Short-Term Resource Allocation and Management

Almost all sectors of the economy, such as, government, healthcare, education, ship repair, construction, and manufacturing require project management. A key component of project management deals with scheduling of tasks such that limited resources are utilized in an effective manner. Current research on resource constrained project-scheduling has been classified as: a) Single project with single mode for various tasks, b) Single project with multiple task modes, c) Multiple projects with single task mode, and d) Multiple projects with multiple task modes.;This work extends the current multi-project, multi-mode scheduling techniques. The resources can be renewable, and non-renewable. In addition, it focuses on short term scheduling, that is, scheduling on an hourly, daily, or weekly basis. Long term scheduling assumes a stable system, that is, resources, priorities, and other constraints do no change during the scheduling period. In this research, short term scheduling assumes a dynamic system, that is, resources, priorities, and other constraints change over time.;A hybrid approach is proposed to address the dynamic nature of the problem. It is based on discrete event simulation and a set of empirical rules provided by the project manager. The project manager is assumed to be highly knowledgeable about the project. He/she is regarded as an integral part of the system. Such an approach is better suited to deal with real world scheduling. The proposed approach does not seek to provide a single optimum solution, instead, it generates a series of feasible solutions, along with the impact of each solution on schedule and cost.;Two project case studies dealing with finding an optimum solution were selected from the literature. The proposed technique was applied to the data set in these studies. In both cases the proposed approach found the optimum solution. The model was then applied to two additional problems to test the features that could not be tested on the dataset from the literature.;As for practical implications, the proposed approach enhances the decision making process, by providing more resource allocation flexibility, and results in improved solutions in terms of total project duration and cost. From an academic viewpoint, this research enriches the existing literature, as it provides an extension of the resource constrained project scheduling problems, a discrete event simulation and four cases studies which highlights relevant issues to model properly the complexity of real-life projects

Optimal task scheduling in a flexible manufacturing system using model checking

This paper demonstrates the use of model checking to solve the problem of optimal task scheduling in a flexible manufacturing system. The system is modelled as a discrete event system, for which the least restrictive safe behaviour is synthesised according to supervisory control theory. Then timing constraints are added to the model in the form of extended finitestate machines, and time-optimal schedules are computed using the discrete event systems and model checking tool Supremica. In the case study considered in this paper, which previously was only solved heuristically, the method successfully produces optimal schedules to manufacture up to 30 products of two different types. The method is furthermore used to find an optimal cycle, solving the scheduling problem of the case study for an arbitrary number of products in optimal or asymptotically close to optimal time

32 in \u2744: A management and environmental study of submarine construction at Portsmouth Navy Yard during World War II

After averaging the completion of less than two submarines a year in the 1930s, the Portsmouth Navy Yard completed an astonishing thirty-two submarines in 1944. The yard\u27s outstanding performance during World War II was the product of a highly motivated work force and a management team that thrived in a decentralized wartime shipyard environment. Employing aggressive and innovative management techniques that included employee empowerment, small teams, and mass production techniques to the extent that they could be applied to submarine construction at the time, the shipyard delivered submarines at unprecedented rates. There were downsides to the shipyard\u27s crowning achievements during the war that included landfills contaminated with toxic industrial waste, increased pollution of the Piscataqua River, and lost wetlands. In addition, the greatly increased employment and military presence at the yard brought challenges to local communities that struggled to increase housing, infrastructure, and services to accommodate the increased numbers of new residents. Not the least of these struggles included efforts to curb prostitution and an alarming increase in venereal disease. While wrestling with these day-to-day problems during the war, local communities feared an uncertain, and possibly economically disastrous, postwar future should peace bring dramatically reduced employment or closure of the yard. This dissertation looks at both sides of Portsmouth Navy Yard\u27s war years: the tremendous upside wherein remarkable submarine production records were achieved that brought economic prosperity to the area, and the downside that saw significant environmental abuse and sociological turmoil as communities adjusted to the problems that accompanied a Navy boomtown. A preliminary review places the yard in context with important national and international events between the wars to set the stage for an analysis of how the shipyard achieved 32 in \u2744, and the consequences of that success

Organizational Change Theory and the Factors for Sustaining Change: A Case Study of Three Public Sector Organizations Winners of the Virginia Award for Continuing Excellence

