891 resultados para One-Way Function (OWF)


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Objectives This study established the value of the 6-sulfatoxymelatonin (aMT6s) urine concentration as a predictor of the therapeutic response to noradrenaline reuptake inhibitors in depressive patients. Methods Twenty-two women aged 18-60 years were selected. Depressive symptoms were assessed by using the Hamilton Depression Scale. Urine samples were collected at 0600-1200 h, 1200-1800 h, 1800-2400 h, and 2400-0600 h intervals, 1 day before and 1 day after starting on the nortriptyline treatment. Urine aMT6s concentration was analyzed by a one-way analysis of variance/Bonferroni test. Spearman`s rank correlation coefficient was used to analyze the correlation between depressive symptoms after 2 weeks of antidepressant treatment and the increase in aMT6s urine concentration. Results Higher and lower size effect groups were compared by independent Student`s t-tests. At baseline, the 2400- to 0600-h interval differed from all other intervals presenting a significantly higher aMT6s urine concentration. A significant difference in aMT6s urine concentrations was found 1 day after treatment in all four intervals. Higher size effect group had lower levels of depressive symptoms 2 weeks after the treatment. A positive correlation between depressive symptoms and the delta of aMT6s in the 2400-0600h interval was observed. Conclusion Our results reinforce the hypothesis that aMT6s excretion is a predictor of clinical outcome in depression, especially in regard to noradrenaline reuptake inhibitors. Copyright (C) 2011 John Wiley & Sons, Ltd.

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Complex networks obtained from real-world networks are often characterized by incompleteness and noise, consequences of imperfect sampling as well as artifacts in the acquisition process. Because the characterization, analysis and modeling of complex systems underlain by complex networks are critically affected by the quality and completeness of the respective initial structures, it becomes imperative to devise methodologies for identifying and quantifying the effects of the sampling on the network structure. One way to evaluate these effects is through an analysis of the sensitivity of complex network measurements to perturbations in the topology of the network. In this paper, measurement sensibility is quantified in terms of the relative entropy of the respective distributions. Three particularly important kinds of progressive perturbations to the network are considered, namely, edge suppression, addition and rewiring. The measurements allowing the best balance of stability (smaller sensitivity to perturbations) and discriminability (separation between different network topologies) are identified with respect to each type of perturbation. Such an analysis includes eight different measurements applied on six different complex networks models and three real-world networks. This approach allows one to choose the appropriate measurements in order to obtain accurate results for networks where sampling bias cannot be avoided-a very frequent situation in research on complex networks.

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The aim of task scheduling is to minimize the makespan of applications, exploiting the best possible way to use shared resources. Applications have requirements which call for customized environments for their execution. One way to provide such environments is to use virtualization on demand. This paper presents two schedulers based on integer linear programming which schedule virtual machines (VMs) in grid resources and tasks on these VMs. The schedulers differ from previous work by the joint scheduling of tasks and VMs and by considering the impact of the available bandwidth on the quality of the schedule. Experiments show the efficacy of the schedulers in scenarios with different network configurations.

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Coconut water is a natural isotonic, nutritive, and low-caloric drink. Preservation process is necessary to increase its shelf life outside the fruit and to improve commercialization. However, the influence of the conservation processes, antioxidant addition, maturation time, and soil where coconut is cultivated on the chemical composition of coconut water has had few arguments and studies. For these reasons, an evaluation of coconut waters (unprocessed and processed) was carried out using Ca, Cu, Fe, K, Mg, Mn, Na, Zn, chloride, sulfate, phosphate, malate, and ascorbate concentrations and chemometric tools. The quantitative determinations were performed by electrothermal atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and capillary electrophoresis. The results showed that Ca, K, and Zn concentrations did not present significant alterations between the samples. The ranges of Cu, Fe, Mg, Mn, PO (4) (3-) , and SO (4) (2-) concentrations were as follows: Cu (3.1-120 A mu g L(-1)), Fe (60-330 A mu g L(-1)), Mg (48-123 mg L(-1)), Mn (0.4-4.0 mg L(-1)), PO (4) (3-) (55-212 mg L(-1)), and SO (4) (2-) (19-136 mg L(-1)). The principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to differentiate unprocessed and processed samples. Multivariated analysis (PCA and HCA) were compared through one-way analysis of variance with Tukey-Kramer multiple comparisons test, and p values less than 0.05 were considered to be significant.

