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In this thesis, two-dimensional floating pier consists of single rectangular impermeable pontoon and rigid beam is studied. The purpose of this study is to present a theoretical solution for linearlized problem of incident waves acting on a floating pier with pile-restrained. All boundary conditions are linearlized in the problem which is separated into a scattering problem and radiation problem with unit motion amplitude. The method of separation of variables is used to solve for velocity potentials. For the radiation problem with unit heave and rotate amplitude, the boundary value problem with nonhomogeneous boundary condition beneath the structure is solved by using a solution procedure proposed by Lee(1995). By calculating wave force from velocity potential, and equations of motion of the floating structure, an analytic solution for the problem is developed. At last, using finite element method to calculate the dynamic analysis on the pile acting by the pontoon and incident waves.

Abstract The interaction among the tooth wear, dynamic loads, and its corresponding frequency spectrum variation in a spur gear pair is investigated in the dissertation. A mathematical model for the dynamic responses of a profile shifting involute gear pair is derived. For simplicity, a two-step mesh stiffness model is proposed to approximate the load sharing and the time-varying stiffness effects in a mating gear pair. The analytic solutions for the dynamic responses of this simplified dynamic model are derived in both time and frequency domains. The effect of the tooth wear on the spectrum variation has been illustrated analytically. The amplitude and frequency modulations introduced from the periodic load fluctuation have also been discussed. In order to characterize the time-varying mesh stiffness, frictional coefficient, damping ratio, temperature rise and load sharing effects between engaged teeth, a computational algorithm with the quasi-linear iteration procedure is developed to include above instantaneous parameters in the teeth engagement process. The tooth wear equation proposed by Flodin and Andersson (1997) is employed to simulate the mild wear process for an engaging gear pairs. The interactions between the tooth wear and the dynamic loads for the Steel/Steel, POM/POM, Nylon/Nylon and Steel/Nylon gears pair have been studied numerically. Numerical examples indicate that the proposed models are valid for gear pairs with different materials.

Abstract Wideband-CDMA (WCDMA) is a kind of third-generation wireless communication system. It can provide multi-rate services and fast transmission with wideband technology. To improve the solution of no enough wireless bandwidth currently, the 3G communication systems have been researched and developed in several leading countries recently. WCDMA adopts a kind of new spreading codes named Orthogonal Variable Spreading Factor codes (OVSF codes) that have advantages of dynamically variable rates and keeping orthogonality. OVSF codes can provide different data transmission rates by assigning codes with different lengths. By building a code tree, we can discuss some better schemes to assign available data rate. In this paper, we propose an efficient channel assignment scheme that can decrease the call blocking rate and complexity of channel reassignment procedure. Based on the properties of the binary code tree, we use code merge scheme to decrease channel reassignment rate and call blocking rate. This will efficiently improve the performance of channel assignment and spectral efficiency. Simulation results show that the proposed scheme has expected results.

The purpose of this study is to analyze the stress effect of the shaft, the head speed of the golf club, and the reaction force of the arm as well as the wrist under the process of the down swing. By using two softwares, the researcher conducted the study. First, I-DEAS software was used to model the club head with shaft. Next, Dyna3D software was used to analyze the swinging condition. After that the golf club and ball were placed in the three dimensional space and analyzed the dynamic behavior with the field of gravity. In order to simulate the action of swing of the golf club, the driving moment was input to the arm and the wrist. Through changing the thickness of the shaft, three different flexibility and weight of the shaft was specified. Later on, the researcher discussed the swing effect of differently flexible shaft and weight of the shaft. From the result of analysis, stiff shaft resulted in stable swing but lower head speed under the same driving moment. By contrast, the soft shaft generated higher head speed and dynamic loft angle but it resulted in less stable club head traveling path. Besides, the stiff shaft generated higher resultant force and moment to the arm and the wrist under the same driving moment. It is believed that this study will provide some reliable computer simulation data for the reference in golf sport.

We use dynamic hedging to replicate the short put positions of common stocks and thelong put positions of equity index. The strategy is developed based on the fact that the volatility of average constituent stocks is greater than that of the index, and the aggregate movement of the constituent stocks becomes the movement of the index. Therefore, we expect the long-short volatility strategy to deliver stable returns. In this study, we first employ Monte Carlo simulation methods to create paths for the underlying securities and the corresponding index. Then, we use Black-Scholes delta-neutral dynamic hedging strategy to create synthetic options for the long-short put positions.Specifically, we conduct the dynamic replication strategy to form long put option of TSEC Taiwan 50 equity index and short options of its constituent stocks. Finally, we pick the TSECTaiwan Mid-Cap 100 Index and replicate the long-short volatility strategy again. This time the target constituents screening criteria are high beta and high historical volatility. The empirical studies show that: (1) The correlation coefficients between stock pairs are reciprocally related to the standard deviations of strategy returns. (2) The main source of losses is performance deviation of the price of small-sized stocks and the index. (3) The return of the strategy for portfolios excluding small cap stocks will be improved. (4) The loss will decline if we apply short strip strategy on those stocks which prices perform worse than the index. (5) The higher the volatility of the stocks we select, the greater the dynamic hedging premium we can get. (6) If we pick the high beta stocks to avoid the trend of stock prices diverging from the index, then the strategy yields higher returns.

Because the relatively long headers in voice packets may cause unnecessary waste in network bandwidth, in this Thesis, we propose a dynamic MUX/DEMUX mechanism to compress the overhead headers in the VoIP packets. The proposed mechanism can dynamically adjust the length of the compressed VoIP packets for multiple VBR voice connections in a mixed WLAN and WiMAX environment. QoS in terms of voice jitter can be guaranteed after the multiplexed voice packets are de-multiplexed. To validate the proposed mechanism, we implement two VoIP MUX/DEMUX gateways on Linux platform and place them in a mixed WLAN and WiMAX (IEEE 802.16a) network at NSYSU campus. On the VoIP MUX/DEMUX gateways, we implement four functions; (i) the header formats of two different mini compressions, (ii) the mechanism of compressing voice packets, (iii) multiple waiting buffers, and (iv) the mechanism of dynamically adjusting waiting time of voice packets from different sources. According to the experimental results, the proposed VoIP MUX/DEMUX mechanism has shown that it can substantially save WiMAX bandwidth and consistently stabilize packet arrival interval (PAI) of voice packets under different levels of background traffic (constant or burst). Thus, the QoS of voice communications are guaranteed through our proposed mechanism.

In ordert to increasing the capacity of stocking and integration in the process of optimizing the internal cost in steel industry. The cost of material profolio is usually being ignored during opmization. Experiences-based decision paten still being carried out in material profolio in this industry.Thus the Inventory and Manufacture cost are losing inadvertently. This study aims at obtaining the minimum material profolio cost so that we provide a model concerned with cost and element limitation of target product.Using dynamic programming into material-profolio decision making process. We divided material profolio into three steps, transforming the productive limitations into mathematic constrains,and implememting by software.The real-case data is given to estabilish the model database.Comparing our data with the real data,we found that with the approach, we significately reduced and the cost and variety of material profolio in different critiria