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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.
41

VEHICLE MONITORING SYSTEM VIA GPS, GIS AND GPRS

Lei, Huang, Qishan, Zhang, Xingjian, Huang 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Vehicle Monitoring System (VMS) has being introduced into the world marketplace with the hope that it will help alleviate traffic congestion and the associated environmental pollution. In this paper we give an overview of system composition and principle of the VMS and several communications link solutions in China. We review technologies and focus on the key technological issues about the integration of VMS with the GPRS wireless mobile network and the Internet.
42

Efectividad de un módulo educativo sobre el nivel de conocimientos de sexualidad, prevención de infecciones de transmisión sexual y VIH/sida de los estudiantes de tercer año de secundaria-institución educativa República de Colombia-2014

Dueñas Mera, Milagros Elizabeth January 2015 (has links)
Objetivo: Determinar la efectividad de un módulo educativo sobre el nivel de conocimientos de sexualidad, prevención de infecciones de transmisión sexual y VIH/SIDA de los estudiantes de tercer año de secundaria de la Institución educativa República de Colombia-2014. Método: Estudio experimental aplicativo, diseño pre experimental tipo pre prueba y pos prueba de un solo grupo, cuyo instrumento utilizado fue un cuestionario de 21 preguntas cerradas aplicados antes y después de la intervención. La población lo constituyó el total de adolescentes de la Institución Educativa, la que asciende a 430 alumnos, el tipo de muestreo no probabilística por conveniencia, en este caso estudiantes de tercer año de secundaria; después de recolectar la información se procesó en paquetes estadísticos de Excel y SPSS. Resultados: Los conocimientos sobre sexualidad, infecciones de trasmisión sexual y VIH/ SIDA, antes de la intervención educativa el 86% de encuestados poseía un nivel de conocimiento medio y sólo el 6% un nivel alto; resultado que logró incrementarse a 94% con un nivel de conocimiento alto, con una alta significación estadística p<0.05. Conclusiones: Se ha demostrado la efectividad del “Módulo educativo, Conversando con los adolescentes de estilos de vida saludables, sexualidad y prevención de ITS/ VIH Y SIDA”, el 94% de encuestados incrementó el nivel de conocimientos de 12.57 a 19.39, así como de nivel bajo-medio pasando a un nivel alto. / ---Objective: To determine the effectiveness of an educational module on the level of knowledge about sexuality , prevention of sexually transmitted diseases and HIV / AIDS of the students of junior year educational Institution Republic of Colombia 2014 Method: Experimental study application, pre experimental design pretest and post-test type of a single group, the instrument used was a questionnaire of 21 closed questions applied before and after the intervention. The population was constituted by all the adolescents in the educational institution, which amounts to 430 students, the type of non-probability sampling for convenience, in this case students of junior year; after collecting the information was processed in Excel and statistical packages SPSS. Results: The knowledge about sexuality, sexually transmitted infections and HIV / AIDS, before the educational intervention, 86% of respondents had an average level of knowledge and only 6% a high level; result achieved increased to 94% with a high level of knowledge, with high statistical significance p <0.05. Conclusions: We demonstrated the effectiveness of "educational module, Talking with teens healthy lifestyles, sexuality and prevention of STIs / HIV and AIDS," 94% of respondents increased the knowledge level of 12.57 to 19.39, and Low-average spending at a high level. Keywords: Educational Module, effectiveness, knowledge, sexuality, STIs, HIV and AIDS / Tesis
43

Ecology Of Composted Bedded Pack And Its Impact On The Udder Microbiome With An Emphasis On Mastitis Epidemiology

