Esta tese é dedicada ao estudo de uma classe de equações de ondas com condições de fronteira da acústica. Investigamos a dinâmica assintótica de tais equações no caso em que o sistema está sujeito à ação de uma força externa não autônoma. Nessa situação, adicionando uma dissipação fraca, provamos que o problema gera um processo de evolução dissipativo. O nosso objetivo é então o estudo da existência de atratores não autônomos. Num primeiro momento estabelecemos a existência de um atrator do tipo \\pullback\", minimal, dentro de um universo de conjuntos temperados. Também estudamos a semicontinuidade superior dos atratores quando a perturbação não autônoma tende para zero. Nosso resultado permite considerar forcas externas não limitadas e perturbações não lineares com crescimento crítico (de Sobolev). Num segundo momento, fazemos um estudo sobre a existência de atratores uniformes. Em vista de resultados recentes de Zelik (2015), consideramos forcas externas mais gerais do que a dita classe das forcas compactas por translação (translation-compact). Parte desta tese foi aceita para publicação na revista \\Differential and Integral Equations\" sob o ttulo \\Pullback dynamics of non-autonomous wave equations with acoustic boundary condition\". / This thesis is concerned with the study of a class of wave equations with acoustic boundary conditions. We investigate the long-time dynamics of such equations in the case where the system is subject to a non-autonomous external force. In this situation, by adding a weak dissipation, we prove that the problem generates a dissipative evolution process. Our goal is then the existence of non-autonomous attractors. In this direction, we first establishes the existence of a minimal pullback attractor within a universe of tempered sets. We also studied the upper semi-continuity of attractors when the non-autonomous perturbation tends to zero. Our result allows to consider unbounded external forces and nonlinear perturbation with critical (Sobolev) growth. Secondly, we establish the existence of uniform attractors, as well. In view of recent results Zelik (2015) we consider more general external forces than the so called class of translation-compact forces. Part of this thesis was accepted for publication in the journal \\Differential and Integral Equations\" under the title \\Pullback dynamics of non-autonomous wave equations with acoustic boundary condition\".

A visão de cores apresenta um papel muito importante para a sobrevivência e desenvolvimento de primatas. A capacidade de discriminar, visualmente, o alvo de um fundo apenas pela diferença de matiz pode ser o diferencial tanto para a busca de alimentos, como para a fuga de predadores. Estudos sobre a visão de cores auxiliam a fazer inferências sobre suas bases biológicas e utilidade funcional. O presente estudo buscou avaliar a discriminação de cores em primatas do gênero Alouatta (Bugio), por meio de uma adaptação do teste computadorizado Cambridge Colour Test (CCT) e do sequenciamento dos genes que codificam as opsinas, uma vez que por estudos anteriores inferia-se que eles pudessem apresentar visão tricromática, diferenciando-os dos outros platirrinos. Para este estudo foram utilizados 6 indivíduos do Centro Nacional de Primatas (CENP, Ananindeua, Pará, Brasil). O experimento comportamental objetivava determinar elipses de discriminação de cor para três fundos de diferentes cromaticidades do diagrama CIE 1976 uv, as quais serviram de parâmetro para a determinação do fenótipo dos indivíduos. A análise genética buscou identificar as variedades de opsinas. Dois indivíduos concluíram o teste comportamental com sucesso, um macho de Alouatta caraya e uma fêmea de Alouatta seniculus, ambos apresentando visão de cores tricromática. A análise molecular identificou a presença de dois alelos para comprimentos médios/longos da opsina. O potencial de tricromacia demonstrado na análise genética foi compatível com os resultados da análise comportamental que mostraram capacidade discriminativa tricromática. Neste trabalho abordamos os diversos aspectos desse estudo, tanto na modelagem dos animais quanto na importância desse achado / Color vision has a very important role in the survival and development of primates. The ability to visually discriminate the target of a background only by hue difference may be the difference for both search of food or escape from predators. Studies on color vision help to make inferences about their biological bases and functional utility. This study sought to evaluate the color discrimination in primates of the genus Alouatta (Howler monkey), through an adaptation of the computerized test Cambridge Colour Test (CCT) and the sequencing of the genes coding opsins. Through previous studies have inferred that they could present trichromatic vision, distinguishing them from other platyrrhines. Six subjects from the National Primate Center (CENP, Ananindeua, Pará, Brazil) were tested. The behavioral experiment aimed to determine color discrimination ellipses to three backgrounds of different chromaticity at CIE 1976 u\'v\' diagram, which served as a parameter for determining the phenotype of individuals and the genetic analysis sought to identify the varieties of opsins. Two individuals completed the test successfully one male and one female, both featuring trichromatic color vision. Two individuals successfully completed the behavioral test, one Alouatta caraya male and one Alouatta seniculus female, both presenting trichromatic color vision. Molecular analysis identified the presence of two alleles for medium/long lengths of opsin compatible with behavioral analysis. In this work we approach the various aspects of this study, both in the modeling of the animals and in the importance of this finding

