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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.
791

Utveckling av Verktyg för generering av Stubb- och Mockobjekt för C

Åkerström, Christian January 2008 (has links)
<p>Testdriven utveckling samt användning av enhetstestning är ett växande område. Vid användning av dessa tekniker är det önskvärt att kunna använda stubb- och mockobjekt för att ersätta en DOC(Dependent on Component).</p><p>I dagsläget finns det ett verktyg hos Enea som genererar stubbar för C++-källkod. Examensarbetet består av att vidareutveckla detta verktyg i flera avseenden. Stöd för C-kod adderas till verktyget. För C-kod adderas även möjligheten att generera stubb- och mockobjekt. Testning av verktyget görs mot ett befintligt kundprojekt hos Enea med goda resultat.</p>
792

A comparative study of job satisfaction patterns of tool makers & executives /

Tam, Yiu-cho. January 1985 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1985.
793

Development of interactive web-based tutorials for chemical engineering undergraduates

Cular, Stefan 01 June 2005 (has links)
This thesis presents the design, creation, and testing of a web-based tool for generating interactive web-based problem set assignments. In prior research (Stetka, 2001) it was shown that students enjoyed interactive problems. In this research, multiple programming languages were used to provide a web-based, fully interactive, problem solving environment for the students.Sample problem sets were written by the author and a few chemical engineering students. These web pages were then used as a basis to test the effectiveness of the web-based interactive problem sets for two engineering courses. Initial findings are presented illustrating the students results along with results of student feedback surveys. Additionally, an analysis of the feedback from the two levels of users, students and instructors are reported and some suggestions for further development are given.
794

Lärplattan i förskolan : En kvalitativ studie, med syfte att jämföra pedagogers uppfattningar med barnens verkliga användande

Israelsson, Jennie, Larsson, Johanna January 2015 (has links)
<p>Godkännandedatum: 2015-01-02</p>
795

Refactoring for Software Transactional Memory

Baum, Mark Vincent 27 February 2012 (has links)
Software transactional memory (STM) is an optimistic concurrent lock free mechanism that has the potential of positively transforming how concurrent programming is performed. STM, despite its many desirable attributes, is not yet a ubiquitous programming language feature in the commercial software domain. There are many implementation challenges with retrofitting STM into pre-existing language frameworks. Furthermore, existing software systems will also need to be refactored in order to take advantage of STM’s unique benefits. As with other time consuming and error prone refactoring processes, refactoring for STM is best done with automated tool support; it is the aim of this paper to propose such a tool. / text
796

Novel tools for engineering eukaryotic cells using a systems level approach.

Lanza, Amanda Morgan 25 August 2015 (has links)
Engineered cellular systems are a promising avenue for production of a wide range of useful products including renewable fuels, commodity and specialty chemicals, industrial enzymes, and pharmaceuticals. Achieving this breadth of biological products is facilitated by the diversity of organisms found in nature. Using biological and engineering principles, this diversity can be harnessed to make efficient and renewable bio-based products. Such advancements rely upon our ability to modify host genetics and metabolism. This work focuses on the development of new biotechnological tools which enable cellular engineering, and the implementation of these tools in eukaryotic systems. Mammalian cell engineering has important implications in protein therapeutics and gene therapy. One major limitation, however, is the ability to predictably control gene expression. We address this challenge by examining critical aspects of gene expression in human cells. First, we evaluate the impact of selection markers, a common mammalian expression element, on cell line development. In doing so, we determine that Zeocin is the best selection agent for human cells. Next, we identify loci across the genome that support high level expression of recombinant DNA and demonstrate their advantage for stable integration. Finally, we optimize a Cre recombinase based methodology that enables efficient retargeting of genomic loci. Collectively, this work augments the current genetic toolbox for human cell lines. Beyond basic gene expression, there is interest in understanding global interactions within the cell and how they relate to phenomena including gene regulation, expression and disease states. Although our tools are not yet sufficient to study these phenomena in many hosts, methods can be developed in lower eukaryotes and then adapted for more complex hosts later. We demonstrated two methods in S. cerevisiae that utilize a systems-level approach to understand complex phenotypes. First, we developed condition-specific codon optimization that utilizes systems biology information to optimize gene sequence in a condition-specific manner. Additionally, we developed a Graded Dominant Mutant Approach which can be used to dissect multifunctional proteins, understand epigenetic factors, and quantitatively determine protein-DNA interactions. Both can be implemented in many cellular hosts and expand our ability to engineer complex phenotypes in eukaryotic cell systems.
797

