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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.
361

Breaking the silos: Bridging the resource nexus in the textile industry when adapting to Zero Liquid Discharge

Dahlgren, Maja January 2016 (has links)
The concept of resource nexus is an acknowledgement of the interconnections between the uses of natural resources. This research will further the work done on the resource nexus by examining the multiple effects of measures taken in the Indian textile industry to lower the costs incurred due to the implementation of Zero Liquid Discharge (ZLD). ZLD combines a variety of technologies to cease the discharge of untreated water from production processes to the surrounding area. The paper will, based on surveys answered by an IKEA supplier and four of IKEA’s sub-suppliers of textile in India, present a multiple case study of possible multiple effects of projects undertaken to lower the increased cost of manufacturing with ZLD. Building on the multiple case study, and marrying it with the knowledge of the multiple benefits of energy efficiency improvements, the Value Added Water (VAW) tool, and the rebound effect, this paper constructs and offers a Multiple Effects Framework (MEF) for measures taken in factories as a response to the increased cost of manufacturing with ZLD. The framework handles both quantifiable and non-quantifiable multiple effects of measures taken, such as changes in resource use (water, energy, chemicals, materials), productivity and work environment. The MEF aggregates a more comprehensive picture of the overall effects of measures taken to adapt to the increased costs associated with ZLD in the textile supply chain, and can to a certain extent be applied to other factories facing a future mandate for ZLD. When changed accordingly, the framework can also be applied to other situations and industries as a decision-making and evaluation tool. In order to deepen the understanding of customer expectations and future trends, interviews were made with IKEA co-workers and a consultant involved with the factories investigated. Lessons learnt by IKEA and the consultant regarding ZLD implementation and the resource nexus are presented for internalization by factories, customers and authorities.
362

The deterrence effect of the implementation of the Department of Defense's drug prevention policy among military personnel

Meletiadis, Ananias 03 1900 (has links)
Approved for public release, distribution is unlimited / This thesis examines the magnitude of the deterrence effect associated with the implementation of the "zero tolerance" policy in the U.S. military in the early 1980s. The estimation of the deterrence effect is based on the estimation of linear probability models (LPM). A difference-in-difference estimator is obtained by comparing pre- and post-policy differences in drug use rates in the military and civilian sectors. The thesis uses data on drug participation drawn from the National Household Survey of Drug Abuse and the DoD Worldwide Health Survey. The study investigates the deterrence effect for the military as a whole, for each branch, for various age groups, and two different measures of drug participation. The results show that a significant deterrence effect appears to have been associated with the implementation of the "zero tolerance" and drug testing policy, especially for the past year drug participation rates. Additionally, there is evidence that individuals above 25 years old who are more educated and married have smaller drug participation rates than the rest of the population. / Lieutenant Commander, Hellenic Navy
363

Framtidens krav på byggnaders klimatskal : – En utredning åt Sigma Civil AB

Garzon Gamboa, Alirio January 2016 (has links)
Samtidigt som kraven på energieffektivitet inom byggbranschen blir allt hårdare har klimatskalets utformning stor betydelse. Författarens uppgift är att utreda åt Sigma Civil AB hur ett verktyg som beräknar U-värden utformas samt att med hjälp av den göra en jämförande studie på yttertak och ytterväggar, med avseende på klimatskalets påfrestningar.   Andra delar som ingår i klimatskalet är grundkonstruktioner men eftersom det är ett arbete som omfattar 10 veckor avgränsas arbetet till yttertak och ytterväggar. För att arbetet skulle kunna utföras på ett bra sätt som möjligt har författaren genom litteraturstudier i form av böcker, internetbaserade sidor och olika rapporter tagit del av information som hjälpt både vid utförande av beräkningsverktyget men också vid jämförelsen av byggdelar.   Resultatet för den här studien visade att koljerntekniken på grund av sin täta struktur fungerar bäst av de takkonstruktioner som jämfördes i studien. I den analys som gjordes för väggkonstruktioner var det en yttervägg med PIR-isolering som klarade sig bäst. En av de slutsatser som jag drar av studien är att bättre isoleringsmaterial krävs för att klara framtidens krav på klimatskalet. Det andra som är viktigt att ta med sig från studien är att byggbranschen bör vara öppen för nya tekniker, som till exempel koljerntekniken och PIR-isoleringen. / While requirements increasingly become harder in the construction industry that it will be built energy efficient, buildings envelope design plays a very large part. My task is to investigate for Sigma Civil AB how a tool that calculates the U-value is formed as well as using it to make a comparative study on the roof and exterior wall, with respect for the building envelope external influences.   Another part of the building envelope is the basic designs, but because it is a work where is only 10 weeks I need to delimit to the roof and exterior walls. In order that the work could be carried out in the best possible way I did literature study in form of books, internet based pages and various reports to receive information that helped me both when I was performing the calculation tool but also doing the comparison of the building parts.   The result of this study showed that the koljern-technique because of its dense structure works best as a roof, compared to the other roofs in the study. In the analysis made for wall constructions, it was an exterior wall with PIR-insulation that worked best. One of the conclusions that I draw from this study is that better insulation needs to meet future requirements for the building envelope. The other thing that is important to take from the study is that the construction industry should be open to new technologies, such as the koljern-technique and PIR-insulation.
364

