295 resultados para Inside-Outside Algorithm
Resumo:
The work presented in this report is aimed to implement a cost-effective offline mission path planner for aerial inspection tasks of large linear infrastructures. Like most real-world optimisation problems, mission path planning involves a number of objectives which ideally should be minimised simultaneously. Understandably, the objectives of a practical optimisation problem are conflicting each other and the minimisation of one of them necessarily implies the impossibility to minimise the other ones. This leads to the need to find a set of optimal solutions for the problem; once such a set of available options is produced, the mission planning problem is reduced to a decision making problem for the mission specialists, who will choose the solution which best fit the requirements of the mission. The goal of this work is then to develop a Multi-Objective optimisation tool able to provide the mission specialists a set of optimal solutions for the inspection task amongst which the final trajectory will be chosen, given the environment data, the mission requirements and the definition of the objectives to minimise. All the possible optimal solutions of a Multi-Objective optimisation problem are said to form the Pareto-optimal front of the problem. For any of the Pareto-optimal solutions, it is impossible to improve one objective without worsening at least another one. Amongst a set of Pareto-optimal solutions, no solution is absolutely better than another and the final choice must be a trade-off of the objectives of the problem. Multi-Objective Evolutionary Algorithms (MOEAs) are recognised to be a convenient method for exploring the Pareto-optimal front of Multi-Objective optimization problems. Their efficiency is due to their parallelism architecture which allows to find several optimal solutions at each time
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Immigrant entrepreneurs tend to start businesses within their ethnic enclave (EE), as it is an integral part of their social and cultural context and the location where ethnic resources reside (Logan, Alba, & Stults, 2003). Ethnic enclaves can be seen as a form of geographic cluster, China Towns are exemplar EEs, easily identified by the clustering of Chinese restaurants and other ethnic businesses in one central location. Studies on EE thus far have neglected the life cycles stages of EE and its impact on the business experiences of the entrepreneurs. In this paper, we track the formation, growth and decline of an EE. We argue that EE is a special industrial cluster and as such it follows the growth conditions proposed by the cluster life cycle theory (Menzel & Fornahl, 2009). We report a mixed method study of Chinese Restaurants in South East Queensland. Based on multiple sources of data, we concluded that changes in government policies leading to a sharp increase of immigrant numbers from a distinctive culture group can lead to the initiation and growth of the EE. Continuous incoming of new immigrants and increase competition within the cluster mark the mature stage of the EE, making the growth condition more favourable “inside” the cluster. A decline in new immigrants from the same ethnic group and the increased competition within the EE may eventually lead to the decline of such an industrial cluster, thus providing more favorable condition for growth of business outside the cluster.
Resumo:
This paper presents a numerical model for understanding particle transport and deposition in metal foam heat exchangers. Two-dimensional steady and unsteady numerical simulations of a standard single row metal foam-wrapped tube bundle are performed for different particle size distributions, i.e. uniform and normal distributions. Effects of different particle sizes and fluid inlet velocities on the overall particle transport inside and outside the foam layer are also investigated. It was noted that the simplification made in the previously-published numerical works in the literature, e.g. uniform particle deposition in the foam, is not necessarily accurate at least for the cases considered here. The results highlight the preferential particle deposition areas both along the tube walls and inside the foam using a developed particle deposition likelihood matrix. This likelihood matrix is developed based on three criteria being particle local velocity, time spent in the foam, and volume fraction. It was noted that the particles tend to deposit near both front and rear stagnation points. The former is explained by the higher momentum and direct exposure of the particles to the foam while the latter only accommodate small particles which can be entrained in the recirculation region formed behind the foam-wrapped tubes.
Resumo:
A travel article about Helsinki exploring the city's design culture. I’M often told that I’m from Finland. Even those who’ve known me for years confuse it with my birthplace, which is, in fact, Iceland. I’m not sure why the two countries are mixed up in this way, but it might be that Iceland and Finland are, in a sense, the “other” Scandinavian nations – on different sides of the Nordic world, but in the mind joined as its outer borders...
