914 resultados para Global and Nonglobal Solutions


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The identification of biomarkers of vascular cognitive impairment is urgent for its early diagnosis. The aim of this study was to detect and monitor changes in brain structure and connectivity, and to correlate them with the decline in executive function. We examined the feasibility of early diagnostic magnetic resonance imaging (MRI) to predict cognitive impairment before onset in an animal model of chronic hypertension: Spontaneously Hypertensive Rats. Cognitive performance was tested in an operant conditioning paradigm that evaluated learning, memory, and behavioral flexibility skills. Behavioral tests were coupled with longitudinal diffusion weighted imaging acquired with 126 diffusion gradient directions and 0.3 mm(3) isometric resolution at 10, 14, 18, 22, 26, and 40 weeks after birth. Diffusion weighted imaging was analyzed in two different ways, by regional characterization of diffusion tensor imaging (DTI) indices, and by assessing changes in structural brain network organization based on Q-Ball tractography. Already at the first evaluated times, DTI scalar maps revealed significant differences in many regions, suggesting loss of integrity in white and gray matter of spontaneously hypertensive rats when compared to normotensive control rats. In addition, graph theory analysis of the structural brain network demonstrated a significant decrease of hierarchical modularity, global and local efficacy, with predictive value as shown by regional three-fold cross validation study. Moreover, these decreases were significantly correlated with the behavioral performance deficits observed at subsequent time points, suggesting that the diffusion weighted imaging and connectivity studies can unravel neuroimaging alterations even overt signs of cognitive impairment become apparent.

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Metaheuristic methods have become increasingly popular approaches in solving global optimization problems. From a practical viewpoint, it is often desirable to perform multimodal optimization which, enables the search of more than one optimal solution to the task at hand. Population-based metaheuristic methods offer a natural basis for multimodal optimization. The topic has received increasing interest especially in the evolutionary computation community. Several niching approaches have been suggested to allow multimodal optimization using evolutionary algorithms. Most global optimization approaches, including metaheuristics, contain global and local search phases. The requirement to locate several optima sets additional requirements for the design of algorithms to be effective in both respects in the context of multimodal optimization. In this thesis, several different multimodal optimization algorithms are studied in regard to how their implementation in the global and local search phases affect their performance in different problems. The study concentrates especially on variations of the Differential Evolution algorithm and their capabilities in multimodal optimization. To separate the global and local search search phases, three multimodal optimization algorithms are proposed, two of which hybridize the Differential Evolution with a local search method. As the theoretical background behind the operation of metaheuristics is not generally thoroughly understood, the research relies heavily on experimental studies in finding out the properties of different approaches. To achieve reliable experimental information, the experimental environment must be carefully chosen to contain appropriate and adequately varying problems. The available selection of multimodal test problems is, however, rather limited, and no general framework exists. As a part of this thesis, such a framework for generating tunable test functions for evaluating different methods of multimodal optimization experimentally is provided and used for testing the algorithms. The results demonstrate that an efficient local phase is essential for creating efficient multimodal optimization algorithms. Adding a suitable global phase has the potential to boost the performance significantly, but the weak local phase may invalidate the advantages gained from the global phase.

