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The increasing world demand for oil has pushed oil companies to extract it from the ocean at extreme depths. With the increase in depth comes an increase in operation costs, especially the deep-sea equipment changeover cost. To be able to push the oil to the ocean surface, Electrical Submersible Pumps (ESPs) are commonly used as artificial lift. The changeover cost of these pumps in deep-water has been estimated to sometimes be as much as forty times the cost of a new pump. One common reason for the failure of ESPs is the erosion and abrasion created by the fine sands that seep through the gravel pack mesh in the well hole. These fine sand particles are most destructive to the bearings and bushings due to their capability to enter the clearances lubricated by the pumped fluid. Over time, the sustained abrasion and erosion in the different components of the ESP will affect the performance of the pump and could lead to its damage. This work describes the design, construction and evaluation of an erosion test rig built at the facilities of the Turbomachinery Laboratory in Texas A&M University. The test rig is capable of introducing 100 mesh (6 mil) sand into the flow loop, measure its concentration and separate it at the exit with minimal water loss. The pump under study is a Baker Hughes 10.25" WJE1000. The performance of the pump is described by measuring the head, flow rate, power and efficiency. The pump is equipped with accelerometers to detect the casing vibration as well as proximity probes in five locations along the pump to detect the internal vibrations of the shaft near the bearings as well as impeller radial movement. The baseline data, to be used for comparison with the worn out pump, has been shown and recommendations for the study method and operation of the rig are given.

Abstract Following the governor¡¦s policy to develop the competition and efficiency of the market¡Aevery industry goes into the liberalization and privatization all over the world¡Ait means to relieve the control and supervise of the market¡CThe power market of Taiwan also needs to follow the trend¡CExcept the relief of control and supervise¡Athe most important thing is to keep the balance of supply and demand¡Aas soon as relieving the whole power market¡Athat makes the customers of the power can have more choice¡C In order to keep the power supply stable¡Agovernor should establish a control and supervise department for increasing the competition and stability of the market¡CWe should open the information and use the theories of economic for attracting investors¡CWe need establish the frame of the power market of Taiwan due to the practice and experience of the relief of control and supervise in the developed countries¡CThe liberalization and privatization of the power industry is a gradual process and is done at the most suitable environment and time¡CSo we need to do the investigate of the factors which influence the liberalization and privatization of the power industry¡C When we relieve the control and supervise of the power market in Taiwan in the future¡Awe will face to many problems¡Asuch as the work right of the employee of Taipower¡Bstock offering¡Bthe stranded cost of Taipower¡Bthe long term contract of power purchase between Taipower and co-generators or independent power producers¡]I.P.P¡^¡Bthe power price of the secluded island and areas and the political mission which Taipower has been in charge till now¡Afor example¡Atake care of the development of industries¡Bfavored power price¡Bthe policy of energy¡C The excessive competition will loses the attraction of the investor and invalidate the market mechanism¡Afinally¡Athere will be a serious power shortage¡Awhich as the California of American¡CIf the control and supervise department of government is not good enough¡Ait will make the power supply short or excessive¡CThe power dispatching is also an important business¡Aif any trouble in the power dispatching ¡Athere will be a terrible blackout¡Afor example¡Athe terrible blackout on the northeast area of American and the Ontario province of Canada on 14 august¡A2003¡C The first strategy of the Taipower¡¦s liberalization and privatization is to reconstruct the organization¡Aovercome the inertia of organization and start a new mechanism¡CThe power generation department should raise the efficiency by change the old one to a new one¡Areduce the probability of breakdown¡Aincrease the availability¡FThe power transmission department should focus on the safety and quality of power transmission and management of block up¡Fthe power distribution and supply department should reinforce the customer service to get rid of the loss of customer¡C Keywords¡GIPP¡GIndependent Power Producer¡C ISO¡GIndependent System Operator¡C ESP¡GElectric Service Provider¡C PPP¡GPool Purchase Pricing¡C

In der vorliegenden Arbeit wurden die wichstigen Methoden untersucht, die bei der Realisierung von Algorithmen der asymmetrischen Kryptographie (Verteilung der –offentlichen Schlüssel, Generierung und Prüfung der elektronischen Unterschrift) verwendelt werden. Im Mittelpunkt stand die Durführung von berechnungen in den algebraischen Endstrukturen. Folgende Grundalgorithmen der asymmetrischen Kryptographie wurden in der Programiersprache C++ realisiert: die Addition (Substraktion) der Grossen Zahlen, die Potenzierung einer Grossen Zahl mit einer anderen Grossen Zahl. Eine analzse von Algorithmen der assimetrischen Kryptographie wurde durchgeführt, Schlussfolgerungen über die Effektivität der Algorithmen bei Anwendung in der Funktionen zur Berechnung und Prüfung der elektronischen digitalen Unterschrift gezogen.

