978 resultados para Evolutionary stable strategy


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The paper proposes an IS process model comprising inputs, development, outputs and a feedback loop based on performance measurement and its interpretation. The feedback impacts on the inputs and development components. Inputs are comprised of market information. human resources, diversity, value creation and host country environmental factors. Development includes preparation and learning. planning and scrutinising partnerships. anticipating impacts of globalisation and experience effects. Outputs comprise structure, scope of operations, target countries. facility location and positioning. Performance interpretation explains rapid and major changes in IS outputs, such as structure and business unit portfolios, whilst process complexity explains observed output similarities for organisations reacting to similar inputs and suggests an evolutionary approach in their determination.

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There usually exist diverse variations in face images taken under uncontrolled conditions. Most previous work on face recognition focuses on particular variations and usually assume the absence of others. Such work is called controlled face recognition. Instead of the ‘divide and conquer’ strategy adopted by controlled face recognition, this paper presents one of the first attempts directly aiming at uncontrolled face recognition. The solution is based on Individual Stable Neural Network (ISNN) proposed in this paper. ISNN can map a face image into the so-called Individual Stable Space (ISS), the feature space that only expresses personal characteristics, which is the only useful information for recognition. There are no restrictions for the face images fed into ISNN. Moreover, unlike many other robust face recognition methods, ISNN does not require any extra information (such as view angle) other than the personal identities during training. These advantages of ISNN make it a very practical approach for uncontrolled face recognition. In the experiments, ISNN is tested on two large face databases with vast variations and achieves the best performance compared with several popular face recognition techniques.

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Building demolition has been undergoing evolutionary development in its technologies for several decades. In order to achieve a high level of demolition material reuse and recycling, new management approaches are also necessitated, in particular in conjunction with the applications of information technologies. The development of an information system for demolition project management is an impactful strategy to support various demolition activities including waste exchange, demolition visualization, and demolition method selection and evaluation. This paper aims to develop a framework of an integrated information system for building demolition project demolition decision-making and waste minimization. The components of this information system and their interactions are demonstrated through a specifical demolition project.

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International strategy (IS) is the approach by which an organisation's capabilities and resources are directed to generate value utilising the global market's opportunities (and risks). Many of the largest multinationals invest significant resources in their IS, however, the literature does not offer any substantive model for the process. This paper presents a model of the IS process which comprises two parts, the first part is made up of inputs, development and outputs and the second comprises a feedback loop based on organisational performance measurement and its interpretation which impacts on the first part stages of inputs and development. The content of the model is explained and justified using examples of practice. Inputs are comprised of market information, human resources, diversity and value creation and host country environmental factors. Development is comprised of preparation and learning, planning and scrutinising partnerships, anticipating impacts of globalisation, anticipating impacts of technology, location, experience effects, planning competencies, planning for cost effectiveness, scenario planning, planning structures and operations, leadership and ethics. Outputs are comprised of structure, scope of operations, target countries, facility location and positioning. Performance interpretation explains rapid and major changes in IS outputs, such as structure
and business unit portfolios, whilst process complexity explains observed output similarities for organisations reacting to similar inputs and suggests an evolutionary approach in their determination.

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In sexually dimorphic ungulates, sexual segregation is hypothesized to have evolved because of sex-specific differences in body size and/or reproductive strategies. We tested these alternative hypotheses in kangaroos, which are ecological analogues of ungulates. Kangaroos exhibit a wide range of body sizes, particularly among mature males, and so the effects of body size and sex can be distinguished. We tested predictions derived from these hypotheses by comparing the distribution of three sex–sex size classes of western grey kangaroos Macropus fuliginosus, in different habitats, and the composition of groups of kangaroos, across seasons. In accordance with the predation risk-reproductive strategy hypothesis, during the non-breeding season, females, which were more susceptible to predation than larger males, and were accompanied by vulnerable young-at-foot, were over-represented in secure habitats. Large males, which were essentially immune to predation, occurred more often than expected in nutrient-rich habitat, and small males, which faced competing demands of predator avoidance and feeding, were intermediate between females and large males in their distribution across habitats. During the breeding season, females continued to be over-represented in secure habitats when their newly emerged pouch young were most vulnerable to predation. All males occupied these same habitats to maximize their chances of securing mates. Consistent with the social hypotheses, groups composed of individuals of the same sex, irrespective of body size, were over-represented in the population during the non-breeding season, while during the breeding season all males sought females so that mixed-sex groups predominated. These results indicate that body size and reproductive strategies are both important, yet independent, factors influencing segregation in western grey kangaroos.