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The marine environment is certainly one of the most complex systems to study, not only because of the challenges posed by the nature of the waters, but especially due to the interactions of physical, chemical and biological processes that control the cycles of the elements. Together with analytical chemists, oceanographers have been making a great effort in the advancement of knowledge of the distribution patterns of trace elements and processes that determine their biogeochemical cycles and influences on the climate of the planet. The international academic community is now in prime position to perform the first study on a global scale for observation of trace elements and their isotopes in the marine environment (GEOTRACES) and to evaluate the effects of major global changes associated with the influences of megacities distributed around the globe. This action can only be performed due to the development of highly sensitive detection methods and the use of clean sampling and handling techniques, together with a joint international program working toward the clear objective of expanding the frontiers of the biogeochemistry of the oceans and related topics, including climate change issues and ocean acidification associated with alterations in the carbon cycle. It is expected that the oceanographic data produced this coming decade will allow a better understanding of biogeochemical cycles, and especially the assessment of changes in trace elements and contaminants in the oceans due to anthropogenic influences, as well as its effects on ecosystems and climate. Computational models are to be constructed to simulate the conditions and processes of the modern oceans and to allow predictions. The environmental changes arising from human activity since the 18th century (also called the Anthropocene) have made the Earth System even more complex. Anthropogenic activities have altered both terrestrial and marine ecosystems, and the legacy of these impacts in the oceans include: a) pollution of the marine environment by solid waste, including plastics; b) pollution by chemical and medical (including those for veterinary use) substances such as hormones, antibiotics, legal and illegal drugs, leading to possible endocrine disruption of marine organisms; and c) ocean acidification, the collateral effect of anthropogenic emissions of CO2 into the atmosphere, irreversible in the human life time scale. Unfortunately, the anthropogenic alteration of the hydrosphere due to inputs of plastics, metal, hydrocarbons, contaminants of emerging concern and even with formerly "exotic" trace elements, such us rare earth elements is likely to accelerate in the near future. These emerging contaminants would likely soon present difficulties for studies in pristine environments. All this knowledge brings with it a great responsibility: helping to envisage viable adaptation and mitigation solutions to the problems identified. The greatest challenge faced by Brazil is currently to create a framework project to develop education, science and technology applied to oceanography and related areas. This framework would strengthen the present working groups and enhance capacity building, allowing a broader Brazilian participation in joint international actions and scientific programs. Recently, the establishment of the National Institutes of Science and Technology (INCTs) for marine science, and the creation of the National Institute of Oceanographic and Hydrological Research represent an exemplary start. However, the participation of the Brazilian academic community in the latest assaults on the frontier of chemical oceanography is extremely limited, largely due to: i. absence of physical infrastructure for the preparation and processing of field samples at ultra-trace level; ii. limited access to oceanographic cruises, due to the small number of Brazilian vessels and/or absence of "clean" laboratories on board; iii. restricted international cooperation; iv. limited analytical capacity of Brazilian institutions for the analysis of trace elements in seawater; v. high cost of ultrapure reagents associated with processing a large number of samples, and vi. lack of qualified technical staff. Advances in knowledge, analytic capabilities and the increasing availability of analytical resources available today offer favorable conditions for chemical oceanography to grow. The Brazilian academic community is maturing and willing to play a role in strengthening the marine science research programs by connecting them with educational and technological initiatives in order to preserve the oceans and to promote the development of society.

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The paper presents a comparison of the theories of truth, and the solutions of the liar paradox, proposed by Thomas Bradwardine (c. 1290-1349), Jean Buridan (c. 1295-1358), and Alfred Tarski (1901-1983).

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In this paper, I aim at relating passions to evil in Kant's philosophy. I begin by explaining the difference between affects and passions in the textAnthropology from a Pragmatic Point of View. Kant claims that both affects and passions are illnesses of the mind, because both affect and passion hinder the sovereignty of reason. I show that passions are worse than affects for the purpose of pure reason. Second, I relate affects and passions to the degrees of the propensity to evil in theReligion. I analyze the idea of an ethical community as a way to overcome the evil, which goes beyond political and anthropological solutions suggested by Kant.

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The objective of this Bachelor's Thesis is to find out the role of social media in the B-to-B marketing environment of the information technology industry and to discover how IT-firms utilize social media as a part of their customer reference marketing. To reach the objectives the concepts of customer reference marketing and social media are determined. Customer reference marketing can be characterized as one of the most practically relevant but academically relatively overlooked ways in which a company can leverage its customers and delivered solutions and use them as references in its marketing activities. We will cover which external and internal functions customer references have, that contribute to the growth and performance of B-to-B firms. We also address the three mechanisms of customer reference marketing which are 'status transfer', 'validation through testimonials' and 'demonstration of experience and prior performance'. The concept of social media stands for social interaction and creation of user-based content which exclusively occurs through Internet. The social media are excellent tools for networking because of the fast and easy access, easy interaction and vast amount of multimedia attributes. The allocation of social media is determined. The case company helps clarify the specific characteristics of social media usage as part of customer-reference-marketing activities. For IT-firms the best channels to utilize social media in their customer reference marketing activities are publishing and distribution services of content and networking services.

