906 resultados para lot sizing and scheduling


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In cooperative communication systems, several wireless communication terminals collaborate to form a virtual-multiple antenna array system and exploit the spatial diversity to achieve a better performance. This thesis proposes a practical slotted protocol for cooperative communication systems with half-duplex single antennas. The performance of the proposed slotted cooperative communication protocol is evaluated in terms of the pairwise error probability and the bit error rate. The proposed protocol achieves the multiple-input single-output performance bound with a novel relay ordering and scheduling strategy.

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This paper aims to evaluate the brand value of property in subdivision developments in the Bangkok Metropolitan Region (BMR), Thailand. The result has been determined by the application of a hedonic price model. The development of the model is developed based on a sample of 1,755 property sales during the period of 1992-2010 in eight zones of the BMR. The results indicate that the use of a semi-logarithmic model has stronger explanatory power and is more reliable. Property price increases 12.90% from the branding. Meanwhile, the price annually increases 2.96%; lot size and dwelling area have positive impacts on the price. In contrast, duplexes and townhouses have a negative impact on the price compared to single detached houses. Moreover, the price of properties which are located outside the Bangkok inner city area is reduced by 21.26% to 43.19%. These findings also contribute towards a new understanding of the positive impact of branding on the property price in the BMR. The result is useful for setting selling prices for branded and unbranded properties, and the model could provide a reference for setting property prices in subdivision developments in the BMR.

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Global awareness for cleaner and renewable energy is transforming the electricity sector at many levels. New technologies are being increasingly integrated into the electricity grid at high, medium and low voltage levels, new taxes on carbon emissions are being introduced and individuals can now produce electricity, mainly through rooftop photovoltaic (PV) systems. While leading to improvements, these changes also introduce challenges, and a question that often rises is ‘how can we manage this constantly evolving grid?’ The Queensland Government and Ergon Energy, one of the two Queensland distribution companies, have partnered with some Australian and German universities on a project to answer this question in a holistic manner. The project investigates the impact the integration of renewables and other new technologies has on the physical structure of the grid, and how this evolving system can be managed in a sustainable and economical manner. To aid understanding of what the future might bring, a software platform has been developed that integrates two modelling techniques: agent-based modelling (ABM) to capture the characteristics of the different system units accurately and dynamically, and particle swarm optimization (PSO) to find the most economical mix of network extension and integration of distributed generation over long periods of time. Using data from Ergon Energy, two types of networks (3 phase, and Single Wired Earth Return or SWER) have been modelled; three-phase networks are usually used in dense networks such as urban areas, while SWER networks are widely used in rural Queensland. Simulations can be performed on these networks to identify the required upgrades, following a three-step process: a) what is already in place and how it performs under current and future loads, b) what can be done to manage it and plan the future grid and c) how these upgrades/new installations will perform over time. The number of small-scale distributed generators, e.g. PV and battery, is now sufficient (and expected to increase) to impact the operation of the grid, which in turn needs to be considered by the distribution network manager when planning for upgrades and/or installations to stay within regulatory limits. Different scenarios can be simulated, with different levels of distributed generation, in-place as well as expected, so that a large number of options can be assessed (Step a). Once the location, sizing and timing of assets upgrade and/or installation are found using optimisation techniques (Step b), it is possible to assess the adequacy of their daily performance using agent-based modelling (Step c). One distinguishing feature of this software is that it is possible to analyse a whole area at once, while still having a tailored solution for each of the sub-areas. To illustrate this, using the impact of battery and PV can have on the two types of networks mentioned above, three design conditions can be identified (amongst others): · Urban conditions o Feeders that have a low take-up of solar generators, may benefit from adding solar panels o Feeders that need voltage support at specific times, may be assisted by installing batteries · Rural conditions - SWER network o Feeders that need voltage support as well as peak lopping may benefit from both battery and solar panel installations. This small example demonstrates that no single solution can be applied across all three areas, and there is a need to be selective in which one is applied to each branch of the network. This is currently the function of the engineer who can define various scenarios against a configuration, test them and iterate towards an appropriate solution. Future work will focus on increasing the level of automation in identifying areas where particular solutions are applicable.