Resumo:
A computationally efficient sequential Monte Carlo algorithm is proposed for the sequential design of experiments for the collection of block data described by mixed effects models. The difficulty in applying a sequential Monte Carlo algorithm in such settings is the need to evaluate the observed data likelihood, which is typically intractable for all but linear Gaussian models. To overcome this difficulty, we propose to unbiasedly estimate the likelihood, and perform inference and make decisions based on an exact-approximate algorithm. Two estimates are proposed: using Quasi Monte Carlo methods and using the Laplace approximation with importance sampling. Both of these approaches can be computationally expensive, so we propose exploiting parallel computational architectures to ensure designs can be derived in a timely manner. We also extend our approach to allow for model uncertainty. This research is motivated by important pharmacological studies related to the treatment of critically ill patients.
Resumo:
A number of factors are thought to increase the risk of serious psychiatric disorder, including a family history of mental health issues and/or childhood trauma. As a result, some mental health advocates argue for a pre-emptive approach that includes the use of powerful anti-psychotic medication with young people considered at-risk of developing bipolar disorder or psychosis. This controversial approach is enabled and, at the same time, obscured by medical discourses that speak of promoting and maintaining youth “wellbeing”, however, there are inherent dangers both to the pre-emptive approach and in its positioning within the discourse of wellbeing. This chapter critically engages with these dangers by drawing on research with “at-risk” children and young people enrolled in special schools for disruptive behaviour. The stories told by these highly diagnosed and heavily medicated young people act as a cautionary tale to counter the increasingly common perception that pills and “Dr Phil’s” can cure social ills.
Resumo:
Stepping Outside the Circle was a practice-based research project focussed on creating a professional reflection framework for creative facilitators working within the community, education, corporate and health and wellbeing sectors. Underpinned by theories of critical reflection, transformative learning, reflexivity and agency, this study explored the potential benefits of multimodal inquiry processes, adapting existing reflective practice models for the unique requirements of creative facilitation contexts. Through application of the key findings from this research, synthesised in a practitioner resource, it is hoped that individual practitioners and creative organisations may develop their understanding of evaluation strategies, self- reflexivity, professional sustainability and practitioner self-care.
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Network Real-Time Kinematic (NRTK) is a technology that can provide centimeter-level accuracy positioning services in real time, and it is enabled by a network of Continuously Operating Reference Stations (CORS). The location-oriented CORS placement problem is an important problem in the design of a NRTK as it will directly affect not only the installation and operational cost of the NRTK, but also the quality of positioning services provided by the NRTK. This paper presents a Memetic Algorithm (MA) for the location-oriented CORS placement problem, which hybridizes the powerful explorative search capacity of a genetic algorithm and the efficient and effective exploitative search capacity of a local optimization. Experimental results have shown that the MA has better performance than existing approaches. In this paper we also conduct an empirical study about the scalability of the MA, effectiveness of the hybridization technique and selection of crossover operator in the MA.
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Over the past twenty years the contemporary art world has seen a significant shift in the modes and structures of connection between work and its audiences. This shift is termed by Irit Rogoff, amongst others, as an ‘educational turn’. The turn has been described as the eruption of discussions and investigations, inside and outside of institutions, that interrupt the presumed power hierarchies and bureaucratised systems of both art and education. This essay was written to accompany artist/curator Kym Maxwell's exhibition project, 'Uneducated', exploring these ideas. It was held at the Counihan Gallery in Melbourne, 2014.
Resumo:
Extracting frequent subtrees from the tree structured data has important applications in Web mining. In this paper, we introduce a novel canonical form for rooted labelled unordered trees called the balanced-optimal-search canonical form (BOCF) that can handle the isomorphism problem efficiently. Using BOCF, we define a tree structure guided scheme based enumeration approach that systematically enumerates only the valid subtrees. Finally, we present the balanced optimal search tree miner (BOSTER) algorithm based on BOCF and the proposed enumeration approach, for finding frequent induced subtrees from a database of labelled rooted unordered trees. Experiments on the real datasets compare the efficiency of BOSTER over the two state-of-the-art algorithms for mining induced unordered subtrees, HybridTreeMiner and UNI3. The results are encouraging.