A controlled continuous laser output using a circular geometry with a gaussian intensity distribution was used to harden the surface of a particular metal specimen (44MnSiVS6). Said beam operated within a relatively small power interval, just barely past the melting point. The resulting martensite track was shown to expand laterally at a positive exponential rate, with respect to the energy input. This was furthermore accompanied with an increase of the average slope at each lateral edge. The thickness was seen to expand at a significantly slower rate (by about one order of magnitude), with declining efficiency in regard to the energy input used. Thermal measurements along the surface indicated somewhat uniform temperature patterns within a relatively large area surrounding the middle of the beam spot. Though a slight elevation in temperature was often noted in the vicinity of its centre. In addition to using a gaussian beam, three other intensity distributions were utilized. The results obtained from said distributions may suggest effectual alterations to occur in terms of the shape and extent of the resulting martensite zone, if the spread of the gaussian intensity profile is allowed to be modified. Ideally, this would be carried out while still remaining close to the melting point, as well as keeping the spot size unchanged. A series of vicker's hardness measurements was carried out for each track induced by a different beam distribution. A clear transition in hardness was noted across the perceived boundary between the martensite zone and the base material, confirming the legitimacy regarding the phase identification. / Stiffcrank - Advanced laser surface hardening of microalloyed steels for fatigue enhancement of automotive engine components, funded by EU-RFCS, no. 754155

<p>The aim of this thesis was to study the strategies that Kamraterna (‘the Comrades’), an association for Stockholm’s policemen, and the Swedish Policemen’s Union employed in order to solve the issue of women in police service in the years 1957-1971. I have dealt with the attitudes they had to women in police service and the conceptions of gender that were expressed. The trade unions’ way of trying to solve the issue of women’s service and position in the organisation and Kamraterna’s actions vis-à-vis their female members have also been in focus. Finally, I have also studied the way in which the police profession was made masculine and feminine and how this could be used as a part of the strategies. </p><p>Women’s entrance into the police profession on the same terms as men created and made visible the gender structures in the police force. The male police officers saw their rights threatened, if the female labour could be judged differently and hence be promoted more rapidly. This conflict made conceptions of male and female qualities visible, and above all in Kamraterna, a struggle was started to maintain male police officers’ privileges and rights. </p><p>The unions emphasised that women would have to be employed on equal terms and that equal pay must imply equal work. Women were however considered to be best suited for social police work and work with women and children, while men were chiefly associated with the parts of the profession involving physical strength and violence. It was difficult to implement the principle of equal terms in practice, since there was a basic idea that women were different. Both Kamraterna and the Swedish Policemen’s Union used dual closure in order to solve this dilemma. Kamraterna’s usurpation was intended to influence the police commissioner and to unite the members, including the women, thereby creating a collective unity about the issue of the female police officers’ posts and work. They tried to remove the women from foot patrol work by having them relocated to other departments with civil duties. In this way they endeavoured to keep the patrol work as an exclusively male area by resorting to exclusion. When the National Police Board started experimental work in 1969 with female police officers being stationed in special units with civil duties, the Swedish Policemen’s Union supported this effort and tried to see to it that the instructions were followed. The Policemen’s Union thus employed exclusion. Excluding women from parts of the profession meant that the unions used a demarcationary strategy resulting in a gendered division of labour being created rather than the women being entirely excluded from the police profession. The patrol work was the part of the police profession that women ought not to have access to, and this was linked to masculine qualities and symbolism. Words like physical strength, strenuous service and violence were related to the patrol work. The uniforms and weapons underscored the masculine connotations of the patrol work. A hegemonic masculinity was created here, which could be used as a means for excluding female police officers. The women’s uniforms looked different and their weapons were not the same, which should have made it more difficult for them to be regarded as real police officers. </p>

