The main advantage of wavelet transform relative to its Fourier analysis counterpart is its suitability to deal with transient signals. Furthermore, wavelet packet transform has very good frequency analytic ability with the result that it is developing in very fast speed and widespread researched and used in industry and academia. We study the characteristics of fiber optic sensors by applying wavelet transform. Hence, in this paper, the traditional Fourier analysis is taken as a basis, and the wavelet packet analysis is taken as a comparison. The major objects include: (1) calibration of hydrophones; (2) vibration measurement. In calibration of hydrophones, the experimental results show a 2.72 dB re V/£gPa inaccuracies and a 5.3 dB re V/£gPa standard deviation by Fourier analysis, but 0.5 dB inaccuracies and 1.6 dB re V/£gPa standard deviation by wavelet packet analysis. It shows that the wavelet packet analysis has better analytic ability than that of traditional Fourier analysis. In vibration measurement, we utilize FBG interferometers to measure stable vibration. The experimental results denote that wavelet packet analysis has excellent frequency analytic ability as Fourier analysis. Besides, in obtaining transient characteristic signals induced by falling stones, the results appear that wavelet packet analysis has better resolution and identification capability relative to Fourier analysis.

The high-throughput measurement devices for DNA, RNA, and proteins produce large amount of information-rich data from biological dynamic systems. It is a need to reverse engineering these data to reveal parameters/structure and behavior relationships implicit in the data. Ultimately, complex interactions between its components that make up a system can be better understood. However, issues of reverse engineering in bioinformatics like algorithms use, the number of temporal sample, continuous or discrete type of input data, etc. are discussed but merely in the validity problem. We argue that, since the data available in reality are not so perfect, the result of reverse engineering is impacted by the un-perfect data. If this is true, to know how this impacts the results of the reverse engineering and to what extent is an important issue. We choose the parameter estimation as our task of reverse engineering and develop a novel method to investigate this validity problem. The data we used has a minor deviation from real data in each data point and then we compare the results of reverse engineering with its target parameters. It can be realized that the more error in data will introduce more serious validity problem in reverse engineering. Three artificial systems are used as test bed to demonstrate our approach. The results of the experiments show, a minor deviation in data may introduce large parameter deviation in the parameter solutions. We conclude that we should not ignore the data error in reverse engineering. To have more knowledge of this phenomenon, we further develop an analytical procedure to analyze the dynamic of the systems to see which characteristic will contribute to this impact. The sensitivity test, propagation analysis and impact factor analysis are applied to the systems. Some qualitative rules that describe the relationship between the results of reverse engineering and the dynamics of the system are summarized. All the finding of this exploration research needs more study to confirm its results. Along this line of research, the biological meaning and the possible relationship between robustness and the variation in parameters in reverse engineering is worth to study in the future. The better reverse algorithm to avoid this validity problem is another topic for future work.

Risk-based corrective action (RBCA) is rapidly becoming an accepted approach for the remediation of contaminated sites. Under a RBCA approach, the risks to human health and the environment associated with a contaminated site are evaluated and appropriate corrective measures are taken as needed to reduce risk to acceptable levels. A series of standard guides of RBCA have been developed by American Society for Testing and Materials (ASTM). The major tasks of this study were to (1) perform the sensitiveness analysis to evaluate the effectiveness of each input parameter on the calculated risks, (2) application of Monte Carlo simulation using a statistic software (@RISK) to analyze the distribution probability of inhalation risk, (3) conduct a risk evaluation and risk calculation at a chlorinated-compound contaminated site. Results from the sensitiveness analysis show that the major factors, which play important roles in the risk evaluation including sources of air pollution, vapor transportation rate, pollutant volatilization rate, length and direction of wind, distance of pollutant transport, width of pollution source, and groundwater flow velocity. Results from the Monte Carlo simulation show that the carcinogenic risk is about 15¡Ñ10-6 when the accumulation rate is 95% via inhalation. Moreover, the carcinogenic risk is about 31¡Ñ10-6 when the accumulation rate is 95% via ingestion. The calculated risk levels are higher than the requirement for minimum target risk level (cancer risk of 1x10-6) described in Taiwan¡¦s ¡§Soil and Groundwater Remediation Act¡¨. Results also show that the hazard index of non-carcinogenic risk is about 0.5 via the route of inhalation, which is higher than the minimum target risk level of 1. Moreover, the hazard index of non-carcinogenic risk is about 1.3 via the route of ingestion, which is lower than the acceptable level of 1. Results from the case study show that the major pollutant exposure routes at this chlorinated-compound contaminant site include inhalation of contaminant vapor and groundwater ingestion. Therefore, the input parameters affect the calculated risks include daily intake of drinking water, groundwater infiltration, groundwater flow velocity, aquifer depth, and distance of pollutant transport. Based on the results of risk assessment, it is very important for the decision makers to incorporate remedial activities including institutional controls, engineering controls, and remediation programs from RBCA results. This study provides a streamlined process and guidelines of developing the risk-based decision-making strategy for contaminated sites in Taiwan.