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Supercapacitors are increasingly used as short term energy storage elements in distributed generation systems. The traditional approach in integrating them to the main system is the use of interfacing dc-dc converters which introduce additional costs and power losses. This paper therefore, presents a novel direct integration scheme for supercapacitors and thereby eliminates associated costs and power losses of interfacing converters. The idea is simply to replace ordinary capacitors of three-level flying-capacitor rectifiers with supercapacitors and operate them under variable voltage conditions. An analysis on the reduction of power losses by the proposed system is presented. Furthermore, supercapacitor sizing and implementation issues such as effects of the variable voltage operation and resistive behavior of supercapacitors at high frequencies are also discussed. Simulation results are presented to verify the efficacy of the proposed system in suppressing short term power fluctuations in wind generation system.

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Resource assignment and scheduling is a difficult task when job processing times are stochastic, and resources are to be used for both known and unknown demand. To operate effectively within such an environment, several novel strategies are investigated. The first focuses upon the creation of a robust schedule, and utilises the concept of strategically placed idle time (i.e. buffering). The second approach introduces the idea of maintaining a number of free resources at each time, and culminates in another form of strategically placed buffering. The attraction of these approaches is that they are easy to grasp conceptually, and mimic what practitioners already do in practice. Our extensive numerical testing has shown that these techniques ensure more prompt job processing, and reduced job cancellations and waiting time. They are effective in the considered setting and could easily be adapted for many real life problems, for instance those in health care. This article has more importantly demonstrated that integrating the two approaches is a better strategy and will provide an effective stochastic scheduling approach.

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In the mining optimisation literature, most researchers focused on two strategic-level and tactical-level open-pit mine optimisation problems, which are respectively termed ultimate pit limit (UPIT) or constrained pit limit (CPIT). However, many researchers indicate that the substantial numbers of variables and constraints in real-world instances (e.g., with 50-1000 thousand blocks) make the CPIT’s mixed integer programming (MIP) model intractable for use. Thus, it becomes a considerable challenge to solve the large scale CPIT instances without relying on exact MIP optimiser as well as the complicated MIP relaxation/decomposition methods. To take this challenge, two new graph-based algorithms based on network flow graph and conjunctive graph theory are developed by taking advantage of problem properties. The performance of our proposed algorithms is validated by testing recent large scale benchmark UPIT and CPIT instances’ datasets of MineLib in 2013. In comparison to best known results from MineLib, it is shown that the proposed algorithms outperform other CPIT solution approaches existing in the literature. The proposed graph-based algorithms leads to a more competent mine scheduling optimisation expert system because the third-party MIP optimiser is no longer indispensable and random neighbourhood search is not necessary.

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With new national targets for patient flow in public hospitals designed to increase efficiencies in patient care and resource use, better knowledge of events affecting length of stay will support improved bed management and scheduling of procedures. This paper presents a case study involving the integration of material from each of three databases in operation at one tertiary hospital and demonstrates it is possible to follow patient journeys from admission to discharge. What is known about this topic? At present, patient data at one Queensland tertiary hospital are assembled in three information systems: (1) the Hospital Based Corporate Information System (HBCIS), which tracks patients from in-patient admission to discharge; (2) the Emergency Department Information System (EDIS) containing patient data from presentation to departure from the emergency department; and (3) Operation Room Management Information System (ORMIS), which records surgical operations. What does this paper add? This paper describes how a new enquiry tool may be used to link the three hospital information systems for studying the hospital journey through different wards and/or operating theatres for both individual and groups of patients. What are the implications for practitioners? An understanding of the patients’ journeys provides better insight into patient flow and provides the tool for research relating to access block, as well as optimising the use of physical and human resources.

