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The Design, Development And Evaluation Of An Electronic Performance Support System (epss) For The Crime Scene Investigation UnitYakin, Ilker 01 December 2012 (has links) (PDF)
The purpose of this study is to design, develop and evaluate an electronic performance support system (EPSS) for the crime scene investigation unit (CSI). For this purpose, a sequential explanatory strategy as a procedure of the mixed method design was used in analysis and evaluation of the EPSS. The research was composed of three main phases: analysis / design, development and implementation, and evaluation of the EPSS. In first phase composed of performance and cause analyses, the CSI Unit&rsquo / s existing information, and contributing causal performance factors based on Gilbert&rsquo / Behavior Engineering Model were explored. In performance analysis phase, official documentation of the CSI Unit was reviewed. As for cause analysis, the survey and focus group interviews were conducted to 1176 and 22 CSI officers, respectively. These data were analyzed using with both quantitative and qualitative methods to facilitate the selection of the most appropriate intervention and its components. Analyses results revealed that 14 basic influences grouped under the workplace and competency on human behavior impacted performance of the officers. Based on these results, an EPSS composed of intrinsic, extrinsic and external levels, and support components was designed and developed in the second phase. Having been implemented, the evaluation of the EPSS based on the Kirkpatrick&rsquo / Four Levels of Evaluation Model was conducted
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to determine the overall impact, perceived benefits, and effectiveness of the intervention in third phase. In this phase, a survey, interviews, computer logs and a checklist were used so as to assess the accomplishment of the EPSS. While the survey and the checklist were administered to the 191 officers and 2 experts from the field, the interviews were conducted with 12 officers. Evaluation results admitted that the CSI officers&rsquo / reactions were very positive to the EPSS. While, an intrinsic support made a major contribution to their productivity, establishing standardization would be perceived as the major impact of the EPSS. Lastly, increasing identity and simplifying criminal justice system were the two main impact factors on the society that the system would influence positively.
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Variación térmica de la resistividad eléctrica en nuevos materiales metálicos: compuestos de tierras raras y aleaciones amorfasRodríguez Fernández, Jesús 16 May 1987 (has links)
En la presente memoria se describe el método para la medida de la variación térmica de la resistividad entre 10 y 300 K que hemos puesto a punto en nuestros laboratorios de la Universidad de Cantabria. Dicho método es el de cuatro puntas con corriente alterna y detección síncrona. También se analizan, mediante el método de los elementos finitos, los efectos de la geometría de la muestra y posición de los contactos en la relación entre la resistividad observada experimentalmente y la resistividad real, haciendo hincapié en el caso de muestras anisótropas. Posteriormente aplicamos esta técnica al estudio de diversas series de materiales:
1) Los compuestos RPt que cumplen la Ley de De Gennes y en los que hemos podido determinar los valores de la masa efectiva m* y de la constante de canje.
2) Los compuestos RNi2Si2 en las que se puede observar una relación entre la resistividad magnética y las estructuras magnéticas.
3) Los compuestos CeyLa1-yNixPt1-x, en las que se estudia el efecto Kondo
4) Los amorfos metálicos (Co1-x(Fe5Ni5)x)75Si15B10 en los que se observa un mínimo en la resistividad a bajas temperaturas así como variaciones en lnT, T2 y T a temperaturas bajas, intermedias y altas respectivamente / The present report describes the method for measuring the temperature dependence of the resistivity between 10 and 300 K that we have developed in our laboratories at the University of Cantabria. This is a four-probe method using ac current and synchronous detection. Also it is analyzed, using the finite element method, the effects of the sample geometry and contacts position in the relationship between the real resistivity and resistivity observed experimentally, even in the case of anisotropic samples. Subsequently we apply this technique to the study of different family of materials:
1) RPt compounds which follow the De Gennes Law, allowing us to determine the values of the effective mass m * and exchange constant.
2) The compounds RNi2Si2 in which it is possible to establish a relationship between the magnetic resistivity and the magnetic structures.
3) The compounds CeyLa1-yNixPt1-x, in which we study the Kondo effects.
