870 resultados para growing domain
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First-order temporal logic is a concise and powerful notation, with many potential applications in both Computer Science and Artificial Intelligence. While the full logic is highly complex, recent work on monodic first-order temporal logics has identified important enumerable and even decidable fragments. In this paper, we develop a clausal resolution method for the monodic fragment of first-order temporal logic over expanding domains. We first define a normal form for monodic formulae and then introduce novel resolution calculi that can be applied to formulae in this normal form. We state correctness and completeness results for the method. We illustrate the method on a comprehensive example. The method is based on classical first-order resolution and can, thus, be efficiently implemented.
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In the domain of aerospace aftermarkets, which often has long supply chains that feed into the maintenance of aircraft, contracts are used to establish agreements between aircraft operators and maintenance suppliers. However, violations at the bottom of the supply chain (part suppliers) can easily cascade to the top (aircraft operators), making it difficult to determine the source of the violation, and seek to address it. In this context, we have developed a global monitoring architecture that ensures the detection of norm violations and generates explanations for the origin of violations. In this paper, we describe the implementation and deployment of a global monitor in the aerospace domain of [8] and show how it generates explanations for violations within the maintenance supply chain. We show how these explanations can be used not only to detect violations at runtime, but also to uncover potential problems in contracts before their deployment, thus improving them.
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In industrial polymer and synthetic rubber production facilities, workers are exposed to 1,3-butadiene. This compound is converted in vivo to 1,2,3,4-diepoxybutane (DEB) and has been linked to increased incidences of cancer in these individuals. Carcinogenesis has been attributed to formation of DEB induced DNA interstrand cross-links. Previous studies have demonstrated that DEB cross-links deoxyguanosine residues within 5'-GNC sequences in synthetic DNA, in restriction fragments, and in defined sequence nucleosomes. The current study utilized the polymerase chain reaction (PCR) to examine DEB damage frequencies within nuclear genes, found within "open" regions of chromatin, as compared to regions of unexpressed sequence that reside in tightly packed, "closed" chromatin, to more closely model DEB reactivity in vivo. These initial studies have been performed in chicken liver homogenates. Preliminarily, we have found a dose-dependent DEB lesion-forming response within "open" chromatin. DEB appears to have little-to-no effect upon regions of "closed" chromatin.
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Diepoxybutane (DEB), a known industrial carcinogen, reacts with DNA primarily at the N7 position of deoxyguanosine residues and creates interstrand cross-links at the sequence 5'-GNC. Since N7-N7 cross-links cause DNA to fragment upon heating, quantative polymerase chain reaction (QPCR) is being used in this experiment to measure the amount of DEB damage (lesion frequency) with three different targets-mitochondrial (unpackaged), open chromatin region, and closed chromatin region. Initial measurements of DEB damage within these three targets were not consistent because the template DNA was not the limiting reagent in the PCR. Follow-up PCR trials using a limiting amount of DNA are still in progress although initial experimentation looks promising. Sequencing of these three targets to confirm the primer targets has only been successfully performed for the closed chromatin target and does not match the sequence from NIH used to design that primer pair. Further sequencing trials need to be conducted on all three targets to assure that a mitochondrial, open chromatin, and closed chromatin region are actually being amplified in this experimental series.
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Now 40, Colby’s Environmental Studies Program is growing exponentially, equipping students to tackle real-world problems.