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There usually exist many kinds of variations in face images taken under uncontrolled conditions, such as changes of pose, illumination, expression, etc. Most previous works on face recognition (FR) focus on particular variations and usually assume the absence of others. Instead of such a ldquodivide and conquerrdquo strategy, this paper attempts to directly address face recognition under uncontrolled conditions. The key is the individual stable space (ISS), which only expresses personal characteristics. A neural network named ISNN is proposed to map a raw face image into the ISS. After that, three ISS-based algorithms are designed for FR under uncontrolled conditions. There are no restrictions for the images fed into these algorithms. Moreover, unlike many other FR techniques, they do not require any extra training information, such as the view angle. These advantages make them practical to implement under uncontrolled conditions. The proposed algorithms are tested on three large face databases with vast variations and achieve superior performance compared with other 12 existing FR techniques.

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I have committed a significant period of time (in my case five years) to the purpose development of learning environments, with the belief that it would improve the self-actualisation and self-motivation of students and teachers alike. I consider it important to record and measure performance as we progressed toward such an outcome. Education researchers and practitioners alike, in the higher (university/tertiary) education systems, are seeking among new challenges to engage students and teachers in learning (James, 2001). However, studies to date show a confusing landscape littered with a multiplicity of interpretations and terms, successes and failures. As the discipline leader of the Information Technology, Systems and Multimedia (ITSM) Discipline, Swinburne University of Technology, Lilydale, I found myself struggling with this paradigm. I also found myself being torn between what presents as pragmatic student learning behaviour and the learner-centred teaching ideal reflected in the Swinburne Lilydale mission statement. The research reported in this folio reflects my theory and practice as discipline leader of the ITSM Discipline and the resulting learning environment evolution during the period 1997/8 to 2003. The study adds to the material evidence of extant research through firstly, a meta analysis of the learning environment implemented by the ITSM Discipline as recorded in peer reviewed and published papers; and secondly, a content analysis of student learning approaches, conducted on data reported from a survey of ‘learning skills inventory’ originally conducted by the ITSM Discipline staff in 2002. In 1997 information and communication technologies (ICT) were beginning to provide plausible means for electronic distribution of learning materials on a flexible and repeatable basis, and to provide answers to the imperative of learning materials distribution relating to an ITSM Discipline new course to begin in 1998. A very short time frame of three months was available prior to teaching the course. The ITSM Discipline learning environment development was an evolutionary process I began in 1997/8 initially from the requirement to publish print-based learning guide materials for the new ITSM Discipline subjects. Learning materials and student-to-teacher reciprocal communication would then be delivered and distributed online as virtual learning guides and virtual lectures, over distance as well as maintaining classroom-based instruction design. Virtual here is used to describe the use of ICT and Internet-based approaches. No longer would it be necessary for students to attend classes simply to access lecture content, or fear missing out on vital information. Assumptions I made as discipline leader for the ITSM Discipline included, firstly, that learning should be an active enterprise for the students, teachers and society; secondly, that each student comes to a learning environment with different learning expectations, learning skills and learning styles; and thirdly, that the provision of a holistic learning environment would encourage students to be self-actualising and self-motivated. Considerable reading of research and publications, as outlined in this folio, supported the update of these assumptions relative to teaching and learning. ITSM Discipline staff were required to quickly and naturally change their teaching styles and communication of values to engage with the emergent ITSM Discipline learning environment and pedagogy, and each new teaching situation. From a student perspective such assumptions meant students needed to move from reliance upon teaching and prescriptive transmission of information to a self-motivated and more self-actualising and reflective set of strategies for learning. In constructing this folio, after the introductory chaperts, there are two distinct component parts; • firstly, a Descriptive Meta analysis (Chapter Three) that draws together several of my peer reviewed professional writings and observations that document the progression of the ITSM Discipline learning environment evolution during the period 1997/8 to 2003. As the learning environment designer and discipline leader, my observations and published papers provide insight into the considerations that are required when providing an active, flexible and multi-modal learning environment for students and teachers; and • secondly, a Dissertation (Chapter Four), as a content analysis of a learning skills inventory data collection, collected by the ITSM Discipline in the 2002 Swinburne Lilydale academic year, where students were encouraged to complete reflective journal entries via the ITSM Discipline virtual learning guide subject web-site. That data collection included all students in a majority of subjects supported by the ITSM Discipline for both semesters one and two 2002. The original purpose of the journal entries was to have students reflectively involved in assessing their learning skills and approaches to learning. Such perceptions were tested using a well-known metric, the ‘learning skills inventory’ (Knowles, 1975), augmented with a short reflective learning approach narrative. The journal entries were used by teaching staff originally and then made available to researchers as a desensitised data in 2003 for statistical and content analysis relative to student learning skills and approaches. The findings of my research support a view of the student and teacher enculturation as utilitarian, dependent and pragmatically self-motivated. This, I argue, shows little sign of abatement in the early part of the 21st Century. My observation suggests that this is also independent of the pedagogical and educational philosophy debate or practice as currently presented. As much as the self-actualising, self-motivated learning environment can be justified philosophically, the findings observed from this research, reported in this folio, cannot. Part of the reason for this originates from the debate by educational researchers as to the relative merits of liberal and vocational philosophies for education combined with the recent introduction of information and communication technologies, and commodification of higher education. Challenging students to be participative and active learners, as proposed by educationalists Meyers and Jones (1993), i.e. self-motivated and self-actualising learners, has proved to be problematic. This, I will argue, will require a change to a variable/s (not yet identified) of higher education enculturation on multiple fronts, by students, teachers and society in order to bridge the gap. This research indicates that tertiary educators and educational researchers should stop thinking simplistically of constructivist and/or technology-enabled approaches, students learning choices and teachers teaching choices. Based on my research I argue for a far more holistic set of explanations of student and staff expectations and behaviour, and therefore pedagogy that supports those expectations.

