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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.
441

Multiscale fractality with application and statistical modeling and estimation for computer experiment of nano-particle fabrication

Woo, Hin Kyeol 24 August 2012 (has links)
The first chapter proposes multifractal analysis to measure inhomogeneity of regularity of 1H-NMR spectrum using wavelet-based multifractal tools. The geometric summaries of multifractal spectrum are informative summaries, and as such employed to discriminate 1H-NMR spectra associated with different treatments. The methodology is applied to evaluate the effect of sulfur amino acids. The second part of this thesis provides essential materials for understanding engineering background of a nano-particle fabrication process. The third chapter introduces a constrained random effect model. Since there are certain combinations of process variables resulting to unproductive process outcomes, a logistic model is used to characterize such a process behavior. For the cases with productive outcomes a normal regression serves the second part of the model. Additionally, random-effects are included in both logistics and normal regression models to describe the potential spatial correlation among data. This chapter researches a way to approximate the likelihood function and to find estimates for maximizing the approximated likelihood. The last chapter presents a method to decide the sample size under multi-layer system. The multi-layer is a series of layers, which become smaller and smaller. Our focus is to decide the sample size in each layer. The sample size decision has several objectives, and the most important purpose is the sample size should be enough to give a right direction to the next layer. Specifically, the bottom layer, which is the smallest neighborhood around the optimum, should meet the tolerance requirement. Performing the hypothesis test of whether the next layer includes the optimum gives the required sample size.
442

Advanced Traffic Service / Avancerad Trafiktjänst

Löfås, Peter January 2005 (has links)
More and more travellers use navigation-aid software to find the way while driving. Most of todays systems use static maps with little or no information at all about currently yeilding roads conditions and disturbances in the network. It is desirable for such services in the future to include information about road works, accidents, surface conditions and other types of events that affects what route is currently the best. It is also desirable to notify users about changes in the prerequisites of the chosen route after they have started their trip. This thesis investigates methods to include dynamic traffic information in route calculations and notifying users when the characteristics change for their chosen route. The thesis utilizes dynamic traffic information from The Swedish Road Agencys (Vägverket) central database for traffic information, TRISS and calculates affected clients with help of positioning through the GSM network.
443

The Development Of A Building Energy Performance Evaluation Program (enad) For Architectural Design Process

Cakici, Fatma Zehra 01 January 2013 (has links) (PDF)
Energy performance in buildings has become one of the most broadly debated subjects in contemporary architecture / and current legislation has emphasized its importance by requiring buildings to possess an energy performance certificate. Due to the technological advances in computational tools, it is possible to analyze the energy performance of buildings before construction starts / however most energy performance evaluation tools, requiring complex solid models and high technical knowledge in the field, can be used only during the post design phases. Since any design decision has an important effect on the energy performance of a building, evaluation tools should be used from the very beginning of the design process. In this dissertation, a building energy performance evaluation program, entitled the Energy performance Advisor (EnAd), was developed for evaluating the energy performance of buildings considering not only the legal framework of Turkey, but also the building design process. The program does not need advanced expertise, and was developed to be usable in any phase of the design process. The program, using the monthly calculation method of TS EN ISO 13790, was developed based on the European Union Directive on Energy Performance in Buildings (EPBD) and the current Turkish legislation on the subject. EnAd integrates the legal framework with the energy performance criterion into the building design process, while providing rapid feedback on energy performance and related legislation, and guiding the designer to improve design decisions. This dissertation has also shown the effects of building size, exposed surfaces, ventilation and infiltration, window-wall ratio, U-values, set-point temperatures and temperature differences between the outside and inside spaces on energy performance of buildings through generic case studies while searching the reasons for discrepancies between the results derived from the four evaluation tools, three of which is highly acknowledged energy performance evaluation tools. The validity, reliability, precision and usability of EnAd as a design-support tool has been proved through the usability and convergence tests conducted. Finally, the thesis has pointed out the importance of the use of energy performance evaluation tools from early stages of architectural design process to achieve higher performances as well as the roles of decision makers in this process.
444