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This dissertation aims at examining empirical evidences obtained in the light of taxonomies and strategies for measuring firms technological capabilities and innovation in the context of developing countries, motivated by the fact that debates and studies directed to innovation has been intensified, for the last thirty years, by the recognition of its vital and growing importance to the technological, economic, competitive and industrial development of firms and countries. Two main tendencies can be identified on this debate. At one side, it¿s the literature related to the developed countries logic, whose companies are, in majority, positioned at the technological frontier, characterized by the domain of innovative advanced capabilities, directed to its sustaining, deepening and renewal. At the other side, there are the perspectives directed to the developing countries reality, where there is a prevalence of companies with deficiency of resources, still in process of accumulating basic and intermediate technological capabilities, with characteristics and technological development trajectories distinct or even reverse from those of developing countries. From this last tradition of studies, the measuring approaches based in C&T indicators and in types and levels of technological capabilities stand out. The first offers a macro level, aggregated perspective, through the analysis of a representative sample of firms, seeking to the generation of internationally comparable data, without addressing the intraorganizational specificities and nuances of the paths of technological accumulation developed by the firms, using, mostly, R&D statistics, patents, individual qualifications, indicators that carry their own limitations. On the other hand, studies that examine types and levels of technological capabilities are scarce, usually directed to a small sample of firms and/or industrial sectors. Therefore, in the light of the focus and potentialities of each of the perspectives, this scenario exposes a lack of studies that examine, in a parallel and complementary way, both types of strategies, seeking to offer more realistic, consistent and concrete information about the technological reality of developing countries. In order to close this gap, this dissertation examines (i) strategies of innovation measurement in the contexts of developing countries based on traditional approaches and C&T indicators, represented by four innovation surveys - ECIB, PINTEC, PAEP and EAI, and, (ii) from the perspective of technological capabilities as an intrinsic resource of the firm, the development of which occurs in a cumulative way and based on learning, presents and extracts generalizations of empirical applications of a metric that identifies types and levels of technological capabilities, through a dynamic and intra-firm perspective. The exam of the empirical evidences of the two approaches showed what each one of the metrics are capable to offer and the way they can contribute to the generation of information that reflect the technological development of specific industrial sectors in developing countries. In spite of the fact that the focus, objective, perspective, inclusion, scope and lens used are substantially distinct, generating, on a side, an aggregated view, and of other, an intra-sector, intra-organizational and specific view, the results suggest that the use of one doesn't implicate discarding or abdicating the other. On the contrary, using both in a complementary way means the generation of more complete, rich and relevant evidences and analysis that offer a realistic notion of the industrial development and contribute in a more direct way to the design of corporate strategies and government policies, including those directed to the macro level aspects just as those more specific and focused, designed to increment and foment firms in-house innovative efforts.
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A experiência internacional de empresas de países em desenvolvimento é relativamente nova, assim como os estudos sobre o desenvolvimento dessas atividades por esses países e, em particular, pelo Brasil. Esta pesquisa visou contribuir para o conhecimento sobre como as empresas brasileiras se internacionalizam e, para tanto, foi realizado um estudo de caso em profundidade com a Marcopolo S. A., uma organização em estágio avançado de operações internacionais. Apoiando-se em vertentes comportamentais e econômicas da literatura sobre o tema, buscou-se investigar o processo de internacionalização dessa empresa – suas motivações, como ela expandiu seus negócios no exterior, quais foram os principais obstáculos enfrentados e fatores facilitadores do processo. Também se estudou a relação entre internacionalização e resultados financeiros obtidos e a influência de políticas públicas. Atuar em mercados externos foi uma forma de ampliação de mercados e de diversificação de riscos para a empresa e hoje é o foco de sua estratégia de crescimento. O processo se desenvolveu de forma incremental, evoluindo de operações de menor comprometimento e em países mais próximos do Brasil, até a instalação de unidades em mercados mais distantes. Obstáculos de natureza econômica e cultural influenciaram suas atividades e o domínio tecnológico de produtos e de processos, assim como parcerias com montadoras, foram facilitadores do seu desenvolvimento internacional. Os resultados da pesquisa confirmaram os pressupostos da abordagem comportamental, reforçando a hipótese gradualista sustentada pela Teoria de Uppsala. O Paradigma Eclético também explicou os investimentos diretos realizados pela empresa, o que levou à constatação de que as duas linhas teóricas se complementam para explicar o caso. As operações da companhia em mercados externos foram historicamente mais rentáveis do que no mercado doméstico e esses resultados tornaram-se mais expressivos com a instalação de unidades no exterior. Por fim, constatou-se que algumas medidas de apoio governamental geraram efeitos positivos para as exportações, mas que não houve influência de políticas públicas para instalação de fábricas em territórios estrangeiros.
