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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.
51

Den självförgörande kampen : En existentiell studie om självdestruktivitet

Nilsson, Maria January 2006 (has links)
<p>De flesta människor som är självdestruktiva i vårt samhälle får en diagnos ställd som understryker att de på ett eller annat vis är psykiskt sjuka, den vanligaste diagnosen är Borderline Personlighetsstörning. I denna studie ifrågasätts detta psykopatologiska perspektiv och istället ämnar jag undersöka om det går att bredda begreppet självdestruktivitet genom att använda ett existentiellt perspektiv. I grunden för studien återfinns teorier från Kierkegaard, May och Fromm vilka berör begrepp som ångest och frihet, två nyckelbegrepp i denna studie. Materialet är insamlat via intervjuer. Genom att använda hermeneutik som analysmetod har uppsatsförfattaren haft möjlighet att använda sin förförståelse i ämnet och via den hermeneutiska cirkeln tolkas materialet. Resultatet speglar de självdestruktivas inre upplevelser av kampen mot ångesten. De söker en identitet men låg självkänsla och tron att de behöver de destruktiva handlingarna för att överleva slår ständigt undan benen för dem. Att ha utgångspunkten i existentialism bidrar till att människan och hennes existentiella frågor får stå i fokus. Genom att ha tilltro till människors egen förmåga att ta sig ur sin problematik skapas en alternativ behandling. Istället för att, som i det psykopatologiska perspektivet, ställa en determinerande diagnos på människan kan man i det existentiella perspektivet lägga mer ansvar på människan och utveckla henne genom att våga se det friska och sunda.</p>
52

Den självförgörande kampen : En existentiell studie om självdestruktivitet

Nilsson, Maria January 2006 (has links)
De flesta människor som är självdestruktiva i vårt samhälle får en diagnos ställd som understryker att de på ett eller annat vis är psykiskt sjuka, den vanligaste diagnosen är Borderline Personlighetsstörning. I denna studie ifrågasätts detta psykopatologiska perspektiv och istället ämnar jag undersöka om det går att bredda begreppet självdestruktivitet genom att använda ett existentiellt perspektiv. I grunden för studien återfinns teorier från Kierkegaard, May och Fromm vilka berör begrepp som ångest och frihet, två nyckelbegrepp i denna studie. Materialet är insamlat via intervjuer. Genom att använda hermeneutik som analysmetod har uppsatsförfattaren haft möjlighet att använda sin förförståelse i ämnet och via den hermeneutiska cirkeln tolkas materialet. Resultatet speglar de självdestruktivas inre upplevelser av kampen mot ångesten. De söker en identitet men låg självkänsla och tron att de behöver de destruktiva handlingarna för att överleva slår ständigt undan benen för dem. Att ha utgångspunkten i existentialism bidrar till att människan och hennes existentiella frågor får stå i fokus. Genom att ha tilltro till människors egen förmåga att ta sig ur sin problematik skapas en alternativ behandling. Istället för att, som i det psykopatologiska perspektivet, ställa en determinerande diagnos på människan kan man i det existentiella perspektivet lägga mer ansvar på människan och utveckla henne genom att våga se det friska och sunda.
53

Feasibility Study of a Portable Coupled 3He Detector with LaBr3 Gamma Scintillator for Field Identification and Quantification of Nuclear Material