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Librarians must continue their traditional roles as privacy rights activists and intellectual freedom upholders into the digital age, and across electronic information sources, including social media fora. Social media is quickly becoming a major source of information and center for information seeking, and librarians have an opportunity to promote and help shape social media policies that protect users’ privacy and assure that users can seek information without inhibition. One way librarians can be involved in the promotion of online privacy is by joining the social media user rights movement and advocating terms of use agreements that protect information seekers that follow the "Privacy by Design" model created by Ann Cavoukian, Ph.D.

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Since last two decades researches have been working on developing systems that can assistsdrivers in the best way possible and make driving safe. Computer vision has played a crucialpart in design of these systems. With the introduction of vision techniques variousautonomous and robust real-time traffic automation systems have been designed such asTraffic monitoring, Traffic related parameter estimation and intelligent vehicles. Among theseautomatic detection and recognition of road signs has became an interesting research topic.The system can assist drivers about signs they don’t recognize before passing them.Aim of this research project is to present an Intelligent Road Sign Recognition System basedon state-of-the-art technique, the Support Vector Machine. The project is an extension to thework done at ITS research Platform at Dalarna University [25]. Focus of this research work ison the recognition of road signs under analysis. When classifying an image its location, sizeand orientation in the image plane are its irrelevant features and one way to get rid of thisambiguity is to extract those features which are invariant under the above mentionedtransformation. These invariant features are then used in Support Vector Machine forclassification. Support Vector Machine is a supervised learning machine that solves problemin higher dimension with the help of Kernel functions and is best know for classificationproblems.

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Today, there are no standardized ways to characterize SOA, many are talking about SOA and many say they are using SOA. One way that we have chosen to characterize this phenomenon is through an evaluation that will indicate whether SOA have been used in the development. Basedon a Service Oriented Architecture literature study, we have created an evaluation pattern resulting SOA principles of integration, architecture and services. This evaluation was applied to Logica's own integration system AgrCom through an empirical study to result in a response indicating whether AgrCom is SOA based. The results of the evaluation show that AgrCom is part of an SOA solution but not an SOA as a whole concept. The study shows that it takes morethan just systems in an activity to be referred to as the SOA-based, hence the architecture of anactivity must be taken into account.

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In a northern European climate a typical solar combisystem for a single family house normally saves between 10 and 30 % of the auxiliary energy needed for space heating and domestic water heating. It is considered uneconomical to dimension systems for higher energy savings. Overheating problems may also occur. One way of avoiding these problems is to use a collector that is designed so that it has a low optical efficiency in summer, when the solar elevation is high and the load is small, and a high optical efficiency in early spring and late fall when the solar elevation is low and the load is large.The study investigates the possibilities to design the system and, in particular, the collector optics, in order to match the system performance with the yearly variations of the heating load and the solar irradiation. It seems possible to design practically viable load adapted collectors, and to use them for whole roofs ( 40 m2) without causing more overheating stress on the system than with a standard 10 m2 system. The load adapted collectors collect roughly as much energy per unit area as flat plate collectors, but they may be produced at a lower cost due to lower material costs. There is an additional potential for a cost reduction since it is possible to design the load adapted collector for low stagnation temperatures making it possible to use less expensive materials. One and the same collector design is suitable for a wide range of system sizes and roof inclinations. The report contains descriptions of optimized collector designs, properties of realistic collectors, and results of calculations of system output, stagnation performance and cost performance. Appropriate computer tools for optical analysis, optimization of collectors in systems and a very fast simulation model have been developed.

