921 resultados para Production planning


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This paper presents a novel method to rank map hypotheses by the quality of localization they afford. The highest ranked hypothesis at any moment becomes the active representation that is used to guide the robot to its goal location. A single static representation is insufficient for navigation in dynamic environments where paths can be blocked periodically, a common scenario which poses significant challenges for typical planners. In our approach we simultaneously rank multiple map hypotheses by the influence that localization in each of them has on locally accurate odometry. This is done online for the current locally accurate window by formulating a factor graph of odometry relaxed by localization constraints. Comparison of the resulting perturbed odometry of each hypothesis with the original odometry yields a score that can be used to rank map hypotheses by their utility. We deploy the proposed approach on a real robot navigating a structurally noisy office environment. The configuration of the environment is physically altered outside the robots sensory horizon during navigation tasks to demonstrate the proposed approach of hypothesis selection.

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Purpose To establish whether the use of a passive or active technique of planning target volume (PTV) definition and treatment methods for non-small cell lung cancer (NSCLC) deliver the most effective results. This literature review assesses the advantages and disadvantages in recent studies of each, while assessing the validity of the two approaches for planning and treatment. Methods A systematic review of literature focusing on the planning and treatment of radiation therapy to NSCLC tumours. Different approaches which have been published in recent articles are subjected to critical appraisal in order to determine their relative efficacy. Results Free-breathing (FB) is the optimal method to perform planning scans for patients and departments, as it involves no significant increase in cost, workload or education. Maximum intensity projection (MIP) is the fastest form of delineation, however it is noted to be less accurate than the ten-phase overlap approach for computed tomography (CT). Although gating has proven to reduce margins and facilitate sparing of organs at risk, treatment times can be longer and planning time can be as much as 15 times higher for intensity modulated radiation therapy (IMRT). This raises issues with patient comfort and stabilisation, impacting on the chance of geometric miss. Stereotactic treatments can take up to 3 hours to treat, along with increases in planning and treatment, as well as the additional hardware, software and training required. Conclusion Four-dimensional computed tomography (4DCT) is superior to 3DCT, with the passive FB approach for PTV delineation and treatment optimal. Departments should use a combination of MIP with visual confirmation ensuring coverage for stage 1 disease. Stages 2-3 should be delineated using ten-phases overlaid. Stereotactic and gated treatments for early stage disease should be used accordingly; FB-IMRT is optimal for latter stage disease.

