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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.
111

Nusikalstamų veikų daugetas Lietuvos baudžiamojoje teisėje / Multiple Offenses in Criminal Law of Lithuania

Girdenis, Tomas 27 December 2010 (has links)
Tiriamoji problema Šiame darbe yra tiriama nusikalstamų veikų daugeto instituto problematika. Nusikalstamų veikų daugetas kaip baudžiamosios teisės institutas pasižymi tuo, kad savyje apjungia tiek nusikalstamų veikų kvalifikavimo, tiek ir baudžiamosios atsakomybės individualizavimo problemas. Su nusikalstamų veikų kvalifikavimo problemomis yra susiduriama tada, kai yra sprendžiami pavienės nusikalstamos veikos atribojimo nuo nusikalstamų veikų daugeto klausimai. Konstatavus nusikalstamų veikų daugeto egzistavimą, yra būtina pereiti prie kitos problemos sprendimo – baudžiamosios atsakomybės individualizavimo. Baudžiamosios atsakomybės individualizavimas priklauso nuo nusikalstamų veikų daugeto formos. Taigi vieningai teismų praktikai formuoti yra būtini vienodi ir aiškūs nusikalstamų veikų daugeto formų išskyrimo bei tarpusavio atribojimo kriterijai. Apibrėžus nusikalstamų veikų daugeto formas, yra būtina nustatyti ir jų įtaką asmens, padariusio nusikalstamas veikas, baudžiamajai atsakomybei. Žinoma, pagrindinė įtaka baudžiamajai atsakomybei pasireiškia per bausmių bendrinimo taisykles, tačiau reikia nepamiršti ir kitų aktualių klausimų (tokių kaip bausmės vykdymo atidėjimas, lygtinis atleidimas nuo laisvės atėmimo bausmės prieš terminą ir neatliktos laisvės atėmimo bausmės dalies pakeitimas švelnesne bausme, apkaltinamojo nuosprendžio priėmimo senatis ir t.t.), kurių sprendimas vienaip ar kitaip priklauso nuo nusikalstamų veikų daugeto buvimo. Ne gana to, kartais tenka... [toliau žr. visą tekstą] / Research problem In the present doctoral dissertation, the problematic issues of the institute of multiple offences are analysed. Multiple offences as an institute of criminal law is characterised as involving the problems of both the qualification of criminal offences and the individualisation of criminal liability. The problems of the qualification of criminal offences are relevant, when questions of the separation of single criminal acts from multiple offences are dealt with. When the existence of multiple offences is established, it is necessary to move on to the consideration of another problem—the individualisation of criminal liability. The individualisation of criminal liability depends on the form of multiple offences. Therefore, for the formation of a uniform case-law, homogeneous and clear criteria for the differentiation of the forms of multiple offences and their separation form each other are essential. When the forms of multiple offences are defined, it is necessary to evaluate their impact on the criminal liability of the person who committed the criminal act. Of course, the key influence on criminal liability manifests through the rules of the combination of sentences; however, one should not forget other topical issues (such as sentence suspension, release from a custodial sentence on parole and the replacement of the term not served of the custodial sentence with a more lenient penalty, statute of limitations of a judgement of conviction, etc.) the... [to full text]
112

Test of fast neutron detectors for spectroscopy with (3He,n) two proton stripping reactions

