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101.
Cheng-Hsing Hsu Pai-Chuan YangHsi-Wen Yang Shu-Fong YanHsin-Han Tung 《Thin solid films》2011,519(15):5030-5032
Zinc niobium oxide (ZnNb2O6) thin films were grown on ITO/glass substrate by sol-gel process. Microstructure and surface morphology of the ZnNb2O6 thin films have been studied by X-ray diffraction and scanning electron microscopy. Optical properties of the ZnNb2O6 thin films were obtained by UV-visible recording spectrophotometer. The dependence of the microstructure, optical transmittance spectra, optical band gap on annealing temperature was also investigated. 相似文献
102.
103.
Yip CT Huang H Zhou L Xie K Wang Y Feng T Li J Tam WY 《Advanced materials (Deerfield Beach, Fla.)》2011,23(47):5624-5628
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). 相似文献
104.
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. 相似文献
105.
Yeou-Koung Tung 《Water Resources Management》1987,1(4):241-254
Like any other resources planning and management, groundwater management is performed in a stochastic environment in which the system itself involves a number of random elements. Consequences as a result of decisions made based on analyses are not certain. This paper presents a management model using the chance-constrained framework which explicitly considers the random nature of aquifer properties. The model enables the derivation of an optimal groundwater management policy that would satisfy required operation performance reliability. Furthermore, the chance-constrained model is extended to the multi-objective optimization framework in which a tradeoff between total water supply pumpage and system performance reliability is explicitly considered. The models are applied to a hypothetical example of a steady, nonuniform, homogeneous confined aquifer. 相似文献
106.
107.
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 (Td) and discharge high‐energy. Function analysis is used to design the proportional (P) Td 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. 相似文献
108.
109.
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. 相似文献
110.
Kin-Lu Wong Hao-Chun Tung 《Antennas and Propagation, IEEE Transactions on》2003,51(7):1647-1648
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. 相似文献