Andrews, Tucker 01 January 2019 (has links)
Infections of the cow udder leading to mastitis and lower milk quality are a critical challenge facing northeast organic dairy farmers. Limited mastitis treatment options are available to organic producers and bedding systems impact cow health, including mastitis risk. Composted bedded pack, a system touted for increased cow comfort and well-being, allows stratified accumulation of bedding and manure in the barn. This method is gaining popularity among organic producers, yet little is known about the microbiota of the accumulated pack and its interaction with the cow mammary gland. An in-depth single farm study was conducted that surveyed bedded pack (microbiome and microarthropod community), dipteran vectors of bacterial mastitis pathogens, and the teat skin and teat cistern milk microbiomes. Comparisons were made with four additional farms utilizing bedded packs to test generality of results. Few fly pests were observed in the bedded pack. However, bedding on all farms was found to harbor the mesostigmatid mite genus Glyptholaspis, a well-established predator of nematodes and muscid fly larvae, suggesting that predators may suppress populations of biting flies in bedded pack barns. Additionally, the fungivorous genus Rhizoglyphus was commonly abundant in all farms, suggesting that the mite community regulates microbial activity at multiple trophic levels. High-throughput sequencing of universal marker genes for bacterial and fungal communities was used to characterize the skin and milk microbiome of cows with both a healthy and infected quarter on the case study farm, and the composted bedded pack of all five farms. The bedded pack microbiome varied with bedding material and management style; fungal taxa were primarily yeasts of the Ascomycota; all farms additionally contained anaerobic fungi associated with the bovine rumen. Common bacterial genera included Acinetobacter and Pseudomonas, both of which were also commonly observed on teat skin and in milk. The udder microbiome varied through time and between skin and milk. Both healthy and infected milk microbiomes reflected a diverse group of microbial DNA sequences. Health status of the quarter changed whether taxa were shared between the teat skin, milk, and bedding. Proportion of taxa shared between healthy milk and skin was stable while taxa shared in infected quarters varied widely. Taxa shared among all habitats included yeast genus Debaryomyces and bacteria Acinetobacter guillouiaea. Results support an ecological interpretation of both the udder and the bedded pack environment and support the notion that mastitis can be described as an imbalance of the healthy mammary gland microbiome. Future work might compare udder health between common bedding practices, investigating the impact of bedding on the microbiota of the mammary gland in the healthy and diseased state.
44

Nontradable Market Index and Its Derivatives

Xu, Peng 30 July 2009 (has links)
The S&P 500 Index is a leading indicator of U.S. equities and is meant to reflect the risk and return on the U.S. stock market. Many derivatives based on the S&P 500 are available to investors. The S&P 500 Futures of the Chicago Mercantile Exchange and the S&P 500 Index Options of the Chicago Board Options Exchange are both actively traded. My thesis argues that the S&P 500 Index is only a summary statistic designed to reflect the evolution of the stock market. It is not the value of a self-financed tradable portfolio, and its modifications do not coincide with changes of the value of any mimicking portfolio, due to the particular way the S&P 500 Index is computed and maintained. Therefore, the Spot-Futures Parity and the Put-Call Parity do not hold for the S&P 500 Index and its derivatives. Furthermore, its derivatives cannot be priced by using the standard option pricing models, which assume that the underlying asset is tradable. Chapter One analyzes why the S&P 500 Index does not represent the value of a self-financed tradable portfolio and why it cannot be replaced by the value of a tracker such as the SPDR. In particular, we show that the nonlinear and extreme risk dynamics of the SPDR and of the S&P 500 Index are very different. Chapter Two provides empirical evidence that the non-tradability of the S&P 500 Index can explain the Put-Call Parity deviations. Even after controlling for the liquidity risk of the options, we find that the Put-Call Parity implied dividends depend significantly on the option strike. In Chapter Three, we develop an affine multi-factor model to price coherently various derivatives such as forwards and futures written on the S&P 500 Index, and European put and call options written on the S&P 500 Index and on the S&P 500 futures. We consider the cases when the underlying asset is self-financed and tradable and when it is not, and show the difference between them. When the underlying asset is self-financed and tradable, an additional arbitrage condition has to be introduced and implies additional parameter restrictions.
45

