996 resultados para BALANCE CLOSURE PROBLEM
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Since the nineteenth century invention of adolescence, young people have been consistently identified as social problems in western societies. Their contemporary status as a focus of fear and anxiety is, in that sense, nothing new. In this paper, I try to combine this sense of historical recurrence about the youth problem with some questions about what is different about the present – asking what is distinctive about the shape of the youth problem now? This is a difficult balance to strike, and what I have to say will probably lean more towards an emphasis on the historical conditions and routes of the youth problem. That balance reflects my own orientations and knowledge (I am not expert on the contemporary conditions of being young). But it also arises from my belief that much contemporary social science is profoundly forgetful. An enthusiasm for stressing the newness, or novelty, of the present connects many varieties of contemporary scholarship. One result is the construction of what Janet Fink and I have referred to as ‘sociological time’ in which
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Domestic violence is a major public health problem, yet most physicians do not effectively identify patients at risk. Medical students and residents are not routinely educated on this topic and little is known about the factors that influence their decisions to include screening for domestic violence in their subsequent practice. In order to assess the readiness of primary care residents to screen all patients for domestic violence, this study utilized a survey incorporating constructs from the Transtheoretical Model, including Stages of Change, Decisional Balance (Pros and Cons) and Self-Efficacy. The survey was distributed to residents at the University of Texas Health Science Center Medical School in Houston in: Internal Medicine, Medicine/Pediatrics, Pediatrics, Family Medicine, and Obstetrics and Gynecology. Data from the survey was analyzed to test the hypothesis that residents in the earlier Stages of Change report more costs and fewer benefits with regards to screening for domestic violence, and that those in the later stages exhibit higher Self-Efficacy scores. The findings from this study were consistent with the model in that benefits to screening (Pros) and Self-Efficacy were correlated with later Stages of Change, however reporting fewer costs (Cons) was not. Very few residents were ready to screen all of their patients.^
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Background. Obesity is a major health problem throughout the industrialized world. Despite numerous attempts to curtail the rapid growth of obesity, its incidence continues to rise. Therefore, it is crucial to better understand the etiology of obesity beyond the concept of energy balance.^ Aims. The first aim of this study was to first investigate the relationship between eating behaviors and body size. The second goal was to identify genetic variation associated with eating behaviors. Thirdly, this study aimed to examine the joint relationships between eating behavior, body size and genetic variation.^ Methods. This study utilized baseline data ascertained in young adults from the Training Interventions and Genetics of Exercise (TIGER) Study. Variables assessed included eating behavior (Emotional Eating Scale, Eating Attitudes Test-26, and the Block98 Food Frequency Questionnaire), body size (body mass index, waist and hip circumference, waist/hip ratio, and percent body fat), genetic variation in genes implicated related to the hypothalamic control of energy balance, and appropriate covariates (age, gender, race/ethnicity, smoking status, and physical activity. For the genetic association analyses, genotypes were collapsed by minor allele frequency, and haplotypes were estimated for each gene. Additionally, Bayesian networks were constructed in order to determine the relationships between genetic variation, eating behavior and body size.^ Results. We report that the EAT-26 score, Caloric intake, percent fat, fiber intake, HEAT index, and daily servings of vegetables, meats, grains, and fats were significantly associated with at least one body size measure. Multiple SNPs in 17 genes and haplotypes from 12 genes were tested for their association with body size. Variation within both DRD4 and HTR2A was found to be associated with EAT-26 score. In addition, variation in the ghrelin gene (GHRL) was significantly associated with daily Caloric intake. A significant interaction between daily servings of grains and the HEAT index and variation within the leptin receptor gene (LEPR) was shown to influence body size.^ Conclusion. This study has shown that there is a substantial genetic component to eating behavior and that genetic variation interacts with eating behavior to influence body size.^
