This thesis work is in the area of modeling trust in multi-agent systems, systems of software agents designed to act on behalf of users (buyers and sellers), in applications such as e-commerce. The focus is on developing an approach for buyers to model the trustworthiness of sellers in order to make effective decisions about which sellers to select for business. One challenge is the problem of unfair ratings, which arises when modeling the trust of sellers relies on ratings provided by other buyers (called advisors). Existing approaches for coping with this problem fail in scenarios where the majority of advisors are dishonest, buyers do not have much personal experience with sellers, advisors try to flood the trust modeling system with unfair ratings, and sellers vary their behavior widely. We propose a novel personalized approach for effectively modeling trustworthiness of advisors, allowing a buyer to 1) model the private reputation of an advisor based on their ratings for commonly rated sellers 2) model the public reputation of the advisor based on all ratings for the sellers ever rated by that agent 3) flexibly weight the private and public reputation into one combined measure of the trustworthiness of the advisor. Our approach tracks ratings provided according to their time windows and limits the ratings accepted, in order to cope with advisors flooding the system and to deal with changes in agents' behavior. Experimental evidence demonstrates that our model outperforms other models in detecting dishonest advisors and is able to assist buyers to gain the largest profit when doing business with sellers. Equipped with this richer method for modeling trustworthiness of advisors, we then embed this reasoning into a novel trust-based incentive mechanism to encourage agents to be honest. In this mechanism, buyers select the most trustworthy advisors as their neighbors from which they can ask advice about sellers, forming a social network. In contrast with other researchers, we also have sellers model the reputation of buyers. Sellers will offer better rewards to satisfy buyers that are well respected in the social network, in order to build their own reputation. We provide precise formulae used by sellers when reasoning about immediate and future profit to determine their bidding behavior and the rewards to buyers, and emphasize the importance for buyers to adopt a strategy to limit the number of sellers that are considered for each good to be purchased. We theoretically prove that our mechanism promotes honesty from buyers in reporting seller ratings, and honesty from sellers in delivering products as promised. We also provide a series of experimental results in a simulated dynamic environment where agents may be arriving and departing. This provides a stronger defense of the mechanism as one that is robust to important conditions in the marketplace. Our experiments clearly show the gains in profit enjoyed by both honest sellers and honest buyers when our mechanism is introduced and our proposed strategies are followed. In general, our research will serve to promote honesty amongst buyers and sellers in e-marketplaces. Our particular proposal of allowing sellers to model buyers opens a new direction in trust modeling research. The novel direction of designing an incentive mechanism based on trust modeling and using this mechanism to further help trust modeling by diminishing the problem of unfair ratings will hope to bridge researchers in the areas of trust modeling and mechanism design.

The purpose of this paper is to design a laser scanning system for a high temperature and acidic environment to measure small-scale surface roughness of seabed and to collect information related to calcium carbonate debris. The study comprises two parts. One is to construct the hardware and software of the laser scanning system. Two is to test the system at sea. The system were tested at Kuishantao sea area, an area with many submarine springs. The temperature of the hot water from the submarine springs can be as high as 126¢XC. Key substances from this type of hot springs are surfur and air bubbles composed of CO2, N2, O2, SO2, and H2S. These chemicals make the sea water in this area acidic, and the pH value can be less than 2. In other words, this sea area is a high temperature and very acidic environment According the acidic resistant test result, the researchers decided to use Polypropylene (PP) as the material. The laser scanning system captures information automatically, and it uses industrial single board computer (PC104) as the control platform. The researchers selected red laser, which is monotonous, directional, and coherent Lithium batteries, can be recharged repetitively, were used to supply the power. High-precision positioning, high resolution, and with easy speed and angle control stepping motors were chosen for the system. For the software, the researchers chose the Window operating system. The hardware and software of this system are highly compatible. Operating the system is very intuitive because windows are used as the interface, and the hardware has high supporting capacity. This arrangement makes data analysis later on very convenient. Images acquired from conducting the actual experiment at sea that need to be processed. A CCD camcorder with fixed location and angle was used to capture images. With the high brightness characteristic of laser and simple threshold values for screening, the researchers got the pixel position of laser beans. Then a calibrated the camcorder was used to switch the pixel coordinates to obtain the actual size of the object.