Nontradable Market Index and Its Derivatives

Xu, Peng 30 July 2009 (has links)
The S&P 500 Index is a leading indicator of U.S. equities and is meant to reflect the risk and return on the U.S. stock market. Many derivatives based on the S&P 500 are available to investors. The S&P 500 Futures of the Chicago Mercantile Exchange and the S&P 500 Index Options of the Chicago Board Options Exchange are both actively traded. My thesis argues that the S&P 500 Index is only a summary statistic designed to reflect the evolution of the stock market. It is not the value of a self-financed tradable portfolio, and its modifications do not coincide with changes of the value of any mimicking portfolio, due to the particular way the S&P 500 Index is computed and maintained. Therefore, the Spot-Futures Parity and the Put-Call Parity do not hold for the S&P 500 Index and its derivatives. Furthermore, its derivatives cannot be priced by using the standard option pricing models, which assume that the underlying asset is tradable. Chapter One analyzes why the S&P 500 Index does not represent the value of a self-financed tradable portfolio and why it cannot be replaced by the value of a tracker such as the SPDR. In particular, we show that the nonlinear and extreme risk dynamics of the SPDR and of the S&P 500 Index are very different. Chapter Two provides empirical evidence that the non-tradability of the S&P 500 Index can explain the Put-Call Parity deviations. Even after controlling for the liquidity risk of the options, we find that the Put-Call Parity implied dividends depend significantly on the option strike. In Chapter Three, we develop an affine multi-factor model to price coherently various derivatives such as forwards and futures written on the S&P 500 Index, and European put and call options written on the S&P 500 Index and on the S&P 500 futures. We consider the cases when the underlying asset is self-financed and tradable and when it is not, and show the difference between them. When the underlying asset is self-financed and tradable, an additional arbitrage condition has to be introduced and implies additional parameter restrictions.
46

Mobila IT-tjänster och Intelligenta transportsystem (ITS) - framtidsperspektiv 2009 och konsekvenser för Vägverket

Holmén, Sara January 2004 (has links)
Uppdragsgivare till detta examensarbete var Vägverkets ITS-avdelning. Vägverket ska vara en möjliggörare för tjänster inom ITS-området, och detta arbete beskriver de mobila ITtjänster inom ITS som tros finnas år 2009. Det är också viktigt att se hur den nationella vägdatabasen, NVDB, möter de framtida kraven från de mobila IT-tjänsterna. Detta eftersom NVDB är en grunddatabas över det data Vägverket tillhandahåller och möjliggör utveckling av mobila IT-tjänster och det är därför viktigt att den innehåller korrekt och uppdaterad data.Under detta arbete har jag jobbat med två metoder, litteraturstudier och kvalitativa intervjuer. Litteraturstudier har jag använt för att sätta mig in i Vägverkets ITS-strategi, mål, pågående ITS-projekt i Sverige och Europa och framtidsvisionärers idéer om framtidens samhälle och ITS. Intervjuerna gjorde jag med personer som arbetar inom ITS eller IT, för att få deras synpunkter om möjliga framtida mobila IT-tjänster inom ITS.Resultatet pekar på att de framtida mobila IT-tjänsterna kommer vara positioneringstjänster av olika slag. Många anser idag att det är svårt att få information om grundläggande vägdata, som t.ex. köer, olyckor och vägbeskrivning. Utrustningen som kommer att användas tros av majoriteten av de intervjuade att vara mobiltelefonerna, men de kommer vara mer avancerade än de är idag. För att förbättra NVDB för att få igång tjänsteutvecklingen är det viktigt att alla kommunala och statliga vägar finns med, vilket det inte gör idag. Dokumentationen kring NVDB ansågs också komplicerad.
47

ITS och Logistik : Skogsåkeriernas behov av väg- och trafikinformation jämfört med Vägverkets tillhandahållna information