The aim of this thesis was to study the strategies that Kamraterna (‘the Comrades’), an association for Stockholm’s policemen, and the Swedish Policemen’s Union employed in order to solve the issue of women in police service in the years 1957-1971. I have dealt with the attitudes they had to women in police service and the conceptions of gender that were expressed. The trade unions’ way of trying to solve the issue of women’s service and position in the organisation and Kamraterna’s actions vis-à-vis their female members have also been in focus. Finally, I have also studied the way in which the police profession was made masculine and feminine and how this could be used as a part of the strategies. Women’s entrance into the police profession on the same terms as men created and made visible the gender structures in the police force. The male police officers saw their rights threatened, if the female labour could be judged differently and hence be promoted more rapidly. This conflict made conceptions of male and female qualities visible, and above all in Kamraterna, a struggle was started to maintain male police officers’ privileges and rights. The unions emphasised that women would have to be employed on equal terms and that equal pay must imply equal work. Women were however considered to be best suited for social police work and work with women and children, while men were chiefly associated with the parts of the profession involving physical strength and violence. It was difficult to implement the principle of equal terms in practice, since there was a basic idea that women were different. Both Kamraterna and the Swedish Policemen’s Union used dual closure in order to solve this dilemma. Kamraterna’s usurpation was intended to influence the police commissioner and to unite the members, including the women, thereby creating a collective unity about the issue of the female police officers’ posts and work. They tried to remove the women from foot patrol work by having them relocated to other departments with civil duties. In this way they endeavoured to keep the patrol work as an exclusively male area by resorting to exclusion. When the National Police Board started experimental work in 1969 with female police officers being stationed in special units with civil duties, the Swedish Policemen’s Union supported this effort and tried to see to it that the instructions were followed. The Policemen’s Union thus employed exclusion. Excluding women from parts of the profession meant that the unions used a demarcationary strategy resulting in a gendered division of labour being created rather than the women being entirely excluded from the police profession. The patrol work was the part of the police profession that women ought not to have access to, and this was linked to masculine qualities and symbolism. Words like physical strength, strenuous service and violence were related to the patrol work. The uniforms and weapons underscored the masculine connotations of the patrol work. A hegemonic masculinity was created here, which could be used as a means for excluding female police officers. The women’s uniforms looked different and their weapons were not the same, which should have made it more difficult for them to be regarded as real police officers.