4) The amorphous Co1-x(Fe5Ni5)x)75Si15B10 metals, in which there is a minimum in the resistivity at low temperatures as well as variations in LnT, T2 and T at low, intermediate and high temperatures respectively.
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Coherent Spin Dynamics of a Spin-1 Bose-Einstein CondensateChang, Ming-Shien 11 April 2006 (has links)
Bose-Einstein condensation (BEC) is a phenomenon in which identical bosons occupy the same quantum state below a certain critical temperature. A hallmark of BEC is the coherence between particles every particle shares the same quantum wavefunction and phase. This coherence has been demonstrated for the external (motional) degrees of freedom of the atomic condensates by interfering two condensates. In this thesis, the coherence is shown to extend to the internal spin degrees of freedom of a spin-1 Bose gas evidenced by the observed coherent and reversible spin-changing collisions. The observed coherent dynamics are analogous to Josephson oscillations in weakly connected superconductors and represent a type of matter-wave four-wave mixing. Control of the coherent evolution of the system using magnetic fields is also demonstrated. The studies on spinor condensates begin by creating spinor condensates directly using all-optical approaches that were first developed in our laboratory. All-optical formation of Bose-Einstein condensates (BEC) in 1D optical lattice and single focus trap geometries are developed and presented. These techniques offer considerable flexibility and speed compared to magnetic trap approaches, and the trapping potential can be essentially spin-independent and are ideally suited for studying spinor condensates. Using condensates with well-defined initial non-equilibrium spin configuration, spin mixing of F = 1 and F = 2 spinor condensates of rubidium-87 atoms confined in an optical trap is observed. The equilibrium spin configuration in the F = 1 manifold confirms that 87Rb is ferromagnetic. The coherent spinor dynamics are demonstrated by initiating spin mixing deterministically with a non-stationary spin population configuration. Finally, the interplay between the coherent spin mixing and spatial dynamics in spin-1 condensates with ferromagnetic interactions is investigated.
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人口動態と富裕 : 貧困認識をめぐる文明史論と政治算術 : 18 世紀スコットランド、イングランド経済思想の一側面FUKAGAI, Yasunori, 深貝, 保則 31 March 2010 (has links)
No description available.
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In-Medium QCD Sum Rules for omega Meson, Nucleon and D Meson / QCD-Summenregeln für im Medium modifizierte omega-Mesonen, Nukleonen und D-MesonenThomas, Ronny 29 January 2009 (has links) (PDF)
The modifications of hadronic properties caused by an ambient nuclear medium are investigated within the scope of QCD sum rules. This is exemplified for the cases of the omega meson, the nucleon and the D meson. By virtue of the sum rules, integrated spectral densities of these hadrons are linked to properties of the QCD ground state, quantified in condensates. For the cases of the omega meson and the nucleon it is discussed how the sum rules allow a restriction of the parameter range of poorly known four-quark condensates by a comparison of experimental and theoretical knowledge. The catalog of independent four-quark condensates is covered and relations among these condensates are revealed. The behavior of four-quark condensates under the chiral symmetry group and the relation to order parameters of spontaneous chiral symmetry breaking are outlined. In this respect, also the QCD condensates appearing in differences of sum rules of chiral partners are investigated. Finally, the effects of an ambient nuclear medium on the D meson are discussed and relevant condensates are identified. / Die Veränderungen von Hadroneneigenschaften durch ein umgebendes nukleares Medium (Kernmaterie) werden mit der Methode der QCD-Summenregeln untersucht. Dies wird am Beispiel des omega-Mesons, des Nukleons und des D-Mesons vorgeführt. Durch die Summenregeln werden integrierte Spektraldichten dieser Hadronen in Beziehung zu Eigenschaften des QCD-Grundzustandes, quantifiziert in Kondensaten, gesetzt. Diskutiert wird am Beispiel des omega-Mesons und des Nukleons, wie diese Summenregeln eine Einschränkung des Parameterbereiches von wenig bekannten Vierquark-Kondensaten durch Vergleich von experimentellen und theoretischen Erkenntnissen erlauben. Ein Katalog unabhängiger Vierquark-Kondensate wird aufgestellt und Relationen zwischen diesen Kondensaten werden deutlich gemacht. Das Verhalten der Vierquark-Kondensate unter der chiralen Symmetriegruppe und der Zusammenhang mit Ordnungsparametern spontaner chiraler Symmetriebrechung werden behandelt. In dieser Hinsicht werden auch die in Differenzen der Summenregeln chiraler Partner eingehenden QCD-Kondensate untersucht. Schließlich werden die Effekte endlicher Kerndichten beim D-Meson diskutiert und relevante Kondensate identifiziert.