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Teen pregnancy is a continuing problem, bringing with it a host of associated health and social risks. Alternative school students are especially at risk, but are historically under-represented in research. This is especially problematic in that instruments are needed to guide effective intervention development, but psychometrics for these instruments cannot be assumed when used in new populations. Decisional balance from the transtheoretical model offers a framework for understanding condom decision making, but has not been tested with alternative school students. Using responses from 640 subjects from Safer Choices 2 (a school-based HIV/STD/pregnancy prevention program implemented in 10 urban, southwestern alternative schools), a decisional balance scale for condom use was examined. A two-factor, mildly correlated model fit the data well. Tests of invariance examined scale functioning within gender and racial/ethnic groups. The underlying structure varied slightly based on subgroup, but on a practical level the impact on the use of scales was minimal. The structure and loadings were invariant across experimental condition. The pro scale was associated with a lower probability of having engaged in unprotected sexual behavior for sexually active subjects, and this association remained significant while controlling for demographic variables. The con scale did not show a significant association with engagement in unprotected sexual behaviors. Limitations and directions for future research were also discussed.^
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A mathematical formulation for finite strain elasto plastic consolidation of fully saturated soil media is presented. Strong and weak forms of the boundary-value problem are derived using both the material and spatial descriptions. The algorithmic treatment of finite strain elastoplasticity for the solid phase is based on multiplicative decomposition and is coupled with the algorithm for fluid flow via the Kirchhoff pore water pressure. Balance laws are written for the soil-water mixture following the motion of the soil matrix alone. It is shown that the motion of the fluid phase only affects the Jacobian of the solid phase motion, and therefore can be characterized completely by the motion of the soil matrix. Furthermore, it is shown from energy balance consideration that the effective, or intergranular, stress is the appropriate measure of stress for describing the constitutive response of the soil skeleton since it absorbs all the strain energy generated in the saturated soil-water mixture. Finally, it is shown that the mathematical model is amenable to consistent linearization, and that explicit expressions for the consistent tangent operators can be derived for use in numerical solutions such as those based on the finite element method.
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El objetivo de ésta tesis es estudiar cómo desarrollar una aplicación informática que implemente algoritmos numéricos de evaluación de características hidrodinámicas de modelos geométricos representativos de carenas de buques. Se trata de especificar los requisitos necesarios que debe cumplir un programa para informático orientado a dar solución a un determinado problema hidródinámico, como es simular el comportamiento en balance de un buque sometido a oleaje, de popa o proa. una vez especificada la aplicación se realizará un diseño del programa; se estudiarán alternativas para implementar la aplicación; se explicará el proceso que ha de seguirse para obtener la aplicación en funcionamiento y se contrastarán los resultados obtenidos en la medida que sea posible. Se pretende sistematizar y sintetizar todo el proceso de desarrollo de software, orientado a la simulación del comportamiento hidrodinámico de un buque, en una metodología que se pondrá a disposición de la comunidad académica y científica en la forma que se considere más adecuada. Se trata, por tanto, de proponer una metodología de desarrollo de software para obetener una aplicación que facilite la evaluación de diferentes alternativas de estudio variando parámetros relativos al problema en estudio y que sea capaz de proporcionar resultados para su análisis. Así mismo se incide en cómo ha de conducirse en el proceso para que dicha aplicación pueda crecer, incorporando soluciones existentes no implementadas o nuevas soluciones que aparezcan en este ámbito de conocimiento. Como aplicación concreta de la aplicación se ha elegido implementar los algoritmos necesarios para evaluar la aparición del balance paramétrico en un buque. En el análisis de éste problema se considera de interés la representación geométrica que se hace de la carena del buque. Además de la carena aparecen otros elementos que tienen influencia determinante en éste estudio, como son las situación de mar y las situaciones de carga. Idealmente, el problema sería resuelto si se consiguiera determinar el ángulo de balance que se produce al enfrentar un buque a las diferentes condiciones de mar. Se pretende preparar un programa utilizando el paradigma de la orientación a objetos. Considero que es la más adecuada forma de modularizar el programa para poder utilizar diferentes modelos de una misma carena y así comparar los resultados de la evaluación del balance