Strohmeyer, Daniel C. 2010 May 1900 (has links)
In recent years, there have been several research endeavors to increase the ability to identify and quantify special nuclear material in field measurements. These have included both gamma spectroscopy and neutron coincidence systems that are portable and work in a variety of environments. In this work, a Monte Carlo Neutral Practicle X (MCNPX) model was used to design an instrument that includes four gamma detection slabs placed within four neutron detection slabs. The combination of gamma spectroscopy and neutron coincidence counting in a single instrument allows for direct measurement of plutonium (Pu) mass without need for assumptions or operator declarations. A combined neutron-gamma instrument was designed for use in characterizing and quantifying Pu in field samples. This detector consists of a plastic scintillator containing LaBr3 nanoparticles and a polyethylene slab containing four 3He tube detectors. The system was tested via simulation with MCNPX for four Pu samples of known quality and quantity. These samples had masses ranging from 100-300 g of Pu. It was found that the designed detector system could be used to determine 240Pu-effective mass to within 3.5% accuracy and to characterize the isotopic content of the Pu to within 2% accuracy for all isotopes except for 238Pu and 242Pu. The system could determine 238Pu isotopic content to within 14% accuracy but is completely unable to determine 242Pu content. This system has the ability to Four Plutonium (Pu) samples of known quantity were modeled and tested to determine what data was available from each individual signature. Each model included a separate MCNPX deck for each individual isotope that contributes to the gamma signature in photon mode and a spontaneous fission and (alpha,n) deck for the neutron signature. The first three samples were used to create spectrums and efficiency curves for each odd isotope as well as for a Pu effective mass for the neutron signature. The data from these simulations were then used to identify the isotopics in the fourth sample to within acceptable accuracy. From this data, a total Pu mass was obtained as well as an ability to determine the ratio of (alpha,n) to spontaneous fission neutrons without additional simulations. This provides a new method to detect and identify the Pu content within a sample without producing requiring supplemental additional information since isotopics can be determined with the combined use of the gamma and neutron systems.
54

Development of Self-Interrogation Neutron Resonance Densitometry (SINRD) to Measure the Fissile Content in Nuclear Fuel

Lafleur, Adrienne 2011 August 1900 (has links)
The development of non-destructive assay (NDA) capabilities to directly measure the fissile content in spent fuel is needed to improve the timely detection of the diversion of significant quantities of fissile material. Currently, the International Atomic Energy Agency (IAEA) does not have effective NDA methods to verify spent fuel and recover continuity of knowledge in the event of a containment and surveillance systems failure. This issue has become increasingly critical with the worldwide expansion of nuclear power, adoption of enhanced safeguards criteria for spent fuel verification, and recent efforts by the IAEA to incorporate an integrated safeguards regime. In order to address these issues, the use of Self-Interrogation Neutron Resonance Densitometry (SINRD) has been developed to improve existing nuclear safeguards and material accountability measurements. The following characteristics of SINRD were analyzed: (1) ability to measure the fissile content in Light Water Reactors (LWR) fuel assemblies and (2) sensitivity and penetrability of SINRD to the removal of fuel pins from an assembly. The Monte Carlo Neutral Particle eXtended (MCNPX) transport code was used to simulate SINRD for different geometries. Experimental measurements were also performed with SINRD and were compared to MCNPX simulations of the experiment to verify the accuracy of the MCNPX model of SINRD. Based on the results from these simulations and measurements, we have concluded that SINRD provides a number of improvements over current IAEA verification methods. These improvements include: 1) SINRD provides absolute measurements of burnup independent of the operator’s declaration. 2) SINRD is sensitive to pin removal over the entire burnup range and can verify the diversion of 6% of fuel pins within 3σ from LWR spent LEU and MOX fuel. 3) SINRD is insensitive to the boron concentration and initial fuel enrichment and can therefore be used at multiple spent fuel storage facilities. 4) The calibration of SINRD at one reactor facility carries over to reactor sites in different countries because it uses the ratio of fission chambers (FCs) that are not facility dependent. 5) SINRD can distinguish fresh and 1-cycle spent MOX fuel from 3- and 4-cycles spent LEU fuel without using reactor burnup codes.
55

An automated damage detection system for armoured vehicle launched bridge

Sazonov, Eduard S. January 2002 (has links)
Thesis (Ph. D.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xi, 187 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 148-154).
56

A focused, two dimensional, air-coupled ultrasonic array for non-contact generation

Blum, Frank, January 2003 (has links) (PDF)
Thesis (M.S. in E.S.M.)--School of Civil and Environmental Engineering, Georgia Institute of Technology, 2004. Directed by Laurence Jacobs. / Includes bibliographical references (leaves 111-114).
57

Novel application of micro-and non-destructive analytical techniques for the analysis of Iron Age glass beads from North-Eastern Scotland

Bertini, Martina January 2012 (has links)
No description available.
58

Nondestructive determination of unknown pile tip elevations using modal analysis

Hughes, Mary Leigh 05 1900 (has links)
No description available.
59

Thermoelastic modeling of laser generated ultrasound for nondestructive materials testing

Sanderson, Terry 12 1900 (has links)
No description available.
60

Propagation of guided waves in adhesive bonded components

Seifried, Robert 08 1900 (has links)
No description available.

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