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Programmable and Tunable Circuits for Flexible RF Front EndsAhsan, Naveed January 2008 (has links)
<p>Most of today’s microwave circuits are designed for specific function and specialneed. There is a growing trend to have flexible and reconfigurable circuits. Circuitsthat can be digitally programmed to achieve various functions based on specific needs. Realization of high frequency circuit blocks that can be dynamically reconfigured toachieve the desired performance seems to be challenging. However, with recentadvances in many areas of technology these demands can now be met.</p><p>Two concepts have been investigated in this thesis. The initial part presents thefeasibility of a flexible and programmable circuit (PROMFA) that can be utilized formultifunctional systems operating at microwave frequencies. Design details andPROMFA implementation is presented. This concept is based on an array of genericcells, which consists of a matrix of analog building blocks that can be dynamicallyreconfigured. Either each matrix element can be programmed independently or severalelements can be programmed collectively to achieve a specific function. The PROMFA circuit can therefore realize more complex functions, such as filters oroscillators. Realization of a flexible RF circuit based on generic cells is a new concept.In order to validate the idea, a test chip has been fabricated in a 0.2μm GaAs process, ED02AH from OMMIC<sup>TM</sup>. Simulated and measured results are presented along withsome key applications like implementation of a widely tunable band pass filter and anactive corporate feed network.</p><p>The later part of the thesis covers the design and implementation of tunable andwideband highly linear LNAs that can be very useful for multistandard terminals suchas software defined radio (SDR). One of the key components in the design of a flexibleradio is low noise amplifier (LNA). Considering a multimode and multiband radiofront end, the LNA must provide adequate performance within a large frequency band.Optimization of LNA performance for a single frequency band is not suitable for thisapplication. There are two possible solutions for multiband and multimode radio frontends (a) Narrowband tunable LNAs (b) Wideband highly linear LNAs. A dual bandtunable LNA MMIC has been fabricated in 0.2μm GaAs process. A self tuningtechnique has also been proposed for the optimization of this LNA. This thesis alsopresents the design of a novel highly linear current mode LNA that can be used forwideband RF front ends for multistandard applications. Technology process for thiscircuit is 90nm CMOS.</p>
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Modélisation dynamique et supervision des fours de réchauffage continus de la sidérurgieAbdo, Diala 10 1900 (has links) (PDF)
Ce travail porte sur la modélisation dynamique des fours de réchauffage en continu de la sidérurgie en développant une logique de supervision en ligne. Le premier axe présente l'élaboration d'un modèle dynamique global d'un four de réchauffage où seules l'équation de l'énergie et l'équation de continuité sont appliquées en utilisant et perfectionnant le logiciel THERMETTE du Centre Energétique et Procédés (CEP). Le modèle est applicable à tous les types de fours grâce à l'interface de l'outil SAFIR-4D développé pour la société Stein-Heurtey. A l'aide de cette interface, un four quelconque est décrit et le modèle dynamique est généré automatiquement après avoir calculé les facteurs de transferts radiatifs du four étudié. Les facteurs de transferts sont calculés par la méthode "Damier", méthode de calcul rapide des facteurs de transferts radiatifs développée dans cette thèse, couplée au logiciel MODRAY du CEP. La validation numérique de la méthode "Damier" est effectuée afin d'en démontrer son exactitude avec ce qu'elle apporte comme gain considérable en temps de calcul. La validation expérimentale, basée sur une brame instrumentée circulant dans un four, montre la cohérence du modèle dynamique global mis en place et couplé aux facteurs de transferts radiatifs issus de la méthode "Damier". Les résultats obtenus de températures, de débits de produits et de bilan thermique sont en bon accord avec les mesures. Le second grand axe de ce travail porte sur la supervision en ligne d'un four de réchauffage. Le modèle dynamique développé dans la première partie sert d'analogue de four réel et donc de fournisseur de données pour le fonctionnement en ligne du four. Le travail de supervision est une combinaison d'algorithmes de prévision et d'optimisation. La prévision rapide et en ligne des températures des brames permet d'obtenir les données nécessaires à l'optimisation dont la fonction est de mettre à jour les consignes du four afin de vérifier le critère technico-économique de production. La supervision est ensuite validée en comparant les résultats des tests menés à ceux obtenus lors d'une supervision classique où les consignes des zones ont des valeurs constantes. Les résultats sont satisfaisants du point de vue consommation énergétique et critère de températures sur les différentes brames.