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In recent years, emerging countries have assumed an increasingly prominent position in the world economy, as growth has picked up in these countries and slowed in developed economies. Two related phenomena, among others, can be associated with this growth: emerging countries were less affected by the 2008-2009 global economic recession; and they increased their participation in foreign direct investment, both inflows and outflows. This doctoral dissertation contributes to research on firms from emerging countries through four independent papers. The first group of two papers examines firm strategy in recessionary moments and uses Brazil, one of the largest emerging countries, as setting for the investigation. Data were collected through a survey on Brazilian firms referring to the 2008-2009 global recession, and 17 hypotheses were tested using structural equation modeling based on partial least squares. Paper 1 offered an integrative model linking RBV to literatures on entrepreneurship, improvisation, and flexibility to indicate the characteristics and capabilities that allow a firm to have superior performance in recessions. We found that firms that pre-recession have a propensity to recognize opportunities and improvisation capabilities for fast and creative actions have superior performance in recessions. We also found that entrepreneurial orientation and flexibility have indirect effects. Paper 2 built on business cycle literature to study which strategies - pro-cyclical or counter-cyclical – enable superior performance in recessions. We found that while most firms pro-cyclically reduce costs and investments during recessions, a counter-cyclical strategy of investing in opportunities created by changes in the environment enables superior performance. Most successful are firms with a propensity to recognize opportunities, entrepreneurial orientation to invest, and flexibility to efficiently implement these investments. The second group of two papers investigated international expansion of multinational enterprises, particularly the use of distance for their location decisions. Paper 3 proposed a conceptual framework to examine circumstances under which distance is less important for international location decisions, taking the new perspective of economic institutional distance as theoretical foundation. The framework indicated that the general preference for low-distance countries is lower: (1) when the company is state owned, rather than private owned; (2) when its internationalization motives are asset, resource, or efficiency seeking, as opposed to market seeking; and (3) when internationalization occurred after globalization and the advent of new technologies. Paper 4 compared five concurrent perspectives of distance and indicated their suitability to the study of various issues based on industry, ownership, and type, motive, and timing of internationalization. The paper also proposed that distance represents the disadvantages of host countries for international location decisions; as such, it should be used in conjunction with factors that represent host country attractiveness, or advantages as international locations. In conjunction, papers 3 and 4 provided additional, alternative explanations for the mixed empirical results of current research on distance. Moreover, the studies shed light into the discussion of differences between multinational enterprises from emerging countries versus those from advanced countries.
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Industrial companies in developing countries are facing rapid growths, and this requires having in place the best organizational processes to cope with the market demand. Sales forecasting, as a tool aligned with the general strategy of the company, needs to be as much accurate as possible, in order to achieve the sales targets by making available the right information for purchasing, planning and control of production areas, and finally attending in time and form the demand generated. The present dissertation uses a single case study from the subsidiary of an international explosives company based in Brazil, Maxam, experiencing high growth in sales, and therefore facing the challenge to adequate its structure and processes properly for the rapid growth expected. Diverse sales forecast techniques have been analyzed to compare the actual monthly sales forecast, based on the sales force representatives’ market knowledge, with forecasts based on the analysis of historical sales data. The dissertation findings show how the combination of both qualitative and quantitative forecasts, by the creation of a combined forecast that considers both client´s demand knowledge from the sales workforce with time series analysis, leads to the improvement on the accuracy of the company´s sales forecast.
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O objectivo deste projecto é a comparação entre os prós e contras de gestão passiva e ativa através da realização de um estudo estatístico de várias estratégias através dos Exchange-Traded Funds. Em particular, a análise vai passar pela estratégia mais passiva, ou seja, buy and hold, para um grau diferente de active indexing management, tais como rotações do sector e / ou classe de ativos com base no bottom-up, top-down e indicadores técnicos. A análise mostra que as estratégias ativas, se forem devidamente aplicadas, conseguem obter retornos ajustados ao risco substancialmente superiores quando comparados com uma abordagem passiva, superando as questões de custos de transação e diversificação que normalmente são reivindicadas por uma gestão passiva.
