Matrix acidizing is used in carbonate formations to create wormholes that connect the formation to the wellbore. Hydrochloric acid, organic acids, or mixtures of these acids are typically used in matrix acidizing treatments of carbonate reservoirs. However, the use of these acids in deep wells has some major drawbacks including high and uncontrolled reaction rate and corrosion to well tubulars, especially those made of chrome-based tubulars (Cr-13 and duplex steel), and these problems become severe at high temperatures. Hydrochloric acid (HCl) and its based fluids have a major drawback in stimulating shallow (low fracture gradient) formations as they may cause face dissolution (formation surface washout) if injected at low rates. The objective of stimulation of sandstone reservoirs is to remove the damage caused to the production zone during drilling or completion operations. Many problems may occur during sandstone acidizing with Hydrochloric/Hydrofluoric acids (HCl/HF) mud acid. Among those problems: decomposition of clays in HCl acids, precipitation of fluosilicates, the presence of carbonate can cause the precipitation of calcium fluorides, silica-gel filming, colloidal silica-gel precipitation, and mixing between various stages of the treatment. To overcome problems associated with strong acids, chelating agents were introduced and used in the field. However, major concerns with most of these chemicals are their limited dissolving power and negative environmental impact. Glutamic acid diacetic acid (GLDA) a newly developed environmentally friendly chelate was examined as stand-alone stimulation fluid in deep oil and gas wells. In this study we used GLDA to stimulate carbonate cores (calcite and dolomite). GLDA was also used to stimulate and remove the damage from different sandstone cores containing different compositions of clay minerals. Carbonate cores (calcite and dolomite) of 6 and 20 in. length and 1.5 in. diameter were used in the coreflood experiments. Coreflood experiments were run at temperatures ranging from 180 to 300oF. Ethylene diamine tetra acetic acid (EDTA), hydroxyl ethylethylene diaminetriacetic acid (HEDTA), and GLDA were used to stimulate and remove the damage from different sandstone cores at high temperatures. X-ray Computed Topography (CT) scans were used to determine the effectiveness of these fluids in stimulation calcite and dolomite cores and removing the damage from sandstone cores. The sandstone cores used in this study contain from 1 to 18 wt percent illite (swellable and migratable clay mineral). GLDA was found to be highly effective in creating wormholes over a wide range of pH (1.7-13) in calcite cores. Increasing temperature enhanced the reaction rate, more calcite was dissolved, and larger wormholes were formed for different pH with smaller volumes of GLDA solutions. GLDA has a prolonged activity and leads to a decreased surface spending resulting in face dissolution and therefore acts deeper in the formation. In addition, GLDA was very effective in creating wormholes in the dolomite core as it is a good chelate for magnesium. Coreflood experiments showed that at high pH values (pH =11) GLDA, HEDTA, and EDTA were almost the same in increasing the permeability of both Berea and Bandera sandstone cores. GLDA, HEDTA, and EDTA were compatible with Bandera sandstone cores which contains 10 wt percent Illite. The weight loss from the core was highest in case of HEDTA and lowest in case of GLDA at pH 11. At low pH values (pH =4) 0.6M GLDA performed better than 0.6M HEDTA in the coreflood experiments. The permeability ratio (final/initial) for Bandera sandstone cores was 2 in the case of GLDA and 1.2 in the case of HEDTA at pH of 4 and 300oF. At high pH HEDTA was the best chelating agent to stimulate different sandstone cores, and at low pH GLDA was the best one. For Berea sandstone cores EDTA at high pH of 11 was the best in increasing the permeability of the core at 300oF. The low pH GLDA based fluid has been especially designed for high temperature oil well stimulation in carbonate and sandstone rock. Extensive studies have proved that GLDA effectively created wormholes in carbonate cores, is gentle to most types of casing including Cr-based tubular, has a high thermal stability and gives no unwanted interactions with carbonate or sandstone formations. These unique properties ensure that it can be safely used under extreme conditions for which the current technologies do not give optimal results. Furthermore, this stimulation fluid contributes to a sustainable future as it based on readily biodegradable GLDA that is made from natural and renewable raw material.