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Virotherapy, the use of oncolytic properties of viruses for eradication of tumor cells, is an attractive strategy for treating cancers resistant to traditional modalities. Adenoviruses can be genetically modified to selectively replicate in and destroy tumor cells through exploitation of molecular differences between normal and cancer cells. The lytic life cycle of adenoviruses results in oncolysis of infected cells and spreading of virus progeny to surrounding cells. In this study, we evaluated different strategies for improving safety and efficacy of oncolytic virotherapy against human ovarian adenocarcinoma. We examined the antitumor efficacy of Ad5/3-Δ24, a serotype 3 receptor-targeted pRb-p16 pathway-selective oncolytic adenovirus, in combination with conventional chemotherapeutic agents. We observed synergistic activity in ovarian cancer cells when Ad5/3-Δ24 was given with either gemcitabine or epirubicin, common second-line treatment options for ovarian cancer. Our results also indicate that gemcitabine reduces the initial rate of Ad5/3-Δ24 replication without affecting the total amount of virus produced. In an orthotopic murine model of peritoneally disseminated ovarian cancer, combining Ad5/3-Δ24 with either gemcitabine or epirubicin resulted in greater therapeutic benefit than either agent alone. Another useful approach for increasing the efficacy of oncolytic agents is to arm viruses with therapeutic transgenes such as genes encoding prodrug-converting enzymes. We constructed Ad5/3-Δ24-TK-GFP, an oncolytic adenovirus encoding the thymidine kinase (TK) green fluorescent protein (GFP) fusion protein. This novel virus replicated efficiently on ovarian cancer cells, which correlated with increased GFP expression. Delivery of prodrug ganciclovir (GCV) immediately after infection abrogated viral replication, which might have utility as a safety switch mechanism. Oncolytic potency in vitro was enhanced by GCV in one cell line, and the interaction was not dependent on scheduling of the treatments. However, in murine models of metastatic ovarian cancer, administration of GCV did not add therapeutic benefit to this highly potent oncolytic agent. Detection of tumor progression and virus replication with bioluminescence and fluorescence imaging provided insight into the in vivo kinetics of oncolysis in living mice. For optimizing protocols for upcoming clinical trials, we utilized orthotopic murine models of ovarian cancer to analyze the effect of dose and scheduling of intraperitoneally delivered Ad5/3-Δ24. Weekly administration of Ad5/3-Δ24 did not significantly enhance antitumor efficacy over a single treatment. Our results also demonstrate that even a single intraperitoneal injection of only 100 viral particles significantly increased the survival of mice compared with untreated animals. Improved knowledge of adenovirus biology has resulted in creation of more effective oncolytic agents. However, with more potent therapy regimens an increase in unwanted side-effects is also possible. Therefore, inhibiting viral replication when necessary would be beneficial. We evaluated the antiviral activity of chlorpromazine and apigenin on adenovirus replication and associated toxicity in fresh human liver samples, normal cells, and ovarian cancer cells. Further, human xenografts in mice were utilized to evaluate antitumor efficacy, viral replication, and liver toxicity. Our data suggest that these agents can reduce replication of adenoviruses, which could provide a safety switch in case of replication-associated side-effects. In conclusion, we demonstrate that Ad5/3-Δ24 is a useful oncolytic agent for treatment of ovarian cancer either alone or in combination with conventional chemotherapeutic drugs. Insertion of genes encoding prodrug-converting enzymes into the genome of Ad5/3-Δ24 might not lead to enhanced antitumor efficacy with this highly potent oncolytic virus. As a safety feature, viral activity can be inhibited with pharmacological substances. Clinical trials are however needed to confirm if these preclinical results can be translated into efficacy in humans. Promising safety data seen here, and in previous publications suggest that clinical evaluation of the agent is feasible.

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Worldwide population growth and economic agglomeration is driving increasing urban density within larger metropolitan conurbations. Population growth and housing diversity and affordability issues in Queensland have seen an increasing demand for more diverse and higher density development. Under Queensland’s flexible planning regulatory provisions, a level of ‘medium’ to ‘high density’ is being achieved by a focus on fine-grained urban design, low scale development, lot diversity, and delivery of single dwelling products. This for Queensland (and Australia) has been an unprecedented innovation in urban and dwelling design. Dwellings are being delivered on lots with zero regulatory minimum sizes providing for a range of new products including ‘apartments on the ground’. This paper reviews recent and nascent demonstrations of EDQ’s fine-grained urbanism principles, identifiable with historical ‘vernacular suburbanism’. The paper introduces and defines a concept of a ‘natural density’ linking human scale built form with walkability. The paper challenges the notion that (sub)urban development, outside major city centres, needs to be of a higher scale to achieve density and diversity aspirations. ‘Natural density’ provides a means of achieving the increasing demand for more diverse and higher density development.

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6PANview[1] is a Wireless Sensor Network(WSN) monitoring system for 6LoWPAN/RPL networks which we developed as an overlay network for a WSN application. A monitoring system, while performing its operations for maintaining the health of the monitored network, must also be conscious of its impact on the application performance, and must strive to minimize this impact. To this end, we propose a centralized scheduling algorithm within 6PANview which non-intrusively analyzes application traffic arrival patterns at the base station, identifies network idle periods and schedules monitoring activities. The proposed algorithm finds those periodic sequences which are likely to have given rise to the pattern of arrivals seen at the base station. Parts of those sequences are then extended to coarsely predict future traffic and find epochs where low traffic is predicted, in order to schedule monitoring traffic or other activities at these times. We present simulation results for the proposed prediction and scheduling algorithm and its implementation as part of 6PANview. As an enhancement, we briefly talk about using 6PANview's overlay network architecture for distributed scheduling.