Absorbed dose and biological effect in light ion therapy

Hollmark, Malin January 2008 (has links)
Radiation therapy with light ions improves treatment outcome for a number of tumor types. The advantageous dose distributions of light ion beams en-able exceptional target conformity, which assures high dose delivery to the tumor while minimizing the dose to surrounding normal tissues. The demand of high target conformity necessitates development of accurate methods to calculate absorbed dose distributions. This is especially important for heavy charged particle irradiation, where the patient is exposed to a complex radia-tion field of primary and secondary ions. The presented approach combines accurate Monte Carlo calculations using the SHIELD-HIT07 code with a fast analytical pencil beam model, to pro-vide dose distributions of light ions. The developed model allows for ana-lytical descriptions of multiple scattering and energy loss straggling proc-esses of both primary ions and fragments, transported in tissue equivalent media. By applied parameterization of the radial spread of fragments, im-proved description of radial dose distributions at every depth is obtained. The model provides a fast and accurate tool of practical value in clinical work. Compared to conventional radiation modalities, an enhanced tissue response is seen after light ion irradiation and biological optimization calls for accu-rate model description and prediction of the biological effects of ion expo-sure. In a joint study, the performance of some radiobiological models is compared for facilitating the development towards more robust and precise models. Specifically, cell survival after exposure to various ion species is modeled by a fast analytical cellular track structure approach in conjunction with a simple track-segment model of ion beam transport. Although the stud-ies show that descriptions of complex biological effects of ion beams, as given by simple radiobiological models, are approximate, the models may yet be useful in analyzing clinical results and designing new strategies for ion therapy.
445

Besparingsmodell för produktivitetshöjande arbete inom skärande bearbetningsteknik