paramétrico entre sí. En una etapa posterior se podrían comparar los resultados con otros obtenidos empíricamente. Hablo de una nueva metodología porque pretendo indicar cómo se ha de construir una aplicación de software que sea usable y sobre la que se pueda seguir desarrollando. Esto justifica la selección del lenguaje de programación C++. Se seleccionará un núcleo geométrico de software que permita acoplar de forma versátil los distintos componentes de software que van a construir el programa. Este trabajo pretende aplicar el desarrollo de software a un aspecto concreto del área de conocimiento de la hidrodinámica. No se pretende aportar nuevos algoritmos para resolver problemas de hidrodinámica, sino diseñar un conjunto de objetos de software que implementen soluciones existentes a conocidas soluciones numéricas a dichos problemas. Se trata fundamentalmente de un trabajo de software, más que de hidrodinámica. Lo que aporta de novedad es una nueva forma de realizar un programa aplicado a los cálculos hidrodinámicos relativos a la determinación del balance paramétrico, que pueda crecer e incorporar cualquier novedad que pueda surgir más adelante. Esto será posible por la programación modular utilizada y los objetos que representan cada uno de los elementos que intervienen en la determinación del balance paramétrico. La elección de aplicar la metodología a la predicción del balance paramétrico se debe a que este concepto es uno de los elementos que intervienen en la evaluación de criterios de estabilidad de segunda generación que estan en estudio para su futura aplicación en el ámbito de la construcción naval. Es por tanto un estudio que despierta interés por su próxima utilidad. ABSTRACT The aim of this thesis is to study how to develop a computer application implementing numerical algorithms to assess hydrodynamic features of geometrical models of vessels. It is therefore to propose a methodology for software development applied to an hydrodynamic problem, in order to evaluate different study alternatives by varying different parameters related to the problem and to be capable of providing results for analysis. As a concrete application of the program it has been chosen to implement the algorithms necessary for evaluating the appearance of parametric rolling in a vessel. In the analysis of this problem it is considered of interest the geometrical representation of the hull of the ship and other elements which have decisive influence in this phenomena, such as the sea situation and the loading condition. Ideally, the application would determine the roll angle that occurs when a ship is on waves of different characteristics. It aims to prepare a program by using the paradigm of object oriented programming. I think it is the best methodology to modularize the program. My intention is to show how face the global process of developing an application from the initial specification until the final release of the program. The process will keep in mind the spefici objetives of usability and the possibility of growing in the scope of the software. This work intends to apply software development to a particular aspect the area of knowledge of hydrodynamics. It is not intended to provide new algorithms for solving problems of hydrodynamics, but designing a set of software objects that implement existing solutions to these problems. This is essentially a job software rather than hydrodynamic. The novelty of this thesis stands in this work focuses in describing how to apply the whole proccess of software engineering to hydrodinamics problems. The choice of the prediction of parametric balance as the main objetive to be applied to is because this concept is one of the elements involved in the evaluation of the intact stability criteria of second generation. Therefore, I consider this study as relevant usefull for the future application in the field of shipbuilding.
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The role of the abundant stress protein Hsp90 in protecting cells against stress-induced damage is not well understood. The recent discovery that a class of ansamycin antibiotics bind specifically to Hsp90 allowed us to address this problem from a new angle. We find that mammalian Hsp90, in cooperation with Hsp70, p60, and other factors, mediates the ATP-dependent refolding of heat-denatured proteins, such as firefly luciferase. Failure to refold results in proteolysis. The ansamycins inhibit refolding, both in vivo and in a cell extract, by preventing normal dissociation of Hsp90 from luciferase, causing its enhanced degradation. This mechanism also explains the ansamycin-induced proteolysis of several protooncogenic protein kinases, such as Raf-1, which interact with Hsp90. We propose that Hsp90 is part of a quality control system that facilitates protein refolding or degradation during recovery from stress. This function is used by a limited set of signal transduction molecules for their folding and regulation under nonstress conditions. The ansamycins shift the mode of Hsp90 from refolding to degradation, and this effect is probably amplified for specific Hsp90 substrates.