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This project is led by scientists in conservation decision appraisal and brings together a group of experts working across the Lake Eyre Basin (LEB). The LEB covers a sixth of Australia, with an array of globally significant natural values that are threatened by invasive plants, among other things. Managers at various levels are investing in attempts to control, contain and eradicate these invasive plant species, under severe time and resources limitations. To date there has been no basin-wide assessment of which weed management strategies and locations provide the best investments for maximising outcomes for biodiversity per unit cost. Further, there has been no assessment of the extent of ecosystem intactness that may be lost without effective invasive plant species management strategies. Given that there are insufficient resources to manage all invasive plant species everywhere, this information has the potential to improve current investment decisions. Here, we provide a prioritisation of invasive plant management strategies in the LEB. Prioritisation was based on cost-effectiveness for biodiversity benefits. We identify the key invasive plant species to target to protect ecosystem intactness across the bioregions of the LEB, the level of investment required and the likely reduction in invasive species dominance gained per dollar spent on each strategy. Our focus is on strategies that are technically and socially feasible and reduce the likelihood that high impact invasive plant species will dominate native ecosystems, and therefore change their form and function. The outputs of this work are designed to help guide decision-making and further planning and investment in weed management for the Basin. Experts in weed management, policy-making, community engagement, biodiversity and natural values of the Basin, attended a workshop and agreed upon 12 strategies to manage invasive plants. The strategies focused primarily on 10 weeds which were considered to have a high potential for broad, significant impacts on natural ecosystems in the next 50 years and for which feasible management strategies could be defined. Each strategy consisted of one or more supporting actions, many of which were spatially linked to IBRA (Interim Biogeographical Regionalisation of Australia) bioregions. The first strategy was an over-arching recommendation for improved mapping, information sharing, education and extension efforts in order to facilitate the more specific weed management strategies. The 10 more specific weed management strategies targeted the control and/or eradication of the following high-impact exotic plants: mesquite, parkinsonia, rubber vine, bellyache bush, cacti, mother of millions, chinee apple, athel pine and prickly acacia, as well as a separate strategy for eradicating all invasive plants from one key threatened ecological community, the GAB (Great Artesian Basin dependant) mound springs. Experts estimated the expected biodiversity benefit of each strategy as the reduction in area that an invasive plant species is likely to dominate in over a 50-year period, where dominance was defined as more than 30% coverage at a site. Costs were estimated in present day terms over 50 years largely during follow up discussions post workshop. Cost-effectiveness was then calculated for each strategy in each bioregion by dividing the average expected benefit by the average annual costs. Overall, the total cost of managing 12 invasive plant strategies over the next 50 years was estimated at $1.7 billion. It was estimated that implementation of these strategies would result in a reduction of invasive plant dominance by 17 million ha (a potential 32% reduction), roughly 14% of the LEB. If only targeting Weeds of National Significance (WONS), the total cost was estimated to be $113 million over the next 50 years. Over the next 50 years, $2.3 million was estimated to eradicate all invasive plant species from the Great Artesian Basin Mound Springs threatened ecological community. Prevention and awareness programs were another key strategy targeted across the Basin and estimated at $17.5 million in total over 50 years. The cost of controlling, eradicating and containing buffel grass were the most expensive, over $1.5 billion over 50 years; this strategy was estimated to result in a reduction in buffel grass dominance of a million ha in areas where this species is identified as an environmental problem. Buffel grass has been deliberately planted across the Basin for pasture production and is by far the most widely distributed exotic species. Its management is contentious, having economic value to many graziers while posing serious threats to biodiversity and sites of high cultural and conservation interest. The strategy for containing and locally eradicating buffel grass was a challenge to cost based on expert knowledge, possibly because of the dual nature of this species as a valued pastoral grass and environmental weed. Based on our conversations with experts, it appears that control and eradication programs for this species, in conservation areas, are growing rapidly and that information on the most cost-effective strategies for this species will continue to develop over time. The top five most cost-effective strategies for the entire LEB were for the management of: 1) parkinsonia, 2) chinee apple, 3) mesquite, 4) rubber vine and 5) bellyache bush. Chinee apple and mother of millions are not WONS and have comparatively small populations within the semi-arid bioregions of Queensland. Experts felt that there was an opportunity to eradicate these species before they had the chance to develop into high-impact species within the LEB. Prickly acacia was estimated to have one of the highest benefits, but the costs of this strategy were high, therefore it was ranked 7th overall. The buffel grass strategy was ranked the lowest (10th) in terms of cost effectiveness. The top five most cost-effective strategies within and across the bioregions were the management of: 1) parkinsonia in the Channel Country, 2) parkinsonia in the Desert Uplands, 3) mesquite in the Mitchell Grass Downs, 4) parkinsonia in the Mitchell Grass Downs, and 5) mother of millions in the Desert Uplands. Although actions for several invasive plant species like parkinsonia and prickly acacia were concentrated in the Queensland part of the LEB, the actions involved investing in containment zones to prevent the spread of these species into other states. In the NT and SA bioregions of the LEB, the management of athel pine, parkinsonia and cacti were the main strategies. While outside the scientific research goals of study, this work highlighted a number of important incidental findings that led us to make the following recommendations for future research and implementation of weed management in the Basin: • Ongoing stakeholder engagement, extension and participation is required to ensure this prioritisation effort has a positive impact in affecting on-ground decision making and planning. • Short term funding for weed management was identified as a major reason for failure of current efforts, hence future funding needs to be secure and ongoing. • Improved mapping and information sharing is essential to implement effective weed management. • Due to uncertainties in the outcomes and impacts of management options, strategies should be implemented as part of an adaptive management program. The information provided in this report can be used to guide investment for controlling high-impact invasive plant species for the benefits of biodiversity conservation. We do not present a final prioritisation of invasive plant strategies for the LEB, and we have not addressed the cultural, socio-economic or spatial components necessary for an implementation plan. Cost-effectiveness depends on the objectives used; in our case we used the intactness of ecosystems as a surrogate for expected biodiversity benefits, measured by the extent that each invasive plant species is likely to dominate in a bioregion. When other relevant factors for implementation are considered the priorities may change and some actions may not be appropriate in some locations. We present the costs, ecological benefits and cost-effectiveness of preventing, containing, reducing and eradicating the dominance of high impact invasive plants through realistic management actions over the next 50 years. In doing so, we are able to estimate the size of the weed management problem in the LEB and provide expert-based estimates of the likely outcomes and benefits of implementing weed management strategies. The priorities resulting from this work provide a prospectus for guiding further investment in management and in improving information availability.

