Tree series transformations computed by bottom-up and top-down tree series transducers are called bottom-up and top-down tree series transformations, respectively. (Functional) compositions of such transformations are investigated. It turns out that the class of bottomup tree series transformations over a commutative and complete semiring is closed under left-composition with linear bottom-up tree series transformations and right-composition with boolean deterministic bottom-up tree series transformations. Moreover, it is shown that the class of top-down tree series transformations over a commutative and complete semiring is closed under right-composition with linear, nondeleting top-down tree series transformations. Finally, the composition of a boolean, deterministic, total top-down tree series transformation with a linear top-down tree series transformation is shown to be a top-down tree series transformation.

Digital predistortion is one of the most cost effective ways among all linearization techniques. However, most of the existing designs treat the power amplifier as a memoryless device. For wideband or high power applications, the power amplifier exhibits memory effects, for which memoryless predistorters can achieve only limited linearization performance. In this dissertation, we propose novel predistorters and their parameter extraction algorithms. We investigate a Hammerstein predistorter, a memory polynomial predistorter, and a new combined model based predistorter. The Hammerstein predistorter is designed specifically for power amplifiers that can be modeled as a Wiener system. The memory polynomial predistorter can correct both the nonlinear distortions and the linear frequency response that may exist in the power amplifier. Real-time implementation aspects of the memory polynomial predistorter are also investigated. The new combined model includes the memory polynomial model and the Murray Hill model, thus extending the predistorter's ability to compensate for strong memory effects in the power amplifier. The predistorter models considered in this dissertation include both even- and odd-order nonlinear terms. By including these even-order nonlinear terms, we have a richer basis set, which offers appreciable improvement. In reality, however, the performance of a predistortion system can also be affected by the analog imperfections in the transmitter, which are introduced by the analog components; mostly analog filters and quadrature modulators. There are two common configurations for the upconversion chain in the transmitter: two-stage upconversion and direct upconversion. For a two-stage upconversion transmitter, we design a band-limited equalizer to compensate for the frequency response of the surface acoustic wave (SAW) filter which is usually employed in the IF stage. For a direct upconversion transmitter, we develop a model to describe the frequency-dependent gain/phase imbalance and dc offset. We then develop two methods to construct compensators for the imbalance and dc offset. These compensation techniques help to correct for the analog imperfections, which in turn improve the overall predistortion performance.

This study aims to analysis the seasonal fluctuation fisheries assemblages and fishing yield by weight and amount of per unit effort using commercial shrimp beam trawlers at the waters off Yunlin, southwestern Taiwan during 1997-2007. In total, 47 sampling cruises, 320 taxa belonging to 205 genera and 102 families were identified. Among these, twelve species occurred greater than 80%. The species number of teleost fish were the most in each sampling. The total fish yield were 3032.9 kg and 304,680 individuals in the sampling period. Shrimps, the target species of the commercial beam trawler, were collected 945.7kg (31.2% of the total fish yield) and 181,050 individuals (59.4% of the total fish yield) , both are the most dominant fish yield among the fishing communities. The teleost fish (865.2 kg, 31.2%) and snails (73,868 individuals, 24.2%) were with the most fish yield in terms of weight and amount, respectively. The dominant species presented a seasonal pattern with a highly oscillation yield in both weight and biomass of the species in the same season each year. Thirteen species were recognized as the mainly harvested animals in of seasonal the commercial shrimp beam trawler. This study also showed that the shrimp, Parapenaeopsis hardiwckii, from February to May, and the portunid crab, Portunus sanguinolentus, from August to November in each year had the most production by cluster analysis. Since, the coastal zone at Yunlin were selected for constructing as an industrial park from May, 1998. Therefore in related to the development of the industrial park, to compare the production of 13 mainly harvest animals individually between three industrial developmental stages (pre-development: 1997.1-1998.2, development: 1998.5-2004.12 and post-development: 2005.2-2007.12). The results showed that the production of 3 species, Tanea lineate, Glossaulax didyma and Parapenaeopsis hardiwckii, decreased significantly (p< 0.05), where as of 2 fish species, Arius maculates and Chrysochir aureus, increased. By in large the other species was not remained the same after the construction.

In this thesis, we propose different CORDIC architectures which solve the problems of long-latency in traditional pipeline CORDIC and the large-area cost in table-based CORDIC. The original table-based CORDIC can be divided into two stages, coarse stage and fine stage. We also propose the three-stage architectures, composed of traditional pipeline CORDIC, Rom/Multiplier architecture and linear approximation. Detailed analysis and estimation in area and latency of these different two-stage and three-stage architectures with different bit accuracy are given in order to determine the best architecture design for a particular precision. Finally, we choose one of the architectures to implement, compare the results, and show its applications.

