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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.
101

Isolation and characterization of a microorganism from groundwater that reduces arsenate /

McCaffery, Kevin A., January 2002 (has links)
Thesis (M.S.) in Civil Engineering--University of Maine, 2002. / Includes vita. Includes bibliographical references (leaves 76-85).
102

Studies on the reproductive cycle of the female cobra, Naja naja (L.).

Lance, Valentine Anthony, January 1973 (has links)
Thesis--Ph. D., University of Hong Kong. / Typewritten.
103

An evaluation of the classroom implementation of the Water Exploration Legacy Cycle : an online challenge-based educational program for Texas high school students / Online challenge-based educational program for Texas high school students

Mueller, Elizabeth Pelly 27 February 2012 (has links)
In this paper we sought to evaluate the implementation of the Water Exploration Legacy Cycle, a research collaborative project developed by the Institute for Geophysics at The University of Texas at Austin and 4empowerment.com with support from the Texas Water Development Board. This project interviewed six teachers of the 22 science educators who attended a workshop to learn about the Legacy Cycle approach and how to implement the Water Exploration Legacy Cycle curriculum in August of 2010. The research involved a survey and a phone interview, both of which collected data on the training session, the teachers’ abilities to work with the Legacy Cycle within their curriculum, and obstacles they faced with full implementation of the program. Recommendations from this study will aid future developers in creating Legacy Cycle modules that are better adapted to high school classrooms. / text
104

Indicators of Phase Transition within the Vehicle’s Lifecycle : A Case Study of Scania

Scaglia, Anna-Giulia, Persson, Vickie January 2015 (has links)
The total lifecycle of a vehicle contains many phases, from production to sales to first customer to second customer and so on until the end of life. Each one of these phases includes different activities in different business areas and under different conditions. This means that the customers´ needs will vary depending on which lifecycle phase the vehicle is in and the offered services have to be adapted to this. Therefore it is important for truck developing companies to know when a transition, from one lifecycle phase to another has occurred. This study is based on a case study provided by Scania, a company that develops trucks and busses. Delimitations were that the study would focus on connected long-haulage trucks that are in Europe under their first life cycle phase, that the developed services would be described on a conceptual level and not cover any economic aspects. With this in mind, the following research questions were created: RQ1) What defines a transition phase? RQ2) How can the long-haulage trucks’ usage pattern be used to identify a transition phase? RQ3) Which data is needed to identify a transition phase? RQ4) Based on the results of RQ2 and RQ3, how could the transition alert service be designed? RQ5) Which applications could the transitions alert service be used for? The study included a literature study covering product lifecycle theory, servicification, second-hand market, big data, telematics, intelligent vehicles and statistic hypothesis testing. Further, two truck drivers were observed in order to get better understanding of the transportation business and the truck driving activities. Two qualitative interview studies were made with hauliers, service salesmen, truck salesmen and distributors from Czech Republic, Denmark, Italy, Poland, Spain and Sweden. The results of the empirical studies were analysed and RQ1 could be answered. Transition phase is the period between two different vehicle owners and/or two different ways of utilizing the truck. The analysis also gave a good picture of how the trucks are used during their life and in the transition phases, which gave an idea about usage patterns that could answer RQ2. The answer was formulated as something named phase-DNA, composed by six parameters that should change during a transition phase: Geography, Route, Driver, Traffic Condition, Assignments and Services. Through a group brainstorming with experts in connected services, ideas of which data that could be used to describe each one of the parameters in the phase-DNA were found. These were sorted and evaluated until at least one data type for each parameter was set. The specific data types were chosen because they reflected their parameter well and because they were data that were accessible in order to conduct tests and validations. The final set of data types consisted of: Route Shape, Amount of Stops, Run Time, Idle Time, Distance Driven, Coasting, Driver ID, Average Speed, Fuel Consumption and Workshop History Data. This set of data types was used for the formulation of a hypothesis, that said that after a transition phase at least some of these data types should change. This was also the point where RQ3 was answered. II The hypothesis was analysed using an exploratory analysis by plotting all the data types over time and observing if a change could be seen close to the change of ownership. The result showed that Amount of Stops and Driver ID were the most indicative data types, these two were further analysed with a statistical hypothesis test and a visualisation method. The results were used to develop an algorithm that is able to give an indication if a transition phase has occurred. The algorithm searches for changes in the six data types: Driver ID, Amount of Stops, Run Time, Distance Driven, Idle Time and Route Shape. The results from the empirical studies were used to define requirements for the development of a service based on the information of phase transition called transition alert service (TAS), which is the answer to RQ4. Furthermore possible stakeholders that could be interested in the transition phase information were investigated together with an examination of their needs. TAS fulfils the five main needs identified from the stakeholders: ease start and cancellation of services, avoid unnecessary telecom expenses, avoid that information goes to the wrong customer, find new customers and customize services. In order to solve this, an algorithm detecting a transition phase was developed; it was done by searching for changes in the six data types: Driver ID, Amount of Stops, Run Time, Distance Driven, Idle Time and Route Shape. Moreover if the TAS information is combined with other information it could be used for creating new services. Through different idea generation workshops a large number of new ideas and concepts were generated, which became the answer to RQ5. In total eleven applications for the transition alert service were developed: nine connected to change in ownership and two connected to change in utilization. Additionally, one support service named "Vehicle History" that is based on collected historical TAS was created. Further, one total solution named "No Worries Second-Hand" was created that includes five of the developed services. This total solution offers the customer the perfectly suitable second-hand truck without having to spend time searching for it. It also consists of a contract saying that if the customer signs a R&M contract, the dealer will buy back the vehicle and offer a new used vehicle when the old one gets too old or used. TAS makes this total solution possible by giving the dealer access to information about the truck and through this predict phase transitions. In conclusion, the developed services and especially the combination of them into a total solution would, according to the authors, favour the transition from a product focused company to a total solution provider, and extend the knowledge about the second-hand market.
105

