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1.
2.
A new excimer laser annealing (ELA) process that uses a floating amorphous-Silicon (a-Si) thin film with a multichannel structure is proposed for high-performance poly-Si thin-film transistors (TFTs). The proposed ELA method produces two-dimensional (2-D) grain growth, which can result in a high-quality grain structure. The dual-gate structure was employed to eliminate the grain boundaries perpendicular to the current flow in the channel. A multichannel structure was adapted in order to arrange the grain boundary to be parallel to the current flow. The proposed poly-Si TFT exhibits high-performance electrical characteristics, which are a high mobility of 504 cm/sup 2//Vsec and a low subthreshold slope of 0.337 V/dec.  相似文献   
3.
通过密度测定和DSC热分析,观测了超高分子量聚乙烯的辐射效应。实验结果表明:在吸收剂量0—1.13MGy范围内,密度随吸收剂量的增加而增大,熔化热和熔点也有所增加,特别是在低剂量范围内增加十分明显。以上结果都说明,超高分子量聚乙烯在辐照过程中,结晶在完善或有新的结晶形成  相似文献   
4.
We predict that, for wavelength division multiplexing optical-network applications, an asymmetrically dilated configuration of a 2×2 cross-connect is significantly better in terms of overall crosstalk when the levels of the bar-port crosstalk and the cross-port crosstalk are significantly different from each other, as is the case with optical-frequency filters which utilize grating-assisted coupling. As a verification, we present a simulation study with 2×2 polarization-diversified acousto-optic tunable filters. We present a recursive method to extend the principle of asymmetric dilation to larger-size cross-connect switches, and make a recommendation for an asymmetrically dilated 4×4 cross-connect configuration  相似文献   
5.
A multi-channel continuous toxicity monitoring system developed in our laboratory, based on two-stage mini-bioreactors, was successfully implemented in the form of computer-based data acquisition. The multi-channel system consists of a series of a two-stage minibioreactor systems connected by a fiber optic probe to a luminometer, and uses genetically engineered bioluminescent bacteria for the detection of the potential toxicity from the soluble chemicals. This system can be stably and continuously operated due to the separation of the culture reactor from the test reactor and accomplish easy and long-term monitoring without system shut down by abrupt inflows of severe polluting chemicals. Four different recombinant bioluminescent bacteria were used in different channels so that the modes of the samples toxicities can be reasonably identified and evaluated based upon the response signature of each channel. The bioluminescent signatures were delivered from four channels by switching one at once, while the data is automatically logged to an IBM compatible computer. We also achieved the enhancement of the system through the manipulation of the dilution rate and the use of thermo-lux fusion strains. Finally, this system is now being implemented to a drinking water reservoir and river for remote sensing as an early warning system.  相似文献   
6.
One requirement in designing and operating and operating system is to minimize the moisture change in stored grain. Moisture transfer during the aeration process is generally believed to be caused by the partial pressure difference between water in grain and water in air (P3-P4). A mathematical model was developed for rough rice, which predicts the partial pressure difference under various grain and ambient conditions. Observations of moisture change over 10 aeration tests confirmed the good correlation between sorption phenomena and partial pressure differences. Studies indicated that air relative humidity, air temperature, grain temperature and grain moisture are significant factors influencing the partial pressure differences and, thus, affecting  相似文献   
7.
白魁昌  尹国成 《核技术》1993,16(10):577-581
一种实验炼钢渣不同炉次样品的室温透射穆斯堡尔谱由两组裂距较大的四极分裂双峰和一组裂距较小的双峰组成,它们分别相应于具有不同微观环境的Fe^2+和Fe^3+。参照文献中已知FexO的穆斯堡尔谱数据,可确定该渣中的主要含铁相为FexO。X射线衍射相分析给出相同的结果。按亚谱的面积比计算出Fe^2+和Fe^3+的相对含量分别为85%和15%左右。进一步选取与样品晶体结构相联系的原子簇模型。用MS-Xa方  相似文献   
8.
In this paper, we study a manufacturing system consisting of two machines separated by two intermediate buffers, and capable of producing two different products. Each product requires a constant processing time on each of the machines. Each machine requires a constant non-negligible setup change time from one product to the other. The demand rate for each product is considered to be piecewise constant. Each machine undergoes failure and repair. The time-to-failure and time-to-repair are exponentially distributed random variables. The setup change and processing operations are resumable. We model our system as a continuous time, continuous flow process. An optimal control problem is formulated for the system to minimize the total expected discounted cost over an infinite horizon. To determine the optimal control policy structure, a discrete version of the problem is solved numerically using a dynamic programming formulation with a piecewise linear penalty function. A real-time control algorithm is then developed with the objective of maintaining low work-in-process inventory and keeping the production close to the demand. The algorithm uses a hierarchical control structure to generate the loading times for each product on each machine in real time and to respond to random disruptions in the system. The system is simulated using this algorithm to study its performance. The performance of the algorithm is also compared to alternative policies.  相似文献   
9.
The intent of this paper is to design a high-frequency transformer that is to be incorporated into the DC/DC pulsewidth-modulated switch-mode power supplies by two different technical approaches: a conventional wound-coil magnetic using copper wires, and a planar magnetic with layered copper tracks on laminated printed circuit board. Comparisons will be made between the two approaches in terms of profile: mounting height and surface area, and performance: power losses and efficiency. Other indicators like temperature rise and leakage inductance that causes electromagnetic interference, and cost, materials, and process fluency are also to be looked into. A sandwiched configuration for primary and secondary windings is proposed for the planar type. Issues arising and typical phenomena encountered will be discussed in detail. Primarily, the dominating factor in performance, cost effectiveness, or circuit compactness that restrains the choice of a particular type is to be evaluated.  相似文献   
10.
This paper examines bidding strategies in a bilateral market in which generating companies submit bids to loads. A load accepts electricity delivery from the generator with the lowest bid at its bid price as long as this price is not higher than the load's willingness to pay. Necessary and sufficient conditions of Nash equilibrium (NE) bidding strategy are derived based on a generic generating cost matrix and the loads' willingness to pay vector. The study shows that in any NE, efficient allocation is achieved. Furthermore, all Nash equilibria are revenue equivalent for the generators. Based on the necessary and sufficient conditions, this problem is formulated as an optimal assignment problem. Network optimization techniques are applied to calculate NE bid prices for the generators  相似文献   
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