Matrix acidizing is a well stimulation technique used to remove formation damage in the near wellbore region. But it comes with an associated set of challenges such as corrosion of the tubulars and iron precipitation in the formation. To counter these challenges, different chemicals, or additives, are added to the acid solution such as corrosion inhibitors and iron control agents. These additives may change the relative permeability of the spent acid, and formation wettability, and may either hinder or improve spent acid clean-up. Such effects of additives on the spent acid clean-up have not been documented. The aim of this research effort was to document the aforementioned change in the spent acid concentration (by using one additive at a time) before and after gas flowback. This was achieved by acidizing cores and creating wormholes halfway through them, then CT scanning them to observe the spent acid region. Later on, gas was flown through the core opposite to the direction of acid injection for 2 hours, and another CT scan was taken. The difference between the two CT scans was documented. Using a different additive each time, a series of such CT scans was obtained to develop an idea about whether the said additive was beneficial or detrimental to spent acid clean-up. It was found that the corrosion inhibitor FA-CI performed the best in terms of spent acid recovery after gas flowback for both Indiana Limestone and Texas Cream Chalk cores. Moreover, the corrosion inhibitor MI-CI was the worst for Indiana Limestone and the non-emulsifying agent M-NEA the worst for Texas Cream Chalk for spent acid recovery after gas flowback.

The arithmetic operations in most digital system are in the conventional binary number systems. However, the finite field arithmetic has also been widely used in applications of cryptography and communication channel coding. For example, finite field constant multiplication is applied to the advanced encryption standard (AES) and in the Reel-Solomon code. In this thesis, we develop a synthesizer that can automatically generate optimized gate-level netlists for constant matrix multiplication in Galois Field GF(2^n). The logic minimization is based on the a new common-factor elimination (CSE) algorithm that can efficiently finds the shared common factors among all the bit-level Boolean equations. Both the area and speed performance are considered during the logic optimization process. Experimental results show that the synthesized circuits have better area and/or speed performance compared with those obtained using Synopsys logic synthesis tools.

In this paper we adopt a new technique combined with operator theorem to analysis linear time-varying system. This make us solve the robust control problems of linear time-varying system more easily. Also, we can apply this method to the problems of linear time-invarying system. First, we construct the operator we want to use, then apply it to the linear time-varying system. Moreover, we can apply this method to the structure singular value problem of robust control, and the result is similar with the linear time-invarying system. Then , we construct the standard control problem , and adopt linear matrix in- equality to get suboptimal controller to satisfy the robust performance we need. Finally,we use numerical method to discuss it.

ABSTRACT In terms of theory, the matrix organization is not only beneficial to preserve and develop the core technologies of enterprise, is but also equipped with flexible functions. This is an ideal research and development organization. Though there are many relevant studies in this respect previously with project or balanced matrix organization as research target, yet many companies adopt the functional matrix organization. Besides the research alliance is formed among enterprises in jointly developing new product/new technique which operational model will be the same as management model of functional matrix organization. As a result this initiates the research motive. This research adopts the exploratory research of case analysis including the compilation and study of relevant literatures as well as case interview, analysis and comparison, finally concludes ¡§The Key Successful Factors of Research & Development Management in the Functional Matrix Organization¡¨. The following conclusions are obtained by this research: An enterprise implements the project research and development of functional matrix organization and must be equipped with the following conditions: 1. The high ranking supervisors support and manifest toward project: the supervisor should clearly manifest the project importance, authorize and support the project leader as well as request the coordination of functional departments. 2. Sufficient Resource: It includes the required professional personnel, technology, budget and time to complete the project, meanwhile the flexibility for counteraction has to be prepared. 3. Appropriate Project Leader: The leader has to be equipped with professional capability, trust from supervisor, especially communication ability and leadership to acquire the coordination of functional chief and project members. 4. Attractive and Definite Object: The project object has to satisfy the sense of achievement of project members, inspire their motives, while the definite object can avoid the unnecessary problems in the results valuation. This article also submits the following suggestions on project execution method: 1. To adopt management by object: When the management by object is adopted. the functional chief supervises his subordinates to complete the preset project and project leader is focused on completed quality, schedule and required budget of object in the project execution period. As such the conflict occurrence can be reduced. Besides project leader doesn¡¦t have to spend too much time on internal management; however the leader can generate more close interactivity with customers that is surely beneficial to achieve the object and performance. 2. Effective Project Information System: The effective project information system can provide the written data to realize the project progress, assure project quality, increase the project realization of project members as well as compile and provide the effective historical data. 3. To Build up Project Team: If project members can work together under project object and develop a project team culture with more awareness and less conflict, this surely facilitates the smooth implementation of project. As a result the project leader does not have to be formally authorized his commanding power from organization, still he is able to inspire its members to proactively work hard in attaining the object. 4. The project leader has the rights of evaluation and allocation: The project leader should be more aware of contributions from his members than other chiefs. If project leader has the performance reward allocation that will facilitate the members be fully dedicated to project implementation. In the project management of matrix organization, the functional department is responsible for sub-project work as well as responsibility of project performance. Therefore project leader should have the performance evaluation toward overall functional department.