Elbasher, Mohamed Elbasher Ahmed 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Nine 100x100x600 mm3 plastic scintillators, formerly built for the neutron time of ight measurements at iThemba LABS, were refurbished. The position resolution of these detectors was determined using muon cosmic rays and coincident measurement techniques. Average position resolution of 4.28 cm (FWHM) was found. In order to predict the time spectrum of the large-volume detector Monte Carlo simulations have been performed. These simulations aimed at anticipating the separation of statistical neutrons, prompt gamma rays and uncorrelated gamma rays from the fast neutrons emitted in the reaction of interest. One of the neutron detectors was tested using fast neutrons from the 232Th( ,xn) reaction at 42 MeV. Statistical neutrons from fusion evaporation reactions were produced in 152Sm(12C,xn) fusion evaporation reaction. Coincidences between neutrons and gamma rays were successfully identi ed. Prompt gamma rays and uncorrelated gamma rays were also identi ed. / AFRIKAANSE OPSOMMING: Nege 100x100x600 mm3 plastiese scintillators, wat aanvanklik gebou was vir neutron vlugtyds meetings by iThemba LABS, was hernu. Die posisie resolusie van die detektore was bepaal deurmiddel van muon kosmiese straling en koïnsidensie meet tegnieke. Posisie resolusie van 4.28 cm (FWHM) was verkry. Monte Carlo simulasies is gebruik om die posisie resolusie van'n groot volume detektor te voorspel. Hierdie simulasies is daarop gemik om onderskeid te maak tussen statistiese neutrone, gelyktydige gamma strale en ongekorreleerde gamma strale vanaf vinnige neutrone in die reaksie van belang uitgestraal word. Een neutron detektor was getoets deur gebruik te maak van vinnige neutrone wat uit die reaksie 232Th( ,xn) by 42 MeV ontstaan. Statistiese neutrone vanaf splitsings verdampingsreaksies, gelyktydige gamma strale en ongekorreleerde gamma strale was geidenti seer. Statistiese neutrone van samesmelting verdamping reaksies was geproduseer in die reaksie 152Sm(12C,xn). Toeval tussen neutrone en gamma strale was suksesvol geïdenti seer, gevra gamma strale en ongekorreleerd gamma strale was ook geïdenti seer.
113

Experimental Techniques for Studies in Atomic & Molecular Physics

Heijkenskjöld, Filip January 2008 (has links)
<p>This thesis is based on a selection of six different experimental techniques used for studies in atomic and molecular physics. The techniques analysed in the thesis are compared to find similarities in strategies and ways to avoid sources of error.</p><p>Paper 1 deals with collision based spectroscopy with 60 keV Xe6+ ions on sodium and argon gas targets. Information on energy of Rydberg states in Xe5+ is unveiled by optical spectroscopy in the wavelength range from vacuum ultraviolet (VUV) to visible. In paper 2, the fast ion-beam laser spectroscopy (FIBLAS) is adapted for measuring hyperfine structure of barium isotopes in an isotopically pure ion-beam. This techniques involves changing the isotope during the measurement to minimize sources of error in measurement and enhance the signal from lesser abundant isotopes. The FIBLAS technique is used in paper 3 to study samarium ions. The ions are optically pumped and the recorded optical nutation is used to measure transition probabilities. This technique eludes the difficulties inherent in relative intensity measurements of all the radiative transitions from an excited state. In Paper 4, optical emission spectroscopy is used in the VUV region to study noble gas mixture discharges. The source of the emission bands near the resonance lines of krypton and xenon are found to be heteronuclear dimers. In paper 5, radiation from a pulsed argon plasma with admixture of nitrogen is studied with time resolved spectroscopy in the VUV and ultraviolet wavelength ranges to investigate the mechanism of energy transport. A metastable state of atomic argon is found to be an important source of energy to many radiative processes. In Paper 6, photoelectron spectroscopy (PES) on thiophene, on 3-bromothiophene and on 3,4-dibromothiophene using time-of-flight photoelectron-photoelectron coincidence technique and conventional PES to investigate the onset of double ionisation compared to the onset of single ionisation in molecules.</p>
114

Effets de la contrainte temporelle sur la coordination posture/mouvement : particularité d'une situation d'anticipation-coïncidence / Effects of the temporal constraint on the coordination posture/movement : specificity of the anticipation-coincidence situation

