This thesis is composed of two designs: a PT (process, temperature) detector for 2¡ÑVDD output buffer with slew rate compensation, and a slew rate self-adjusting 2¡ÑVDD output buffer with PVT compensation. In the first topic, a PT detector for 2¡ÑVDD output buffer with slew-rate compensa-tion is proposed. The driving current of 2¡ÑVDD output stages varies provided that the process and temperature conditions are different. For example, the driving current of 2¡ÑVDD output stage will be low at poor PVT corners. By contrast, the driving current will be high at good PVT corners. The process corner and temperature of NMOS and PMOS should be detected by threshold voltage variation thereof, respectively, such that the slew rate compensation is feasible. The proposed sensors will carry out the PT de-tection and compensate the driving current based on the detected corner, such that the slew rate variation of the output stage will be reduced. The second topic is a slew rate self-adjusting 2¡ÑVDD output buffer with PVT compensation. An NMOS and PMOS process detector is proposed to detect the process corners of NMOS and PMOS, respectively, while the voltage and temperature sensor is proposed to detect the voltage and temperature variations by body effect.

This study was conducted to determine threshold levels for Warner-Bratzler shear (WBS) force of the beef value cuts. USDA Choice and USDA Select M. biceps femoris, M. gluteus medius, M. infraspinatus, M. longissimus lumborum, M. rectus femoris, M. triceps brachii, and M. vastus lateralis steaks were evaluated for palatability characteristics and tenderness acceptability by a consumer panel (n = 205). Steaks also were evaluated by WBS analysis. The relationship between consumer tenderness-like ratings and WBS was investigated through regression analysis. Threshold WBS levels could not be determined due to the low correlation between consumer tenderness ratings and WBS. Within a muscle, percent tenderness acceptability was determined for each of the tenderness-like ratings. After analyzing the consumer ratings, tenderness acceptability, and WBS values, it was apparent that there may not be a single WBS threshold value suitable for all muscles. Research indicates that there may be muscle-specific WBS threshold levels; these values were not established from this research.

Brood pheromone of the honey bee, (Apis mellifera) has been shown to elicit a wide array of primer and releaser effects on non‐foragers and foragers leading to the regulation of nursing, pollen foraging, and behavioral development such that the behavior of the colony may be regulated by the amount and condition of the larvae. To date, all studies into the effects of brood pheromone have either used uncharacterized whole extracts or a single blend of brood pheromone characterized from a population of honey bees in France. The variation in the relative proportions of the ten fatty‐acid ester components that characterize brood pheromone and some effects of this variation on pollen foraging and sucrose response thresholds were therefore observed. The objectives met in this dissertation were to determine whether changes in brood pheromone component proportions (blend) or amount communicates larval nutritional status and reports the results of observations of nurses and foragers in response to blends of brood pheromone from deprived and‐non deprived larvae, to measure how changes in brood pheromone blend changed pollen foraging behavior and if such changes could account for the pollen foraging differences between Africanized and European bees, and finally to observe the effects of exposure time on brood pheromone blend and to observe whether non‐foragers made contact with the pheromone. Brood pheromone was found to vary by larval rearing environment, but did not elicit the expected behaviors that would support a cue of nutritional status. Brood pheromone also varied significantly by mitochondrial lineage/population source and responses to brood pheromone appeared to be coadapted to blend, suggesting that brood pheromone may be important in race recognition. Finally, brood pheromone varied significantly over time and was found to be removed from sources by bees, suggesting possible mechanisms for loss of effect. Combined the results of this research indicate that brood pheromone blend differences lead to profound changes in colony behavior related to pollen foraging and food provisioning, providing novel tools for colony manipulation and mechanisms for understanding brood rearing division of labor and chemical communication.

This paper applies a real option approach to analyze the optimal decisions of mergers, stock offers, and cash offers. We use the two-stage approach to investigate the optimal decisions of mergers and acquisitions. At the first stage, the merger company has to choose the target company to obtain the largest synergy, which comes from the increasing return to scale, improved performance, acquired R&D, and increased market power. At the second stage, the main work is to determine the takeover threshold (timing), exchange rate of stocks or bid premium under the three forms of mergers and acquisitions. We find that the increasing return to scale, improved performance, and increased market power will lower takeover threshold and speed up merger activity. Finally, the forms of mergers and acquisitions will affect the timing and the returns of the acquirer and acquiree. Cash offers will happen even later than mergers and stock offers. This thesis also constructs a model to study the multi-firms¡¦ merger strategies and derives the multi-firms¡¦ synergy value, timing and terms of merges. In addition, we study the effect of firms¡¦ competitive intensity, market power, fixed cost, and demand shocks on the decisions of merges. We find that the increased competitive intensity, increased market power, higher fixed cost, and lower demand shocks will enhance the motives of merges and accelerate merger activities.

In the first part of this article, we discuss the time and the probability for the barrier option to become effective, and then employ the risk neutral assumption to derive the pricing formula of the barrier option. Our pricing formula is a closed form solution, and we may calculate the price of the barrier option without considering the Binomial tree of the underlying asset. We also calculate the traditional option price by our pricing formula, and compare the result to the value that is calculated by Binomial pricing formula. Both of them give the same value about the tradition option, and thus we may regard the tradition option as the special case of the barrier option. In the second part of this article, we employ the pricing formula of the barrier to derive the value of the National Finance Stabilization Fund, and then analyze the impact of the NFSF to the market. Our results reveal that when the benchmark market is not shifted by the bad news, then the NFSF may advance and stabilize the stock price index. In fact, many new style derivatives have the characteristics like barrier option, for example, a convertible bond with forced convert clause, which is a up-and-out call. Other course like bankruptcy costs, agency problems, and contingent liabilities etc, which can all be solved by the pricing formula in our discussion. We hope that results and the process in this article are helpful in solving above questions.