Vibration level characterization from a needle gun used on U.S. naval vessels

Dunn, Scott E 01 June 2006 (has links)
United States (U.S.) Navy sailors are exposed to a very large number of hazards, both chemical and physical. Occupational vibration from pneumatic air tools is one of the potential exposure hazards. There are very limited data as to the exposures to one type of tool, a needle gun or needle scaler, used by the sailors.The purpose of this study was to characterize the vibration levels generated by a needle gun used in the U.S. Navy. The design of the study evaluated the difference pressure had on the acceleration levels generated from the needle scaler. Five subjects were used in the evaluation of the tool. Each subject was required to hold the tool for twenty seconds activated without contact and activated on a surface and at two different pressures, 60 and 80 pound per square inch (psi). Each subject repeated each of the conditions three times for a total of 12 measurements. Each subject was also required to hold the tool in hand without the tool activated. The measurements were collected from an accelerometer on the needle gun following ISO 5349-1:2001 and ISO 5349-2:2001 methods. Significant differences were observed individually in pressure (p<0.0001), contact (p<0.0001)), and subjects (p<0.001). In addition, there was a significant interaction between contact and pressure (p<0.001). It was concluded that U.S. Navy sailors are not likely at significant risk to Hand-Arm Vibration Syndrome for lifetime exposures to hand transmitted vibration.
798

Orchestrating mathematical whole-class discussions in the problem-solving classroom : Theorizing challenges and support for teachers

Larsson, Maria January 2015 (has links)
Promising teaching approaches for developing students’ mathematical competencies include the approach of teaching mathematics through problem solving. Orchestrating a whole-class discussion of students’ ideas is an important aspect of teaching through problem solving. There is a wide consensus within the field that it is very challenging for the teacher to conduct class discussions that both build on student ideas and highlight key mathematical ideas and relationships. Further, fostering argumentation in the class, which is important for students’ participation, is also a grand challenge. Teachers need support in these challenges. The aim of the thesis is to characterize challenges and support for mathematics teachers in orchestrating productive problem-solving whole-class discussions that focus on both mathematical connection-making and argumentation. In particular, it is investigated how Stein et al.’s (2008) model with five practices – anticipating, monitoring, selecting, sequencing and connecting student solutions – can support teachers to handle the challenges and what constitutes the limitations of the research-based and widely-used model. This thesis builds on six papers. The papers are based on three intervention studies and on one study of a mathematics teacher proficient in conducting problem-solving class discussions. Video recordings of observed whole-class discussions as well as audio-recorded teacher interviews and teacher meetings constitute the data that are analyzed. It is concluded in the thesis that the five practices model supports teachers’ preparation before the lesson by the practice of anticipating. However, making detailed anticipations, which is shown to be both challenging and important to foster argumentation in the class, is not explicitly supported by the model. Further, the practice of monitoring supports teachers in using the variety of student solutions to highlight key mathematical ideas and connections. Challenging aspects not supported by the monitoring practice are, however, how to interact with students during their exploration to actually get a variety of different solutions as a basis for argumentation. The challenge of selecting and sequencing student solutions is supported for the purpose of connection-making, but not for the purpose of argumentation. Making mathematical connections can be facilitated by the last practice of connecting, with the help of the previous practices. However, support for distinguishing between different kinds of connections is lacking, as well as support for creating an argumentative classroom culture. Since it is a great challenge to promote argumentation among students, support is needed for this throughout the model. Lastly, despite the importance and challenge of launching a problem productively, it is not supported by the model. Based on the conclusions on challenges and support, developments to the five practices model are suggested. The thesis contributes to research on the theoretical development of tools that support teachers in the challenges of orchestrating productive problem-solving whole-class discussions.
799