Ilmane, Nabil 11 March 2009 (has links)
Les mouvements volontaires sont accompagnés par des ajustements posturaux anticipateurs (APAs). Leur rôle consiste à prévenir et à compenser de possibles perturbations du corps provoquées par l’exécution du mouvement. Des études antérieures ont montré que la coordination posture / mouvement est modifiée selon que le mouvement est exécuté le plus rapidement possible en réponse à un signal externe (réactif :TRS), ou que le mouvement est auto-initié (prédictif :AI). L’objectif de ce travail est d’examiner le mode de coordination posture / mouvement impliqué dans une situation d’anticipation-coïncidence (AC) lors de l’exécution de mouvements simples et complexes, et ensuite, comparer ce mode aux modes TRS et AI. Trois études expérimentales ont été menées pour vérifier si : (1) les modes de coordination, obtenus sur des gestes simples, s’étendent à des mouvements complexes ; (2) le mode de coordination en AC dépend des caractéristiques temporelles du mobile utilisé dans la tâche ; (3) les commandes impliquant les APAs et le mouvement focal sont associées ou dissociées en fonctions des contraintes temporelles TRS et AC. Ainsi, nous avons démontré que : (1) les stratégies de coordination posture / mouvement s’appliquent sur les mouvements complexes ; (2) la prédictibilité du moment de déclenchement dans la condition AC rapproche celle-ci de la situation AI ; (3) les différences de coordination entre les conditions réactive (TRS) et prédictives (AC, AI) sont liées à des différences dans les mécanismes de préparation consistant à dissocier les commandes posturales et focales en situation prédictive et à associer ces commandes dans la situation réactive. Les implications théoriques qui émergent de ces résultats sont discutées. / Voluntary movements are generally accompanied by anticipatory postural adjustments (APAs). They are centrally generated as a feedforward mechanism to counteract the mechanical effects of predicted balance perturbations. Previous studies showed that the coordination between posture and movement is modified depending on whether the movement is performed in a reactive temporal pressure (TRS) or in a self-initiated (AI) manner. The aim of this thesis is to examine the coordination of posture and movement in anticipation-coincidence (AC) timing tasks in simple and complex movements, and then to compare this mode to the TRS and AI modes. Three experiments was achieved to verify : (1) whether simple movement coordination modes can be extended to complex movements ; (2) whether the temporal characteristics of the mobile used in the task modifies the coordination in AC condition ; (3) to which extent the motor commands of APAs and the focal movement are coupled in response to the TRS and AC temporal pressures. Results show that: (1) the different strategies of coordination between posture and movement are extended to the complex tasks; (2) the predictable timing of movement execution in the AC condition generates behaviours closer to those observed in AI condition; (3) the differences in the coordination between the reactive (TRS) and the predictive (AC, AI) conditions are related to the difference in the preparatory processes which consists on the dissociation of postural and focal commands in the predictive situations, and the association of this motor commands in the reactive situation. Theoretical implications emerging from these results are discussed.
115

Sobre teoremas de equilíbrio de Nash / On Nash equilibrium theorems

Monis, Thais Fernanda Mendes 27 August 2010 (has links)
Nesse trabalho, aplicando métodos da Topologia Algébrica, nós obtivemos novas versões do teorema de equilíbrio de Nash. Nós definimos um conceito de equilíbrio local para jogos não cooperativos, o chamado equilíbrio local fraco, e demonstramos sua existência quando os espaços de estratégia são variedades diferenciáveis e as funções payoff são continuamente diferenciáveis. Nós demonstramos a ineficiência do equilíbrio local fraco no sentido de Pareto / In this work, applying methods of Algebraic Topology, we obtain new versions of the Nash equilibrium theorem. We define a concept of local equilibrium for non-cooperative games, the socalled weak local equilibrium, and we prove its existence when the spaces of strategies are differentiable manifolds and the payoff functions are continuously differentiable. We prove the ineffciency of weak local equilibrium in the Pareto sense
116

Estudo de mecanismos de reação nuclear no sistema 7Li+120Sn utilizando coincidências -partícula / studies on nuclear reactions mechanisms in the system 7Li+120Sn using gamma-particle coincidences