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Background: Individual variations in the use of the species niche are an important component of diversity in trophic interactions. A challenge in testing consistency of individual foraging strategy is the repeated collection of information on the same individuals.

Methodology/Principal Findings: The foraging strategies of sympatric fur seals (Arctocephalus gazella and A. tropicalis) were examined using the stable isotope signature of serially sampled whiskers. Most whiskers exhibited synchronous delta C-13 and delta N-15 oscillations that correspond to the seal annual movements over the long term (up to 8 years). delta C-13 and delta N-15 values were spread over large ranges, with differences between species, sexes and individuals. The main segregating mechanism operates at the spatial scale. Most seals favored foraging in subantarctic waters (where the Crozet Islands are located) where they fed on myctophids. However, A. gazella dispersed in the Antarctic Zone and A. tropicalis more in the subtropics. Gender differences in annual time budget shape the seal movements. Males that do not perform any parental care exhibited large isotopic oscillations reflecting broad annual migrations, while isotopic values of females confined to a limited foraging range during lactation exhibited smaller changes. Limited inter-individual isotopic variations occurred in female seals and in male A. tropicalis. In contrast, male A. gazella showed large inter-individual variations, with some males migrating repeatedly to high-Antarctic waters where they fed on krill, thus meaning that individual specialization occurred over years.

Conclusions/Significance: Whisker isotopic signature yields unique long-term information on individual behaviour that integrates the spatial, trophic and temporal dimensions of the ecological niche. The method allows depicting the entire realized niche of the species, including some of its less well-known components such as age-, sex-, individual- and migration-related changes. It highlights intrapopulation heterogeneity in foraging strategies that could have important implications for likely demographic responses to environmental variability.