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FreeRTOS is an open-source real-time microkernel that has a wide community of users. We present the formal specification of the behaviour of the task part of FreeRTOS that deals with the creation, management, and scheduling of tasks using priority-based preemption. Our model is written in the Z notation, and we verify its consistency using the Z/Eves theorem prover. This includes a precise statement of the preconditions for all API commands. This task model forms the basis for three dimensions of further work: (a) the modelling of the rest of the behaviour of queues, time, mutex, and interrupts in FreeRTOS; (b) refinement of the models to code to produce a verified implementation; and (c) extension of the behaviour of FreeRTOS to multi-core architectures. We propose all three dimensions as benchmark challenge problems for Hoare's Verified Software Initiative.

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A block-structured adaptive mesh refinement (AMR) technique has been used to obtain numerical solutions for many scientific applications. Some block-structured AMR approaches have focused on forming patches of non-uniform sizes where the size of a patch can be tuned to the geometry of a region of interest. In this paper, we develop strategies for adaptive execution of block-structured AMR applications on GPUs, for hyperbolic directionally split solvers. While effective hybrid execution strategies exist for applications with uniform patches, our work considers efficient execution of non-uniform patches with different workloads. Our techniques include bin-packing work units to load balance GPU computations, adaptive asynchronism between CPU and GPU executions using a knapsack formulation, and scheduling communications for multi-GPU executions. Our experiments with synthetic and real data, for single-GPU and multi-GPU executions, on Tesla S1070 and Fermi C2070 clusters, show that our strategies result in up to a 3.23 speedup in performance over existing strategies.

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A Estratégia de Saúde da Família é um dos movimentos adotados pelo Brasil para o alcance da universalidade de acesso aos serviços de saúde em todos os níveis de assistência, integralidade da atenção, preservação da autonomia, igualdade da assistência, direito à informação e participação da comunidade. Com a reorganização da prática assistencial, são esperados maior resolubilidade, vínculo, acesso e continuidade da atenção, através de equipe multidisciplinar. Diversos autores vêm-se debruçando na análise da adequação desse modelo com o cuidado em saúde e sua contribuição para o bom êxito do atendimento aos indivíduos, aliviando seus sofrimentos. O município de Piraí adotou esse modelo para 100% de sua população, em 2002. Este estudo tem por objetivo analisar o cuidado oferecido no município, na perspectiva teórica da integralidade, utilizando como condição traçadora o diabetes mellitus, descrevendo o desenvolvimento do atendimento e analisando o processo de trabalho à luz dos protocolos e normas recomendadas, assim como o cuidado na perspectiva do usuário. Foram realizadas entrevistas com profissionais que atuam há pelo menos três anos na mesma unidade e com usuários cadastrados minimamente por um ano, excluindo-se aqueles com quadros mais graves. Foi utilizado instrumento padronizado e elaborado com intenção de promover relatos sobre acesso, acolhimento, vínculo-responsabilização, coordenação de cuidado, uso de protocolos, resolubilidade, autonomia e percepção de cuidado pelo paciente em três unidades da estratégia de Piraí. A partir da análise dos resultados, observamos que o acesso aos serviços de saúde qualifica a atenção, por meio do atendimento personalizado e acolhedor, percebido a partir de relatos sobre o agendamento de 1 consulta, consulta subsequente, atendimento de emergência, acesso via telefone e priorização da população que reside em locais mais distantes da unidade. Com relação ao vínculo, os usuários reconhecem as profissionais que trabalham nas unidades, o que aproxima a equipe dos usuários e contribui para o estabelecimento de relações de longa duração e efetividade da atenção. Percebe-se a responsabilidade com a vida do paciente e o foco do trabalho no indivíduo. Os usuários mantêm uma relação de confiança. Buscar autonomia destes através da promoção de trabalhos em grupos e visitas domiciliares é uma realidade, muito embora nos pareça que existe uma dificuldade de superar a transmissão de informações, pela troca de experiências, ou mesmo de entender a forma de pensar do paciente em relação a sua condição de saúde, buscando habilidades para lidar com a situação. Isso faz com que o desenvolvimento de uma organização rotineira de grupos seja algo em que a equipe encontra dificuldades. À luz dos protocolos, são constatadas a busca ativa e a realização adequada com relação ao número e aprazamento das consultas médicas. No entanto, o registro no prontuário foi um problema detectado. O cuidado ao paciente, a partir dos registros, é desenvolvido principalmente pelo profissional médico. A avaliação por parte de outras categorias profissionais de nível superior é pouco expressa. Do ponto de vista biológico, as metas estabelecidas em protocolo para os usuários são atingidas por um número restrito de usuários. Essas situações demonstram a necessidade de investimentos que favoreçam a superação desses desafios.