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This work treats the thermal and mechanical performances of gas-filled, flat plate solar collectors in order to achieve a better performance than that of air filled collectors. The gases examined are argon, krypton and xenon which all have lower thermal conductivity than air. The absorber is formed as a tray connected to the glass. The pressure of the gas inside is near to the ambient and since the gas volume will vary as the temperature changes, there are potential risks for fatigue in the material. One heat transfer model and one mechanical model were built. The mechanical model gave stresses and information on the movements. The factors of safety were calculated from the stresses, and the movements were used as input for the heat transfer model where the thermal performance was calculated. It is shown that gas-filled, flat plate solar collectors can be designed to achieve good thermal performance at a competitive cost. The best yield is achieved with a xenon gas filling together with a normal thick absorber, where normal thick means a 0.25 mm copper absorber. However, a great deal of energy is needed to produce the xenon gas, and if this aspect is taken into account, the krypton filling is better. Good thermal performance can also be achieved using less material; a collector with a 0.1 mm thick copper absorber and the third best gas, which is argon, still gives a better operating performance than a common, commercially produced, air filled collector with a 0.25 mm absorber. When manufacturing gas-filled flat plate solar collectors, one way of decreasing the total material costs significantly, is by changing absorber material from copper to aluminium. Best yield per monetary outlay is given by a thin (0.3 mm) alu-minium absorber with an argon filling. A high factor of safety is achieved with thin absorbers, large absorber areas, rectangular constructions with long tubes and short distances between glass and absorber. The latter will also give a thin layer of gas which gives good thermal performance. The only doubtii ful construction is an argon filled collector with a normal thick (> 0.50 mm) aluminium absorber. In general, an assessment of the stresses for the proposed construction together with appropriate tests are recommended before manufacturing, since it is hard to predict the factor of safety; if one part is reinforced, some other parts can experience more stress and the factor of safety actually drops.

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The annual cost of home care services of transport in Falun/Borlänge, is now at 31 million kronor. It is clear from previous research that it is possible to reduce these costs through a restructuring of the existing home-help service. The restructuring aims to have a higher proportion of older people, who are in need of care, to live in special accommodation, in order to reduce transport costs. Therefore there is a need for systems that allow home-help service to plan their operations in such a way that transport is working as efficiently as possible. Through better planning, there are profits to be done. The rewards are not only of an economic nature but also include a reduced environmental impact, better working environment, improving road safety, and better service. One way to achieve this is to give home-help service personnel better navigation aid when they move between the customers. The thesis describes such a solution through a developed prototype based on a standardized interaction between a planning and a navigation service. The thesis describes such a solution through a developed prototype based on a standardized interaction between a planning and a navigation service. Development work has also been a first step in developing a standardized information infrastructure for home-help service. The purpose of the thesis is, on the basis of theory and the experience we have acquired through the development of the prototype, to discuss general issues which are of interest when developing standardized information infrastructure.

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In a Nordic climate, space heating (SH) and domestic hot water (DHW) used in buildings constitute a considerable part of the total energy use in the country. For 2010, energy used for SH and DHW amounted to almost 90 TWh in Sweden which corresponds to 60 % of the energy used in the residential and service sector, or almost 24 % of the total final energy use for the country. Storing heat and cold with the use of thermal energy storage (TES) can be one way of increasing the energy efficiency of a building by opening up possibilities for alternative sources of heat or cold through a reduced mismatch between supply and demand. Thermal energy storage without the use of specific control systems are said to be passive and different applications using passive TES have been shown to increase energy efficiency and/or reduce power peaks of systems supplying the heating and cooling needs of buildings, as well as having an effect on the indoor climate. Results are however not consistent between studies and focus tend to be on the reduction of cooling energy or cooling power peaks. In this paper, passive TES introduced through an increased thermal mass in the building envelope to two single family houses with different insulation standard is investigated with building energy simulations. A Nordic climate is used and the focus of this study is both on the reduction of space heating demand and space heating power, as well as on reduction of excess temperatures in residential single family houses without active cooling systems. Care is taken to keep the building envelope characteristics other than the thermal mass equal for all cases so that any observations made can be derived to the change in thermal mass. Results show that increasing the sensible thermal mass in a single family house can reduce the heating demand only slightly (1-4 %) and reduce excess temperatures (temperatures above 24 degrees C) by up to 20 %. Adding a layer of PCM (phase change materials) to the light building construction can give similar reduction in heating demand and excess temperatures, however the phase change temperature is important for the results.