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Azerbaijan’s cooperation with the West, launched two decades ago, has helped it become a relatively strong and ambitious actor on the international stage. It has become a key country in the region from the Western (USA and the EU) and Turkish points of view, as well as an important partner in the energy sector. The strategic EU concept of the Southern Gas Corridor, also supported by the United States, is among the initiatives based on cooperation with Azerbaijan. Surprisingly, however, Azerbaijan’s increased ambition and importance have caused its policy to diverge ever farther from the expectations and plans formulated by the West. The changes in the balance of power in the South Caucasus, occurring in the context of the conflict in Ukraine, have forced Azerbaijan to revise its assessment of its position in the region. The main impetus for Azerbaijan’s actions is fear of Russia, as well as the weakness of the West which has become particularly apparent in the recent stages of the Ukrainian crisis. Azerbaijan’s actions so far have displayed its tendency to deepen its self-isolation in foreign affairs and consolidate its authoritarian system. This comes as a challenge to the West, whose ability to shape its relations with Azerbaijan has weakened considerably. This state of affairs poses the threat that in the current situation, the Southern Gas Corridor concept, which Azerbaijan amended in 2012 in its own favour, might become totally blocked.
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Creativity is increasingly recognised as an essential component of engineering design. This paper describes an exploratory study into the nature and importance of creativity in engineering design problem solving in relation to the possible impact of software design tools. The first stage of the study involved an empirical investigation in the form of a case study of the use of standard CAD tool sets and the development of a systems engineering software support tool. It was found that there were several ways in which CAD influenced the creative process, including enhancing visualisation and communication, premature fixation, circumscribed thinking and bounded ideation. The tool development experience uncovered the difficulty in supporting creative processes from the developer's perspective. The issues were the necessity of making assumptions, achieving a balance between structure and flexibility, and the pitfalls of satisfying user wants and needs. The second part of the study involved the development of a model of the creative problem solving process in engineering design. This provided a possible explanation for why purpose designed engineering software tools might encourage an analytical problem solving approach and discourage a more creative approach.
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The aim of this thesis is to critically examine drug prevention as a field of problematizations – how drug prevention becomes established as a political technology within this field, how it connects to certain modes of governance, how and under which conditions it constitutes it’s problematic, the questions it asks, it´s implications in terms of political participation and representation, the various bodies of knowledge through which it constitutes the reality upon which it acts, the limits it places on ways of being, questioning, and talking in the world. The main analyses have been conducted in four separate but interrelated articles. Each article addresses a specific dimension of drug prevention in order to get a grasp of how this field is organized. Article 1 examines the shift that has occurred in the Swedish context during the period 1981–2011 in how drugs have been problematized, what knowledge has grounded the specific modes of problematization and which modes of governance this has enabled. In article 2, the currently dominant scientific discipline in the field of drug prevention – prevention science – is critically examined in terms of how it constructs the “drug problem” and the underlying assumptions it carries in regard to reality and political governance. Article 3 addresses the issue of communities’ democratic participation in drug prevention efforts by analyzing the theoretical foundations of the Communities That Care prevention program. The article seeks to uncover how notions of community empowerment and democratic participation are constructed, and how the “community” is established as a political entity in the program. The fourth and final article critically examines the Swedish Social and Emotional Training (SET) program and the political implications of the relationship the program establishes between the subject and emotions. The argument is made that, within the field of drug prevention, questions of political values and priorities in a problematic way are decoupled from the political field and pose a significant problem in terms of the possibilities to engage in democratic deliberation. Within this field of problematizations it becomes impossible to mobilize a politics against social injustice, poverty and inequality. At the same time, the scientific grounding of this mode of governing the drug “problem” acts to naturalize a specific – highly political – way of engaging with drugs.
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This paper examines how the loss of 6300 jobs from the closure of MG Rover (MGR) in the city of Birmingham (UK) in April 2005 affected the employment trajectories of ex-workers, in the context of wider structural change and efforts at urban renewal. The paper presents an analysis of a longitudinal survey of 300 ex-MGR workers, and examines to what extent the state of local labour markets and workers’ geographical mobility—as well as the effectiveness of the immediate policy response and longer-term local economic strategies—may have helped to balance the impacts of personal attributes associated with workers’ employability and their reabsorption into the labour markets. It is found that the relative buoyancy of the local economy, the success of longer-run efforts at diversification and a strong policy response and retraining initiative helped many disadvantaged workers to find new jobs in the medium term. However, the paper also highlights the unequal employment outcomes and trajectories that many lesser-skilled workers faced. It explores the policy issues arising from such closures and their aftermath, such as the need to co-ordinate responses, to retain institutional capacity, to offer high-quality training and education resources to workers and, where possible, to slow down such closure processes to enable skills to be retained and reused within the local economy.
