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The Significance of Deepwater Oil Drilling for the US Energy Security: The Case of the Gulf of Mexico

This study seeks to quantify and model the significance of the deepwater oil development for domestic US energy supplies in the short-term. It explores the significance and potential contribution deepwater oil supply from the Gulf of Mexico (GoM) can make in providing energy security to the US. The output of this research demonstrates the growth in deepwater oil production and how this latter relates to total US oil production over the next 10 years; and therefore the role it can play in providing energy security to the USA. The literature offers commercial and academic debate on this topic. The research model analyses current available data and make sensible assumptions on the likely future growth of deepwater oil production in the GoM based on a number of scenarios. Our results support the high/best case and suggest that deepwater oil from the GoM can significantly provide energy security to the US on the short term. However, on the long term and in order to maintain its energy security, the US needs to develop and use renewable sources of energy.

Electrical Properties of Novel Lead Zirconate/Synthetic Rubber Composite Materials

Problem statement: Perovskite lead zirconate exhibits in an orthorhombic formation at a temperature below the Curie temperature, T_C. Approach: The orthorhombic is non-centrosymmetric which is capable of spontaneous polarization (electronic, ionic and orientation), depending on their composition and volume fraction. Results: The results from FTIR spectroscopy, XRD patterns, and SEM indicate that the lead zirconate particles are dispersed in Acrylic Rubber (AR72) matrix. At a small amount of lead zirconate particulates present in the AR72 matrix, at nearly 0.3986% V/V (AR72/PZ_5), the electrical conductivity increases dramatically by two orders of magnitude. Conclusion/Recommendations: Our synthetic Rubber (AR72)/lead Zirconate (PbZrO₃) composite materials can be successfully used as the candidate materials of soft Electroactive (ER) actuators, sensors, artificial muscles, and smart engineering devices.

Effective Atomic Number of Lead Sodium Borate Glass Systems at 662 keV

Mass attenuation coefficients of glass systems xPbO: 20Na₂O: (80-x)B₂O₃ (x = 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 and 55% mol) were determined at 662 keV photon energy using gamma rays transmission method. The theoretical values of mass attenuation coefficients were calculated by WinXCom program. These coefficients were then used to determine the effective atomic numbers of glass samples. All shielding parameters were increased with increasing of PbO concentration. Our results have uncertainty less than 1% between experimental and theoretical values.

Proposed Reliability Techniques on Soil and Rock Excavations

Problem statement: Assessment of the ground mass excavation is normally done by the deterministic method. A quantitative indication of mass stability provides as an index term known �the Factor of Safety (F.S.)�. There are uncertain to some degrees, such as only a single value of mass properties is used or variation in geologic conditions, computed values of F.S. are never absolutely precise. An alternative measurement of stability regarding use of index terms �Reliability (R) and probability of failure [p (f)]� is to cope with the uncertainty well. Concurrent processes of stability assessment are done using both the deterministic and reliability methods. Field data on the reliability approach assumed to be either normal function or lognormal function distribution. Conclusion/Recommendations: Three types of reliability model are proposed. Modeling types are based on the safety margin, the most likely value of F.S. and data simulation, respectively. These probabilistic values obtained from each model, are compared with the deterministic method. The risk on ground mass failures and environmental impacts due to excavation, be better defined and also achieved the optimized cost of construction excavation.

Design of a Fuzzy Logic Sliding mode Model Following Controller for a Brushless DC Servomotor Drivers

Problem statement: A brushless DC servomotor position control system using a fuzzy logic sliding mode model following controller or FLSMFC is presented. Approach: The FLSMFC structure consists of an integrator and variable structure system. Results: The integrator ensures the elimination of steady state error due to step and ramp command inputs, while the fuzzy control would maintain the insensitivity to parameter variation and disturbances. The FLSMFC strategy is implemented and applied to a position control of a brushless DC servomotor. Conclusion/Recommendations: Experimental results indicated that FLSMFC system performance with respect to the sensitivity to parameter variations is greatly reduced. Also, its can achieve a rather accurate servo tracking and avoids the chattering phenomenon.

Effect of Fuel Properties on Exhaust Emissions during Warm-Up Process

Problem statement: Increasing air pollutions the big problem form internal combustion engines. Several attempts have been done to get a cleaner combustion process, one of which is the use of fuel ethanol in gasoline engines. Approach: The addition of ethanol in fuel will be change fuel properties. Results: To know the effect of fuel properties on engine performance and emissions produced, in this study was conducted tests against some root material, which is 95 octane gasoline, ethanol/gasoline 10, 20% ethanol, ethanol 30%, when the warm-up process. Conclusion/Recommendations: Result from this research, addition of ethanol in the fuel produces emissions of HC and CO is higher at the start, but with increasing time engine running the addition of ethanol to reduce emissions.