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1. Maintaining a high and stable body temperature is often critical for female ectotherms during reproduction. Yet this strategy may be energetically costly, and therefore challenging, during this period of already high-energy demand. 2. Here, the 6-week deployment of tri-axial accelerometers (n = 6) on a marine ectotherm, the loggerhead turtle (Caretta caretta), reproducing at the northern limit of the species’ breeding range (i.e. in a thermally dynamic environment) revealed the behavioural mechanisms underlying its energy management strategy during the breeding season. 3. The estimated activity levels of female loggerheads using overall dynamic body acceleration (ODBA) were high during the breeding season, suggesting that marine turtles may not be able to remain inactive for long periods in the same manner as terrestrial ectotherms, because of the thermally dynamic nature of their environment. 4. However, activity levels were not constant throughout the season, being impacted by both ambient water temperature and female reproductive status. In cold water at the beginning of the nesting season, high levels of activity suggested that females behaviourally thermoregulated by seeking out warm water patches along the shoreline. Interactions with male turtles (courtship and/or avoidance) may also explain this high level of activity. As sea temperatures warmed up and the amount of energy devoted to reproduction probably increased, the turtles spent more time resting during long sequential flat-bottomed dives, and reduced any unnecessary locomotory activity. 5. Turtles may therefore adjust their activity patterns in response to seasonal variations in abiotic (i.e. ambient temperature) and biotic (i.e. reproductive status) factors. This may help minimize activity-linked metabolic rate and maximize reproductive output over a season while breeding in thermally dynamic environments. 6. A mechanistic model gave support to these empirical results. The model revealed that actively maintaining high and stable body temperature is of clear benefit to female turtles at temperate breeding sites. While energetically costly, such active thermoregulatory behaviour may speed up egg maturation, allowing turtles to initiate nesting earlier in the season, and hence maximize reproductive output.

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Although many approaches have been employed to enhance thermal stability of PVA, developing a facile and effective strategy remains highly attractive. Herein, we demonstrate a highly effective approach to strikingly improve thermal stability of PVA by selecting the types of multiamines molecules to tune the hydrogen-bond crosslink density. Results show that only adding 0.5 wt% of 2,4,5,6-tetraaminopyrimidine can make the initial degradation temperature (Ti) and maximum degradation temperature (Tmax) of PVA increase by ~55 °C and 98 °C due to the formation of 3D physically H-bond crosslinked network, resulting in superior thermal stability property to those of PVA nanocomposites. Moreover, thermal stability strongly depends on the H-bond crosslink density, and Ti and Tmax basically obey the linear hydrogen-bond relations despite some deviations. This work opens up a novel biological methodology for creating thermally stable polymeric materials.

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The presented work deals with the calibration of a 2D numerical model for the simulation of long term bed load transport. A settled basin along an alpine stream was used as a case study. The focus is to parameterise the used multi fractional transport model such that a dynamically balanced behavior regarding erosion and deposition is reached. The used 2D hydrodynamic model utilizes a multi-fraction multi-layer approach to simulate morphological changes and bed load transport. The mass balancing is performed between three layers: a top mixing layer, an intermediate subsurface layer and a bottom layer. Using this approach bears computational limitations in calibration. Due to the high computational demands, the type of calibration strategy is not only crucial for the result, but as well for the time required for calibration. Brute force methods such as Monte Carlo type methods may require a too large number of model runs. All here tested calibration strategies used multiple model runs utilising the parameterization and/or results from previous run. One concept was to reset to initial bed elevations after each run, allowing the resorting process to convert to stable conditions. As an alternative or in combination, the roughness was adapted, based on resulting nodal grading curves, from the previous run. Since the adaptations are a spatial process, the whole model domain is subdivided in homogeneous sections regarding hydraulics and morphological behaviour. For a faster optimization, the adaptation of the parameters is made section wise. Additionally, a systematic variation was done, considering results from previous runs and the interaction between sections. The used approach can be considered as similar to evolutionary type calibration approaches, but using analytical links instead of random parameter changes.