Abstract National Health Insurance (NHI) has been implemented in Taiwan for nearly eight years; since then, over 96% of 23 million residents of Taiwan have benefited from this program, and 70% of them are satisfied. Recently, the growth rate of healthcare expenditure, however, has been phenomenally rapid, owing to the ageing population, the economic development, the expansion of health insurance, the increased supply of healthcare resources, and the innovation of medical technology. Under the circumstance that the bill of raising the insurance premium rate could not be passed by the legislative congress, the Bureau of NHI (BNHI) was forced to economize on expense to achieve the financial balance. Currently, the BNHI implements ¡§total amount control¡¨ to control the total medical claimed payments of each medical healthcare provider. Facing the increasing volume of documentary auditing, the BNHI has to make its efforts on how to improve its auditing efficiency. This is also one of the purposes of this thesis. This study aimed to establish a reasonable and fair auditing procedure of medical claim payment, termed ¡§medical claim payments auditing (MCPA) procedure¡¨. At the stage of professional auditing, adopted the ¡§MIL-STD-105E sampling plan¡¨ to select data for professional audit and used the auditing results as a payment criterion. To verify the adaptability of the MCPA procedure, the researcher used the data provided by the institutes of Kaohsiung and Pintong as simulation objects. Further, the estimated cost model was adopted to increase the possibility of using this procedure. The MCPA procedure consists of the following characteristics: 1) The number of sampling is much lower than that of the current system used by the NHI, thus the audit labor-force and time can be reduced significantly. 2) The incentive mechanism design encourages the healthcare providers to honestly apply their medical claim payments and avoids inappropriate healthcare services. 3) Adopting international standards of sampling technology makes the MCPA procedure trustworthy and simultaneously can reduce the implementing obstructs. Keywords: National Health Insurance; Sampling plan; Incentive mechanism design

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In the field of MEMS technology, all kinds of actuators are often regarded as the force source. However, some designs of actuators have good precision in position; the working distance to be driven is too short. Therefore, the actuator is often combined with a mechanism with displacement amplify function. The objective of this study is to synthesize the new pantograph mechanism using the concept of mechanism design according to the desirable motion and the requirement of the actuator. The cases of single degree-of-freedom and two degree-of-freedom are assumed simultaneously for the output of the basic design constraints so as to generate new pantograph mechanisms from the catalogue of kinematic chains. The suitable pantographs are then found out with the features such as: (1) single level plane using comb driver, (2) using compliant mechanisms as joints, and (3) suitable for MUMPs process. These constraints of design are considered as the procedures of process design, compliant mechanisms transformation, compliant joints design, actuator configurations design, FEM dynamic analysis and joint modifications. Finally, prototypes are evaluated and transform into planar micro compliant pantographs. Moreover, a test and a discussion of the displacement error are done under the consideration of the designed mechanism actuating using FEM analysis. The percentage of displacement error of planar micro compliant pantograph is defined, and the equation for estimating the percentage of displacement error is proposed so as to modify the motion error for controlling.

The aims of this research are to design an experimental testing mechanism and process for measuring the scattering strength and the pattern induced by an underwater target. The experimental data are to compare with existing theoretical results to insure the integrity of experimental design. The experiment is conducted in a water tank of dimension 1.8 m x 1.8 m x 1 m. The main work is to measure the sound field scattered by a copper sphere of diameter 60mm. There is one type of directive source employed in this analysis: 192 kHz iTP-192k transducer as the receiver and projector. The transducer transmits sine waves with the pulse duration roughly equal to 0.143 msec (equivalent to 64 waves). The scattering field theory is based on the formulation developed by Hickling (JASA, 1962, pp.1582-1592). In order to get more precise measurement results, this research designs a high strength and accurate mechanism with a ball-ring and aluminum workpieces. The mechanism can be used to measure target scattering signals circularly with same radius. The experimental process has demonstrated that it is more difficult to measure the forward scattering field than the backward scattering field, due to the fact that the forward scattering field is likely to be mingled with the direct waves. The comparison between experimental and theoretical results shows that the discrepancy in the backward scattering sector is within 3 to 4 dB; however, generally speaking, the variation of the curves show a good agreement. These results indicate that the design of this experiment is basically practicable, and with further improvements, it could be applied to measure other underwater targets. As a whole, the thesis is composed by basic theory deduction, experimental instrumentation, mechanism design, and experiment data analysis. The emphases place on the design and observation of the scattering experiment, data analysis, and further improvement.The aims of this research are to design an experimental testing mechanism and process for measuring the scattering strength and the pattern induced by an underwater target. The experimental data are to compare with existing theoretical results to insure the integrity of experimental design. The experiment is conducted in a water tank of dimension 1.8 m x 1.8 m x 1 m. The main work is to measure the sound field scattered by a copper sphere of diameter 60mm. There is one type of directive source employed in this analysis: 192 kHz iTP-192k transducer as the receiver and projector. The transducer transmits sine waves with the pulse duration roughly equal to 0.143 msec (equivalent to 64 waves). The scattering field theory is based on the formulation developed by Hickling (JASA, 1962, pp.1582-1592). In order to get more precise measurement results, this research designs a high strength and accurate mechanism with a ball-ring and aluminum workpieces. The mechanism can be used to measure target scattering signals circularly with same radius. The experimental process has demonstrated that it is more difficult to measure the forward scattering field than the backward scattering field, due to the fact that the forward scattering field is likely to be mingled with the direct waves. The comparison between experimental and theoretical results shows that the discrepancy in the backward scattering sector is within 3 to 4 dB; however, generally speaking, the variation of the curves show a good agreement. These results indicate that the design of this experiment is basically practicable, and with further improvements, it could be applied to measure other underwater targets. As a whole, the thesis is composed by basic theory deduction, experimental instrumentation, mechanism design, and experiment data analysis. The emphases place on the design and observation of the scattering experiment, data analysis, and further improvement.

