Accurate indoor geolocation is an important and novel emerging technology for commercial, public safety, and military applications. Since most wireless communication systems used for indoor position location may suffer from dense multipath situation, which leads to a severe degradation of position accuracy. The improved TDOA/AOA(Time Difference of Arrival/ Angle of Arrival) position location for indoor ultra-wide band (UWB) systems in the thesis improves the position accuracy of indoor location by using fine resolution of UWB signals. In the line of sight situation, by means of increasing angle of arrival (AOA) information to time difference of arrival (TDOA) based location to achieve the goal of accurate indoor geolocation and provides non-line of sight (NLOS) error mitigation for time measurement and AOA selection to suppress the impact to position accuracy in NLOS environment. Finally, the extended Kalman filter is used to perform position tracking of the target. In the simulations, the NLOS error in time measurement is produced according to the characteristics of indoor UWB channel. Several assumptions of NLOS errors are made in angular measurement. It is observed that proposed method efficiently mitigates the position error in NLOS environment, and detect if the NLOS exists between base station and mobile station immediately.

Abstract The fundamental purpose of this research is to discuss the solution strategies and error types when seventh-grade students in middle school solved simple equations with one unknown and application problems; we hope results can provide reference for teachers in remedial teaching and in improving instructional. The items in the examination paper used in this research were taken from 12 past papers of basic competency test in Taiwan (2001 to 2006, twice a year). The subjects were students from Kaohsiung City Y Middle School (City region), Kaohsiung County T Middle School (Ordinary town) and Pingtung County Z Middle School (Near seacoast) forming a convenience sample. The investigators selected 2 classes from each school by random, with a total of 188 students. The main results of this research are as follows: 1. There are ten questions and the average proportion of correct answers is 49.10%; it shows that, at least 51% students have difficulties in solving symbolic operation and linear equations with one unknown. 2. The solution strategy student used most frequently is Removal of Term. Equal Axiom and Enumeration Evaluation Method were used occasionally. No student used Substitution method, Reduction method and Hidden method. 3. The main error types are: missing knowledge of using symbol; do not understand meanings of symbols; combine dissimilar terms freely; do not understand the meaning of bracket; cannot do calculation involving bracket; and, cannot simplify equation etc. 4. The main reasons for failures are: do not understand the meaning of equation; do not understand combination rules of like terms, position of symbol, unknown variables; whether containing fractions in reducing equation will also cause an error. Keywords: linear equations with one unknown, solution strategies, error types.

Abstract With the processing of globalization and the large increases in international trade and openness, it is important to capture the business cycle correlation with the intimate countries for government to make better policies and keep the economy steady. This study investigated the changes in relationships between the G7 business cycle after the European integration. Choosing 1993 the Europe Union (EU) commencement as the segment, we separated the sample period into 1965:1-1992:4 and 1993:1-2006:4.We adopted kinds of unit root tests to exam if these variables were stationary and the Johansen co-integration analysis to test whether the stationary long-run equilibrium exist or not. With the consideration of long run information, the Vector Error Correction Model (VECM) was applied to study the relationship between the business cycles of United State, EU and the other G7 countries. By Johansen co-integration analysis, we found that the stationary long-run relationship did exist between their industrial productions¡]IP¡^. In addition, the VECM evidence supported the emergence of two cyclically coherent groups -- the Euro-zone and the English-speaking countries -- after the EU commencement in 1993. In conclusion, with the greater correlation of business cycles, the party in office should take account of the business cycle movement of the closed countries more deliberately in this regionalization era.

Since petroleum is a kind of exhaustive resource, it can not be regenerated after being consumed. And petroleum is distributed extremely uneven in the world, more than half of petroleum is distributed in the Middle East area. In the recent years, the oil price was so fluctuating and broke the record again and again. However, the productivity of petroleum in Taiwan is very low and we are a price taker. So it turns to be important that how the oil price affects the economy. According to Economics, high oil price often causes the staginflation. In the purpose of this study we examine the long run relationship between oil price and personal income in Taiwan by cointegration theory. And we find that there indeed exists a negative longrun relationship. In addition, we consider a nonlinear model, Threshold Vector Error Correction Model, to test a threhold effect in the long run relationship between variables. Finally we have a result that there is a threshold cointegrating relationship between the oil price and personal income in Taiwan.

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ABSTRACT Presently, many industrial applications of gear sets with skew axes, especially worm gear and hypoid gear, are most widely used. The main content of this thesis is to construct the contact analysis model of the line-contacted type tooth profile of gear sets with skew axes with assembly error. The influence of geometrical parameters of skew-axes gear to the transmission error is analyzed. The complex method for optimization is implemented to select the better skew-axes gear parameters with the best performance in transmission error with assembly error. To prove the presented analysis model, the optimized gear parameters are utilized to construct the solid model for analyzing the contact properties by using computer simulation program.

Current-controlled logic and single electron logic processors have been investigated with respect to thermal-induced bit error. A maximal error rate for both logic processors is regarded as one bit-error/year/chip. A maximal clock frequency and an information channel capacity at a given operation current are derived when a current-controlled logic processor works without error. An available operation range in a current-controlled processor with 100 million elements is discussed. The dependence of an error-free condition on temperature in single electron logic processors is derived. The size of the quantum dot of single electron transistor is predicted when a single electron logic processor with the a billion single electron transistors works without error at room temperature.

The emerging popularity and interest in Voice-over-IP (VoIP) has been accompanied by customer concerns about voice quality over these networks. The lack of an appropriate real-time capable infrastructure in packet networks along with the threats of denial-of service (DoS) attacks can deteriorate the service that these voice calls receive. And these conditions contribute to the decline in call quality in VoIP applications; therefore, error-correcting/concealing techniques remain the only alternative to provide a reasonable protection for VoIP calls against packet losses. Traditionally, each voice call employs its own end-to-end forward-error-correction (FEC) mechanisms. In this paper, we show that when VoIP calls are aggregated over a provider's link, with a suitable linear-time encoding for the aggregated voice traffic, considerable quality improvement can be achieved with little redundancy. We show that it is possible to achieve rates closer to channel capacity as more calls are combined with very small output loss rates even in the presence of significant packet loss rates in the network. The advantages of the proposed scheme far exceed similar or other coding techniques applied to individual voice calls.

We construct the multi-factor model using fundamental cross-sectional approach in the thesis. We adopt the principal of BARRA¡¦E3 for constructing our multi-factor model. In our study period, we finally obtain 34 significant explanatory factors including 7 risk indices and 27 industry factors. In particular, the industry factors are an important risk source of the stock returns. The explanatory power of the multi-factor model is 43.18% on average and it ranges from 12.89% to 82.35%. The study results can be considered satisfactory. Moreover, based on the multi-factor model, we construct the Taiwan Weighted Stock Index enhanced index fund by the tracking error minimization method in our study. Enhanced Index Fund was built to make use of both passive management and active management to construct a portfolio which has the similar characteristics but higher returns compared to benchmark index. Hence, we want to track the Taiwan Weighted Stock Index while producing at least 2% outperformance over the Taiwan Weighted Stock Index. Our empirical period is from January 2000 to December 2005 and the simulated period is from January 2006 to December 2007. The performance of our constructed Taiwan Weighted Stock Index enhanced index fund in the simulated period is better than the benchmark and the tracking error is 1.36%. We are satisfied with the study results.