Four wheeler is one type of the transportation vehicle which be widely used. Good or bad performance of the vehicle steering system has the decisive influence regarding security of the driver operation and the vehicle travel. Therefore, the purpose of this article is to establish the kinematic analysis theories of the vehicle steering system. And an improvement design theory of size synthesis are proposed to develop a set of user-friendly computer aided analysis and design program. At First, this article collects the related literatures and papers to understand the research technique and the design direction of vehicle steering mechanism. Second, establish the location analysis theory, the rotation torque analysis theory, the mechanical advantage theory and other performance¡¦s calculation formula with regard to ¡§Rocker Shaft Type Connecting Rod Vehicle Steering¡¨ and ¡§Rack and Pinion Type Connecting Rod Vehicle Steering¡¨ which are the most widely used. Third, establish a set of user-friendly computer aided kinematic analysis program by using the VB.NET computer programming language. And then propose a systematized movement design procedure, and establish the optimization size synthesis design theory by using the gene calculation method. Afterwards, carry on the sensitivity analysis in view of the each design variable of the steering mechanism with the orthogonal array table, and establish the kinematic improvement design program. Finally, separately aim at the two Vehicle Steering mechanisms, design a new group mechanism¡¦s size, whose steering performance is better than the original mechanism¡¦s size.

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In this thesis, the aluminum nitride (AlN) thin film was selected as a sensing membrane for the H+ ion-sensitive field-effect transistor (ISFET). The AlN thin films were prepared by a rf sputtering technology on the reference electrode/electrolyte /AlN /SiO2/p-Si/Al structure. The capacitance-voltage (C-V) measurement was used to detect the H+ ion concentration and the C-V characteristic curves were obtained in the different pH buffer solutions. On the other hand, AlN thin films were also prepared on the double layer structure of AlN/SiO2 gate ISFET devices. After packaging, the current-voltage (I-V) measurement with a PID temperature controller was utilized to measure a series of the I-V characteristic curves. The threshold voltage can be obtained to evaluate the pH sensitivity in the different pH buffer solutions. Additionally, the effects of non-ideal factors, such as temperature effect, drift and hysteresis phenomenon on the characteristics of the ISFET are also measured, analyzed and compared with other sensing materials. According to the experimental results, it can be found that the ISFET based on aluminum nitride thin film has a superior high pH sensitivity of approximately 50~58 mV/pH at 25¢J. The drift and hysteresis are dependent on the H+ ion concentration in pH=1~11, in which the drift rate increases with the pH value increased and the hysteresis magnitude depends on the measuring time and route. It is found that the hysteresis widths measured in pH=7®3®7®11®7 cycle at 960s, 1920s and 3840s loop time are 1.0, 1.5 and 4.5 mV, respectively. When the temperature effect was considered, it was found that the ISFET could be operated at 5~65¢J, in which, the pH sensitivity increased as the ambient temperature increased with the temperature coefficient of sensitivity of about 0.13 mV/pH¢J. In addition, the output voltage of AlN pH-ISFET can be obtained by a constant current constant voltage (CCCV) read out circuit with a fairly linear response, stability and reproducibility in the pH measuring cycle. From the characteristics mentioned above, the AlN thin film can be as a sensing membrane for pH-ISFET applications.

A distributed fiber optic sensor with the ability of detecting and locating intruders on foot and vehicles over long perimeters (>10 km) was studied. The response of the sensor to people walking over or near it and to vehicles driving nearby was observed and analyzed. The sensor works on the principle of phase sensitive optical time domain re ectometry, making use of interferometric effects of Rayleigh backscattered light along a single mode fiber. Light pulses from a highly stable Er:doped fiber laser emitting single longitudinal mode light and exhibiting low frequency drift are passed through one end of the buried fiber. The backscattered light emerging from the same fiber end was monitored using a photodetector. The phase changes produced in the light pulse due to the pressure of the intruder walking directly above or near the sensor or from the seismic disturbances created by vehicles moving in the vicinity of the sensor are detected using the phase sensitive Optical Time Domain Re ectometer (OTDR). Field tests were conducted with the sensing element as a single mode fiber in a 3-mm diameter cable buried at depths ranging from 8 to 18 inches in clay soil. It was observed that the sensor could detect intruders walking transverse to the cable line at a distance of 40 ft from it. A car moving at a speed of 30 mph on a rough road could be consistently detected up to a distance of 480 ft from the sensor, while a car driven on a smooth road 200 ft from the sensor could be detected only when passing through rough patches on the road. Tests were also performed with an intruder walking near the sensor while a car was driven at a speed of 30 mph on a rough road. The effect on the signal due to the intruder on foot could be distinguished clearly only when the car was at least 200 ft away from the sensor. The results in this thesis represent the first quantitative study of the sensitivity of the sensor under varied test conditions. It is expected that these findings will be helpful in the practical implementation of the long perimeter intrusion sensor along high security domains like national borders, military bases and government buildings.