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In this article, a methodology is used for the simultaneous determination of the effective diffusivity and the convective mass transfer coefficient in porous solids, which can be considered as an infinite cylinder during drying. Two models are used for optimization and drying simulation: model 1 (constant volume and diffusivity, with equilibrium boundary condition), and model 2 (constant volume and diffusivity with convective boundary condition). Optimization algorithms based on the inverse method were coupled to the analytical solutions, and these solutions can be adjusted to experimental data of the drying kinetics. An application of optimization methodology was made to describe the drying kinetics of whole bananas, using experimental data available in the literature. The statistical indicators enable to affirm that the solution of diffusion equation with convective boundary condition generates results superior than those with the equilibrium boundary condition.

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This research aims at studying spatial autocorrelation of Landsat/TM based on normalized difference vegetation index (NDVI) and green vegetation index (GVI) of soybean of the western region of the State of Paraná. The images were collected during the 2004/2005 crop season. The data were grouped into five vegetation index classes of equal amplitude, to create a temporal map of soybean within the crop cycle. Moran I and Local Indicators of Spatial Autocorrelation (LISA) indices were applied to study the spatial correlation at the global and local levels, respectively. According to these indices, it was possible to understand the municipality-based profiles of tillage as well as to identify different sowing periods, providing important information to producers who use soybean yield data in their planning.

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This thesis focuses on integration in project business, i.e. how projectbased companies organize their product and process structures when they deliver industrial solutions to their customers. The customers that invest in these solutions run their businesses in different geographical, political and economical environments, which should be acknowledged by the supplier when providing solutions comprising of larger and more complex scopes than previously supplied to these customers. This means that the suppliers are increasing their supply range by taking over some of the activities in the value chain that have traditionally been handled by the customer. In order to be able to provide the functioning solutions, including more engineering hours, technical equipment and a wider project network, a change is needed in the mindset in order to be able to carry out and take the required responsibility that these new approaches bring. For the supplier it is important to be able to integrate technical products, systems and services, but the supplier also needs to have the capabilities to integrate the cross-functional organizations and departments in the project network, the knowledge and information between and within these organizations and departments, along with inputs from the customer into the product and process structures during the lifecycle of the project under development. Hence, the main objective of this thesis is to explore the challenges of integration that industrial projects meet, and based on that, to suggest a concept of how to manage integration in project business by making use of integration mechanisms. Integration is considered the essential process for accomplishing an industrial project, whereas the accomplishment of the industrial project is considered to be the result of the integration. The thesis consists of an extended summary and four papers, that are based on three studies in which integration mechanisms for value creation in industrial project networks and the management of integration in project business have been explored. The research is based on an inductive approach where in particular the design, commissioning and operations functions of industrial projects have been studied, addressing entire project life-cycles. The studies have been conducted in the shipbuilding and power generation industries where the scopes of supply consist of stand-alone equipment, equipment and engineering, and turnkey solutions. These industrial solutions include demanding efforts in engineering and organization. Addressing the calls for more studies on the evolving value chains of integrated solutions, mechanisms for inter- and intra-organizational integration and subsequent value creation in project networks have been explored. The research results in thirteen integration mechanisms and a typology for integration is proposed. Managing integration consists of integrating the project network (the supplier and the sub-suppliers) and the customer (the customer’s business purpose, operations environment and the end-user) into the project by making use of integration mechanisms. The findings bring new insight into research on industrial project business by proposing integration of technology and engineering related elements with elements related to customer oriented business performance in contemporary project environments. Thirteen mechanisms for combining products and the processes needed to deliver projects are described and categorized according to the impact that they have on the management of knowledge and information. These mechanisms directly relate to the performance of the supplier, and consequently to the functioning of the solution that the project provides. This thesis offers ways to promote integration of knowledge and information during the lifecycle of industrial projects, enhancing the development towards innovative solutions in project business.