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The world food crisis, Britain's reliance on imported food and feedstuffs and balance of payments difficulties were some of the factors which lent weight to the call for increased self-sufficiency in Britain's agriculture in the 1970s. This project considers two main areas: an investigation of the impact of radical agricultural change, designed to increase self-sufficiency, on the balance of payments; and, an appraisal of the potential role of the food industry within a radically different food system. The study proceeded by: an examination of the principles of agricultural policy and its development in Britain; an overview of the mechanism and meaning of the balance of payments; a consideration of the debate on agricultural import saving; the construction of radical agricultural strategies; the estimation of effects of the strategies, particularly to the balance of. payments; the role of the food industry and possible innovations within the strategies; a case study of textured vegetable proteins; and, the wider implications of implementation of radical agricultural alternatives. Two strategies were considered: a vegan system, involving no livestock; and, an intermediate system, including some livestock and dairy cattle. The study concludes that although agricultural change could in principle make a contribution to the balance of payments, implementation of agricultural change cannot be justified for this purpose alone. First, balance of payments problems can be solved by more appropriate methods. Second, the UK' s balance of payments problem has disappeared for the time being owing to North Sea oil and economic recession. Third, the political and social consequences of the changes investigated would be unacceptable. Progress in UK food policy is likely to be in the form of an integrated food and health policy.
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Two assembly line balancing problems are addressed. The first problem (called SALBP-1) is to minimize number of linearly ordered stations for processing n partially ordered operations V = {1, 2, ..., n} within the fixed cycle time c. The second problem (called SALBP-2) is to minimize cycle time for processing partially ordered operations V on the fixed set of m linearly ordered stations. The processing time ti of each operation i ∈V is known before solving problems SALBP-1 and SALBP-2. However, during the life cycle of the assembly line the values ti are definitely fixed only for the subset of automated operations V\V . Another subset V ⊆ V includes manual operations, for which it is impossible to fix exact processing times during the whole life cycle of the assembly line. If j ∈V , then operation times tj can differ for different cycles of the production process. For the optimal line balance b of the assembly line with operation times t1, t2, ..., tn, we investigate stability of its optimality with respect to possible variations of the processing times tj of the manual operations j ∈ V .
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2000 Mathematics Subject Classification: 62K05, 05B05.
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The delta18O values of planktonic foraminifera increased in the Caribbean by about 0.5? relative to the equatorial East Pacific values between 4.6 and 4.2 Ma as a consequence of the closure of the Central American Gateway (CAG). This increase in delta18O can be interpreted either as an increase in Caribbean sea surface (mixed layer) salinity (SSS) or as a decrease in sea surface temperatures (SST). This problem represents an ideal situation to apply the recently developed paleotemperature proxy delta44/40Ca together with Mg/Ca and d18O on the planktic foraminifer Globigerinoides sacculifer from ODP Site 999. Although differences in absolute temperature calibration of delta44/40Ca and Mg/Ca exist, the general pattern is similar indicating a SST decrease of about 2-3 8C between 4.4 and 4.3 Ma followed by an increase in the same order of magnitude between 4.3 and 4.0 Ma. Correcting the delta18O record for this temperature change and assuming that changes in global ice volume are negligible, the salinity-induced planktonic delta18O signal decreased by about 0.4? between 4.4 and 4.3 Ma and increased by about 0.9? between 4.3 and 4.0 Ma in the Caribbean. The observed temperature and salinity trends are interpreted to reflect the restricted exchange of surface water between the Caribbean and the Pacific in response to the shoaling of the Panamanian Seaway, possibly accompanied by a southward shift of the Intertropical Convergence Zone (ITCZ) between 4.4 and 4.3 Ma. Differences in Mg/Ca- and delta44/40Ca-derived temperatures can be reconciled by corrections for secular variations of the marine Mg/Ca[sw] and delta44/40Ca, a salinity effect on the Mg/Ca ratio and a constant temperature offset of ~2.5 °C between both SST proxy calibrations.