The ballistic impact of Twaron CT709® plain weave fabrics is studied using an explicit finite element method. Many existing approximations pertaining to woven fabrics cannot adequately represent strain rate-dependent behavior exhibited by the Twaron fabrics. One-dimensional models based on linear viscoelasticity can account for rate dependency but are limited by the simplifying assumptions on the fabric architecture and stress state. In the current study, a three-dimensional fabric model is developed by treating each individual yarn as a continuum. The yarn behavior is phenomenologically described using a three-dimensional linear viscoelastic constitutive relation. A user subroutine VUMAT for ABAQUS/Explicit® is developed to incorporate the constitutive behavior. By using the newly developed viscoelasticity model, a parametric study is carried out to analyze the effects of various parameters on the impact behavior of the Twaron fabrics, which include projectile shape and mass, gripping conditions, inter-yarn friction, and the number of fabric layers. The study leads to the determination of the optimal number of fabric layers and the optimized level of inter-yarn friction that are needed to achieve the maximum energy absorption at specified impact speeds. The present study successfully utilizes the combination of 3D weave architecture and the strain rate dependent material behavior. Majority of the existing work is based either on geometry simplification or assumption of elastic material behavior. Another significant advantage with the present approach is that the mechanical constitutive relation, coded in FORTRAN®, is universal in application. The desired material behavior can be obtained by just varying the material constants in the code. This allows for the extension of this work to any fabric material which exhibits a strain-rate dependent behavior in addition to Twaron®. The results pertaining to optimal number of fabric layers and inter-yarn friction levels can aid in the manufacturing of fabric with regard to the desired level of lubrication/additives to improve the fabric performance under impact.

Flow kinematics of green water due to plunging breaking waves interacting with a simplified, three-dimensional model structure was investigated in laboratory. Two breaking wave conditions were tested: one with waves impinging and breaking on the vertical wall of the model at the still water level and the other with waves impinging and breaking on the horizontal deck surface. The incoming wave parameters were selected similar to observed wave parameters for the maximum wave height for Hurricane Ivan based on Froude scaling. The Bubble Image Velocimetry (BIV) technique was used to measure the flow velocity. Measurements were taken on a vertical plane located at the center of the deck surface and a horizontal plane located slightly above the deck surface. The evolution of green water flow kinematics in time and space is revealed in the study. The unsteady and non-uniform velocities were found to be quite different between the two wave conditions, even though the incoming waves are nearly identical. It was observed that the maximum velocity appears near the green water wave front and is 1.44C with C being the wave phase speed for the deck impingement case and 1.24C for wall impingement case. The velocity variations in the present study were compared with that in an earlier study using a two-dimensional model with the same wave condition as in the wall impingement condition. It was found that the magnitudes of the maximum vertical velocity is very different between these two models (1.7C in the 3D model versus 2.9C in the 2D model), whereas the magnitudes of the maximum horizontal velocity on the deck are very similar (1.2C in both 3D and 2D models). The applicability of dam-break theory on green water velocity prediction for the three-dimensional model was also investigated. It was found that the dam-break theory works very well in terms of predicting the maximum velocity, which is also the front velocity, but not the spatial distribution of the velocity on the deck. Furthermore, pressure measurements were performed at two vertical planes: one at the centre and the other at 0.05 m away from the centre. Ensemble averaged pressure variations were compared. Two types of pressure variations, impulsive type and non-impulsive type were observed. Impact pressure was successfully related to the pressure rising time. Void fraction was measured for few locations near the model front edge. Predictions of maximum impact pressure based on the measured pressure and flow velocity were investigated linking pressure with kinetic energy. Constant impact coefficient of 1.3 was found for wall impingement wave. However, for deck impingement wave, it was not possible to find a constant impact coefficient. It was also found that there is a linear relationship between the rising pressure gradient and the impact coefficient.

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In this thesis, the response of solder balls under high-speed impact was investigated. Five solder compositions, such as Sn/4.0Ag/0.5Cu,Sn/3.5Ag/0.75Cu,Sn/1.0Ag/1.0Cu, Sn/3.0Ag/0.5Cu and Sn/2.6Ag/0.6Cu with two pad surface finishes and ball impact test system were used to implement four kinds of experiments including different impact speeds, different hammers, different reflow times and different aging time in room temperature after reflow. From experiments, the variations of solder strength and mechanical properties were received and discussed. At the same time, failure modes and variations of solder structure after reflow were observed by using SEM and X-ray EDS. The experimental results show that maximum impact force on solder joints increases with the increasing of impact speed when it reaches a critical value. The impact force of Sn/2.6Ag/0.6Cu with Ni/Au pad finish is the maximum among all the solder compositions at varied impact speeds. Maximum impact force on solder joints will decrease with the increasing of mass of hammer. The strength of solder ball were reduced significantly after reflow, however, it makes no difference for solder strength to reflow twice. It was found that maximum impact force and impact energy of solder joints didn¡¦t change a lot, but the ductility and stiffness of them varied unstably under the condition of room temperature for seven days after reflow.