The number of insurance company has grown rapidly in Taiwan due to insurance deregulation since 1992. The main challenge insurance industry face is the declination of profit due to the increasing of competitors. The operator of insurance company is able to face this question and offer the solution, then a company has better solvency. So we explore two issue, one is to investigate the relationship between asset risk and capital adjustment decision in Taiwan¡¦s life insurance industry from 1993 to 2005, and the other is to provide some empirical evidences of retention limit of excess of loss reinsurance in Taiwan¡¦s property insurance industry. In the first issue, a life insurance company is in less risk and has better solvency when it has more capital or higher ratio of capital; however, this also brings higher opportunity cost which means in long run, the average profit will be lower. There is no conclusion how to balance the relationship between capital adjustment and risk taking decision in life insurance industry though this topic is intensively discussed these days. Therefore, with the methodology of panel data threshold regression, we divide life insurance companies into two categories according to ¡§life insurance and annuity insurance premiums to total premiums ratio¡¨. One is life insurance Company of indemnification, and the other is the one of savings. In conclusion, we identify the negative correlation between capital ratio and risk of life insurance company of indemnification and the positive correlation between capital ratio and risk of life insurance company of savings. In the second issue, because of the increase of natural disaster in Taiwan recently, the property insurance company has to face what the reinsurance companies are not willing to underwriter, so excess of loss reinsurance has become the viable solution in Taiwan¡¦s property insurance industry. We apply extreme value theory to the tail of Taiwan property insurance claim for VaR estimation and calculate retention limit of excess of loss reinsurance. The empirical results show that the distribution of Taiwan property insurance claim is fat-tailed. We suggested using Generalized Pareto Distribution (GPD) to model the data with extreme loss and conclude retention limit of excess of loss reinsurance.

This thesis includes two topics. The first topic is a CMOS SRAM using dynamic threshold voltage wordline-transistors, which is focused on high speed applications. The second one is a high voltage generator for FLASH memories. The generated high voltages are applied to the wordline controlled transistors during access and verification operations. By taking advantage of the large current provided by low Vth and low leakage current provided by high Vth, a CMOS SRAM using dynamic threshold voltage wordline transistors is presented. The design of a 4-Kb SRAM is measured to possess a 2.2 ns access time, and consume 43.6 mW in the standby mode. The highest operating clock rate is estimated to be 667 MHz. A high voltage generator using 4 clocks with two phases is presented to provide a high voltage supply required by FLASH memories during programming mode and erase mode operations. The circuit is implemented by TSMC 0.25um 1P5M CMOS process. It can provide as high as +11.7 V and -11.6 V by given VDD=2.5 V.

Abstract The electrical pitting often occurs at the bearing of the ro-tating machinery due to the actions of the shaft voltage and the shaft current resulting in the arcing effect on the lubricated surface and causing the bearing failure. Since the mechanism of the electrical pitting cannot be microscopically observed in process, it is difficult to prevent the bearing damage. Hence, this study uses a static electrical pitting tester with sub -micrometer accuracy to experimentally investigate the effects of supply voltage, supply current, oil film thickness, and ad-ditive on the threshold condition of electrical pitting under the conventional bearing material pairs. Moreover, according to the SEM micrograph and EDS analysis, the mechanism of the pitted surfaces is investigated. According to the experimental results and the surface ob-servations of steel/steel pair using a paraffin base oil, three electrical pitting regimes are found under the influences of shaft voltage and oil film thickness, namely, pitting, transition, and no-pitting regimes. In the electrical pitting regime, the interface voltage, interface impedance, and interface power increases slightly with increasing oil film thickness at a certain supply current. However, the interface voltage and interface power increases with increasing supply current, and the inter-face impedance decreases with increasing supply current at a certain film thickness. Furthermore, the pitting area versus the interface power relationship is a cubic function. According to the experimental results and the surface ob-servations of babbitt alloy/steel pair using a paraffin base oil, two electrical pitting regimes are found under the influences of shaft voltage, oil film thickness, and melting point of material, namely, pitting and no-pitting regimes. The mechanism of electrical pitting on the babbitt alloy surface is significantly influenced by the interface power and the oil film thickness. At the smaller oil film thickness, the eroded surface of babbitt alloy exhibits a concave crater with a few micro-porosity in the vicinity of center region with a plateau on its surrounding, especially at high supply current. The polished track can be observed at the plateau. A large amount of tin element trans-fers to the steel ball surface because the molten tin contacts the ball. At the higher oil film thickness, only a little amount of metal element transfers to each other. The major pitting area of the babbitt alloy is caused at the initial stage of the arc dis-charge. With increasing arc discharge time, the pitting area increases slightly, and finally reaches a saturated value. According to the experimental results and the surface ob-servations of babbitt alloy/steel pair using an additive of MoS2 in a paraffin base oil, two electrical pitting regimes are found under the influences of shaft voltage, oil film thickness, and particle concentration of additive, namely, pitting and no-pitting regimes. The area of pitting regime increases with increasing additive concentration and supply current. Fur-thermore, the ratio of pitting area to the interface power in-creases with increasing additive concentration and supply current at the oil film thickness smaller than 6 mm. However, this ratio increases rapidly to about 10 times with increasing additive concentration and supply current as the oil film thickness increases from 6 mm to 10 mm. This results from the molten plateau that directly connects two specimens, and the interface power is mainly consumed at the heating of the pla-teau and the interfacial materials. According to the above re-sults, the growth model of the plateau on the pitting surface is proposed at the lubricated condition using an additive of MoS2 in paraffin base oil.

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