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In recent years, the beauty leaf plant (Calophyllum Inophyllum) is being considered as a potential 2nd generation biodiesel source due to high seed oil content, high fruit production rate, simple cultivation and ability to grow in a wide range of climate conditions. However, however, due to the high free fatty acid (FFA) content in this oil, the potential of this biodiesel feedstock is still unrealized, and little research has been undertaken on it. In this study, transesterification of beauty leaf oil to produce biodiesel has been investigated. A two-step biodiesel conversion method consisting of acid catalysed pre-esterification and alkali catalysed transesterification has been utilized. The three main factors that drive the biodiesel (fatty acid methyl ester (FAME)) conversion from vegetable oil (triglycerides) were studied using response surface methodology (RSM) based on a Box-Behnken experimental design. The factors considered in this study were catalyst concentration, methanol to oil molar ratio and reaction temperature. Linear and full quadratic regression models were developed to predict FFA and FAME concentration and to optimize the reaction conditions. The significance of these factors and their interaction in both stages was determined using analysis of variance (ANOVA). The reaction conditions for the largest reduction in FFA concentration for acid catalysed pre-esterification was 30:1 methanol to oil molar ratio, 10% (w/w) sulfuric acid catalyst loading and 75 °C reaction temperature. In the alkali catalysed transesterification process 7.5:1 methanol to oil molar ratio, 1% (w/w) sodium methoxide catalyst loading and 55 °C reaction temperature were found to result in the highest FAME conversion. The good agreement between model outputs and experimental results demonstrated that this methodology may be useful for industrial process optimization for biodiesel production from beauty leaf oil and possibly other industrial processes as well.

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Subjective perceptions about a product affect consumer choice. Accordingly, acquiring the underlying demand characteristics that consumers find desirable is vital for firms planning future marketing strategies. However, the extent to which product-specific perceptions affect consumer choice is poorly understood. New agricultural standards for organic livestock were introduced in Japan in November 2005 and are expected to influence the market significantly. Choice modeling (CM) is used to explore how consumers evaluate the latent demands and conventional attributes (or tangible values) of organic milk. The results suggest that latent demands, along with socioeconomic characteristics and conventional attributes, provide strong incentives for consumers to move from the purchase of conventional milk to organic milk. The analysis indicates that latent demands reflecting the safeness of organic milk, the better taste of organic milk, the image of environmental friendliness in the production process, and the image of the health and comfort of the cows are important factors that influence consumers' purchasing decisions. However, each specific factor has a corresponding conventional tangible attribute that needs to be targeted in marketing strategy.

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Purpose – Rapid urbanisation, fragmented governance and recurrent flooding complicates resolution of DKI Jakarta’s chronic housing shortage. Failure to effectively implement planning decisionmaking processes poses potential human rights violations. Contemporary planning policy requires the relocation of households living in floodplains within fifteen metres of DKI Jakarta’s main watercourses; further constraining land availability and potentially requiring increased densification. The purpose of this paper is to re-frame planning decision-making to address risks of flooding and to increase community resilience. Design/methodology/approach – This paper presents a preliminary scoping study for a technologically enhanced participatory planning method, incorporating synthesis of existing information on urbanisation, governance, and flood risk management in Jakarta. Findings – Responsibility for flood risk management in DKI Jakarta is fragmented both within and across administrative boundaries. Decision-making is further complicated by: limited availability of land use data; uncertainty as to the delineated extent of watercourses, floodplains, and flood modelling; unclear risk and liability for infrastructure investments; and technical literacy of both public and government participants. Practical implications – This research provides information to facilitate consultation with government entities tasked with re-framing planning processes to increase public participation. Social implications – Reduction in risk exposure amongst DKI Jakarta’s most vulnerable populations addresses issues of social justice.

