The focus of this thesis is formulation and development of a mathematical framework for the solution of the contingency constrained optimal power flow (OPF) based on sequential quadratic programming. The contingency constrained optimal power flow minimizes the total cost of a base case operating state as well as the expected cost of recovery from contingencies such as line or generation outages. The sequential quadratic programming (SCP) OPF formulation has been expanded in order to recognize contingency conditions and the problem is solved as a single entity by an efficient interior point method. The new formulation takes into account the system corrective capabilities in response to contingencies introduced through ramp-rate constraints. Contingency constrained OPF is a very challenging problem, because each contingency considered introduces a new problem as large as the base case problem. By proper system reduction and benefits of constraint relaxation (active set) methods, in which transmission constraints are not introduced until they are violated, the size of the system can be reduced significantly Therefore, restricting our attention to the active set constraint set makes this large problem significantly smaller and computationally feasible.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Vita. / Includes bibliographical references. / by Pierre Dersin. / Ph.D.

The trucking industry is vitally important to the economy, providing an essential service by transporting goods between businesses and consumers. The less-than-truckload (LTL) industry is an important segment, serving businesses that ship quantities between 150 lbs and 10,000 lbs. Large LTL carriers use thousands of drivers to move loads between terminals in their network, and each driver may be used for multiple dispatches between rest periods. Driver wages are a major component of transportation costs. Consequently, cost-effective driver management is of crucial importance for the profitability of LTL carriers. This thesis investigates a variety of issues related to driver management. In this thesis, we describe a dynamic driver scheduling scheme developed for a large U.S. LTL carrier. Dynamic driver scheduling is challenging because drivers must abide by a complex set of rules, including government and union regulations, and trucking moves are not pre-scheduled. The technology developed combines greedy search with enumeration of time-feasible driver duties, and is capable of generating cost-effective schedules covering 15,000 20,000 loads in minutes. One of the key tactical questions faced by an LTL carrier is how many drivers to locate at each terminal. Unionized carriers have bid drivers that can only move loads between their domicile and a designated region. The developed allocation technology determines the number of drivers to allocate to each terminal as well as the designated region for bid drivers. Computational experiments based on real-life dispatch data demonstrate the effectiveness of our domiciling methodology, and show that union rules may result in substantially larger driver fleets, in some cases up to 50% larger. Finally, we investigate a fundamental question related to driver management in order to obtain some fundamental insights: determining the minimum number of drivers required to cover a set of loaded moves. The problem is shown to be polynomially solvable without any restrictions on driver schedules. For variants with restrictions, several easily computable lower bounds are derived, integer programming formulations are presented, and fast heuristics are designed and analyzed. A computational study provides insights into the quality of the lower bounds and heuristic solutions.