The purpose of thesis is to study the transient analysis of structural responses of solder joints under high-Speed impact. By using the experimental and simulation analysis. The experimental work can be divided into six parts, such as different impact speeds, different solder¡¦s components, different pad finishing, different UBM and Runner, and different thickness of PBO. From experiments, the variations of solder joint strength and mechanical properties were received and discussed and the failure mode. The empirical results show that maximum impact force on solder joints decreases as the impact speed increasing. The solder joint strength becomes stronger with the solder adopting elements of Ni and Co. The strength of solder ball was reduced significantly after a reflow. The intermetallic compound strength reduces with solder ball adopting high content of Ag. In impact test, the resistance of UBM of TiAl is better than that of TiAlTi. The runner adopted with the element Pd can improve the IMC reliablility to reduce Mode I failure. However, the PBO thickness has little influence on IMC strength. From the numerical results, in the consideration of strain rate on solder joint the mechanical properties of solder joint could be effectively investigated. According to the different IMC strength there will produce three failure modes of solder ball and the impact force becomes higher as the IMC strength setting higher. If the lower yield stress is considered in lower IMC strength, the impact force is not the highest of all, but the time duration is the highest of all.

Chichin District of Kaohsiung City not only embraces the harbor coastal space of natural water coast resources, but also owns rich human historic sites, delicious seafood cuisine, etc. To most of the local residents or tourists, the district all along has tremendous tourist charm. In order to attract more tourists to visit this district and meet the residents¡¦ eager requests for recreation, in recent years Kaohsiung municipal government has been positively developing diversified tourist facilities and items in this district in expectation for promotion of people¡¦s satisfaction on the overall tourist recreational experience. Therefore, a deep understanding of the residents¡¦ or tourists¡¦ satisfaction, extent of recognition and background difference towards the tourism development of the district is an important subject when taking options in the keenly competitive tourist environment in future. And this investigation can also provide a reference for the relevant departments to plan for their future direction and to review their work for improvement. This research mainly investigates from three aspects: ¡§community conscious-ness,¡¨ ¡§recognition towards the impact of tourism development¡¨ and ¡§participation attitude and environmental residential experience,¡¨ etc. of the Chichin residents of Kaohsiung. In studying the Kaohsiung municipal government¡¦s urging for tourism development of Chichin District, the research meanwhile gives an understanding on the residents¡¦ concentration of community consciousness, their attitude towards the development of tourism and their residential experience, etc. The results of the research can also provide more appropriate strategies for the Kaohsiung municipal government in positioning the future tourism development of Chichin District of Kaohsiung City by using the effective resources. The results of the research show that over the ¡§analysis on residents¡¦ participation attitude and environmental residential experience,¡¨ the residents currently residing in this district mostly gave such reasons for their residence as ¡§residing here generation after generation,¡¨ ¡§friends and relatives mostly living in this district¡¨ and ¡§relationship of work,¡¨ etc. The ratio of these factors is 75.2% of the tested samples. In this way, the researcher can interpret the situation that among these residents, being different from those of other districts, there established tight kinship and friendship. And they are helpful to the concentration of community consciousness. At the same time we can learn from the results of the research that there is an obvious correlation between ¡§sex,¡¨ ¡§residing alley¡¨ in the attributes of the residents¡¦ basic background, and ¡§high or low group of social consciousness,¡¨ and ¡§high or low group of recognition of tourism development impact¡¨ respectively. After analysis on the results of this research, it is suggested that the actions that the relevant administrative departments should take are: 1.¡§Reserve of resources,¡¨ including the confirmation for establishment of a system for tourism attraction in Chichin District of Kaohsiung City, a unification of the things and rights of management so as to avoid excessive development, etc. 2. ¡§Community development,¡¨ an effective use of the properties of the generally high community consciousness among the residents of Chichin, and a maintenance of high extent of concentration through the assistance by the third department. Finally, this research also mentions that if the angle is changed by taking the experience and recognition of residents as a reference for planning the development of the district, then perhaps the optimal effects can be acquired from development.