Pers Lindberg, Catherine January 2004 (has links)
Jag har i detta examensarbete analyserat behovet av väg- och trafikinformation i samband med skogstransporter och jämfört behovet med den information som Vägverket tillhandahåller. Arbetet har utförts på uppdrag av Vägverkets ITS-sektion, den avdelning som ansvarar för Vägverkets uppdrag att öka användningen av IT i trafiken. Målet med arbetet har varit att undersöka hur väg- och trafikinformation kan bidra till bättre skogstransporter och bättre trafik. Syftet har varit att ta reda på hur en perspektivväxling mellan trafik och transport påverkar tjänsteutvecklingen när det gäller väg- och trafikinformation. De metoder jag har använt har varit kvalitativa intervjuer, litteratur- och dokumentstudier samt komponenterna problem- och målanalys i metoden Förändringsanalys enligt FA/SIMM. Det i särklass största informationsbehovet vid utförandet av en skogstransport är statusen på den aktuella vägen vid transporttillfället. Bristfällig information i detta sammanhang är information om bärighetsnedsättningar på grund av tjällossning samt information om vägunderhåll (snöplogning, saltning och sandning) under vintern. Som ett resultat av detta arbete har jag därför föreslagit två nya system/tjänster för att hantera denna information. Eftersom en transport sker från en punkt till en annan är det min uppfattning att väg- och trafikinformationen bör paketeras i en tjänst med denna utgångspunkt, till skillnad från dagens tjänster som utgår från en viss geografisk plats.
48

Multi-sensor Data Fusion for Traffic Speed and Travel Time Estimation

Bachmann, Christian 01 December 2011 (has links)
In this thesis, seven multi-sensor data fusion based estimation techniques are investigated. All methods are compared in terms of their ability to fuse data from loop detectors and Bluetooth tracked probe vehicles to accurately estimate freeway traffic speed. In the first case study, data generated from a microsimulation model are used to assess how data fusion might perform with present day conditions, having few probe vehicles, and what sort of improvement might result from an increased proportion of vehicles carrying Bluetooth-enabled devices in the future. In the second case study, data collected from the real-world Bluetooth traffic monitoring system are fused with corresponding loop detector data and the results are compared against GPS collected probe vehicle data, demonstrating the feasibility of implementing data fusion for real-time traffic monitoring today. This research constitutes the most comprehensive evaluation of data fusion techniques for traffic speed estimation known to the author.
49

Multi-sensor Data Fusion for Traffic Speed and Travel Time Estimation

Bachmann, Christian 01 December 2011 (has links)
In this thesis, seven multi-sensor data fusion based estimation techniques are investigated. All methods are compared in terms of their ability to fuse data from loop detectors and Bluetooth tracked probe vehicles to accurately estimate freeway traffic speed. In the first case study, data generated from a microsimulation model are used to assess how data fusion might perform with present day conditions, having few probe vehicles, and what sort of improvement might result from an increased proportion of vehicles carrying Bluetooth-enabled devices in the future. In the second case study, data collected from the real-world Bluetooth traffic monitoring system are fused with corresponding loop detector data and the results are compared against GPS collected probe vehicle data, demonstrating the feasibility of implementing data fusion for real-time traffic monitoring today. This research constitutes the most comprehensive evaluation of data fusion techniques for traffic speed estimation known to the author.
50

Realaus laiko transporto maršrutų optimizavimo algoritmų tyrimas / Research of real time vehicle routing optimization algorithms

Razminas, Simonas 03 June 2006 (has links)
Nowadays traffic congestion is a big problem all over the world. To solve this problem governments build broader roads, establish more reasonable traffic rules. Dynamic routing is a good and efficient way to reduce traffic congestion. That is why research of real time vehicle routing optimization algorithms was made. Experiment showed that best performance of shortest path algorithm was Dijkstra algorithm. Based on that, a software prototype was developed – optimized route search system. Driver can select shortest or fastest route to his destination. There was used roads length to evaluate shortest path and special coefficient to evaluate fastest route. This coefficient is calculated respectively to road load, length, speed limit, capacity. Performance of developed system is good so I conclude that the system is capable of routing vehicles in real time in complex traffic network.

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