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In recent years, a great deal has been written about the benefits and ethics of including young people in participative decision-making. This has been accompanied by a burgeoning interest in including their views in participatory planning exercises that has not always been realised in practice. Drawing on a detailed analysis of the perceptions of adults and young people involved in a participatory planning exercise on Australia‟s Gold Coast, we believe that there are two major hurdles to the „full‟ engagement of young people that are in some respects two sides of the same coin: the sometimes paternalistic perceptions and often dismissive attitude that many adults have towards the participation of young people; and the perceptions that young people may have of themselves and their subordinate place in an adult-dominated planning environment. Together, such views act to place limitations on the participation of young people because they set up unrealistic expectations for both adult and younger participants in terms of how and why young people participate, and what this participation should „look and feel‟ like. In this paper, through the metaphor of boxes, we propose a number of issues that should be addressed when involving young people in participatory planning processes to ensure the most from their participation for all involved.

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Significant lifestyle and demographic changes in Queensland are beginning to alter the landscape of regional transport planning. In 2006, Queensland Transport undertook a study to understand the implications of these changes on the transport planning task in regional Queensland. The study focused on the current travel characteristics of three Local Government Areas in the Wide Bay Burnett Region. Hervey Bay City represented the ‘sea change’ phenomenon; Wondai Shire represented the growing ‘tree change’ lifestyle; and Monto Shire represented communities which were either experiencing limited change or a decrease in population. The results of this research will be used to inform long term integrated regional transport planning in the region.

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Enterprise Resource Planning (ERP) software typically takes the form of a package that is licensed for use to those in a client organisation and is sold as being able to automate a wide range of processes within organisations. ERP packages have become an important feature of information and communications technology (ICT) infrastructures in organizations. However, a number of highly publicised failures have been associated with the ERP packages too. For example: Hershey, Aero Group and Snap-On have blamed the implementation of ERP packages for negative impacts upon earnings (Scott and Vessey 2000); Cadbury Schweppes implemented plans to fulfil 250 orders where normally they would fulfil 1000 due to the increased complexity and the need to re-train staff post implementation (August 1999) and FoxMeyer drug company’s implementation of an ERP package has been argued to have lead to bankruptcy proceedings resulting in litigation against SAP, the software vendor in question (Bicknell 1998). Some have even rejected a single vendor approach outright (Light et. al. 2001). ERP packages appear to work for some and not for others, they contain contradictions. Indeed, if we start from the position that technologies do not provide their own explanation, then we have to consider the direction of a technological trajectory and why it moves in one way rather than another (Bijker and Law 1994). In other words, ERP appropriation cannot be predetermined as a success, despite the persuasive attempts of vendors via their websites and other marketing channels. Moreover, just because ERP exists, we cannot presume that all will appropriate it in the same fashion, if at all. There is more to the diffusion of innovations than stages of adoption and a simple demarcation between adoption and rejection. The processes that are enacted in appropriation need to be conceptualised as a site of struggle, political and imbued with power (Hislop et. al. 2000; Howcroft and Light, 2006). ERP appropriation and rejection can therefore be seen as a paradoxical phenomenon. In this paper we examine these contradictions as a way to shed light on the presence and role of inconsistencies in ERP appropriation and rejection. We argue that much of the reasoning associated with ERP adoption is pro-innovation biased and that deterministic models of the diffusion of innovations such as Rogers (2003), do not adequately take account of contradictions in the process. Our argument is that a better theoretical understanding of these contradictions is necessary to underpin research and practice in this area. In the next section, we introduce our view of appropriation. Following this is an outline of the idea of contradiction, and the strategies employed to ‘cope’ with this. Then, we introduce a number of reasons for ERP adoption and identify their inherent contradictions using these perspectives. From this discussion, we draw a framework, which illustrates how the interpretive flexibility of reasons to adopt ERP packages leads to contradictions which fuel the enactment of appropriation and rejection.