The switched-beam antenna is one type of the smart antennas, which consists of the antenna array and the beamforming network. The four-beam smart antenna generates four beams to cover a 120¢X area, which can be used to improve the carrier-to-interference ratio and the frequency reuse of a cellular system. Due to the attractive features of microstrip antennas such as low profile, easy fabrication, and low cost, we use microstrip antennas as array elements. In this thesis, we propose a novel four-beam beamforming network which consists of a 4¡Ñ4 Butler Matrix and four 180¢X power dividers. This network is able to provide low side-lobe level. A modified Butler Matrix not only simplifies the circuit of the 8¡Ñ8 Butler Matrix, but also meet the requirement of the original Butler Matrix. From the result of measurement, the side-lobe level of each beam of the modified Butler Matrix is less than ¡V10 dB. We also show that this method is applicable to any Butler matrix.

Zeolites ZSM-5 (SiO2/Al2O3=30~280) and Y(SiO2/Al2O3=5.2~80) are bound with silica gel (Ludox HS-40 and Ludox AS-40) and alumina (γ- Al2O3 and boehmite) by different binding methods, namely, gel-mixing, powder-mixing and powder-wet-mixing methods. The acidities of the bound catalysts and the zeolite powder are determined by NH3-TPD and FTIR. The textures of these catalysts are analyzed on a BET machine with nitrogen as a probe molecule. The micropore surface area and micropore volume are determined by t-plot method. Micropore volume distribution is determined by Horvath-Kawazoe approach with a cylindrical pore model. Mesopore volume distribution is determined by BJH method from the nitrogen desorption isotherm. Silica from the binder may react with extra-framework alumina in zeolites to form a new protonic acid. SiO2-bound catalysts have less strong acidity, Bronsted acidity and Lewis acidity than the zeolite powder. Also, the strength of strong acid sites of the zeolites is reduced when silica is embedded. Micropore surface area and micropore volume are reduced by about 19% and 18%, respectively, indicating some micropores of ZSM-5 are blocked on binding with silica. SiO2-bound ZSM-5 catalysts have less catalytic activity for butane transformation (cracking and disproportionation) and ethylene oligomerization than ZSM-5 powder. When alumina is used as a binder, both the total acid sites and Lewis acid sites are increased. Micropore surface area and micropore volume of ZSM-5 powder are reduced by 26% and 23%, respectively, indicating some micropores of ZSM-5 are blocked by the alumina binder. Alumina-bound catalysts showed a lower activity for butane transformation and ethylene oligomerization than ZSM-5 powder. Alkaline metals content in the binder is a crucial factor that influences the acidity of a bound catalyst. The metal cations neutralize more selectively Bronsted acid sites than Lewis acid sites. Alkaline metal cations in the binder and micropore blockage cause the bound catalysts to have a lower catalytic activity than the zeolite powder.