近年來我國公部門為能創造小而全的政府，積極從事組織再造與行政革新。除原業務需執行外，又增加新業務，為能彌補暫時性工作高峰的人力不足，而使用人力資源彈性政策、大量私法契約人員與派遣人員等臨時人力，以期增加人事運用彈性與降低人事經費支出。我國政府為因應暫時性工作高峰所帶來的人力需求，在運用臨時勞力上已有一段時間，但因現階段法令、政策與相關規範未能符合公部門使用臨時勞動力之需求與人事運用之彈性，以致造成人數眾多之臨時勞動人力之勞動權益未能獲得妥適之對待之情形。 本研究係從人力資源彈性策略理論及公部門契約性人力運用產生與發展之影響談起，探究我國食品公衛機關之私法契約人力及派遣人力運用與管理之情形，再輔以深度訪談之個案分析，藉由實務的觀察與訪談，並以人力資源彈性策略（職能彈性、契約彈性、薪資彈性、績效管理）及相關管理措施（進用、遴選、角色、任務、定位、考核、權利與義務、相關勞動基準法規等）來作歸納分析並獲致結論，最後期能作為該機關未來有效之管理與應用。 本論文結論與建議:在管理面：一、因應突發事件，正式預算編制員額不足，有續採私法契約人力及派遣人力支應之所需；可請增補充人力。二、人力之管理分工不一，盡可能尋找單一窗口。三、目前對臨時人員職位或身分做過多的分類，建議尋找法規鬆綁於薪資、福利、訓練與出國之限制上盡量一致。四、在管理與激勵上，能理解員工個性，盡量平等與民主管理並激發其內在潛力、主動性和創造精神。五、仍要有不適任淘汰機制及避免久任的情況。在法治面：一、建議重新檢討如何打破臨時人員不能行使公權力的困難。二、減少或整合或重新檢討私法契約臨時人員及派遣人力之運用。三、陞遷與遷調制度與權益福利及生涯規劃保障，可向政府建議在未來檢討人事制度時可考量給予鬆綁或容許契約人力到達一定年資變成正式人員。在其他方面：精進職掌業務管理制度或風險管理，減少臨時重大突發事件。 / According to the original services cannot be abandoned as well as the new services were added and temporary manpower shortage during peak work that the Taiwan government is actively engaging in organizational reengineering and administrative reform as well as creating the small but complete government in recent years. The public sectors used the adopt manpower flexibility strategy such as using the contractual staffs and employing the dispatched laborers to increase personnel flexibility and reduce personnel salary. But bounding by the law, the government agencies cannot meet the needs of temporary labor and flexibility in using the personnel. Furthermore, it makes a large number of temporary labor’s right failed to get reasonable treatment. This study used the qualitative method on flexibility strategy of human resource and contractual manpower in Taiwan's agencies. The in-depth interview and observation was conducted to collect data, including flexibility strategy of human resource (functional flexibility, contract flexibility, wage flexibility and performance management) and management measurement(hiring, selection, roles, tasks, orientation, assessment, rights and obligations and the Labor Standards Law). Based on these data to summarize and make conclusion. The result could be as a reference for managing of government agencies. The results and suggestions as the following: First, the management phase: 1. It is necessary to continue to use the contractual staffs and dispatched laborers for temporary manpower shortage during the peak work.2. Management of the contractual manpower is responsible for the different units that could to find a single window. 3. The regulations of making payroll, benefits, training and limiting for aboard could be consensus to the normal staffs. 4. Their inherent potential, initiative and creativity should be stimulated through the management and motivation. 5. The evaluation of labor unfitting should be established and avoid the long time hiring. Secondly, for the legal phase: 1. It should be reviewed the issue of the temporary staff in public sector cannot conduct the government jobs.2. The interests of contractual workers should be protected. 3. Should review the promotion and career planning system to allow contractual labor to promote to formal staffs when getting the enough working experience. In other phase, the temporary incidents could reduce through the responsibilities planning and risk management.

Two studies are presented quantifying the impact of plug-in hybrid vehicles (PHEVs) on power systems. The first study quantifies this impact in terms of (a) primary fuel utilization shifts, (b) pollution shifts, and (c) total cost for consumers. The second study quantifies this impact on distribution transformers. In the first study vehicle and power system simulations are used to compute the expected power system fuels utilized to meet a projected level of power demand. The projected electric power demand includes business as usual electric load and random PHEV charging electric load. In the second study the impact on distribution transformers is quantified through a loss of life calculation. The loss of life calculation is based on distribution transformer hot-spot temperature. The hot-spot temperature is estimated using an electro-thermal distribution transformer model and is a function of the transformer currents. The transformer currents are computed using a center-tapped single phase transformer model. Random business as usual and PHEV charging electric loading is assumed.

Thesis (MTech(Electrical Engineering))--Cape Peninsula University of Technology, 2011 / In a situation, where there is a shortage of power generation or the power stations are operating with a very low reserve margin, as is typically the current position in South Africa, there is a need to operate distribution network at the highest possible efficiency by utilising network power loss reduction techniques. Such techniques are especially important when contingencies occur as they tend to increase loss, reduce efficiencies and cause power supplies to such networks to increase. This increase can cause the network or multiples of such networks to be load shed as the power stations do not have the reserve margins to meet this increased demand. The ideal situation would thus be to minimise network loss and in so doing decrease the amount of power needed and possibly avoid load shedding. Thus, there is a need to study efficiency, network loss reduction under contingency conditions and this is the focus of the research. Most large urban distribution networks are operated as ring main networks. Ring networks are considered to have less power loss. However, a major component in a ring network can cause the loss to substantially increase; resulting in power shortage in the network. There is an urgency to eliminate high network loss. An efficiency plan was developed for a large ring network that reduces the loss so that its input power can be decreased. In this way, the available power existing due to the contingency can be more evenly spread, and the number of ring main networks to be load shed could be reduced.