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Enterprise Resource Planning (ERP) systems are integrated enterprise-wide standard information systems that automate all aspects of an organisations’ business processes. The ERP philosophy is that business systems incorporating sales, marketing, manufacturing, distribution, personnel and finance modules can be supported by a single integrated system with all of the company’s data captured in a central database. The ERP packages of vendors such as SAP, Baan, J.D. Edwards and Intentia represent more than a common systems platform for a business. They prescribe information blueprints of how organisation’s business processes should operate. In this paper, the scale and strategic importance of ERP systems is identified and the problem of ERP implementation is defined. Five company examples are analysed using a Critical Success Factors (CSFs) theoretical framework. The paper offers a framework for managers which provides the basis for developing an ERP implementation strategy. The case analysis identifies different approaches to ERP implementation, highlights the critical role of legacy systems in influencing the implementation process, and identifies the importance of business process change and software configuration in addition to factors already cited in the literature such as top management support and communication. The implications of the results and future research opportunities are outlined.

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ABSTRACT A rapidly changing business environment and legacy IT problems has resulted in many organisations implementing standard package solutions. This 'common systems' approach establishes a common IT and business process infrastructure within organisations and its increasing dominance raises several important strategic issues. These are to what extent do common systems impose common business processes and management systems on competing firms, and what is the source of competitive advantage if the majority of firms employ almost identical information systems and business processes? A theoretical framework based on research into legacy systems and earlier IT strategy literature is used to analyse three case studies in the manufacturing, chemical and IT industries. It is shown that the organisations are treating common systems as the core of their organisations' abilities to manage business transactions. To achieve competitive advantage they are clothing these common systems with information systems designed to capture information about competitors, customers and suppliers, and to provide a basis for sharing knowledge within the organisation and ultimately with economic partners. The importance of these approaches to other organisations and industries is analysed and an attempt is made at outlining the strategic options open to firms beyond the implementation of common business systems.

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Abstract - Enterprise Resource Planning (ERP) software has become the dominant strategic platform for supporting enterprise-wide business processes. However, single vendor ERP software systems have been criticised for not meeting specific organisation and industry requirements. An alternative approach ‘Best of Breed (BoB)’, integrates components of software from multiple standard package vendors, and in some cases custom components. The objective is to develop enterprise systems that are more closely aligned with the requirements of an organisation. Although this approach may not be common at present it is likely to grow in importance due to business needs and technology advances such as the componentisation of ERP software. A case study analysis of a BoB implementation at a global entertainment's company is used as a platform for the discussion of the issues associated with this strategy and a comparison is made with the single vendor ERP alternative. The analysis centres on the complexity of implementation, the differences in the levels of functionality and business fit and the maintenance requirements.

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Those in organisations tend to adopt new technologies as a way to improve their functions, reduce cost and attain best practices. Thus, technology promoters (or vendors) work along those lines in order to convince adopters to invest in those technologies and develop their own organisations profit in return. The possible resultant ‘conflicts of interest’ makes the study of reasons behind IT diffusion and adoption an interesting subject. In this paper we look at IT diffusion and adoption in terms of technology (system features), organisational aspects (firm level characteristics) and inter-organisational aspects (market dynamics) in order to see who might be the real beneficiaries of technology adoption. We use ERP packages as an example of an innovation that has been widely diffused and adopted for the last 10 years. We believe that our findings can be useful to those adopting ERP packages as it gives them a wider view of the situation.

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Supply chains are the core of most industrial networks in which your business operates. They provide the pipeline through which the products and services flow from supplier to customer across each element within the business activity system. Global supply chain relationships have become the basis for many industries with an international network of firms engaged in the supply of goods and services that must be produced to quality standards in one country and delivered just-in-time for assembly or integration into further production processes in another country, frequently many thousands of miles apart. This topic examines the nature of supply chain management and their role in strategic networking. The previous learning tasks have focused on having the correct internal mechanism to effectively manage the inputs and outputs of the organisation by implementing an effective and transparent management system. This learning task takes a look at how management intent strategy and innovation are used to measure the external factors that influence the overall performance of the organisation and develop new strategies by understanding the business cycle and the people within your market environment.

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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