This dissertation served two purposes. The first was to develop a method of detecting differential item functioning (DIF) within tests containing both dichotomously and polytomously scored items. The second was related to gender and aimed a) to investigate if those items that were functioning differently for girls and boys showed any characteristic properties and, if so, b) determine if these properties could be used to predict which items would be flagged for D1F. The method development was based on the Mantel-Haenszel (MH) method used for dichotmously scored items. By dichotomizing the polytomously scored items both types of item could be compared on the same statistical level as either solved or non-solved items. It was not possible to compare the internal score structures for the two gender groups, only overall score differences were detected. By modelling the empirical item characteristic curves it was possible to develop a MH method for identifying nonuniform DIF. Both internal and external ability criteria were used. Total test score with no purification was used as the internal criterion. Purification was not done for validity reasons, no items were judged as biased. Teacher set marks were used as external criteria. The marking scale had to be transformed for either boys or girls since a comparison of scores for boys and girls with the same marks showed that boys always got higher mean scores. The results of the two MH analyses based on internal and external criterion were compared with results from P-SIBTEST. All three methods corresponded well although P-SIBTEST flagged considerably more items in favour of the reference group (boys) which exhibited a higher overall ability. All 200 items included in the last 15 annual national tests in physics were analysed for DIF and classified by ten criteria The most significant result was that items in electricity were, to a significantly higher degree, flagged as DIF in favour of girls whilst items in mechanics were flagged in favour of boys. Items in other content areas showed no significant pattern. Multiple-Choice items were flagged in favour of boys. Regardless of the degree of significance by which items from different content areas were flagged on a group level it was not possible to predict which single item would be flagged for DIF. The most probable prediction was always that an item was neutral. Some possible interpretations of DIF as an effect of multidimen-sionality were discussed as were some hypotheses about the reasons why boys did better in mechanics and girls in electricity. / digitalisering@umu

This thesis deals with random-size subset selection and ranking procedures• • • )|(derived through likelihood ratios, mainly in terms of the P -approach.Let IT , . .. , IT, be k(&gt; 2) populations such that IR.(i = l, . . . , k) hasJ_ K. — 12the normal distribution with unknwon mean 0. and variance a.a , where a.i i i2 . . is known and a may be unknown; and that a random sample of size n^ istaken from . To begin with, we give procedure (with tables) whichselects IT. if sup L(0;x) &gt;c SUD L(0;X), where SÎ is the parameter space1for 0 = (0-^, 0^) ; where (with c: ß) is the set of all 0 with0. = max 0.; where L(*;x) is the likelihood function based on the total1sample; and where c is the largest constant that makes the rule satisfy theP*-condition. Then, we consider other likelihood ratios, with intuitivelyreasonable subspaces of ß, and derive several new rules. Comparisons amongsome of these rules and rule R of Gupta (1956, 1965) are made using differentcriteria; numerical for k=3, and a Monte-Carlo study for k=10.For the case when the populations have the uniform (0,0^) distributions,and we have unequal sample sizes, we consider selection for the populationwith min 0.. Comparisons with Barr and Rizvi (1966) are made. Generalizai&lt;j&lt;k Jtions are given.Rule R^ is generalized to densities satisfying some reasonable assumptions(mainly unimodality of the likelihood, and monotonicity of the likelihoodratio). An exponential class is considered, and the results are exemplifiedby the gamma density and the Laplace density. Extensions and generalizationsto cover the selection of the t best populations (using various requirements)are given. Finally, a discussion oil the complete ranking problem,and on the relation between subset selection based on likelihood ratios andstatistical inference under order restrictions, is given. / digitalisering@umu

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.

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.

Next generation data centres are expected to support both advance resource reservation and on-demand access, but the system performance for such a computing environment has not been well-investigated. A reservation request is characterized by a start time, duration, and resource requirement. Discrete event simulation is used to study the performance characteristics of reservation systems. The basic strategy is to accept a request if resources are available and reject the request otherwise. The performance metrics considered are resource utilization and blocking probability. Results showing the impact of input parameters on these performance metrics are presented. It is found that the resource utilization is quite low. Two strategies that can be used to improve the performance for advance reservation are evaluated. The first strategy allows the start time to be delayed up to some maximum value, while the second allows the possibility of non-uniform resource allocation over the duration of the reservation. Simulation results showing the performance improvements of these two strategies are presented. Resources not used by advance reservation are used to support on-demand access. The performance metrics of interest is the mean response time. Simulation results showing the impact of resource availability and its variation over time on the mean response time are presented. These results provide valuable insights into the performance of systems with time-varying processing capacity. They can also be used to develop guidelines for the non-uniform resource allocation strategy for advance reservation in case the reserved resources are used for interactive access.