Development of a low-grade energy engine with a multi-vane expander as the prime mover

Badr, O. M. January 1985 (has links)
No description available.
106

PTIP, a novel BRCT domain-containing apoptotic factor that directly promotes cytochrome c release from mitochondria to cytoplasm

Zhang, Yan 14 April 2011 (has links)
Not available / text
107

Studies on the reproductive cycle of the female cobra, Naja naja (L.)

Lance, Valentine Anthony January 1973 (has links)
published_or_final_version / Zoology / Doctoral / Doctor of Philosophy
108

Particulate organic carbon mobilisation and export from temperate forested uplands

Smith, Joanne Caroline January 2013 (has links)
No description available.
109

Tracking down Social Impacts of Products with Social Life Cycle Assessment

Ekener-Petersen, Elisabeth January 2013 (has links)
An important aspect of sustainable development is the social impacts from the consumption of goods and services. A recently developed method for social life cycle assessment (S-LCA) assesses the potential positive and negative social impacts along a product’s life cycle, while avoiding shifting negative impacts from one part of the supply chain to another. This thesis evaluated the applicability of S-LCA in three case studies, as well as a way of introducing an ethical perspective on the distribution of social impacts among stakeholders. The case study of laptop computers identified workers and the local community as the stakeholders at greatest risk of negative social impacts, with China, Russia, Saudi Arabia, Thailand and Brazil being most prone to these impacts. A case study of vehicle fuels identified some fossil and some renewable fuels with high or very high risks of negative impacts, suggesting a need for strict procurement requirements on social performance for all types of vehicle fuels. A study of e-waste recycling in Pakistan revealed negative social impacts on workers and the community, while decreasing poverty by providing employment. By performing a social hotspot assessment using S-LCA methodology, much can be learned about the potential social impacts associated with a product’s life cycle, and potentially important aspects that would otherwise have been neglected can be identified. Some methodological issues of S-LCA requiring further attention are: Indicator relevance. Impact pathways between indicators and performance assessment on social issues must be examined and improved. Aggregation and weighting of impacts and indicators. With major uncertainties still present, results must be transparent, but also aggregated for the purposes of interpretation and communication. Assessment of the use phase. To be more complete, S-LCA methodology needs to be complemented with an assessment of the use phase. Introduction of context. Identifying the context of relevant stakeholders in different parts of the life cycle would allow identification of the greatest leverage in improvement of social conditions. / En viktig del av hållbar utveckling är att hantera social påverkan från konsumtionen av varor och tjänster. Social livscykelanalys (S - LCA) är en metod som syftar till att bedöma positiv och negativ social påverkan av produkter under hela deras livscykel och samtidigt undvika att bara flytta negativ påverkan från en del av livscykeln till en annan. Denna avhandling utvärderar S - LCA i tre fallstudier, samt undersöker hur fördelningen av den sociala påverkan på olika intressentgrupper kan bedömas ur ett etiskt perspektiv. I en fallstudie som utfördes på en laptop identifierades arbetstagare och lokalsamhället som de intressenter, som löper störst risk för negativ social påverkan. Länder som Kina, Ryssland, Saudiarabien, Thailand och Brasilien var de som var mest kopplade till denna påverkan. En fallstudie kring fordonsbränslen visade att av de bränslen som bedömts uppvisade både en del fossila och en del förnybara