Zagatto, Vinicius Antonio Bocaline 02 April 2015 (has links)
Medidas em coincidência gamma-partícula da reação 7Li+120Sn foram realizadas na faixa de energia de 2.6 a 3.9 MeV por nucleon. Além do canal inelástico, foram observados os canais de pick-up de próton e stripping de um e dois nêutrons, sendo que, para o último caso, cálculos teóricos de DWBA e CRC comparados com o canal elástico demonstram que esta transferência ocorre de maneira sequencial (two-step) e não direta. Este trabalho consolida a existência de canais já anteriormente observados (pick-up de próton e stripping de um nêutron) além de observar pela primeira vez a existência do canal de strippinp de dois nêutrons, no entanto, ele tem um caráter pioneiro pois é o primeiro a medir distribuições angulares de todos esses canais. Tanto o pick-up de próton quanto o stripping de dois nêutrons tiveram de levar em conta na análise cálculos de Monte Carlo que simulassem o efeito da quebra dos projéteis 8Be e 5Li, respectivamente. Fatores espectroscópicos para alguns estados desses canais foram obtidos e são condizentes com os valores esperados considerando o modelo de single particle e a indistinguibilidade de partículas nos casos dos núcleos 119In e 122Sn. Por outro lado, são muito pequenos (ordem de 10e-2) para estados do 121Sn, fato esse gerado pela provável falta de acoplamento de mais canais de reação que reduzem o fluxo da transferência de nêutron. Foram observados também núcleos gerados a partir da transferência seguida de emissão de partículas. / $\\gamma$-particle coincidence measurements of the $^7$Li$+^{120}$Sn reaction were made in the $2.6$ to $3.9$ MeV/nucleon energy range. Besides the inelastic channel, the proton {\\it pick-up} and one/two neutron {\\it stripping} were observed, whereas, for the last case, DWBA and CRC calculations were compared to experimental elastic scattering data and demonstrated that this transfer occurs in a sequential ({\\it two-step}) rather than a direct way. This work consolidates the existence of some channels that have already been observed (proton {\\it pick-up} and neutron {\\it stripping}) and also observes for the first time the existence of the two neutron {\\it stripping} channel, however, it still retains its pioneering as it is the first one to measure the angular distributions for all these channels. The proton {\\it pick-up} and the two neutron {\\it stripping} channels had to take into account in their analysis Monte Carlo calculations to simulate the projectile breaking effect ($^8$Be and $^5$Li, respectively). Spectroscopic factors for some states of these channels were found and are consistent with the expected values considering the {\\it single particle} model and the particle indistinguishability for the $^{119}$In and $^{122}$Sn cases, however, these factors are too small (magnitude order of $10^{-2}$) for the $^{121}$Sn case. This was generated most likely by the lack of coupling of some of the reaction channels that would reduce the one neutron transfer flux. Nuclei generated by the transfer followed by particle emission were also observed.
117

Padronização de Ga-68 em sistema de coincidências 4&pi;&beta;-&gamma; / 68Ga standardization by means of a 4&pi;&beta;-&gamma; coincidence system

Lacerda, Flavio William 20 February 2013 (has links)
O presente trabalho tem como objetivo a padronização de 68Ga, um emissor de pósitrons de meia-vida curta, usado em PET (Tomografia por Emissão de Pósitrons). A padronização do 68Ga foi realizada em um sistema de coincidência 4&pi;&beta;-&gamma;, que consiste de um detector proporcional em geometria 4&pi; a gás fluente acoplado a um detector de cristal semicondutor HPGe, para a detecção de raios gama. A aquisição de dados foi realizada por meio de um Sistema de Coincidência por Software (SCS), desenvolvido no Laboratório de Metrologia Nuclear (Laboratório de Metrologia Nuclear - LMN) no IPEN-CNEN / SP. Os resultados finais foram obtidos a partir de um ajuste de curva multiparamétrica aplicando-se uma metodologia que leva em consideração a matriz de covariância combinando os resultados experimentais com aqueles determinados pela simulação Monte Carlo. / The present work aims the standardization of 68Ga, a positron emitter of short half-life used in PET (Positron Emission Tomography). The 68Ga standardization was performed in a 4&pi;&beta;-&gamma; coincidence system that consists of a gas-flow proportional counter (PC) in 4&pi; geometry coupled to a HPGe crystal, for gamma-ray detection. The data acquisition was carried out by means of a Software Coincidence System (SCS) developed at the Nuclear Metrology Laboratory (Laboratório de Metrologia Nuclear LMN) at the IPEN-CNEN/SP. The final results were obtained from a multiple curve fitting applying a covariance matrix methodology combining experimental results with those determined by the Monte Carlo simulation.
118

Padronização de Ga-68 em sistema de coincidências 4&pi;&beta;-&gamma; / 68Ga standardization by means of a 4&pi;&beta;-&gamma; coincidence system