Risk-based corrective action (RBCA) is rapidly becoming an accepted approach for the remediation of contaminated sites. Under a RBCA approach, the risks to human health and the environment associated with a contaminated site are evaluated and appropriate corrective measures are taken as needed to reduce risk to acceptable levels. A series of standard guides of RBCA have been developed by American Society for Testing and Materials (ASTM). The main task of this study was to conduct a risk assessment at a site contaminated with chlorinated organic compounds. The studied site had a chlorinated organic compound leakage incident, which caused groundwater contamination. The contaminants of concern included trichloroethylene (TCE) and dichloroethylene (DCE). The concentrations of TCE and DCE exceeded the control standards of 0.05 and 0.07 mg/L, respectively. The contamination has a tendency to move downstream along with groundwater. The goals of this study were to: (1) conduct risk assessment at the site, and to evaluate the risk of downstream acceptor; (2) analyze the carcinogenicity risk and the possible pollution transmission pathway to provide the management personnel a basis for future site screening, planning and technical improving; (3) evaluate the effect of natural attenuation (NA) processes on risk reduction; and (4) apply Monte Carlo analysis method to conduct uncertainty analysis at the site. In this study, RBCA Tool Kit for Chemical Release, 1.3 edition established by Groundwater Service, Inc. was applied for risk assessment. Moreover, the health risk assessment stimulation system developed by the Taiwan Environmental Protection Administration was also applied to conduct risk assessment simulation for comparison. The commercial software @RISK and Microsoft¡¦s EXCEL spreadsheet was used to conduct Monte Carlo analysis to analyze risk probability distribution. Results show that the health risk assessment result has indicated that the main risk at this site was through groundwater exposure pathway. If the biodegradation process occurs, the contaminant plume will be controlled and the risk will be reduced. Thus, the total carcinogenicity risk and hazard index (HI) of the downstream residential area will be reduced to acceptable levels (cancer risk < 1 ¡Ñ10-5, and HI < 1). Results from the Monte Carlo simulation show that the carcinogenic risk is about 6.38¡Ñ10-6 when the accumulation rate is 90% via inhalation. The calculated risk levels are higher than the requirement for minimum target risk level (cancer risk of 1x10-6) described in Taiwan¡¦s ¡§Soil and Groundwater Remediation Act¡¨. Results also show that the hazard index of non-carcinogenic risk is about 3.28 via the route of ingestion, which is higher than the acceptable level of 1. Based on the results of risk assessment, it is very important for the decision makers to incorporate remedial activities including institutional controls, engineering controls, and remediation programs from RBCA results. This study provides a streamlined process and guidelines of developing the risk-based decision-making strategy for contaminated sites in Taiwan.

Owning to the heterogeneity of services, service failures are inevitable to happen in service encounters. Therefore, recovery efforts play important roles in mataining the relationship with customer. Recovery paradox (RP) refers to the situation in which the customer who experiences a failure followed by a superior recovery rates a service as high as or even higher than s/he would rate a service involving no failure. By contrast, Double deviation (DD) refers to the situation in which inappropriate and/or inadequate recovery results in magnification of the negative evaluation. The RP and the DD are essentially symmetrical because both of them represent a phenomenon in which the recovery contributes to customer¡¦s evaluation more heavily than the initial failure dose. Although numerous studies devotes to the question whether the RP and DD exist, very few are trying to answer the question of why they exist. Thus, the main purpose of this research is to conceptually and empirically compare the RP and the DD in order to uncover the potential asymmetry, as well as to understand why recovery influences evaluation more greatly? Because the investigated conditions are not easy to be identified in the real world, a scenario-based quasi-experimental design is chosen. The data is collected from customers actually engaged in the target services. Customers are asked to answer questions about an organization they have recently patronized and then evaluate experimentally-generated scenarios in a restaurant setting to understand whether a negative discrepancy can really magnify the customer¡¦s evaluation toward an identical following event. The result reveals that after a negative-discrepant first event, a positive-discrepant second event is evaluated more positively than non-discrepant second event, but a negative-discrepant second event is evaluated less negatively than a non-discrepant one. That is to say the result supports RP, but doesn¡¦t support DD.