bränslen höga eller mycket höga risker för negativ social påverkan, vilket tyder på att strikta upphandlingskrav gällande social prestanda behövs för alla typer av drivmedel. En studie av återvinning av elektroniskt avfall i Pakistan uppvisade påtaglig negativ social påverkan på arbetstagarna och lokalsamhället, samtidigt som återvinningen gav sysselsättning som minskar fattigdomen. Genom att använda S-LCA vid bedömningen av en produkt finns det mycket att lära om potentiell social påverkan från produktens livscykel. Viktiga aspekter, som annars riskerar att missas, kan nu identifieras med S-LCA. Metoden är dock inte färdigutvecklad, och metodfrågor som behöver ytterligare uppmärksamhet är: Relevanta indikatorer. Kopplingen mellan indikatorerna och den påverkan man försöker mäta måste undersökas närmare och förbättras. Sätt att aggregera och väga ihop påverkan. Med tanke på de osäkerheter som ännu så länge finns kring metoden måste resultaten hållas transparenta, samtidigt som sammanfattande resultat behövs för tolkning och kommunikation. Påverkan i användningsfasen. För att bli mer komplett, måste metoden kompletteras med en bedömning av social påverkan i användningsfasen. Sätta resultaten i sitt sammanhang. Utgångsläget för dem, som berörs av en produkts sociala påverkan avgör vilken hävstångseffekt en förbättring av de sociala förhållandena kan ha, och kan därmed påverka vilka åtgärder som bör prioriteras. / <p>QC 20131217</p>
110

Activation of the corticolimbic brain by visual food cues; Effect of menstrual cycle phase and mood

Frank, TAMAR 27 September 2009 (has links)
Hypothalamic control of food intake may be overridden by cortical and limbic brain regions that process reward and the hedonic aspect of food, affecting the ability to discriminate between homeostatic and hedonic feeding. Women, in particular may be affected since cognition and perception of reward change during the menstrual cycle. Changes in estrogen and progesterone levels during the menstrual cycle induce changes in appetite and eating behavior. Food intake declines in the peri-ovulatory period when estrogen levels peak, but increases in the luteal phase when progesterone levels increase. In this novel study we introduce a different context in which to study appetite regulation; the menstrual cycle. The two main study objectives were: 1) to compare the BOLD response between the peri-ovulatory and luteal phases of the menstrual cycle and 2) to compare the BOLD response between women in a negative and positive affect state in response to visual food stimuli using functional magnetic resonance imaging. Pictures of food, regardless of their caloric content stimulated greater activation during the follicular phase compared to the luteal phase in the orbitofrontal cortex, fusiform, amygdala and inferior operculum. Activity was present in the hippocampus, ventral tegmental area and nucleus accumbens in response to high calorie images but not low calorie images during the follicular phase. The insula showed selective activity responding to high calorie pictures in the luteal phase and low calorie pictures in the follicular phase. High calorie food cues elicited greater BOLD signal for women reporting negative affect in the putamen, amygdala, pulvinar, prefrontal cortex, pallidum, fusiform and ventral tegmental area. In summary, visual food cues produced a more robust response during the follicular phase of the menstrual cycle and during a negative mood state in brain regions modulating the rewarding and motivational effects of food images. An increased understanding of how appetite-regulating brain regions respond during the menstrual cycle and in different mood states may facilitate the development of new therapies to reduce the incidence of obesity. / Thesis (Master, Physiology) -- Queen's University, 2009-09-25 15:35:15.609

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