Welding of metal matrix composites (MMCs) is an alternative to their mechanical joining, since they are difficult to machine. Published literature in fusion welding of similar composites shows metallurgical problems. This study investigates the weldability of A359/SiC/10p aluminum SiC MMC. Statistical experiments were performed to identify the significant variables and their effects on the hardness, tensile and bending strengths, ductility, and microstructure of the weld. Finite Element Analysis (FEA) was used to predict the preheat temperature field across the weld and the weld pool temperature. Welding current, welding speed, and the preheat temperature (300-350??C) affected the weld quality significantly. It was seen that the fracture of the welded specimens was either in the base MMC or in the weld indicating a stronger interface between the weld and the base MMC. Oxides formation was controlled along the weld joint. Low heat inputs provided higher weld strengths and better weld integrity. It was found that the weld strengths were approximately 85% of the parent material strength. The weld region had higher extent of uniform mixing of base and filler metal when welded at low currents and high welding speeds. These adequate thermal conditions helped the SiC particles to stay in the central weld region. The interface reaction between the matrix and SiC particles was hindered due to controlled heat inputs and formation of harmful Al4C3 flakes was suppressed. The hardness values were found to be slightly higher in the base metal rich region. There was no significant loss in the hardness of the heat affected zone. The ductility of the weld was considerably increased to 6.0-7.0% due to the addition of Al-Si filler metal.

Well stimulation techniques are applied on a regular basis to enhance productivity and maximize recovery in oil and gas wells. Among these techniques, matrix acidizing is probably the most widely performed job because of its relative low cost, compared to hydraulic fracturing, and suitability to both generate extra production capacity and to restore original productivity in damaged wells. The acidizing process leads to increased economic reserves, improving the ultimate recovery in both sandstone and carbonate reservoirs. Matrix acidizing consists of injecting an acid solution into the formation, at a pressure below the fracture pressure to dissolve some of the minerals present in the rock with the primary objective of removing damage near the wellbore, hence restoring the natural permeability and greatly improving well productivity. Reservoir heterogeneity plays a significant role in the success of acidizing treatments because of its influence on damage removal mechanisms, and is strongly related to dissolution pattern of the matrix. The standard acid treatments are HCl mixtures to dissolve carbonate minerals and HCl- HF formulations to attack those plugging minerals, mainly silicates (clays and feldspars). A matrix acidizing apparatus for conducting linear core flooding was built and the operational procedure for safe, easy, and comprehensive use of the equipment was detailed. It was capable of reproducing different conditions regarding flow rate, pressure, and temperature. Extensive preliminary experiments were carried out on core samples of both Berea sandstone and Cream Chalk carbonate to evaluate the effect of rock heterogeneities and treatment conditions on acidizing mechanisms. The results obtained from the experiments showed that the temperature activates the reaction rate of HF-HCl acid mixtures in sandstone acidizing. The use of higher concentrations of HF, particularly at high temperatures, may cause deconsolidation of the matrix adversely affecting the final stimulation results. It was also seen that the higher the flow rate the better the permeability response, until certain optimal flow rates are reached which appears to be 30 ml/min for Berea sandstone. Highly permeable and macroscopic channels were created when acidizing limestone cores with HCl 15%. In carbonate rocks, there is an optimum acid injection rate at which the dominant wormhole system is formed.

An adding-doubling method is employed to calculate the reflected Stokes parameters for cirrus cloud layers composed of different habits and effective sizes. The elements of the Mueller matrix are determined from the reflected Stokes parameters by considering four different incident polarization states. The sensitivity of these elements is observed by comparing different ice crystal habits, effective sizes, and optical depth. The Mueller elements are strongly dependent on habit. The three habits, aggregate, bullet rosette, and plate, are observed and the M12/M11,M43/M11 and M44/M11 elements are discussed. The wavelength used is 0.532µm, which is the lidar wavelength used on the CALIPSO satellite. The linear depolarization ratio is also discussed. The method of subtracting the two depolarization ratios, is noted as another way to possibly better distinguish ice crystal habits. The sensitivity of the Mueller matrix to effective size is also observed. For three size distributions, the Mueller elements indicate no strong dependence. This may be due to the assumption of randomly oriented ice. Also, using an absorbing wavelength might provide dependence. Finally, the Mueller elements are dependent on optical depth. For a greater optical depth, the strength of reflection increases while the polarization decreases. As the optical depth increases, any peak-like features become non-existent.