Flavio William Lacerda 20 February 2013 (has links)
O presente trabalho tem como objetivo a padronização de 68Ga, um emissor de pósitrons de meia-vida curta, usado em PET (Tomografia por Emissão de Pósitrons). A padronização do 68Ga foi realizada em um sistema de coincidência 4&pi;&beta;-&gamma;, que consiste de um detector proporcional em geometria 4&pi; a gás fluente acoplado a um detector de cristal semicondutor HPGe, para a detecção de raios gama. A aquisição de dados foi realizada por meio de um Sistema de Coincidência por Software (SCS), desenvolvido no Laboratório de Metrologia Nuclear (Laboratório de Metrologia Nuclear - LMN) no IPEN-CNEN / SP. Os resultados finais foram obtidos a partir de um ajuste de curva multiparamétrica aplicando-se uma metodologia que leva em consideração a matriz de covariância combinando os resultados experimentais com aqueles determinados pela simulação Monte Carlo. / The present work aims the standardization of 68Ga, a positron emitter of short half-life used in PET (Positron Emission Tomography). The 68Ga standardization was performed in a 4&pi;&beta;-&gamma; coincidence system that consists of a gas-flow proportional counter (PC) in 4&pi; geometry coupled to a HPGe crystal, for gamma-ray detection. The data acquisition was carried out by means of a Software Coincidence System (SCS) developed at the Nuclear Metrology Laboratory (Laboratório de Metrologia Nuclear LMN) at the IPEN-CNEN/SP. The final results were obtained from a multiple curve fitting applying a covariance matrix methodology combining experimental results with those determined by the Monte Carlo simulation.
119

Soft X-ray Scattering Dynamics Close to Core Ionization Thresholds in Atoms and Molecules

Söderström, Johan January 2007 (has links)
<p>In this Thesis studies of highly excited states in gas-phase atoms and molecules (He, Ne, N<sub>2</sub>, O<sub>2</sub>, N<sub>2</sub>O and CO<sub>2</sub>) using a variety of synchrotron-radiation based techniques are presented. The three techniques used most frequently are X-ray-emission-threshold-electron coincidence (XETECO), X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) and they are all given a brief introduction. </p><p>The fluorescence yield (FY) from doubly excited states in helium near the N=2 threshold(s) has been investigated in weak static external magnetic and electric fields, but also in a field free environment. The FY spectra in weak static magnetic fields show the importance of including the diamagnetic interaction in the theoretical models. The presence of weak static electric fields shows that even weak fields (as low as 44 V/cm) has a great impact on the observed FY spectra. Resonant XES spectra from some of the first doubly excited states in helium has been recorded in a field free environment, and compared to theory.</p><p>The XETECO technique is presented and the first XETECO results from Ne, N<sub>2</sub>, O<sub>2</sub>, CO<sub>2</sub> and N<sub>2</sub>O are shown, together with interpretations of possible threshold dynamics. I show that XETECO can be interpreted as threshold photoelectron spectra free from post collision interaction, and can hence be compared to above threshold XPS measurements. The observed below-threshold structures in the XETECO spectra are discussed and given a tentative explanation. The results from the analysis of the N<sub>2</sub>O XETECO spectrum lead to further investigations using XPS. Results showing the vibrational parameters and vibrationally resolved cross-sections and asymmetry parameters for N<sub>2</sub>O are presented together with theoretical predictions.</p>
120

Soft X-ray Scattering Dynamics Close to Core Ionization Thresholds in Atoms and Molecules

Söderström, Johan January 2007 (has links)
In this Thesis studies of highly excited states in gas-phase atoms and molecules (He, Ne, N2, O2, N2O and CO2) using a variety of synchrotron-radiation based techniques are presented. The three techniques used most frequently are X-ray-emission-threshold-electron coincidence (XETECO), X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) and they are all given a brief introduction. The fluorescence yield (FY) from doubly excited states in helium near the N=2 threshold(s) has been investigated in weak static external magnetic and electric fields, but also in a field free environment. The FY spectra in weak static magnetic fields show the importance of including the diamagnetic interaction in the theoretical models. The presence of weak static electric fields shows that even weak fields (as low as 44 V/cm) has a great impact on the observed FY spectra. Resonant XES spectra from some of the first doubly excited states in helium has been recorded in a field free environment, and compared to theory. The XETECO technique is presented and the first XETECO results from Ne, N2, O2, CO2 and N2O are shown, together with interpretations of possible threshold dynamics. I show that XETECO can be interpreted as threshold photoelectron spectra free from post collision interaction, and can hence be compared to above threshold XPS measurements. The observed below-threshold structures in the XETECO spectra are discussed and given a tentative explanation. The results from the analysis of the N2O XETECO spectrum lead to further investigations using XPS. Results showing the vibrational parameters and vibrationally resolved cross-sections and asymmetry parameters for N2O are presented together with theoretical predictions.

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