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The necessity of EC (Electronic Commerce) and enterprise systems integration is perceived from the integrated nature of enterprise systems. The proven benefits of EC to provide competitive advantages to the organizations force enterprises to adopt and integrate EC with their enterprise systems. Integration is a complex task to facilitate seamless flow of information and data between different systems within and across enterprises. Different systems have different platforms, thus to integrate systems with different platforms and infrastructures, integration technologies, such as middleware, SOA (Service-Oriented Architecture), ESB (Enterprise Service Bus), JCA (J2EE Connector Architecture), and B2B (Business-to-Business) integration standards are required. Huge software vendors, such as Oracle, IBM, Microsoft, and SAP suggest various solutions to address EC and enterprise systems integration problems. There are limited numbers of literature about the integration of EC and enterprise systems in detail. Most of the studies in this area have focused on the factors which influence the adoption of EC by enterprise or other studies provide limited information about a specific platform or integration methodology in general. Therefore, this thesis is conducted to cover the technical details of EC and enterprise systems integration and covers both the adoption factors and integration solutions. In this study, many literature was reviewed and different solutions were investigated. Different enterprise integration approaches as well as most popular integration technologies were investigated. Moreover, various methodologies of integrating EC and enterprise systems were studied in detail and different solutions were examined. In this study, the influential factors to adopt EC in enterprises were studied based on previous literature and categorized to technical, social, managerial, financial, and human resource factors. Moreover, integration technologies were categorized based on three levels of integration, which are data, application, and process. In addition, different integration approaches were identified and categorized based on their communication and platform. Also, different EC integration solutions were investigated and categorized based on the identified integration approaches. By considering different aspects of integration, this study is a great asset to the architectures, developers, and system integrators in order to integrate and adopt EC with enterprise systems.

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Panel at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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Collective Action in Commons: Its Diverse Ends and Consequences explores new ways in which collective action theories can contribute to our understanding of natural resource management, especially the management of common-pools. Combining classical collective action theories and lessons from earlier empirical works, the study shows that cooperation among resource users is not only a possible solution to “the tragedy of the commons”, but it can be a part of the problem as well. That is, successful cooperation may increase the likelihood of resource depletion, for example, through more effective resource utilization or collusion against sanctioning and monitoring systems. The study also explores how analytic narratives can be used to tell the story behind problems of resource use and their solutions, including the diverse roles of cooperation.

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Sustainability, in its modern meaning, has been discussed for more than forty years. However, many experts believe that humanity is still far from being sustainable. Some experts have argued that humanity should seek survivable development because it is too late for sustainable one, since 1990s. Obviously, some problems prevented humanity from becoming sustainable. This thesis focuses on the agenda of sustainability discussions and seeks for the essential topics missing from it. For this purpose, the research is conducted on 21 out of 33 books endorsed by the Club of Rome. All of these books are titled ‘a report to the Club of Rome’. The Club of Rome is an organization that has been constantly working on the problems of humankind for the past 40 years. This thesis has three main components: first, the messages of the reports to the Club of Rome, second, academics perceptions of the Club, and third, the Club member perceptions of its evolution, messages and missing topics. This thesis investigates the evolution of four aspects in the reports. The first one is the agenda of the reports. The second one is the basic approaches of the Club (i.e., global, long-term and holistic). The third one is the ways that the reports treat free market and growth ideology. The fourth one is the approach of the reports toward components of the global complex system (i.e., society, economy and politics). The outline of the thesis is as follows. First, the original reports are briefly summarized. After this, the academic perceptions are discussed and structured around three concepts (i.e., futures studies, sustainability and degrowth). In the final step, the perceptions of the experts are collected and analysed, using a variation of Delphi method, called ‘in-depth interviews’, and ‘quality content analysis’ method. This thesis is useful for those interested in sustainability, global problems, and the Club of Rome. This thesis concludes that the reports from 1972 up to 1980 were cohesive in discussing topics related to the problems of humankind. The topics of the reports are fragmented after this period. The basic approaches of CoR are visible in all the reports. However, after 1980, those approaches and especially holistic thinking are only visible in the background. Regarding the free market and growth ideology, although all the reports are against them, the early reports were more explicitly expressing their disagreement. A milestone is noticeable around 1980 when such objections went completely to the background. However, recent reports are more similar to those of 1970s both in adopting a holistic approach and in explicitly criticizing free market and growth ideology. Finally, concerning the components of global complex system, the society is excluded and the focus of the reports is on politics, economy and their relation. Concerning the topics missing from the debate, this thesis concludes that no major research has been conducted on the fundamental and underlying reasons of the problems (e.g. beliefs, values and culture). Studying the problems without considering their underlying reasons, obviously, leads to superficial and ineffective solutions. This might be one of the reasons that sustainability discussions have as yet led to no concrete result.