Master’s thesis deals with anti-lock braking system and systems for riding stabilization of vehicles. Theoretical part of this paper describes active forces on a vehicle with emphasis on the braking process. The next part describes a design of a braking system with anti-lock braking system, and anti-slip regulation, and design of electronic stabilization program. Every subchapter dealing with system also contains a description of its function. Practical part of this thesis deals with measurement of braking with active and no active ABS done with Volkswagen Golf IV. This measurement was done on chassis dynamometer. Measured results describe the process of braking force and braking acceleration or deceleration. In the end of the thesis is comparison of results of braking with ABS for different pressure inside of tires.

Keepaway is a simpler subtask of robot soccer where three `keepers' attempt to keep possession of the ball while a `taker' tries to steal it from them. This is a less complex task than full robot soccer, and lends itself well as a testbed for multi-agent systems. This thesis does a comprehensive evaluation of various learning methods using neuroevolution with Enforced Sub-Populations (ESP) with the robocup soccer simulator. Both single and multi-component ESP are evaluated using various learning methods on homogeneous and heterogeneous teams of agents. In particular, the effectiveness of modularity and task decomposition for evolving keepaway teams is evaluated. It is shown that in the robocup soccer simulator, homogeneous agents controlled by monolithic networks perform the best. More complex learning approaches like layered learning, concurrent layered learning and co-evolution decrease the performance as does making the agents heterogeneous. The results are also compared with previous results in the keepaway domain. / text

English for Specific Purposes (ESP) has grown to become one of the most prominent areas of language learning and teaching today. There have been a number of studies that have investigated the effective ESP programs requiring relevant materials, knowledgeable instructors, and teamwork with subject matter professionals but it is not easy to find out studies related to effective ESP programs in the military. To explore and analyze English Advanced Class in Military Language Institute, it expects meaningful findings to indicate whether ESP theory for trainees is appropriately and effectively well embodied in English Advanced Class. To understand trainees’ needs, factors to affect trainees and trainees’ expectation toward English Advanced Class, the quantitative analysis of the questionnaire is conducted through descriptive statistics, Pearson correlation, and ANOVA in order to indicate the direction and relationship within variables. By analyzing data, the findings reveal that course materials and teaching style need to be considered to meet trainees’ needs before starting English Advanced Class. Also, this research identifies performances concerning about motivation, positive attitude and anxiety.

The MVP is a special type of Electrical Submersible Pumps (ESPs) manufactured by Baker Hughes, model no. G470, and is capable of handling multiphase flow up to 70% Gas Volume Fraction (GVF). Flows at high GVF cause conventional ESPs to surge. However, the special design of the impeller blades of the MVP ESP enables it to handle higher GVF. Dynamic behavior of the multiphase flow is studied experimentally and theoretically for this pump for the first time. In this work, a Computational Fluid Dynamics (CFD) simulation of an entire pump and detailed experimental analysis are performed. Meshing and CFD simulations are performed using the commercially available software ANSYS Fluent. An experimental facility has been designed and constructed to test the pump at different operating conditions. The pump is modeled and tested at two speeds; 3300 and 3600 rpm, using air-water mixtures with GVFs of 0, 5, 10, 25, 32 and 35%. The flow loop is controlled to produce different suction pressures up to 300psi. Pump pressure head is used to validate the CFD model for both single and two phase flows. Single phase CFD model was validated at 100 psi inlet pressure, while two phase models were validated at 200 psi inlet pressure. CFD simulations can predict the behavior of the pump at different speeds, flow rates, GVFs, and inlet pressures. Different diffuser designs are studied and simulated to improve the multistage pump performance. Enhanced diffuser designs increased the pump pressure head to up to 3.2%.