From the viewpoint of land economics, any change in land use manner will require new public facilities added to the area under development and bear external impact on the area. The merit of the fundamental principle to remove, through levying rezoning on land use, the external effects brought on by alterations in development should be recognized. However, because the levy of rezoning on land utilization involves people¡¦s rights and obligations, the proper execution of this system has a considerable impact on people¡¦s privilege. The current rezoning system on land utilization implemented in Taiwan has been in practice for many years; it is also widely criticized. Concerns over such subjects as ambiguous definition and nature of rezoning, lack of legal status for the levy of rezoning, lack of standard for the calculation of rezoning amounts are usually raised. Therefore, the government must work to try to establish a complete, reasonable rezoning system on land utilization. The author conducted the research by examining the system of impact fees and linkage fees implemented in the United States, the planning obligations system implemented in Britain, and the development charge system implemented in Singapore and examining their experience, and reviewing the relevant laws and concerns with regard to the current rezoning on land utilization in Taiwan. Moreover, after analyzing and describing the policy trend of the government¡¦s effort to establish the land development obligations system, the author tried to understand, through case study, questionnaire inquiry and interview methods, the opinion of scholars and experts, land and estate developers, government offices, and local residents, and then based on this understanding, tried to formulate a framework that would be appropriate for the rezoning system on land utilization in Taiwan. The study maintains that in implementing the rezoning system on land utilization, the most important principle is to respect the market function and endow the levy of rezoning with legal status. Then in conformity with this principle, complete and reasonable measures concerning the rezoning system on land utilization are to be constructed. This study suggests that, in a short period of time, the statute that governs the levy of rezoning, to name one ¡V Urban Planning law, be revised so that the rezoning system can gain legal ground and be implemented legally. At the same time, the negotiating mechanism for development permit should be strengthened so that the external cost influenced by development can be effectively included as the content for negotiation. For the long term, the central authority in charge should integrate the separate regulations on rezoning that belong to various offices in charge so as to establish a reasonable rezoning system on land utilization that conforms to the market function and to give this system a legal status. This status should be the basis for the implementation of this system. The applicant for alterations in land utilization should be the subject for the levy, and the levy should be executed in the form of cash donation, land donation and construction of public facilities. The government administration should be considered. For the levy amounts, calculation equations can be established as part of this system, and the concerned local government and the owner should negotiate to figure out the upper and lower limits of the estimated amount. The time to levy should be decided separately from the levy method, but they should match. With regard to the use, management and maintenance of rezoning items, the concerned local government should, according to the characteristics of rezoning items, establish accounts and authorities for special funds. These special funds should be only appropriated for improving, constructing, and managing the public facilities that have been influenced by alterations in land utilization. This perfect rezoning system on land utilization should enable the government, developer, and local residents to share land resources and harvest the plentiful fruit of perennial development.

The austenite stainless in high energy welding and tradition welding (TIG) produce different texture revolution and mechanicl property are main research. From EBSD analysis,austenite stainless in EBW,make more random texture to TIG welding,and main texture in TIG welding are cubic texture {100}<001> and copper texture {110}<1-1 2>.From EBW,there are some different texture in up fusion zone and down fusion zone .Experience of impact and hardness ,which find out copper and brass texture have more mechanical property for low-temperature, £_ ferrite content in center welding fusion and boundary fusion zone have different percent, then that can explain how differnt hardness value in center and fusion boundary about mechanical property.

In this study, particle impact damping is measured for a cantilever beam with a particle-filled enclosure attached to its free end. Many particle materials are tested: lead spheres, steel spheres, glass spheres, tungsten carbide pellets, lead dust, steel dust, and sand. The effects of particle size are also investigated. Particle diameters are varied from about 0.2 mm to 3 mm. The experimental data collected is offered as a resourceful database for future development of an analytical model of particle impact damping.

A two-mass model with a spring and a damper in the vertical direction, accounting for vertical translational motion and a torsional spring and a damper connecting the rotational motion of two masses is used to simulate the dynamics of a tennis ball as it comes into contact with a flat surface. The model is supposed to behave as a rigid body in the horizontal direction. The model is used to predict contact of the ball with the ground and applies from start of contact to end of contact. The springs and dampers for both the vertical and the rotational direction are linear. Differential equations of motion for the two-mass system are formulated in a plane. Two scenarios of contact are considered: Slip and no-slip. In the slip case, Coulomb??s law relates the tangential contact force acting on the outer mass with the normal contact force, whereas in the no-slip case, a kinematic constraint relates the horizontal coordinate of the center of mass of the system with the rotational coordinate of the outer mass. Incorporating these constraints in the differential equations of motion and applying initial conditions, the equations are solved for kinematics and kinetics of these two different scenarios by application of the methods for the solutions of second-order linear differential equations. Experimental data for incidence and rebound kinematics of the tennis ball with incidence zero spin, topspin and backspin is available. The incidence angles in the data range from 17 degrees up to 70 degrees. Simulations using the developed equations are performed and for some specific ratios of inner and outer mass and mass moments of inertia, along with the spring-damper coefficients, theoretical predictions for the kinematics of rebound agree well with the experimental data. In many cases of incidence, the simulations predict transition from sliding to rolling during the contact, which is in accordance with the results obtained from available experimental measurements conducted on tennis balls. Thus the two-mass model provides a satisfactory approximation of the tennis ball dynamics during contact.