Jonsson, Linda-Maria January 2013 (has links)
The market is developing and a growing competition increases pressure on companies to maintain their competitive advantage. Working with cost savings is a way to enhance earnings in a short term but also in a longer perspective. Volvo Powertrain Production Köping has an overall goal; to reduce costs by nine percentages in three years. To achieve the goal, Volvo Powertrain Production Köping works with World Class Manufacturing where the Department of Processing Technology constitutes an important part. Volvo Powertrain Production Köping lacks a standard for how savings within the metal cutting tool area are to be calculated. This makes it difficult to control and monitor their business outcome but it also causes difficulties in controlling the tool suppliers’ outcome. The suppliers’ outcome is later used as the basis in price negotiations which means that Volvo Powertrain Production Köping lacks information that can improve their outcome of a negotiation. The aim of the project is to increase understanding of how activities of processing technology affect productivity through a spreadsheet model. Starting with a current status report and a literature review revealed that many companies are missing an hourly rate designed at machine level. There are theories saying that the machine hourly rate should be allocated for both producing state and downtime, which in subsequent interviews with other companies proves to be far from being reality. Collected information was analyzed and a model was developed. The model has been tested in two improvement projects and the outcome has been compared with existing calculations from tool vendors. The result of the thesis is a standardized savings model with a machine specific hourly rate, taking into account both producing and downtime states. The savings model is based on the currently used Cost Deployment system. The proposed spreadsheet will monitor the outcome of tool suppliers which will result in a better control of cost savings and price negotiations. The savings model is not solely for savings calculations; the model also helps the user to understand how different parameters affect the cost of manufacturing. The expectation is to increase cost awareness and reduce the risk of sub-optimization in Volvo Powertrain Production Köping´s operations. The developed hourly rate is not specific to processing technology but the entire company can benefit from the spreadsheet. From a wider viewpoint, the model is applicable to manufacturing companies that have a detailed loss monitoring system similar to Cost Deployment. / Marknaden utvecklas och konkurrensen ökar vilket medför ett ökat tryck på företagen att behålla sin konkurrensfördel. Att arbeta med kostnadsbesparingar är det säkraste sättet för att öka förtjänsten på kort sikt men även i ett längre perspektiv. Volvo Powertrain Production Köping har ett övergripande mål som innebär att kostnaderna ska reduceras med nio procent på tre år. För att uppnå målet arbetar Volvo Powertrain Production Köping med World Class Manufacturing där bearbetningsteknik utgör en viktig del. Volvo Powertrain Production Köping saknar en standard för hur besparingar inom bearbetningsteknik ska beräknas. Detta medför svårigheter att kontrollera och följa upp den egna verksamhetens utfall men också svårigheter att kontrollera verktygsleverantörernas utfall som ligger till grund för inköpsförhandlingar. Syftet med examensarbetet är att öka förståelsen för hur aktiviteter inom det bearbetningstekniska området påverkar produktiviteten genom en kalkylmodell. Arbetet började med en nulägesbeskrivning och en litteraturgenomgång som visade att många företag saknade en timkostnad framtagen på maskinnivå. Det finns teori som säger att maskintimkostnaden bör finnas både för producerande tillstånd och stillestånd vilket i efterföljande kvalitativa intervjuer med andra företag visar sig vara långt ifrån verkligheten. Insamlad information analyserades och en modell utvecklades. Modellen har testats i två förbättringsprojekt och utfallet har jämförts med befintliga kalkyler från verktygsförsäljare. Resultatet av examensarbetet är en standardiserad besparingskalkyl med en maskinspecifik timkostnad där hänsyn tas till om maskinen producerar eller om maskinen har oplanerat stillestånd. Besparingskalkylen är baserad på Cost Deployment som redan används inom Volvo Powertrain Production Köping. Besparingsmodellen är inte enbart till för att beräkna besparingar utan modellen kan också hjälpa användaren att förstå hur olika parametrar påverkar tillverkningskostnaden i hopp om att öka kostnadsmedvetenheten och minska risken för suboptimering i den egna verksamheten. Den framtagna timkostnaden är inte specifik för bearbetningsteknik utan hela företaget har nytta av kalkylen vid besparingsberäkningar. I ett större perspektiv är modellen applicerbar på tillverkningsföretag som har en noggrann förlustuppföljning liknande Cost Deployment.
446

Impact of Geometric Uncertainties on Dose Calculations for Intensity Modulated Radiation Therapy of Prostate Cancer

Jiang, Runqing January 2007 (has links)
IMRT uses non-uniform beam intensities within a radiation field to provide patient-specific dose shaping, resulting in a dose distribution that conforms tightly to the planning target volume (PTV). Unavoidable geometric uncertainty arising from patient repositioning and internal organ motion can lead to lower conformality index (CI), a decrease in tumor control probability (TCP) and an increase in normal tissue complication probability (NTCP). The CI of the IMRT plan depends heavily on steep dose gradients between the PTV and organ at risk (OAR). Geometric uncertainties reduce the planned dose gradients and result in a less steep or “blurred” dose gradient. The blurred dose gradients can be maximized by constraining the dose objective function in the static IMRT plan or by reducing geometric uncertainty during treatment with corrective verification imaging. Internal organ motion and setup error were evaluated simultaneously for 118 individual patients with implanted fiducials and MV electronic portal imaging (EPI). The Gaussian PDF is patient specific and group standard deviation (SD) should not be used for accurate treatment planning for individual patients. Frequent verification imaging should be employed in situations where geometric uncertainties are expected. The dose distribution including geometric uncertainties was determined from integration of the convolution of the static dose gradient with the PDF. Local maximum dose gradient (LMDG) was determined via optimization of dose objective function by manually adjusting DVH control points or selecting beam numbers and directions during IMRT treatment planning. EUDf is a useful QA parameter for interpreting the biological impact of geometric uncertainties on the static dose distribution. The EUDf has been used as the basis for the time-course NTCP evaluation in the thesis. Relative NTCP values are useful for comparative QA checking by normalizing known complications (e.g. reported in the RTOG studies) to specific DVH control points. For prostate cancer patients, rectal complications were evaluated from specific RTOG clinical trials and detailed evaluation of the treatment techniques. Treatment plans that did not meet DVH constraints represented additional complication risk. Geometric uncertainties improved or worsened rectal NTCP depending on individual internal organ motion within patient.
447