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[ES]Hoy en día la simulación de elementos de red y de redes completas supone una herramienta esencial para las telecomunicaciones, pudiendo ayudar en el dimensionado y el análisis de las mismas, así como en el estudio de problemáticas y escenarios que puedan darse. Uno de estos puntos de gran interés para el estudio es ARQ, y más concretamente, las técnicas de Stop & Wait y Go Back N. Así pues, nace dentro del grupo de investigación NQAS la necesidad de elaborar un conjunto de simulaciones sobre estas técnicas, con especial interés sobre la recolección de datos relacionados con el rendimiento de las mismas. Se pretende diseñar y simular una serie de escenarios de red partiendo de módulos simples con funciones de envío, conmutación y recepción de paquetes, escalándolo gradualmente para aumentar las funcionalidades de los mismos, hasta conseguir el diseño e implementación de redes basadas en dicha arquitectura cuyos enlaces estén bajo la cobertura de instancias de protocolo ARQ (Stop & Wait, Go Back N). Se tratará el resultado de las simulaciones mediante la recolección de estadísticas relacionadas con rendimiento y desempeño de las técnicas.

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Este estudo tem como objeto o documento Reflexões aos Novos Gestores Municipais de Saúde e questiona qual abordagem de planejamento é utilizada nos documentos distribuídos aos novos gestores da saúde municipal, buscando uma aproximação a partir de seus objetivos. Apresenta e analisa o documento, que é distribuído às Secretarias de Saúde para gestores e planejadores da saúde nos municípios brasileiros, identificando o tipo de abordagem relativa ao planejamento em saúde. Esse documento, formulado pelo CONASEMS, que delibera sobre o planejamento da saúde municipal, é uma tentativa de clarear a missão dos novos gestores de prover o planejamento da saúde nos municípios brasileiros, e sua relevância é conhecer o posicionamento dos órgãos centrais sobre o modelo de planejamento. Para fundamentar teoricamente o estudo, foi escolhido o método CENDESOPAS, o planejamento estratégico de Mario Testa e o planejamento estratégico situacional de Carlus Matus. Metodologicamente, utiliza um estudo documental com abordagem qualitativa, e como procedimento metodológico, uma análise temática de conteúdo segundo Bardin, aplicada a alguns itens do documento com maior aderência aos objetivos. A partir das etapas sugeridas por Bardin, chega-se a três categorias de análise: aspectos políticos do planejamento; planejamento e programação; e modelos de atenção. Apresenta os achados destacando partes dos itens do documento, correlacionando-os com o referencial teórico do estudo. Os resultados das categorias evidenciam que nos aspectos políticos do planejamento existem traços da abordagem do CENDES-OPAS, mas as abordagens do planejamento estratégico e estratégico situacional ficam mais evidentes a partir dos termos demanda e diretrizes políticas, programa de governo, participação de atores no planejamento e pactuações, bastante utilizados por Carlus Matus e Mario Testa. Na categoria planejamento e programação, as abordagens relativas ao planejamento ficam mescladas, evidenciando as abordagens do planejamento estratégico com predominância para o planejamento estratégico situacional. Com relação à categoria modelo de atenção, o documento aponta para a necessidade do fortalecimento e organização da Atenção Básica/Primária com mudanças nas práticas de saúde, que devem ter como foco a integralidade. Finaliza entendendo que as abordagens que o documento utiliza têm maior correspondência com as do planejamento estratégico e planejamento estratégico situacional. O documento não busca instrumentalizar os gestores para o como fazer, mas procura evidenciar os aspectos subjetivos do planejamento como forma de despertar em cada gestor uma imagem-objetivo para a operacionalização das políticas, dos princípios e das diretrizes do SUS.