Studie av lågenergibyggnader inför projektering av nära-nollenergi förskolor / Study of low energy buildings in preparation of near zero energy preschool projects

Nilsson, Daniel, Hallberg, Vilhelm January 2016 (has links)
Purpose: Production and utilization of buildings contributes immensely to global carbon dioxide emissions. The construction sector today accounts for over a third of global energy use will increase as the world population increases. According to the EU Directive from 2010, all new buildings in EU member countries as of December 31, 2020 are to be classified as near-zero energy buildings (NZEB). The goal is to investigate the various energy-affecting measures of the involved architects, structural engineers and planners that can improve the energy performance of a kindergarten to be closer to near-zero and identify obstacles that make it more difficult to achieve NZEB. Method: The investigation strategies for the project are qualitative methods in the form of semi-structured interviews with architects, planners and ventilation engineers for six different kindergartens. The interviews were conducted by telephone in which the questions were sent in advance to those interviewed. Mail interviews were conducted early on which resulted in either short answers or not answers at all. The energy performance documents of the different kindergartens were analyzed to get information about the different energy performances. Findings: The result does not contain a solution as to what the near-zero energy definition is or how to define it, but is more like guidance concerning what factors you can influence to get closer to near-zero energy for a kindergarten. Recurring problems surfacing in the interviews is that not all the involved roles have been able to influence predetermined choices of shape and space that, among other things, contribute to a limited space for services that planners are having difficulty influencing afterwards. Implications: The result helps contribute to making sure buildings are built in a more energy-efficient way and by such reducing the construction sector's share of the global energy consumption. The building's energy efficiency may not contribute to poor indoor climate in such a way that it affects children's health in a negative manner. This results in a need for careful planning where all parties can contribute with their best energy efficiency solutions without being too limited by the architectural constraints of shape and space. Alternatively, better communication between planners and architects in the earlier stages. Good planning contributes to a better result. Limitations: The result is based on Swedish kindergartens in a Nordic climate and should not be applied in countries without a Nordic climate. The result is not only applicable to kindergartens but is largely applicable to most similar buildings. Contact with more architects, constructional engineers, planners and more kindergartens would have given a better result.
365

Bayesian modelling of recurrent pipe failures in urban water systems using non-homogeneous Poisson processes with latent structure

Economou, Theodoros January 2010 (has links)
Recurrent events are very common in a wide range of scientific disciplines. The majority of statistical models developed to characterise recurrent events are derived from either reliability theory or survival analysis. This thesis concentrates on applications that arise from reliability, which in general involve the study about components or devices where the recurring event is failure. Specifically, interest lies in repairable components that experience a number of failures during their lifetime. The goal is to develop statistical models in order to gain a good understanding about the driving force behind the failures. A particular counting process is adopted, the non-homogenous Poisson process (NHPP), where the rate of occurrence (failure rate) depends on time. The primary application considered in the thesis is the prediction of underground water pipe bursts although the methods described have more general scope. First, a Bayesian mixed effects NHPP model is developed and applied to a network of water pipes using MCMC. The model is then extended to a mixture of NHPPs. Further, a special mixture case, the zero-inflated NHPP model is developed to cope with data involving a large number of pipes that have never failed. The zero-inflated model is applied to the same pipe network. Quite often, data involving recurrent failures over time, are aggregated where for instance the times of failures are unknown and only the total number of failures are available. Aggregated versions of the NHPP model and its zero-inflated version are developed to accommodate aggregated data and these are applied to the aggregated version of the earlier data set. Complex devices in random environments often exhibit what may be termed as state changes in their behaviour. These state changes may be caused by unobserved and possibly non-stationary processes such as severe weather changes. A hidden semi-Markov NHPP model is formulated, which is a NHPP process modulated by an unobserved semi-Markov process. An algorithm is developed to evaluate the likelihood of this model and a Metropolis-Hastings sampler is constructed for parameter estimation. Simulation studies are performed to test implementation and finally an illustrative application of the model is presented. The thesis concludes with a general discussion and a list of possible generalisations and extensions as well as possible applications other than the ones considered.
366