Forecasting of Energy Consumption and Pollutant Emission for Road Transportation Policies Evaluation

Problem statement: The energy demand in Thailand has significantly increased over last ten years, particularly in transportation sector. Road transportation contributes the highest energy consumption, 38% of the total energy in the whole country, but it consumes 60% of the total energy usage in the northern region of Thailand. Various chemical pollutants emitted from the road transportation affecting to human health and global warming situations. Approach: This study applied the system dynamics model to forecast the energy consumption and pollutant emission from the road transportation and to evaluate the policies in transportation management. The model integrates five related systems: (1) the socio-economic, (2) demographic, (3) land use, (4) transportation and (5) energy consumption and pollutant emission of vehicle. Data from 2002-2009 was collected and used to forecast the system from 2010-2030. The proposed model was applied to evaluate and compare five transportation policy scenarios including road expansion, public transit incentive, land use restriction, alternative vehicle (eco-car) promoting and alternative fuel promoting. Results: The both energy consumption and pollutant emission in the study area will increase substantially if no management plans are implemented. The energy consumption will increase from 958.2 kTOE in 2010-1,144.8 and 1,369.2 kTOE in 2020 and 2030. The pollutant emission will increase from 2.983 million MTCOE in 2010-3.497 and 4.182 million MTCOE in 2020 and 2030. Among five proposed scenarios, the public transit incentive policy maximizes the goal of energy conservation. It can save 730.21 kTOE and reduce 2.23 million MTCOE per year. Conclusion/Recommendation: The system dynamics modeling approach appropriates to simulate the trend of energy consumption and pollutant emission from the transportation sector. This application could be used as the tool for planning and management the transportation in context of the energy conservation and sustainably.

A Hybrid of Fuzzy and Proportional-Integral-Derivative Controller for Electro-Hydraulic Position Servo System

Problem statement: While classical PID controllers are sensitive to variations in the system parameters, Fuzzy controllers do not need precise information about the system variables in order to be effective. However, PID controllers are better able to control and minimize the steady state error of the system. To enhance the controller performance, hybridization of these two controller structures comes to one mind immediately to exploit the beneficial sides of both categories. Approach: A hybrid fuzzy PID controller for the Electro-Hydraulic Position Servo System (EHPSS) was proposed in this study. The proposed control scheme was separated into two parts, fuzzy controller and PID controller. Fuzzy controller was used to control the piston when the piston locates far away from the target position. PID controller is applied when the piston is near the desired position. Results: We demonstrated the performance of control scheme via experiments performed on the EHPSS. Conclusion: The results from the experiments showed that the proposed hybrid fuzzy PID controller has superior performance compared to individual PID controller and fuzzy controller.

A Study of Solar Reflector Efficiency of Parabolic Dual Trough

Problem statement: The receiver of parabolic dual trough had been designed and built in order to increase efficiency of solar radiation accumulation by using iron-aluminum sheet as an intermediate in receiving heat and it is the study into how to benefit from solar radiation energy. This research proposed the principle of changing solar radiation to be heating energy by using aluminum sheet made into dual parabolic curve tilted with iron-aluminum sheet which was receiver of radiation reflection. Approach: This dual parabolic curve could be adjusted so that heat obtained from the solar radiation accumulation, which was the focus, could spread around iron-aluminum sheet. In testing of heating by solar energy, the unit would be tilted at 16� to the North-South in order to receive solar radiation and the unit was arranged horizontally. The test was classified into 4 conditions including (1) laying the unit horizontally and un-drive the motor, iron-aluminum sheet would be put in place unmoved in vertical line; (2) laying the unit horizontally and drive motor so that iron-aluminum sheet could be moved upwards and downwards along the vertical line; (3) laying the unit to be tilted at 16� with plane level and un-drive motor and (4) laying the unit to be tilted at 16� with the plane level and drive motor so that iron-aluminum sheet could be moved upwards and downwards along the vertical line. Results: It was found from the test of temperature of iron-aluminum sheet that on the first condition, the highest temperature of iron sheet was 75.2�C and the highest temperature of aluminum was 84.7 �C; on the second condition, the highest temperature of iron sheet was 90.6�C and the highest temperature of aluminum was 97.2�C; on the third condition, the highest temperature of iron sheet was 87.4�C and the highest temperature of aluminum was 93.4�C; on the fourth condition, the highest temperature of iron sheet was 94.5�C and the highest temperature of aluminum was 89.4�C. Therefore, the test of laying the unit to be tilted at 16� with the plane level and driving motor leaded to the high temperature since the perpendicular of light and the spreading of sunlight from dual parabolic curve could cover all area. Conclusion: These results indicate dual parabolic curve could be increased efficiency of solar radiation accumulation by using iron-aluminum sheet as an intermediate in receiving heat.

Arm Movement Recorder

Problem statement: Human arm movement is widely studied nowadays. Some movements of arm are performed frequently in everyday life. Devices that can record the path of movement are important in studying human arm gesture. Approach: This project was performed the five degree-of-freedom exoskeleton that was designed and constructed to observe position and orientation values of various movement in x-y-z coordinates of human arm. All joints of the exoskeleton were attached with potentiometers for tracking a human arm trajectory. A dedicated computer with a software application, LabVIEW, obtained the data from arm movement and translated to the end effector coordinate. A calibration method for the exoskeleton was proposed for a particular path, a circle. A value correction for the chosen path was introduced in this calibration process and error of root mean square was used as performance index to measure radial error and geometric error of the exoskeleton. Results: Experiments with a human arm for executing repetitive tasks were performed to study. There were two sets of experiments. With correction factor applied to both experiments, the average Error of Root Mean Square (ERMS) reduced drastically. Conclusion: With the correction factor, this device could use to record particaular movement of human�s arm with small error.