Industries such as trade, manufacturing and transportation have undergone significant changes due to the globalization concept. Sea ports play a very important role in building and strengthening the economies of countries worldwide. Due to the high rate of production, the work load has increased at the ports which resulted into financial as well as capacity problems. As a result of such problems, cost optimized and automated solutions are being developed and introduced at the ports. In the horizontal transport system of the sea ports, AGVs are one of those automated solutions used to transport containers from ships to yard and vice versa. Newer and more practices are being employed to make the efficient transportation of these AGVs. Numexia has recently introduced a new version of Cassette AGVs called Zero-Emission C-AGV. A conceptual model is developed for Zero-Emission C-AGVs and different layouts are evaluated using multi agent-based simulation. The greedy algorithm has been used for the efficient dispatching of jobs. The Simulation will carry out the dispatching of jobs for C-AGVs between quay area and yard using different layouts and scenarios for the unloading operation.

D.Ing. / This thesis initially reviews current empirical and probabilistic electrical load models available to distribution design engineers today to calculate voltage regulation levels in low voltage residential, commercial and light industrial consumer networks. Although both empirical and probabilistic techniques have extensively been used for residential consumers in recent years, it has been concluded that commercial and light industrial consumer loads have not been a focus area of probabilistic load study for purposes of low voltage feeder design. However, traditional empirical techniques, which include adjustments for diversity to accommodate non-coincidental electrical loading conditions, have generally been found to be applied using in-house design directives with only a few international publications attempting to address the problem. This work defines the light industrial group of consumers in accordance with its international Standard Industrial Classification (SIC) and presents case studies on a small group of three different types of light industrial sub-classes, It is proposed and proved that the electrical load models can satisfactorily be described as beta-distributed load current models at the instant of group or individual maximum power demand on typical characteristic 24-hour load cycles. Characteristic mean load profiles were obtained by recording repetitive daily loading of different sub-classes, ensuring adequate sample size at all times. Probabilistic modelling of light industrial loads using beta-distributed load current at maximum demand is a new innovation in the modelling of light industrial loads. This work is further -complemented by the development of a new probabilistic summation algorithm in spreadsheet format. This algorithm adds any selected number of characteristic load current profiles, adjusted for scale, power factor, and load current imbalance, and identifies the combined instant of group or system maximum demand. This spreadsheet also calculates the characteristic beta pdf parameters per phase describing the spread and profile of the combined system loading at maximum demand. These parameters are then conveniently used as input values to existing probabilistic voltage regulation algorithms to calculate voltage regulation in single-, bi- and three-phase low voltage distribution networks.

Remote hybrid power systems (RHPS) serve local off-grid loads or various island grids when no grid extension is possible. They combine renewable resources, conventional generators and energy storage systems in order to balance the load at any moment, while ensuring power quality and energy security similar to large centralized grids. Modelling such a complex system is crucial for carrying out proper simulations for predicting the system’s behavior and for optimal sizing of components. The model should include an estimation of the renewable resource availability over the period of the simulation, a prediction of the load consumption and time variation, the choice of technologies, a prior dimensioning approach, an energy dispatching strategy between the components and, finally, the behavioral model of all components. This study limits its scope to the simulation of a RHPS composed of solar PV panels, a diesel generator set, and a Li-ion battery bank supplying a dynamic isolated load with a daily demand variation between 10 kW and 80 kW. Methods for building load scenarii are explained first and then, rules of thumbs for selecting the technologies and pre-sizing the components are reviewed. Commonly used dispatching strategies are described before detailing the algorithm of a Matlab behavioral model for the system’s components with an emphasis on the proper prediction of performance and aging for the Li-ion battery model. Finally, a 10-year simulation is carried out over a case study and the results are analyzed.

Reinforcement learning techniques offer a very powerful method of finding solutions in unpredictable problem environments where human supervision is not possible. However, in many real world situations, the state space needed to represent the solutions becomes so large that using these methods becomes infeasible. Often the vast majority of these states are not valuable in finding the optimal solution. This work introduces a novel method of using linear programming to identify and represent the small area of the state space that is most likely to lead to a near-optimal solution, significantly reducing the memory requirements and time needed to arrive at a solution. An empirical study is provided to show the validity of this method with respect to a specific problem in vehicle dispatching. This study demonstrates that, in problems that are too large for a traditional reinforcement learning agent, this new approach yields solutions that are a significant improvement over other nonlearning methods. In addition, this new method is shown to be robust to changing conditions both during training and execution. Finally, some areas of future work are outlined to introduce how this new approach might be applied to additional problems and environments.