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Reduction of household energy consumption is one of the top issues in contemporary discussions on sustainable consumption. This chapter concerns one way through which consumption of purchased energy for house heating can be reduced; by having a solar thermal system added to one's house. However, the fact that one of the components - the solar collector - usually is situated on the roof or the facade of a building, is a recurrent impediment to such installations. In certain contexts, these attributes may melt into the building, while in others, they may be perceived as problematic. The latter may particularly be the case when the appearance of the building is of major imiportance, as with houses deemed worthy of preservation for coming generations. This chapter draws upon a study carried out in Visby Town, a walled Hanseatic town and a World Heritage site on the island of Gotland, Sweden.

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Heart failure is an illness that requires life-long treatment and often affects everyday aspects of a person’s life. Self-care is a significant part of the treatment. Good self-care resources make it possible for people with heart failure to make the lifestyle changes they often need to maintain or improve their level of health. Self-care means having knowledge of and being able to recognize the symptoms and signs of deterioration that can occur with heart failure, so that the person can take appropriate measures – and it also means knowing when it is time to seek professional help. The significance of self-care for heart failure has increased and will increase even more in the future, when monitoring one’s condition will be left more and more to the people themselves and those who take care of them. The object of the study was to learn what self-care measures people with heart failure say they apply in everyday life. The quantitative method of a questionnaire study (The European Heart Failure Self-Care Behaviour Scale) was used. Of the 94 people registered at a heart failure unit who were asked to complete the questionnaire, 58 of them consented. The results showed that more than 95% of the people with heart failure applied the recommended self-care measure of taking the medicines prescribed by their doctor. Many also applied the self-care measures of taking a rest during the day (83%) and taking it easy when they felt out of breath (78%). On the other hand, the self-care measures of daily weight control were applied only by 41%, daily exercise by only 48% and salt and fluid restrictions by only 59%. The self-care measures of contacting a doctor/nurse when noticing problems or symptoms of deterioration were applied by only 36% of those who felt out of breath and by only 43% of those who felt increased fatigue. The conclusion is that there is a need to improve the knowledge about and confidence in self-care treatment for people with heart failure. One way of achieving this is to show that people with heart failure check for symptoms and apply measures in their homes as part of the treatment and that this leads to an increased quality of life.

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This special issue of Nordic Journal of English Studies is devoted to the research in Irish Studies being carried out in Scandinavia by a group of scholars based in Denmark, Norway and Sweden, as well as scholars associated—in one way or another—with Scandinavia. Denmark is represented by the University of Aalborg; Norway, by scholars affiliated to the Universities of Agder, the Artic University of Norway, Bergen, and Stavanger; and Sweden is represented by scholars from the universities of Dalarna, Göteborg, Stockholm, Södertörn and Umeå. Included also in this special issue is the work of two former students, who completed their Masters’ degree in Irish literature at DUCIS (Dalarna University Centre for Irish Studies), Sweden—from Norway and China respectively. The collection also contains an article by Dara Waldron, Limerick Institute of Technology, Ireland, whof recently presented his research at the Higher Seminar in Dalarna. Contributions by the Irish poet, Mary O’Donnell, who participated in the Nordic Irish Studies Network (NISN) conference, hosted by DUCIS in December 2012, are also included.

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This special issue of Nordic Journal of English Studies is devoted to the research in Irish Studies being carried out in Scandinavia by a group of scholars based in Denmark, Norway and Sweden, as well as scholars associated—in one way or another—with Scandinavia. Denmark is represented by the University of Aalborg; Norway, by scholars affiliated to the Universities of Agder, the Artic University of Norway, Bergen, and Stavanger; and Sweden is represented by scholars from the universities of Dalarna, Göteborg, Stockholm, Södertörn and Umeå. Included also in this special issue is the work of two former students, who completed their Masters’ degree in Irish literature at DUCIS (Dalarna University Centre for Irish Studies), Sweden—from Norway and China respectively. The collection also contains an article by Dara Waldron, Limerick Institute of Technology, Ireland, whof recently presented his research at the Higher Seminar in Dalarna. Contributions by the Irish poet, Mary O’Donnell, who participated in the Nordic Irish Studies Network (NISN) conference, hosted by DUCIS in December 2012, are also included.