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Most of water distribution systems (WDS) need rehabilitation due to aging infrastructure leading to decreasing capacity, increasing leakage and consequently low performance of the WDS. However an appropriate strategy including location and time of pipeline rehabilitation in a WDS with respect to a limited budget is the main challenge which has been addressed frequently by researchers and practitioners. On the other hand, selection of appropriate rehabilitation technique and material types is another main issue which has yet to address properly. The latter can affect the environmental impacts of a rehabilitation strategy meeting the challenges of global warming mitigation and consequent climate change. This paper presents a multi-objective optimization model for rehabilitation strategy in WDS addressing the abovementioned criteria mainly focused on greenhouse gas (GHG) emissions either directly from fossil fuel and electricity or indirectly from embodied energy of materials. Thus, the objective functions are to minimise: (1) the total cost of rehabilitation including capital and operational costs; (2) the leakage amount; (3) GHG emissions. The Pareto optimal front containing optimal solutions is determined using Non-dominated Sorting Genetic Algorithm NSGA-II. Decision variables in this optimisation problem are classified into a number of groups as: (1) percentage proportion of each rehabilitation technique each year; (2) material types of new pipeline for rehabilitation each year. Rehabilitation techniques used here includes replacement, rehabilitation and lining, cleaning, pipe duplication. The developed model is demonstrated through its application to a Mahalat WDS located in central part of Iran. The rehabilitation strategy is analysed for a 40 year planning horizon. A number of conventional techniques for selecting pipes for rehabilitation are analysed in this study. The results show that the optimal rehabilitation strategy considering GHG emissions is able to successfully save the total expenses, efficiently decrease the leakage amount from the WDS whilst meeting environmental criteria.

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Trabalho apresentado no Congresso Nacional de Matemática Aplicada à Indústria, 18 a 21 de novembro de 2014, Caldas Novas - Goiás

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The main objective of this Thesis is to analyze Customer Intimacy Strategy in B2B technology businesses in Colombia and the variables that have a direct relationship with it like perception, trust and networking. And how a Customer Intimacy Strategy can affect a company to achieve positive or negative results in an operation, in terms of business opportunities, relations and profitable and sustainable sales if properly managed or mismanaged. With a population of almost 50 million people, GDP average growth of 4.22%(considering 2013 up to 2017), a strategic geographic location in Latin America close to the middle of the region with direct access to the Pacific and Atlantic oceans, on the verge to reach a peace agreement ending its long time social and security conflict with the local guerrillas, Colombia is a country with a stable economic present and promising future. But despite the appealing business landscape and opportunities both in number and size, it is a developing economy where firms who are willing to run a startup or who currently have B2B technology operations in this country will find out that uncertainty and mistrust are two of the most critical variables that need to be overcome in order to achieve success. Their relevance will vary from one region to another, but will still be considered of most importance throughout the country. This matter is highly important to B2B technology businesses in Colombia because few firms are aware of the importance of customer intimacy strategy, believing that it is just a matter of social relationships and not considering the diverse number of variables such us perception, trust and networking that compose it. Customer intimacy strategy at the end becomes the main and most relevant source of sales in a B2B technology environment in Colombia.

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This work presents the application of a multiobjective evolutionary algorithm (MOEA) for optimal power flow (OPF) solution. The OPF is modeled as a constrained nonlinear optimization problem, non-convex of large-scale, with continuous and discrete variables. The violated inequality constraints are treated as objective function of the problem. This strategy allows attending the physical and operational restrictions without compromise the quality of the found solutions. The developed MOEA is based on the theory of Pareto and employs a diversity-preserving mechanism to overcome the premature convergence of algorithm and local optimal solutions. Fuzzy set theory is employed to extract the best compromises of the Pareto set. Results for the IEEE-30, RTS-96 and IEEE-354 test systems are presents to validate the efficiency of proposed model and solution technique.