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Multidimensional Spectroscopy of Semiconductor Quantum DotsBylsma, Jason Michael 01 January 2012 (has links)
The coherent properties of semiconductor nanostructures are inherently difficult to measure and one-dimensional spectroscopies are often unable to separate inhomogeneous and homogeneous linewidths. We have refined and improved a method of performing multidimensional Fourier transform spectroscopy based on four-wave
mixing (FWM) experiments in the box geometry. We have modified our system with broadband beamsplitters in all interferometer arms, high-resolution translation stages and the ability to work in reflection geometry. By improving the phase-stability of our setup and scanning pulse delays with sub-optical cycle precision, we are able to
reproduce 2DFT spectra of GaAs multiple quantum wells. With the FWM signal reflected from the sample surface instead of transmitted through, we show that very low pulse powers can be used to generate coherent 2D signals from colloidal PbS quantum dots. Dephasing times are particularly difficult to measure in small colloidal quantum dots due to environmental broadening effects from the colloidal growth. We show that low-temperature pure excitonic dephasing can be measured via time-integrated measurements as well as from the cross-diagonal linewidths of 2DFT spectra. Ultrafast
sub-picosecond dephasing times are measured at 5 K in 3 nm PbS quantum dots, while excitation-density-dependence is investigated in these dots. By retrieving the global phase with an all-optical method, we are able to retrieve the real-part 2D spectra of PbS quantum dots.
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The effects of graphic organizers and explicit instruction on the informational text learning and comprehension of fourth- and fifth- grade students with learning disabilitiesCiullo, Stephen Paul 01 February 2012 (has links)
This single-case study compared the effects of a typical practice baseline phase to those of a treatment phase. Seven students with learning disabilities (LD) in Grades 4 and 5 participated in the two-school-site study. Each student had basic word-reading proficiency and a distinct deficit in comprehension. Baseline lessons consisted of text reading with corrective feedback, a text-based summary with corrective feedback, and a daily quiz. In treatment, students read text with corrective feedback, used a graphic organizer to study and teach the content to the instructor, and completed a daily quiz. The baseline and treatment lessons were influenced by direct, systematic, and explicit instruction.
Analysis indicates that an experimental effect was present for all students when the daily quiz results for baseline and treatment phases are compared. Percentage of non-overlapping data (PND) results were 100% for five students, which is characterized as a highly effective treatment according to single-case standards. Two students had minimal overlap between baseline and treatment, but their scores indicate that the treatment was effective at improving informational text learning. On a cumulative pre/post social studies test, students at School A improved from 26% to 56%, and at School B, students scored 28% on pretest and 81% on posttest. Results indicate that treatment components that were previously effective for students with LD in secondary school are promising for enhancing informational text learning for students in upper elementary school. A social validity questionnaire indicated that students perceived graphic organizers as an efficacious practice for improving learning potential. / text
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Arthur Bliss's emerging voice : a study of two song cycles on texts by Li PoJohnson, Mary Ellen 23 June 2011 (has links)
Not available / text
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