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We have developed a system with two epi-illumination sources, a DC-regulated lamp for transillumination and mechanical switches for rapid shift of illumination and detection of defined areas (250-750 µm²) by fluorescence and phosphorescence videomicroscopy. The system permits investigation of standard microvascular parameters, vascular permeability as well as intra- and extravascular PO2 by phosphorescence quenching of Pd-meso-tetra (4-carboxyphenyl) porphine (PORPH). A Pechan prism was used to position a defined region over the photomultiplier and TV camera. In order to validate the system for in vivo use, in vitro tests were performed with probes at concentrations that can be found in microvascular studies. Extensive in vitro evaluations were performed by filling glass capillaries with solutions of various concentrations of FITC-dextran (diluted in blood and in saline) mixed with different amounts of PORPH. Fluorescence intensity and phosphorescence decay were determined for each mixture. FITC-dextran solutions without PORPH and PORPH solutions without FITC-dextran were used as references. Phosphorescence decay curves were relatively unaffected by the presence of FITC-dextran at all concentrations tested (0.1 µg/ml to 5 mg/ml). Likewise, fluorescence determinations were performed in the presence of PORPH (0.05 to 0.5 mg/ml). The system was successfully used to study macromolecular extravasation and PO2 in the rat mesentery circulation under controlled conditions and during ischemia-reperfusion.

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The type of fluid used during resuscitation may have an important impact on tissue edema. We evaluated the impact of two different regimens of fluid resuscitation on hemodynamics and on lung and intestinal edema during splanchnic hypoperfusion in rabbits. The study included 16 female New Zealand rabbits (2.9 to 3.3 kg body weight, aged 8 to 12 months) with splanchnic ischemia induced by ligation of the superior mesenteric artery. The animals were randomized into two experimental groups: group I (N = 9) received 12 mL·kg-1·h-1 lactated Ringer solution and 20 mL/kg 6% hydroxyethyl starch solution; group II (N = 7) received 36 mL·kg-1·h-1 lactated Ringer solution and 20 mL/kg 0.9% saline. A segment from the ileum was isolated to be perfused. A tonometric catheter was placed in a second gut segment. Superior mesenteric artery (Q SMA) and aortic (Qaorta) flows were measured using ultrasonic flow probes. After 4 h of fluid resuscitation, tissue specimens were immediately removed for estimations of gut and lung edema. There were no differences in global and regional perfusion variables, lung wet-to-dry weight ratios and oxygenation indices between groups. Gut wet-to-dry weight ratio was significantly lower in the crystalloid/colloid-treated group (4.9 ± 1.5) than in the crystalloid-treated group (7.3 ± 2.4) (P < 0.05). In this model of intestinal ischemia, fluid resuscitation with crystalloids caused more gut edema than a combination of crystalloids and colloids.