Impact of Geometric Uncertainties on Dose Calculations for Intensity Modulated Radiation Therapy of Prostate Cancer

Jiang, Runqing January 2007 (has links)
IMRT uses non-uniform beam intensities within a radiation field to provide patient-specific dose shaping, resulting in a dose distribution that conforms tightly to the planning target volume (PTV). Unavoidable geometric uncertainty arising from patient repositioning and internal organ motion can lead to lower conformality index (CI), a decrease in tumor control probability (TCP) and an increase in normal tissue complication probability (NTCP). The CI of the IMRT plan depends heavily on steep dose gradients between the PTV and organ at risk (OAR). Geometric uncertainties reduce the planned dose gradients and result in a less steep or “blurred” dose gradient. The blurred dose gradients can be maximized by constraining the dose objective function in the static IMRT plan or by reducing geometric uncertainty during treatment with corrective verification imaging. Internal organ motion and setup error were evaluated simultaneously for 118 individual patients with implanted fiducials and MV electronic portal imaging (EPI). The Gaussian PDF is patient specific and group standard deviation (SD) should not be used for accurate treatment planning for individual patients. Frequent verification imaging should be employed in situations where geometric uncertainties are expected. The dose distribution including geometric uncertainties was determined from integration of the convolution of the static dose gradient with the PDF. Local maximum dose gradient (LMDG) was determined via optimization of dose objective function by manually adjusting DVH control points or selecting beam numbers and directions during IMRT treatment planning. EUDf is a useful QA parameter for interpreting the biological impact of geometric uncertainties on the static dose distribution. The EUDf has been used as the basis for the time-course NTCP evaluation in the thesis. Relative NTCP values are useful for comparative QA checking by normalizing known complications (e.g. reported in the RTOG studies) to specific DVH control points. For prostate cancer patients, rectal complications were evaluated from specific RTOG clinical trials and detailed evaluation of the treatment techniques. Treatment plans that did not meet DVH constraints represented additional complication risk. Geometric uncertainties improved or worsened rectal NTCP depending on individual internal organ motion within patient.
448

Interaction of Nanosecond and Femtosecond Laser Pulses with Carbon: Deposition of Carbon Films having Novel Compositions

Hu, Anming 16 May 2008 (has links)
A comparison of the composition and structure of carbon films deposited by ns and fs laser ablation of graphite is the subject of this thesis. In addition, the effect of irradiation on the surface of graphite has been investigated in detail. Laser-induced phase transitions from graphite to sp-bonded carbon and trans-polyacetylene chains as well as the formation of nano-diamond have been observed after irradiation with fs pulses. An optical orientation mechanism involving both electric and magnetic interactions is proposed to understand the formation of nano-stripes and other structures on irradiated graphite surfaces. These phenomena are not observed after nanosecond laser irradiation. Tetrahedral carbon (ta-C) films deposited at cryogenic temperatures using ns laser radiation consist of sub-micron graphitized grains embedded in a matrix of sp3-hybridized bonded carbon. Nano-buckling is evident in ta-C films deposited by fs ablation where the composition is found to consist of mixed sp, sp2, and sp3 – hybridized carbons species. It is found that the concentration of sp-bonded chains is negligible in ns-C films. Surface enhanced Raman spectroscopy has been used to characterize molecular species in ns and fs carbon films. Time of flight mass spectroscopy has been used to study plume species produced by laser ablation. It is also found that polyyne molecules can be formed by fs laser dissociation of small molecules in organic solvents. This process is accompanied by the deposition of hexagonal nano-diamond films on substrates placed near the laser focus during irradiation. This opens a new path in the synthesis of 1D conducting molecules and nano-diamond materials for nano-science applications. Quantum chemical calculations involving density functional theory (Gaussian '03) have been carried out in support of this work and have been used to study Raman and IR vibrational modes of several novel carbon molecules synthesized in ta-C films and in the liquid phase. These studies have been extended to assist in the identification of astronomical spectra.
449

