Rooting and exploring are two behaviours pigs in the wild spend considerable time doing. When kept in pens with limited access to bedding materials stress can originate and often lead to undesired behaviours. The purpose of this study was to investigate whether environmental enrichment in terms of ropes and an activity ball containing piglet food, can provide an outlet for their natural behaviours and thus reduce undesired behaviours. In total, 141 pigs were used and divided into three groups, control-, activity ball- and rope groups. The observation methods used were 1/0 recording and instantaneous recording with 15 second intervals. In the rope group a significant difference was seen in the interaction with enrichment, as it was higher on day 1. Between the three groups, a decrease in ear-, tail- and equipment biting was seen in the two enriched groups on day 1. On day 3 these difference could only be seen between the control group and the other two groups in equipment biting. However, few data ware collected and so we cannot confirm our hypotheses, concerning whether the environmental enrichments decreased the undesirable behaviours or not. However, most of our findings are in compliance with earlier studies as we among other things found that the rope worked better than the activity ball and that the interest of the enrichments decreased with time.

The capability of hand-eye coordination is one of the dexterous skills owned by human beings. In order to reproduce the skillfully operational technique and demonstrate basic hand-eye coordination technique, a robotic wrist system with stereo visual feedback strategy from the viewpoint of table tennis is presented in this thesis. Based on the concept of aerodynamics and collision mechanics, the exerted forces acting on the ball are analyzed. Three stages, including the ball flying in the air, inelastic collision between a racket and the ball, and hitting strategy of humans, will be investigated. At the same time, three-dimensional information for the scene is established using images acquired by dual cameras with a calibration process. Therefore, the flying status of the ball and its position in the space can be calculated. The robotic wrist located underneath will then be controlled to hit the ball to allow it bouncing upwards. The mechanical wrist is operated by three servo motors to simulate actual movement of human wrist. The objective is to successively hit the ball with the racket to achieve intelligent hand-eye coordination control on ball bouncing.

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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 thesis is mainly focused on the investigation of optimal process operation, which is appropriate for new-type stacking package product to achieve the assembly products of two or more packages. By melting solder balls to form the stacking package products, the eventual goals of lightness, thinness and smallness will be accomplished. To increase and stabilize the production yield of stacking package products, different flux, different temperature setting with reflow oven, and different flux dipping method were used. With Taguchi design of experiment, the solder balls combined situations under varied conditions were observed. The best process character of new-type integration assembly products was achieved. The experimental results and mass production data prove that different flux type and temperature setting with reflow oven won¡¦t influence the solder balls connection between two package products. Only the flux dipping method will directly affect solder balls connection between two package products. The abnormal phenomenon is the so-called cold joint in assembly plants. With innovation, silicon gel head is used as a flux adhesive way to achieve the goal of flux transferred. This method can be used in integration process of new-type stacking package products. That will certainly assure that every solder ball on each package product can be helpful for adhesion of flux. The experiments proved that the yield rate of solder balls connection of two package products is 100% after the stacking package products through reflow oven. This proves that using flux with silicon gel head on new-type stacking package products is the best way of process operation. The innovation of this new process has been granted a patent by the Patent office, ROC. Although this is a simple invention, it will bring profit to ASE Co. as well and ensure the leadership of new-type stacking package products in related industries. Keywords: Stack¡BSolder Ball¡BCold Joint¡BSilicon Pad

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.

The technology of multi-axis machining has been applied extensively to the manufacturing of dies, molds, and various aerospace components. For machining mechanical parts with complex, sculptured surfaces, the use of multi-axis machine tools is probably the only one solution for avoiding tool-part collision during machining. Since cutting force will be changed by cutter attitudes, the machined surface characteristic can also be affected by cutter attitudes. In this thesis, the major concern is focused on investigating the effect of the cutter attitude on machined surface roughness. Based on the relationship between the cutter incline angle and the enveloped condition in cutting, the correlation of the mean chip thickness and the cutter incline angle is observed. To identify the relationship between the cutter attitude and the workpiece surface roughness, experimental verification is performed by milling aluminum alloy material. By fixing the cutting depths and the width of tool paths, different spindle rotational speeds and cutter incline angles are taken to machine the workpieces. And then, the machined surfaces are measured for their surface roughness. Form the experimental results, it shows that the surface roughness will reach a peak value at a special cutter incline angle. The tendency between the surface roughness and the incline angle agrees with that between the mean chip thickness and the cutter attitude approximately.

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.

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