Direct and seamless coupling of TiO2 nanotube photonic crystal to dye-sensitized solar cell: a single-step approach

A TiO(2) nanotube layer with a periodic structure is used as a photonic crystal to greatly enhance light harvesting in TiO(2) nanotube-based dye-sensitized solar cells. Such a tube-on-tube structure fabricated by a single-step approach facilitates good physical contact, easy electrolyte infiltration, and efficient charge transport. An increase of over 50% in power conversion efficiency is obtained in comparison to reference cells without a photonic crystal layer (under similar total thickness and dye loading).     

Performance of a solar dryer using hot air from roof-integrated solar collectors for drying herbs and spices

A solar dryer for drying herbs and spices using hot air from roof-integrated solar collectors was developed. The dryer is a bin type with a rectangular perforated floor. The bin has a dimension of 1.0 m×2.0 m×0.7 m. Hot air is supplied to the dryer from fiberglass-covered solar collectors, which also function as the roof of a farmhouse. The total area of the solar collectors is 72 m². To investigate its performance, the dryer was used to dry four batches of rosella flowers and three batches of lemon-grasses during the year 2002–2003. The dryer can be used to dry 200 kg of rosella flowers and lemon-grasses within 4 and 3 days, respectively. The products being dried in the dryer were completely protected from rains and insects and the dried products are of high quality. The solar air heater has an average daily efficiency of 35% and it performs well both as a solar collector and a roof of a farmhouse.     

MONITOR AND CONTROL OF DISCHARGE ENERGY DURING EDMING

A pulse energy at 100MHz is verified to be able to determine the normal and abnormal discharge during electrical discharge machining (EDMing). A band pass filter is designed to detect the energy at this frequency, and can verify which discharge pulses are normal and abnormal, respectively. A field programmable gate array (FPGA) is used to implement the discharge detection circuit, including detection of the time of ignition (T_d) and discharge high‐energy. Function analysis is used to design the proportional (P) T_d controller to allow the bounded variation of reference input and the feedback signals. Energy of about 100MHz can be maintained within a specified pulse width by regulating the position of the electrode, including a slight regulation and jump motion. The rate of erosion during the roughing and finishing of a die‐sinking EDM is confirmed to demonstrate the improvements obtained by the EDMing.     

Reliable interactive programming with modules

Interactive programming is a convenient programming style that supports fast prototyping and debugging but often results in a loss of modularity and security. This article addresses the problem of supporting reliable and modular interactive programming. A module system designed for interactive use is introduced. This module system supports separate compilation and automatic updating of module interfaces during program development. It also allows the programmer to obtain a fresh program state for reliable testing, eliminating the need to reload an entire program.A preliminary version of this article was presented at the 1992 ACM Conference on Lisp and Functional Programming.     

An inverted U-shaped patch antenna for compact operation

By using a novel inverted U-shaped radiating patch in place of the conventional planar patch, compact operation of air-substrate patch antennas is presented. The inverted U-shaped patch is formed by adding two downward rims at the two radiating edges of a planar rectangular or square patch. And owing to the added rims, the excited patch's surface current paths are lengthened, which effectively lowers the antenna's resonant frequency and results in large antenna size reduction (>50%). The proposed compact design has been successfully applied to air-substrate patch antennas fed by an aperture-coupled feed. In addition to large size reduction obtained, the proposed antenna with an air-substrate thickness about 5% the wavelength of the center operating frequency can have an impedance bandwidth (10-dB return loss) greater than 9%, a peak antenna gain of about 6.4 dBi, and good broadside radiation patterns with cross-polarization levels better than 20 dB in principal planes.     

A displacement‐based strength reduction factor for high‐rise steel moment‐resisting frames

A preliminary study of the ‘displacement‐based strength reduction factor’ for high‐rise steel moment‐resisting frames is presented in this paper. The base shear capacity required for a high‐rise steel building in a displacement‐based design can be estimated from the reduction of the displacement‐based elastic response. The conventional force‐based design procedure is still adopted as the initial stage of the displacement‐based design. To establish an empirical formula of the proposed displacement‐based strength reduction factor, non‐linear time‐history analyses of six moment‐resisting frames are investigated. The conventional ‘equal displacement rule’ and ‘equal energy rule’ are no longer held when the displacement limitations are considered. As a result, a modification for conventional strength reduction factors is proposed for further applications in displacement‐based design. An adjustment factor defined as ‘deformation energy ratio’, β, which is related to natural periods, is introduced. The final displacement‐based strength reduction factor is defined as a function of ductility demand, fundamental period and the deformation energy ratio. Copyright © 2006 John Wiley & Sons, Ltd.     

Molecular epidemiology of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae isolates in a district hospital in Taiwan

Thirty-one of 104 clinical isolates of Klebsiella pneumoniae collected over a period of 8 months were found to be putative extended-spectrum beta-lactamase (ESBL) producers. Isoelectric focusing and an iodine overlay agar method were used for preliminary identification of the ESBLs. They were further identified by DNA sequencing. Seventy-one percent of the isolates were found to produce SHV-5. The variation in the ESBL patterns of these isolates was slight, with only five patterns being identified. The strains were typed by pulsed-field gel electrophoresis (PFGE), and 16 different genotypes were identified. When the PFGE patterns were analyzed by the algorithmic clustering method called the unweighted-pair group method using arithmetic averages, five clusters were found. However, significant genetic variations were found among 11 isolates and between each cluster. A plasmid of 36 kb was found in all clinical isolates and in the transconjugants. Our results indicate that the increase in the number of ESBL-producing K. pneumoniae isolates in this hospital is due mainly to the dissemination of a resistance plasmid rather than to the clonal spread of a few epidemic strains.     

Autoimmune ovarian disease: mechanism of disease induction and prevention

Investigation of the versatile models for autoimmunity of the ovary and other selected organs has contributed to our understanding of the following aspects of autoimmunity: the mechanism of T cell molecular mimicry; T-->B epitope spreading, as a basis for autoantibody diversification, and as a link between organ-specific and systemic autoimmunity; the localization of genetic loci potentially influencing multiple autoimmune diseases; and the elucidation of regulatory T cells as a component of physiological self tolerance.