Uppföljning av nyckeltal för större bro- och betongtunnelentreprenader :   Nyckeltal tänkta att användas för att kvalitetssäkra anbudsarbete

Due-Boje, Anna January 2009 (has links)
Uppdragsgivare för detta examensarbete är Skanska Sverige AB Region Stora Projekt, som arbetar med stora bro- och anläggningsprojekt. Störst behov ligger i att få ökad kunskap om de Allmännai projekten. Arbetet med anbudskalkyler innebär att förutse projektkostnader och kostnaderna Allmänna kostnader utgör en betydande del av projektets totalkostnad och är svårkalkylerade. Generellt uttryckt utgör denna post de byggkostnader som används gemensamt i projektet. Nyckeltal komprimerar information i syfte att göra den mer lättillgänglig för användaren. Syftet med denna rapport är att få fram nyckeltal tänkta att i första hand användas till att kvalitetssäkra kommande anbudsarbeten. Det material och data som rapporten baseras på är intern information om referensprojekten och slutrapporter. För två av resurserna kan nyckeltal presenteras, samma gäller för en tredje baserat på att referensprojekten har liknande utförande. Det är rimligt för en fjärde. De resterande är för objektsspecifika och det finns för lite underliggande data för att kunna dra någon slutsats. För dessa krävs det fler referensprojekt för att kunna få fram tillförlitlig data. / The taskmaster for this thesis is Skanska Sverige AB Region Stora Projekt, who works with large bridge- and construction projects. Greatest need is to enhance the understanding of the General costs of the projects. Tender calculation means to predict project costs and General costs are a significant part of the project's total cost and is difficult to calculate. This post is, broadly expressed, the construction costs that are used jointly in the project. Ratios compress information in order to make it more accessible to the user. The purpose of this report is to present ratios primarily intended to be used to quality-assure future tender work. The material and data to which the report is based on is internal information about the reference projects and their final reports. For two of the resources ratios can be presented, the same applies to a third based on that the reference projects have similar design. It is reasonable for a fourth. The remainder is too object-specific and there is little underlying data to draw any conclusions. For these require more reference projects in order to obtain reliable data.
450

Projektering av platsbyggd villa / Planning of placebuild detached house

Al Jaafar, Jaafar January 2008 (has links)
Abstract (in English) "This thesis work is a design project of an on-site construcktions. The issue addressed by the project was how to devise and design an detached house I have examined which architecture-drawings, construcktion-drawings and static calculations are needed to produce an on-site construcktions detached house. The result is presented in the finished drawings for the construction documents, which show a one-storey detached house with an attractive/accessible construction plan. It uses the combination of a strong style of architecture and a clear influence of functional design. This is clarified by the bench ceilings, and the facade, which is partly laying panel, partly white trimmed. Size: 153 square meters Number of rooms: 6, where of 3 are bedrooms." / Sammanfattning Detta examensarbete är ett utformningsprojekt av en platsbyggd villa. Frågeställningen till projektet var hur man kan utforma en villa. Jag har undersökt vilka A-ritningar, K-ritningar samt statiska beräkningar som behövs för att producera en platsbyggd villa. Resultatet visar färdiga ritningar till bygghandlingar vilket betyder enplans villa med attraktiv/öppen planlösning och en stark byggnadsstil med tydliga inflytanden av funkisstil. Detta tydliggörs genom pulpettaken, och fasaden som är delvis liggande panel, delvis vit putsad. Yta: 153 kvm Antal rum: 6, varav sovrum: 3

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