Resumo:
This paper presents an algorithm for mining unordered embedded subtrees using the balanced-optimal-search canonical form (BOCF). A tree structure guided scheme based enumeration approach is defined using BOCF for systematically enumerating the valid subtrees only. Based on this canonical form and enumeration technique, the balanced optimal search embedded subtree mining algorithm (BEST) is introduced for mining embedded subtrees from a database of labelled rooted unordered trees. The extensive experiments on both synthetic and real datasets demonstrate the efficiency of BEST over the two state-of-the-art algorithms for mining embedded unordered subtrees, SLEUTH and U3.
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During the last decade 'prostitution' has been characterised as a 'social problem' throughout rural and regional New South Wales. As we show here, the urban-centric nature of popular and official discourses of prostitution have inadvertently allowed for the development of regulatory positions which have negatively impacted sex workers in rural and regional communities and lead to conflict among sectors of the rural sex industry and between the sex industry and community activists. In addition to examining the problematisation of sex work in rural New South Wales, this paper sets out to understand why rural sex work has historically lacked visibility in popular and scholarly discourses. We provide an overview of the distinctive organisational aspects of the sex industry in rural contexts. Evidence for our assertions is largely derived from primary interview data collected from sex industry workers based in rural New South Wales. The paper represents the first attempt in the research literature on prostitution to understand sex work as a rural phenomenon.
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A home embodies a sensorial space that is layered with personal memories and traces of history. The success of a home in providing a strong sense of place depends on various factors such as geographical location, climatic conditions, and occupants’ world-views and perceptions. This paper explores Muslims’ perceptions of privacy, modesty and hospitality within their homes through their lived experiences. This case study focuses on three Muslim families living in Australian designed homes within the same suburb of Brisbane, Australia. The study provides prefatory insight into the ways in which these families perform their daily activities and entertain their guests without jeopardizing their privacy needs. The study examines the significance of modesty in the design of Muslim homes as a means by which family members are able to achieve optimum privacy while simultaneously extending hospitality to guests inside and outside their homes. The findings of this study provide opportunities too, for expanding research into culturally adaptable housing systems to help meet the changing needs of Australian multicultural society.
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Parent–subsidiary relationships are commonplace nowadays, yet surprisingly there is a paucity of research analysing their dynamics over time. This paper presents a (longitudinal) case study, illuminating the dynamics implicated when a UK chemicals company imposed its systems and rules on a new subsidiary. Drawing on observations from a longitudinal case study (from 1993 to 2001), the study considers: (1) the extent to which a parent imposes its (management accounting) systems,rules and procedures on a subsidiary; (2) the role which (local) political, cultural and institutional factors in a subsidiary play in shaping the dynamics of such change implementation; (3) how new systems and practices become accepted and take root as values and beliefs and how they supplement earlier norms? The study provides insight for the questions above, and draws on institutional theories and a power mobilisation framework to assist in the interpretation of observations. We find that the operations of the subsidiary company are influenced by inter-related forces, both inside and outside the organisation encompassing issues of power, politics and culture. As such, existing institutions in a subsidiary organisation are influenced, sustained, and changed by the socio-economic context in which the subsidiary is located. Organisational practices designed to secure external legitimacy are not however always symbolic and decoupled from internal operations
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The MOCVD assisted formation of nested WS2 inorganic fullerenes (IF-WS2) was performed by enhancing surface diffusion with iodine, and fullerene growth was monitored by taking TEM snapshots of intermediate products. The internal structure of the core-shell nanoparticles was studied using scanning electron microscopy (SEM) after cross-cutting with a focused ion beam (FIB). Lamellar reaction intermediates were found occluded in the fullerene particles. In contrast to carbon fullerenes, layered metal chalcogenides prefer the formation of planar, plate-like structures where the dangling bonds at the edges are stabilized by excess S atoms. The effects of the reaction and annealing temperatures on the composition and morphology of the final product were investigated, and the strength of the WS2 shell was measured by intermittent contact-mode AFM. The encapsulated lamellar structures inside the hollow spheres may lead to enhanced tribological activities.