Dissolved inorganic carbon (DIC), titration alkalinity (TA), and nitrate + nitrite (N+N) are measured from seasonal cruises at the time-series site SEATS in the northern South China Sea (18¢XN 116¢XE) between March 2002 and November 2004. The most distinctive feature of the annual nDIC (DIC normalized to a constant salinity of 33.8) cycle is an increase in wintertime and a decrease in summertime (March¡VAugust). The nDIC drawdown (-3.15 ¡Ó 2.23 mmol m-2 day-1) at summertime is mainly attributed to biological uptake of DIC. The other terms in the DIC budget calculation, i.e. the carbon fluxes of air-sea CO2 gas exchange, horizontal advection and vertical diffusion, are estimated to be -0.48 ¡Ó 0.31, -0.70 ¡Ó 0.86, and 2.50 ¡Ó 0.59 mmol m-2 day-1, respectively. Accordingly, results from the DIC budget calculation reveals a net community production (NCP) of -4.47 ¡Ó 1.98 mmol m-2 day-1. This calculated NCP from our data is in good agreement with the export and new production previously reported in the South China Sea. The consistency demonstrates that carbon system is almost in a steady state during summertime at SEATS. According to the Refield C : N ratio of 106 : 16, a flux of 0.67 ¡Ó 0.30 mmol m-2 day-1 of bioavailable nitrogen (Nbio) is needed to sustain the calculated NCP. The source terms in the Nbio budget calculation, i.e. the nitrogen fluxes of vertical diffusion, wet deposition, dry deposition and the contribution from the putative nitrogen-fixing cyanobacteria Trichodesmium and Richelia intra., are estimated to be 0.20 ¡Ó 0.04, 0.03 ¡Ó 0.01, 0.04 ~ 0.08, and 0.02 ~ 0.13 mmol m-2 day-1, respectively. It thus seems that all the source terms can only collectively account for 50 ~ 70% Nbio needed to support the estimated NCP. With this regard, unicellular cyanobacteria, which have been reported as an important N2-fixer in the subtropical North Pacific and identified by the nitrogenase genes (nifH) in the small size (less than 10

A bidirectional charge equalization circuit based on a bidirectional flyback converter topology is proposed to achieve the balance charging and discharging in series-connected battery bank. The circuit comprises a multi-input transformer, in which the batteries bank are connected to the primary windings via associated active power switches. During discharging, the batteries transfer energy to the load by activating the primary power switches. On the contrary, the batteries are charged by activating the secondary power switch in which the load is replaced by a power source. In order to simplify the control circuit and provide a flexible modulation, a digital signal processor (DSP) with the associated sensors and interface circuits are used as the control kernel. It is used to monitor the variations of battery voltages, and to regulate the duty ratio of the converter to provide a balance charging or discharging among the batteries. A battery bank with four series connected lead-acid batteries is used for illustrating the operation of the bidirectional charge equalization circuit. The experimental results advocate the applicability of the proposed approach.

It is always very difficult for the piano teachers to select appropriate teaching materials from many published method series. Assigning them to meet the need of each individual student is also a challenge. From the Chinese editions of several piano teaching materials, the following three elementary piano method series with similar attributes were selected as the base of this research: David Carr Glover Piano Library, Bastien Piano Library, and Alfred's Basic Piano Library. Through systematic analysis and comparison, this research reaches certain conclusions about the similarities and differences between these method series. The outcome of this research may help piano teachers in selecting method books more objectively and in improving their teaching techniques. This research compares three selected piano method series from the following four aspects: the longitudinal connection of core courses, the latitudinal connection of core courses, the functional techniques of core courses, and the degree of applicability and compatibility of the supplementary courses. Items being analyzed for the first two aspects are basic knowledge of piano playing, reading approach (including pre- staff reading, staff recognition, recognition of intervals, scales and tonalities), rhythmic training, playing techniques, and interpretation or expression. The results of all analyses are arranged in tabulate form with necessary comments. The functional techniques of core courses are summarized in four categories: sight reading, transposition, harmonization with primary chords as the accompaniment, and playing primary chord progressions. The degree of applicability and compatibility of supplementary courses in the selected series is also determined through the consideration of same items listed above. The findings of this research are threefold which reveal the uniqueness of each piano method series: 1.The "Piano Solo" book of the David Carr Glover Piano Library works better with its core courses in the latitudinal connections than the "Piano Repertoire" book. 2. The Bastien Piano Library is the only one out of the three selected series offering the functional techniques of sight reading and emphasizing the transposition technique. 3. The Alfred's Basic Piano Library performs the best in the longitudinal and latitudinal connections within its core lessons. Its selected supplementary courses and "Piano Lessons" books have the highest degree of applicability and compatibility.

Bargaining is a frequent activity in the shopping process, and it becomes a trend in electronic trading. In order to facilitate the on-line automatic bargaining activity, we develop three algorithms on the multi-agent system in this thesis. The first algorithm is the pattern generalization algorithm used for generalizing common patterns from transaction records. The second one is the pattern matching algorithm used on-line for identifying possible bargaining patterns from the pattern bases. To deal with the situation that there is no matched pattern, we design the dynamic price issuing algorithm using the utility theory to determine the seller¡¦s price and the timing a deal should be closed. We conducted a series of field experiments to evaluate the proposed algorithms on different seller¡¦s risk perspectives and compared the performance with conventional bargaining methods. The results show that the proposed methods obtain encouraging performance. The major contribution of this research is the initiation efforts on developing data mining algorithms for facilitating the price bargaining process for e-commerce.

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Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Sept. 18, 2008). PDF text: v, 109 p. : ill. ; 459 K. UMI publication number: AAT 3303652. Includes bibliographical references. Also available in microfilm and microfiche formats.