A new integrated modeling approach to support management decisions of water resources systems under multiple uncertainties

Subagadis, Yohannes Hagos 08 December 2015 (has links) (PDF)
The planning and implementation of effective water resources management strategies need an assessment of multiple (physical, environmental, and socio-economic) issues, and often requires new research in which knowledge of diverse disciplines are combined in a unified methodological and operational framework. Such integrative research to link different knowledge domains faces several practical challenges. The complexities are further compounded by multiple actors frequently with conflicting interests and multiple uncertainties about the consequences of potential management decisions. This thesis aims to overcome some of these challenges, and to demonstrate how new modeling approaches can provide successful integrative water resources research. It focuses on the development of new integrated modeling approaches which allow integration of not only physical processes but also socio-economic and environmental issues and uncertainties inherent in water resources systems. To achieve this goal, two new approaches are developed in this thesis. At first, a Bayesian network (BN)-based decision support tool is developed to conceptualize hydrological and socio-economic interaction for supporting management decisions of coupled groundwater-agricultural systems. The method demonstrates the value of combining different commonly used integrated modeling approaches. Coupled component models are applied to simulate the nonlinearity and feedbacks of strongly interacting groundwater-agricultural hydrosystems. Afterwards, a BN is used to integrate the coupled component model results with empirical knowledge and stakeholder inputs. In the second part of this thesis, a fuzzy-stochastic multiple criteria decision analysis tool is developed to systematically quantify both probabilistic and fuzzy uncertainties associated with complex hydrosystems management. It integrates physical process-based models, fuzzy logic, expert involvement and stochastic simulation within a general framework. Subsequently, the proposed new approaches are applied to a water-scarce coastal arid region water management problem in northern Oman, where saltwater intrusion into a coastal aquifer due to excessive groundwater extraction for irrigated agriculture has affected the aquifer sustainability, endangering associated socio-economic conditions as well as traditional social structures. The results show the effectiveness of the proposed methods. The first method can aid in the impact assessment of alternative management interventions on sustainability of aquifer systems while accounting for economic (agriculture) and societal interests (employment in agricultural sector) in the study area. Results from the second method have provided key decision alternatives which can serve as a platform for negotiation and further exploration. In addition, this approach suits to systematically quantify both probabilistic and fuzzy uncertainties associated with the decision problem. The new approaches can be applied to address the complexities and uncertainties inherent in water resource systems to support management decisions, while serving as a platform for stakeholder participation.
800

Sustainable Arsenic Mitigation A Strategy for Scaling-up Safe Water Access : A Strategy for Scaling-up Safe Water Access

