Unit commitment is one of the most important subjects with respect to the economical operation of power systems, which attempts to minimize the total thermal generating cost while satisfying all the necessary restrictive conditions. ¡@¡@This thesis proposes a short-term thermal generating unit commitment by genetic algorithm and back propagation network. Genetic algorithm is based on the optimization theory developed from natural evolution principles, and in the optimization process, seeks a set of solutions simultaneously rather than any single one by adopting stochastic movement rule from one solution to another, which prevents restriction to fractional minimal values. Neural networks method outperforms in speed and stability. This thesis uses back propagation network method to complete neural networks and sets the optimal unit combination derived from genetic algorithm as the target output. ¡@¡@Under fixed electrical systems, instant responsiveness can be calculated by neural networks. When the systematical architecture changes, genetic algorithm can be applied to re-evaluation of the optimal unit commitment, hoping to improve the pitfalls of traditional methods. ¡@¡@This thesis takes the power system of six units for example to conduct performance assessment. The results show that genetic algorithm provides solutions closer to the overall optimal solution than traditional methods in optimizing unit commitment. On the other hand, neural networks method can not only approximate the solution obtained by genetic algorithm but also process faster than any other methods.

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ABSTRACT Due to the continuous variation of medical policies, the competition of healthcare services markets are even more drastic and face more challenges. Among them, the advantage in competition for each hospital and clinic is information service, as a result, the superintendent of information unit in hospitals must obtain not only knowledge about information specialty but also general disposition of healthcare system; the superintendent of routine interactions between authorized superior officials and the subordinates with academic technique, under the huge pressure of heavy responsibility with minor power, how can women leaders overcome obstacles and which kinds of career development philosophy they adopt to distinguish themselves and achieve success; in the other hand, they choose to be a housewife. This study mainly explores the reasons for their choice of either working or not working. The purpose of this study is revealing the insight of the pressures and the strategies of career development as a female supervisor in healthcare information unit. Research topics focus on the roleplay under the tradictional social expection, the pressures from both family and workplace, and the strategies of career planning. I employ the depth interview as the data collection method. The research results are summarized in three parts, they are: (1). In the concept of tradictional value: the tradictional value affects the attitude of the gender roleplay; the stablilty becomes the most critcal critera of career evaluation; the traditional gender roleplay affects the development of strategy of career development; (2). The adjustment between family and workplace pressur: the conflict is derived from the tradictional value; the lower the conflict the higher the accomplishment they achieve; (3). Strategies of career development: looking for the support from family; create the opportunity of competion advantage; self-promotion; receiving advice from friends and advisors. Keywords: Healthcare Information Unit, Female Information Supervisor

The aim of this study is to understand students¡¦ solutions (to problems related to time, time interval, and time unit conversion) and to analyze their common errors and possible causes. Students¡¦ problem-solving strategies and error types were also categorized and used as a reference for improvement in teaching and a scaffold for supporting students' learning. Findings in this research were three: 1. Distinction between time and interval. Students were performing better in the concept of interval than in the concept of time. They also performed well in total time consumed and in daily life problems such as clock time. However, problems with longer text description would make it harder for students to do problem solving in the concept of time and interval. 2. Problem-solving types. The problem-solving types ranked by the frequency are: (1) processing larger units first; (2) converting time from high scale to low scale and vice-versa; (3) using fractions; (4) using decimals; and (5) using addition. 3. Error types: The error types presented by students in solving time-related problems include: (1) interference of the decimal; (2) interference between non-decimal time conversion systems; (3) insufficient knowledge about division; (4) unclear concept about high and low scales of time; (5) incorrect calculation; (6) influence of the clock dial structure; (7) incorrect problem-solving strategy; (8) misjudgment of keywords; and (9) ignorance of problem conditions.

In this thesis, the Hybrid Genetic Algorithm-Ant Colony Optimization (GACO) approach is presented to solve the unit commitment problem (UC), and comparison with the results obtained using literature methods. Then this thesis applied the ability of the Genetic Algorithm (GA) operated after Ant Colony Optimization (ACO) can promote the ACO efficiency. The objective of GA is to improve the searching quality of ants by optimizing themselves to generate a better result, because the ants produced randomly by pheromone process are not necessary better. This method can not only enhance the neighborhood search, but can also search the optimum solution quickly to advance convergence. The other objective of this thesis is to investigate an influence of emission constraints on generation scheduling. The motivation for this objective comes from the efforts to reduce negative trends in a climate change. In this market structure, the independent power producers have to deal with several complex issues arising from uncertainties in spot market prices, and technical constraints which need to be considered while scheduling generation and trading for the next day. In addition to finding dispatch and unit commitment decisions while maximizing its profit, their scheduling models should include trading decisions like spot-market buy and sell. The model proposed in this thesis build on the combined carbon finance and spot market formulation, and help generators in deciding on when these commitments could be beneficial.

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Thesis (M.S. in International Affairs)--Sam Nunn School of International Affairs, Georgia Institute of Technology, 2003. Directed by Roderick Duncan. / Includes bibliographical references (leaves 178-188).

Accurately determining one’s location has long been a persistent problem in navigation and has reappeared in recent years in the field of mobile computing. The ability to determine a device’s location indoors is needed for both automation and efficient communication in collaborative robotic and sensor networks. Technologies such as indoor GPS transmitters and Cricket have been employed, but have had limited success due to cost, accuracy, and power consumption. The Inertial Solution for Accurately Assessing location Coordinates (ISAAC) was developed as a means of filling this need without requiring infrastructure or expensive components to accurately determine position, inside or outside. ISAAC is based on modified six-degrees-of-freedom (6DOF) dead reckoning algorithms currently being used by Unmanned Aerial Vehicles (UAV). UAVs typically have access to other types of sensors to supplement and/or replace the IMU measurements. ISAAC was implemented using a low-cost MEMS 6DOF IMU in which the onboard firmware was modified to incorporate the dead reckoning calculations and communications necessary to realize ISAAC. ISAAC was implemented as a portable unit which communicated with a host computer through an RS-232 interface. ISAAC did not perform as well as expected; the location coordinates were very inconsistent with device movements and did not produce any useful data. The correct intermediate results of the calculations and subsequent review by a local subject-matter-expert implies that the source of the erroneous results lie with the accuracy and precision of the MEMS IMU. ISAAC presents a foundation for future work where more robust sensors and/or filtering can be used for further examination of inertial-based location systems. / text

Inertial measurement units (IMUs) are used in a wide range of applications to estimate position, velocity, and attitude of vehicles. The high cost of tactical grade IMUs makes the low-cost microelectromechanical systems (MEMS) based IMUs appealing. These types of IMUs are less accurate, so to counteract this effect, multiple and different configurations should be used. The work presented here provides efficient and low cost solutions using different configurations of redundant (multiple) MEMS-IMU swarms, which increase the level of accuracy to potentially the order of that of a tactical IMU. Several configurations are presented and compared through different methods. / text