektivitet och avgasefterbehandling. Under drift kan temperaturen på motorkomponenterna förändras och därmed påverka ventilernas faktiska timing. Med insamlade data från en Scania experimentell motor föreslås i detta projekt en metod för detektering av ventilstängningstid baserad på knackgivare med hjälp av en signalbehandlingsmetod. För algoritmdesign och resultatutvärdering används två referenser i detta projekt. Den ena är nominell ventiltidpunkt och den andra är en ventiltidsreferens baserad på vipparmskraftssignaler. Den utvecklade metoden testas genom 4 utvärderingar: (1) 30% motorbelastning med olika motorvarvtal (600 till 2000r/min), (2) 1200r/min motorvarvtal vid olika motorbelastningar (0 till 100%), (3) 40% belastning 1200r/min vid olika oljetemperatur (runt 50 till 80 °C), och (4) 40% belastning till motordrivet tillstånd. Genom att jämföra utvärderingsresultat och tidigare rapporterade data kan följande slutsatser dras: (a) Den utvecklade metoden har förmågan att fånga ändring av ventilstängningstiden i de flesta testfall; (b) Den utvecklade metoden har ett maximalt kombinerat fel (mellan detekterad ventilstängning och vipparmslasttid) på -4,7CAD på inloppssidan och -12,6CAD på avgassidan bland alla cylindrar. (c) På grund av vibrationsstörningar orsakade av ventilhändelser hos andra cylindrar har den utvecklade metoden sämre noggrannhet med större än 50% last. Det fortsatta arbetet kan fokusera på detektering av ventilernas öppningstid, förbättring av noggrannheten genom att hitta bättre givarpositioner.
759

The effect of a perceptual-motor training programme on the coincident anticipation timing and batting performance of club cricket players

Van Velden, Grant David 12 1900 (has links)
Thesis (M Sport Sc (Sport Science)-- University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The purpose of this study was to determine the effects of a perceptual-motor training programme on the coincident anticipation timing and batting performance of university club cricket players. The intervention programme focused on developing players‟ visual attention and concentration. Vickers‟ (2007) Three-Step Decision Training Model was used to structure the training sessions. The study followed a repeated measures experimental design with three groups (experimental, placebo, and control) formed by volunteers from a university club cricket team. The independent variable was a four-week training programme. The dependent variables were coincident anticipation timing and performance on a cricket batting test. Subjects were pre- and post-tested with retention tests occurring after a set period of “no training” following the post-tests. Differences between groups were compared using Kruskal-Wallis ANOVA by Ranks Tests. Differences within each group were compared using multiple Mann-Whitney U-Tests. No significant improvements were observed in the experimental group‟s coincident anticipation timing and batting performance. Although neither coincident anticipation timing nor batting performance significantly improved, further research into the use of Vickers‟ (2007) Model to enhance sport performance is recommended. / AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die uitwerking van ʼn perseptueel-motoriese opleidingsprogram op die samevallende vooruittydsberekening (“coincident anticipation timing”) en kolfprestasie van universiteitsklubkrieketspelers te bepaal. Die klem van die intervensieprogram het op die ontwikkeling van spelers se visuele aandag en konsentrasie geval. Die opleidingsessies is volgens Vickers (2007) se drieledige model vir besluitnemingsopleiding saamgestel. Die studie het ʼn eksperimentele ontwerp van herhaalde metings op drie groepe (eksperimenteel, plasebo en kontrole) van ʼn universiteitsklubkrieketspan toegepas. Die onafhanklike veranderlike was ʼn vier weke lange opleidingsprogram. Die afhanklike veranderlikes was samevallende vooruittydsberekening, en prestasie in ʼn krieketkolftoets. Proefpersone het voor en net ná die opleiding toetse ondergaan, sowel as behoudtoetse drie weke ná die na-opleidingstoetse. Verskille tussen groepe is met behulp van rangtoetse uit Kruskal-Wallis se variansie-analisemodel (ANOVA) bepaal, terwyl verskille binne groepe met veelvuldige Mann-Whitney-U-toetse vergelyk is. Geen beduidende verbetering is in die eksperimentele groep se samevallende vooruittydsberekening of kolfprestasie waargeneem nie. Hoewel nóg samevallende vooruittydsberekening nóg kolfprestasie aansienlik verbeter het, word verdere navorsing oor die gebruik van Vickers (2007) se model vir die verbetering van sportprestasie aanbeveel.
760

我國共同基金擇時效果之評估

楊誌柔, YANG, ZHI-ROU Unknown Date (has links)
我國股票市場,向以規模太小(截至77年四月底上市公司僅140餘家)而為人詬 病,如:太容易經由大戶的抄作,使散戶套牢而遭受損失,故擴大股票市場規模及增 加機構投資者比重,向為政府努力的目標。 72年財政部證卷管理委員會先後制定發佈了「證卷投資信託事業管理規則」及「證 卷投資信託基金管理辦法」期能以增加機構投資方式,避免股市過於投機,又使社會 游資有良孚出路,至76年底國內共有四家證卷投資信託公司:國際、光華、建弘及 中華。每家公司分別掌管了兩個基金(國內及國外各一)。 本論文以此八個基金為研究對象,研究期間從72.10.29∼76.12.29 .,以各基金與市場股票指數的週報酬率為比較基礎,先計算各基金的sharpe(19 66),Treynor (1965),Jensen(1968)的指數,以排名先後,再以 Henriksson(1984)及Moses (1987)的迴歸模式來探討各基金的擇時效果 (selection and Timing)。 擇時效果乃Fama(1972)提出,利用資本市場線(SML)模式來惟算,簡而言 之,選擇效果乃評估基金選股的優勢,而時間效果則衡量基金報酬是否優於市場報酬 。 研究結果sharpe,Treynor 及Jensen指數,各國基金互有優劣,但以光華國外基金略 佳,至於選擇效果各基金皆無明顯表現,而時間效果則僅有光華國外基金略佳,其餘 基金時間效果皆低於市場報酬。 本研究因受限於各基金成立時間不一,且在研究期間並不長久下,所得出的績效排名 ,難免有失偏頗。唯提出基金績效的評估模式,以給欲購買「受益憑證」的投資大眾 ,有個參考!

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