Hossain, Mohammed January 2015 (has links)
In rural Bangladesh, the drinking water supply is mostly dependent upon manually operated hand pumped tubewells, installed by the local community. The presence of natural arsenic (As) in groundwater and its wide scale occurrence has drastically reduced the safe water access across the country and put tens of millions of people under health risk. Despite significant progress in understanding the source and distribution of As and its mobilization through sediment-water interactions, there has been limited success in mitigation since the problem was discovered in the country’s water supply in 1993. This study evaluated the viability of other kinds of alternative safe drinking water options and found tubewells are the most suitable due to simplicity and technical suitability, a wide acceptance by society and above all low cost for installation, operation and maintenance. During planning and decision making in the process of tubewell installation, depth of the tubewell is a key parameter as it is related to groundwater quality and cost of installation. The shallow wells (usually &lt; 80m) are mostly at risk of As contamination. One mitigation option are deep wells drilled countrywide to depths of around 250 m. Compared to safe water demand, the number of deep wells is still very low, as the installation cost is beyond affordability of the local community, especially for the poor and disadvantaged section of the society. Using depth-specific piezometers (n=82) installed in 15 locations spread over the 410 km2 area of Matlab (an As-hot spot) in southeastern Bangladesh, groundwater monitoring was done over a 3 year period (pre- and post-monsoon for 2009-2011 period). Measurements were performed for hydrogeological characterization of shallow, intermediate deep and deep aquifer systems to determine the possibility of targeting safe aquifers at different depths as the source of a sustainable drinking water supply. In all monitoring piezometers, As was found consistently within a narrow band of oscillation probably due to seasonal effects. Hydrogeochemically, high-As shallow groundwaters derived from black sands are associated with elevated DOC, HCO3, Fe, NH4-N and PO4-P and with a relatively low concentration of Mn and SO4. Opposite to this, shallow aquifers composed of red and off-white sediments providing As-safe groundwater are associated with low DOC, HCO3, Fe, NH4-N and PO4-P and relatively higher Mn and SO4. Groundwaters sampled from intermediate deep and deep piezometers which were found to be low in As, are characterized by much lower DOC, HCO3, NH4-N and PO4-P compared to the shallow aquifers. Shallow groundwaters are mostly Ca-Mg-HCO3 type and intermediate deep and deep aquifers’ groundwaters are mostly Na-Ca-Mg-Cl-HCO3 to Na-Cl-HCO3 type. A sediment color tool was also developed on the basis of local driller’s color perception of sediments (Black, White, Off-white and Red), As concentration of tubewell waters and respective color of aquifer sediments. A total of 2240 sediment samples were collected at intervals of 1.5 m up to a depth of 100 m from all 15 nest locations. All samples were assigned with a Munsell color and code, which eventually led to identify 60 color varieties. The process continued in order to narrow the color choices to four as perceived and used by the local drillers for identification of the targeted As-safe aquifers. Munsell color codes assigned to these sediments render them distinctive from each other which reduces the risk for misinterpretation of the sediment colors. During the process of color grouping, a participatory approach was considered taking the opinions of local drillers, technicians, and geologists into account. In addition to the monitoring wells installed in the piezometer nests, results from 87 other existing drinking water supply tubewells were also considered for this study. A total of 39 wells installed in red sands at shallow depths producing As-safe water providing strong evidence that red sediments are associated with As-safe water. Average and median values were found to be less than the WHO guideline value of 10 μg/L. Observations for off-white sediments were also quite similar. Targeting off-white sands could be limited due to uncertainty of proper identification of color, specifically when day-light is a factor. Elevated Mn in red and off-white sands is a concern in the safe water issue and emphasizes the necessity of a better understanding of the health impact of Mn. White sediments in shallow aquifers are relatively uncommon and seemed to be less important for well installations. Arsenic concentrations in more than 90% of the shallow wells installed in black sands are high with an average of 239 μg/L from 66 wells installed in black sediments. It is thereby recommended that black sands in shallow aquifers must be avoided. This sediment color tool shows the potential for enhancing the ability of local tubewell drillers for the installation of As-safe shallow drinking water tubewells. Considering the long-term goal of the drinking water safety plan to provide As-safe and low-Mn drinking water supply, this study also pioneered hydrogeological exploration of the intermediate deep aquifer (IDA) through drilling up to a depth of 120 m. Clusters of tubewells installed through site optimization around the monitoring piezometer showed a similar hydrochemical buffer and proved IDA as a potential source for As-safe and low-Mn groundwater. Bangladesh drinking water standard for As (50 µg/L) was exceeded in only 3 wells (1%) and 240 wells (99%) were found to be safe. More than 91% (n=222) of the wells were found to comply with the WHO guideline value of 10 µg/L. For Mn, 89% (n=217) of the wells show the concentration within or below the previous WHO guideline value of 0.4 mg/L, with a mean and median value of 0.18 and 0.07 mg/L respectively. The aquifer explored in the Matlab area shows a clear pattern of low As and low Mn. The availability of similar sand aquifers elsewhere at this depth range could be a new horizon for tapping safe drinking water at about half the cost of deep tubewell installation. All findings made this study a comprehensive approach and strategy for replication towards As mitigation and scaling-up safe water access in other areas of Bangladesh and elsewhere having a similar hydrogeological environment. / <p>QC 20151211</p> / Sida-SASMIT project (Sida Contribution 75000854).

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