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Online geographic-databases have been growing increasingly as they have become a crucial source of information for both social networks and safety-critical systems. Since the quality of such applications is largely related to the richness and completeness of their data, it becomes imperative to develop adaptable and persistent storage systems, able to make use of several sources of information as well as enabling the fastest possible response from them. This work will create a shared and extensible geographic model, able to retrieve and store information from the major spatial sources available. A geographic-based system also has very high requirements in terms of scalability, computational power and domain complexity, causing several difficulties for a traditional relational database as the number of results increases. NoSQL systems provide valuable advantages for this scenario, in particular graph databases which are capable of modeling vast amounts of inter-connected data while providing a very substantial increase of performance for several spatial requests, such as finding shortestpath routes and performing relationship lookups with high concurrency. In this work, we will analyze the current state of geographic information systems and develop a unified geographic model, named GeoPlace Explorer (GE). GE is able to import and store spatial data from several online sources at a symbolic level in both a relational and a graph databases, where several stress tests were performed in order to find the advantages and disadvantages of each database paradigm.
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The domain of Knowledge Discovery (KD) and Data Mining (DM) is of growing importance in a time where more and more data is produced and knowledge is one of the most precious assets. Having explored both the existing underlying theory, the results of the ongoing research in academia and the industry practices in the domain of KD and DM, we have found that this is a domain that still lacks some systematization. We also found that this systematization exists to a greater degree in the Software Engineering and Requirements Engineering domains, probably due to being more mature areas. We believe that it is possible to improve and facilitate the participation of enterprise stakeholders in the requirements engineering for KD projects by systematizing requirements engineering process for such projects. This will, in turn, result in more projects that end successfully, that is, with satisfied stakeholders, including in terms of time and budget constraints. With this in mind and based on all information found in the state-of-the art, we propose SysPRE - Systematized Process for Requirements Engineering in KD projects. We begin by proposing an encompassing generic description of the KD process, where the main focus is on the Requirements Engineering activities. This description is then used as a base for the application of the Design and Engineering Methodology for Organizations (DEMO) so that we can specify a formal ontology for this process. The resulting SysPRE ontology can serve as a base that can be used not only to make enterprises become aware of their own KD process and requirements engineering process in the KD projects, but also to improve such processes in reality, namely in terms of success rate.
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Temporally-growing frontal meandering and occasional eddy-shedding is observed in the Brazil Current (BC) as it flows adjacent to the Brazilian Coast. No study of the dynamics of this phenomenon has been conducted to date in the region between 22 degrees S and 25 degrees S. Within this latitude range, the flow over the intermediate continental slope is marked by a current inversion at a depth that is associated with the Intermediate Western Boundary Current (IWBC). A time series analysis of 10-current-meter mooring data was used to describe a mean vertical profile for the BC-IWBC jet and a typical meander vertical structure. The latter was obtained by an empirical orthogonal function (EOF) analysis that showed a single mode explaining 82% of the total variance. This mode structure decayed sharply with depth, revealing that the meandering is much more vigorous within the BC domain than it is in the IWBC region. As the spectral analysis of the mode amplitude time series revealed no significant periods, we searched for dominant wavelengths. This search was done via a spatial EOF analysis on 51 thermal front patterns derived from digitized AVHRR images. Four modes were statistically significant at the 95% confidence level. Modes 3 and 4, which together explained 18% of the total variance, are associated with 266 and 338-km vorticity waves, respectively. With this new information derived from the data, the [Johns, W.E., 1988. One-dimensional baroclinically unstable waves on the Gulf Stream potential vorticity gradient near Cape Hatteras. Dyn. Atmos. Oceans 11, 323-350] one-dimensional quasi-geostrophic model was applied to the interpolated mean BC-IWBC jet. The results indicated that the BC system is indeed baroclinically unstable and that the wavelengths depicted in the thermal front analysis are associated with the most unstable waves produced by the model. Growth rates were about 0.06 (0.05) days(-1) for the 266-km (338-km) wave. Moreover, phase speeds for these waves were low compared to the surface BC velocity and may account for remarks in the literature about growing standing or stationary meanders off southeast Brazil. The theoretical vertical structure modes associated with these waves resembled very closely to the one obtained for the current-meter mooring EOF analysis. We interpret this agreement as a confirmation that baroclinic instability is an important mechanism in meander growth in the BC system. (C) 2008 Elsevier B.V. All rights reserved.