The purpose of this study is to investigate the factors associated with organizational change and with sustaining change in public sector organizations recognized for their change efforts as recipients of the Virginia Award for Continuing Excellence. This was a case study of three public sector organizations, located in and around urban settings in the state of Virginia. They include Air Combat Command located in Hampton; Hanover County Public Schools located outside Richmond; and Norfolk Naval Shipyard located in Portsmouth. Each of these organizations is notable as winners of the Virginia Senate Productivity and Quality Award for both the Medallion and Award for Continuing Excellence. The theoretical propositions are based on the Big Three Model of Change. These propositions include kinds of environmental movements (internal, external, and political), forms of change (identity, coordination, and control), and action roles (strategist, implementor, and recipient). Data collection on each case study came from archival files, documentation in the form of books, articles, brochures, and video presentations about the organizations, and interviews with key informants employed by the organization during and after the award period of time. The triangulation of data on these case studies suggested several factors that are associated with organizational change across all three public sector organizations. The factors include the political dimension, along with coordination of teams, plans, and training. A third factor is control which is a form of change that results in policy changes and is impacted by the influence of action roles. The fourth factor associated with organizational change, that was evident in each case, is the implementor action role. Within the three major dimensions of the Big Three Model of Change were other theoretical propositions that were supported by one or two data sources across all case studies. These other propositions did not provide the strength of the triangulation of evidence. However, each theoretical proposition was supported by one or two data sources and is worthy of note in identifying factors associated with organizational change. These other factors are the external and internal environment, strategists, and recipients. The test of sustained change was based on the theoretical propositions and five Award for Continuing Excellence criteria. Evidence to support the change factors of coordination and control was found in the archival files that referred to the continuous improvement and performance measurement award criteria. The archival files also included examples to support the theoretical propositions of strategist, implementor, and recipient and the related award criteria that referred to: top management commitment, employee development, and customer and supplier involvement. Archival references to the award criteria, the maturity of effort and results over time, in these organizations are further evidence of successful change, while interviews and documents offer strength to the evidence in the archival files. The research supports the Big Three Model of Change as a theoretical model that contains factors associated with change and sustained change in public sector organizations recognized for their past organizational change efforts

Future Greener Seaports:A Review of New Infrastructure, Challenges, and Energy Efficiency Measures

Recently, the application of renewable energy sources (RESs) for power distribution systems is growing immensely. This advancement brings several advantages, such as energy sustainability and reliability, easier maintenance, cost-effective energy sources, and ecofriendly. The application of RESs in maritime systems such as port microgrids massively improves energy efficiency and reduces the utilization of fossil fuels, which is a serious threat to the environment. Accordingly, ports are receiving several initiatives to improve their energy efficiency by deploying different types of RESs based on the power electronic converters. This paper conducts a systematic review to provide cutting-edge state-of-the-art on the modern electrification and infrastructure of seaports taking into account some challenges such as the environmental aspects, energy efficiency enhancement, renewable energy integration, and legislative and regulatory requirements. Moreover, the technological methods, including electrifications, digitalization, onshore power supply applications, and energy storage systems of ports, are addressed. Furthermore, details of some operational strategies such as energy-aware operations and peak-shaving are delivered. Besides, the infrastructure scheme to enhance the energy efficiency of modern ports, including port microgrids and seaport smart microgrids are delivered. Finally, the applications of nascent technologies in seaports are presented

Escalonamento ótimo baseado na teoria de controle supervisório aplicado a um estaleiro de reparo naval

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-graduação em Engenharia de Automação e Sistemas, Florianópolis, 2010A Teoria de Controle Supervisório (TCS) permite a síntese automática de supervisores não bloqueantes que habilitem todas e apenas as sequências que satisfaçam especificações de segurança para um sistema a eventos discretos temporizado. O supervisor ótimo que satisfaz as especificações de recursos, roteiros e prazos para problema do tipo jobshop contém todas as soluções de escalonamento possíveis. No entanto, o crescimento do número de estados dos modelos pode inviabilizar a solução para problemas reais. Nessa pesquisa, uma nova proposta de modelagem dos autômatos temporizados é desenvolvida com o objetivo de reduzir o tamanho dos modelos. Propõe-se também um algoritmo eficiente para síntese de escalonamento baseada na composição incremental dos roteiros de produção e prazos das tarefas e um método de bissecção para minimização do tempo de produção global e também dos tempos de produção de cada tarefa. Este método é aplicado a um estaleiro de reparo naval para o escalonamento das atividades nos cinco recursos principais para execução de dez obras distintas. Também foi desenvolvido um sistema que integra o planejamento da produção com uma ferramenta de síntese automática de supervisores para que o usuário não precise estar familiarizado com a TCS.The Supervisory Control Theory (SCT) allows automatic synthesis of nonblocking supervisors that ensures safety specifications to a timed discrete event system. The optimal supervisory that ensures the resources specifications, production routers, and due dates to the problem of jobshops provides all the possible solutions of scheduling. However, the size of the state space of the models can make impracticable the solution of such a problem. In this dissertation, a new modeling approach is proposed for the timed automata models in order to expressively reduce the size of the models. Also, it is proposed an efficient algorithm for the optimal schedules based on an incremental synthesis of the production routers and due dates. A method of bisection was developed to minimize of total production time and the lead times of jobs as well. This method is applied to a repair shipyard to schedule its activities in the five main resources and ten orders. From the research was developed a system that integrates the production planning with a tool of automatic synthesis of supervisors in order to make the interface an easier place for those users who are not used to SCT

Sustainable engineering challenges towards Industry 4.0: A comprehensive review

This article reviews Industry 4.0, its emerging phase, implementation, challenges, benefits, etc. It combines various fields where it has any influence and leaves some changes and where it requires some adaptation. Papers from the last 4 years are taken and analyzed, what is written about this topic in various countries with different backgrounds and economic development. Industry 4.0 affects the production environment by introducing new technologies which require a better-educated workforce so it affects education and requires some changes in curricula and ways of teaching. It brings new challenges and asks for a new approach from management to be able to handle fast and big changes in the business environment and to implement such innovation in production effectively