Zero-shot Learning for Visual Recognition Problems

Naha, Shujon January 2016 (has links)
In this thesis we discuss different aspects of zero-shot learning and propose solutions for three challenging visual recognition problems: 1) unknown object recognition from images 2) novel action recognition from videos and 3) unseen object segmentation. In all of these three problems, we have two different sets of classes, the “known classes”, which are used in the training phase and the “unknown classes” for which there is no training instance. Our proposed approach exploits the available semantic relationships between known and unknown object classes and use them to transfer the appearance models from known object classes to unknown object classes to recognize unknown objects. We also propose an approach to recognize novel actions from videos by learning a joint model that links videos and text. Finally, we present a ranking based approach for zero-shot object segmentation. We represent each unknown object class as a semantic ranking of all the known classes and use this semantic relationship to extend the segmentation model of known classes to segment unknown class objects. / October 2016
367

Surface Charge Characterization of Anatase and Rutile using Flow Adsorption Microcalorimetry

Hawkins, Tyler 14 December 2016 (has links)
Titanium dioxide (TiO2) attracts extensive attention due to its widespread technological and environmental applications. This study seeks to investigate the surface charging behavior of the two TiO2 polymorphs, anatase and rutile, using Flow Adsorption Microcalorimetry (FAMC). FAMC allows direct quantitative measurement of the heat of a surface reaction; these calorimetric heats are directly proportional to the surface charge. Determining the magnitude of positive and negative charges at the surface over a range of pHs allows for the determination of the point of zero net charge (PZNC) via a unique calorimetric method that removes many of the shortcomings related to the other analytical techniques used for such measurements.
368

Investigations on Energy Efficient Buildings : - the aim to reach zero energy buildings

Chee, John January 2017 (has links)
The European Parliament Buildings Directive (EPBD) obliges Sweden to develop plans to enhance the amount of NZEB. Define what NZEB for them exactly constitutes - technical definitions and system boundaries for energy performance calculations. The National Board of Housing, Building and Planning in Sweden has received an assignment from the Swedish government to propose the definition and quantitative approach on energy requirements for NZEB. NBHBP suggest the system boundary should be the delivered (bought) energy. The delivered energy divide into two different energy form. The set system boundary to calculate the specific energy performance with the introduced weighted factor. Makes it possible to compensate the specific energy performance by using renewable energy generators on site. The risk is inefficient buildings can use renewable energy technologies on site to compensate the delivered energy to achieve the 80 kWh/m2, year (the proposed energy requirements for NZEB). This results to high energy cost along with large investments in renewable technologies on site, or the need to add fossil fuels to make up the high-energy demand. The both reference houses Circuitus and Bright Living are NZEB, per the Swedish definition proposal of NZEB from NBHBP. The most significant difference is Circuitus has better heat exchanger and building envelope than Bright Living.
369

A Drift Eliminated Attitude & Position Estimation Algorithm In 3D

Zhi, Ruoyu 01 January 2016 (has links)
Inertial wearable sensors constitute a booming industry. They are self contained, low powered and highly miniaturized. They allow for remote or self monitoring of health-related parameters. When used to obtain 3-D position, velocity and orientation information, research has shown that it is possible to draw conclusion about issues such as fall risk, Parkinson disease and gait assessment. A key issues in extracting information from accelerometers and gyroscopes is the fusion of their noisy data to allow accurate assessment of the disease. This, so far, is an unsolved problem. Typically, a Kalman filter or its nonlinear, non-Gaussian version are implemented for estimating attitude â?? which in turn is critical for position estimation. However, sampling rates and large state vectors required make them unacceptable for the limited-capacity batteries of low-cost wearable sensors. The low-computation cost complementary filter has recently been re-emerging as the algorithm for attitude estimation. We employ it with a heuristic drift elimination method that is shown to remove, almost entirely, the drift caused by the gyroscope and hence generate a fairly accurate attitude and drift-eliminated position estimate. Inertial sensor data is obtained from the 10-axis SP-10C sensor, attached to a wearable insole that is inserted in the shoe. Data is obtained from walking in a structured indoor environment in Votey Hall.
370

Zero Divisors among Digraphs

Smith, Heather Christina 19 April 2010 (has links)
This thesis generalizes to digraphs certain recent results about graphs. There are special digraphs C such that AxC is isomorphic to BxC for some pair of distinct digraphs A and B. Lovasz named these digraphs C zero-divisors and completely characterized their structure. Knowing that all directed cycles are zero-divisors, we focus on the following problem: Given any directed cycle D and any digraph A, enumerate all digraphs B such that AxD is isomorphic to BxD. From our result for cycles, we generalize to an arbitrary zero-divisor C, developing upper and lower bounds for the collection of digraphs B satisfying AxC isomorphic to BxC.

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