Orthoses and auxiliaries are important to the people with lower limb disabled in their daily lives. The purpose of this study is to survey and discuss the existing walking auxiliary mechanism for the lower limb disabled people, and to design a new walking auxiliary mechanism to improve their walking gesture. In order to develop a new auxiliary mechanism for the people with lower limb disabled, commercial orthoses and patents are colleted, analyzed, classified, and compared to each others. Several interviews with a lower limb disablement are arranged and understand what they need. After integrating all the collected information as the design input, theories of mechanism structure synthesis, dimension synthesis, mechanism analysis are utilized to develop a mechanism design of auxiliary for lower limb disabled people to walk, to go up and down the stair. The Pro-Engineering, a CAD software, is used for solid modeling and the Visual Nastran, a CAE software, is applied for motion simulation. The results of computer simulations of walking and climbing up stairs are compared to that of video taken from the interviewed people.

Take the Quadrangular-Pyramid-Shaped Fiber Endface(QPSFE) and the Conical-Wedge-Shaped Fiber Endface(CWSFE) for example, the present procedure of grinding asymmetric optical fiber endface demands three to four steps. These steps take time and are lack of repeatability and high yield. Aim at the shortcomings, this study develops a set of mechanism to attach to the original optical fiber grinding machine. The mechanism makes the normal pressure between the endface and the grinding plate change periodically to modify the removing rate of the material, thus enables the clipped flat endface of the optical fiber be ground into an elliptic-cone-shaped in a single grinding step, and then becomes a lens after its tip being fused by the arc. This mechanism reduces the fabricating time and cost, and consequently improve the economic benefits as well by simplifying the complicated manufacturing processes that represented before. Besides, for its single-step grinding characteristic, the offset between the center of the fiber and the elliptic-cone can thus be slashed to promote the yield. This study reviews the anterior references, including the papers and the patents, to begin, and then proposes the current means to compare with. Its contents involve the development of the forming principle, which proposes how the variation of the normal pressure takes influence on the removing rate of the material, and the required mechanism for the design procedure. The mechanism, the research result, and those needed to be ameliorated will be demonstrated in the conclusion and discussion part, so as to offer the investigating direction in the future.

Mechanical grinding processes is the most popular way to fabricate the endface of optical fibers, although there are some other methods like chemical etching and leaser machining. Mechanical grinding has its uniqueness in cases of grinding Conical-Wedge-Shaped Fiber Endface¡]CWSFE¡^, polygon-cone-shape fiber endface and fiber endface with double-variable curvatures. Despite Mechanism Design Lab of National Sun Yat-sen university has successfully developed Unsymmetrical Fiber Endface Grinding Mechanism and Torque-Control Fiber Endface Grinding Mechanism in NSC 94-2212-E-230-005 and NSC 95-2221-E-230-020, it still face difficulties when fabricating the fiber endface with double-variable curvatures due to the mechanism constraints. In this study, the focus are concentrated on both the designing and implementing of a mechanism for grinding optical-fiber endface with double-variable curvatures, which controls Material Removal Rate by simultaneously and periodically adjusting the relative positions, as well as the normal pressure between the fiber endface and the grinding film. This study is composed of first, the reviewing the anterior references, both the papers and the patents, and then a series of engineering design methods, which involve the design requirements and constraints, conceptual design, evaluating alternatives, detail design, assembly and calibration. The mechanism, the research result, and those needed to be ameliorated will be demonstrated in the conclusion and discussion part, so as to offer the investigating direction in the future. It¡¦s believed that the grinding machine system developed in this study can be successfully applied to fabricating optical fiber lenses as well as different types of micro probes , micro electrodes, and micro spectroscopefors for other applications, with little adjustment of the jig and ferrule of this machine .

Certifiers have a crucial role in facilitating effective communication in the online and the traditional world. As a way of generating statistically meaningful information, certification has been adopted in financial statements evaluation and more recently in various online communities as well. This dissertation examines three related issues along this common theme: online reputation market, moderation in user-generated content, and strategic communications in the market for certifications, and consists of three essays. The first essay analyzes the impact of various dispute mechanisms on online identity trading. Online identities with a good reputation profile is a valuable and tradable asset. However, with free identity creation, there is room for low quality sellers to free-ride high quality sellers. When there is a lack of incentive for sellers to maintain a good reputation, identity trading becomes ineffective. This essay focuses on the role of an auditing system, such as eBay dispute center, and shows that even a small amount of objective information from the auditors can reverse the negative result and sustain reliable reputation and identity trading. The second essay investigates the impact of moderation on the quality of information in an user-generated content (UGC) environment. In most UGC communities, content contributors have incentive to publish biased or false information. For example, companies hire people to write positive reviews about themselves. This essay establishes a framework for the mechanism design of moderation, and provides insight on how to optimally allocate moderation resource. The third essay examines a market for certification and certifiers' strategic reporting behaviors. The central question is how to induce certifiers to provide statistically meaningful information to investors when they are paid by their client firms. We provide insights on how certifier competition plays an role in firms' certifier choice, how certifiers degrade their accuracies to achieve maximum profit, and how the legal environment impacts the information quality. / text