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51.
52.
Herner S.B. Bandyopadhyay A. Dunton S.V. Eckert V. Gu J. Hsia K.J. Hu S. Jahn C. Kidwell D. Konevecki M. Mahajani M. Park K. Petti C. Radigan S.R. Raghuram U. Vienna J. Vyvoda M.A. 《Electron Device Letters, IEEE》2004,25(5):271-273
A field-programmable, stackable memory cell using 0.15-/spl mu/m technology is demonstrated. Vertical polycrystalline silicon diodes are stacked on top of one another, with tungsten (with TiN adhesion film) interconnect wires. An SiO/sub 2/ antifuse film separates the top of each diode from the TiN-W films. The cell is programmed when sufficient biasing voltage is applied to break down the antifuse, connecting the diode to tungsten. The cell is unprogrammed when the antifuse is intact. Cell fabrication and performance are described. 相似文献
53.
Mendoza R. Reed J.H. Hsia T.C. Agee B.G. 《Signal Processing, IEEE Transactions on》1991,39(9):2108-2111
Two new blind adaptive filtering algorithms for interference rejection using time-dependent filtering structures are presented. The time-dependent structure allows the adaptive filter to outperform the conventional adaptive filter implemented with a time-independent structure for filtering of cyclostationary communication signals. At the same time, the blind adaption algorithms allow the filters to operate without the use of an external training signal. The first algorithm applies the CMA to an unconstrained time-dependent filtering structure. The second algorithm applies the CMA to a spectral correlation discriminator, which is constrained to select signals with unique spectral correlation characteristics. Using computer simulations, it is shown that the blind time-dependent filtering algorithms can provide mean-square errors (MSEs) and bit error rates (BERs) that are significantly lower than the MSEs and BERs provided using conventional time-independent adaptive filters. It is also shown that these processors can outperform the nonblind training-sequence directed time-independent adaptive filter 相似文献
54.
55.
Decision learning about production control as machines break down in a flexible manufacturing system
Kuo-Shong Wang Hung-Wei Hsia Zheng-Dao Zhuang 《International Journal of Flexible Manufacturing Systems》1995,7(1):73-92
During manufacturing, there are many situations that can affect production performance. Such situations include machine breakdowns, rush orders, order changes, and order delays. When such issues occur, one has to make decisions to try to maintain production efficiency.Human decisions tend to be too late and incomplete in such contingencies. Thus a system that can make better decisions in time to maintain production performance is needed. To achieve this objective, the intelligent decision system described in this paper integrates artificial intelligence, an optimization technique, and simulation to solve such problems. The decision-making logic of the intelligent decision system is described by event graphs. It imitates the manner of human thinking.Self-learning of the decision-making process is used to strengthen the decision quality. In this study, a method of rule induction is applied to build up the self-learning system. There are two subsystems included in this system. One is rule generation and the other is knowledge management. A case for machine breakdowns is presented and discussed. A series of tests designed to validate the self-learning system are presented. These demonstrate that a rule induction method is suitable for constructing the self-learning. 相似文献
56.
The spatial and temporal characteristics of slider motion resulting from writer-induced pole tip protrusion are studied. Head-disc
contact results from protrusion and the amount of contact is varied by varying the steady-state write current, the amount
of overshoot, and the write frequency, all of which change the amount of heat dissipated in the writer. We measure the resulting
slider motion via three orthogonal LDVs and a position sensitive detector to give five of the six possible degrees of freedom
of motion. We compare the relative magnitudes of motion in different directions and we explore how higher power gives more
continuous contact. We also investigate the time scales associated with protrusion and with air bearing pitch angle changes.
We measure the speed with which the writer protrudes and find that slider pitch angle change increases linearly with the amount
of current. 相似文献
57.
A new least squares solution for obtaining asymptotically unbiased and consistent estimates of unknown parameters in noisy linear systems is presented. The proposed algorithms are in many ways more advantageous than generalized least squares algorithm. Extensions to on-line and multivariable problems can be easily implemented. Examples are given to illustrate the performance of these new algorithms. 相似文献
58.
Klimek D. Hsia J. Jacob J. Trainor D. Duzy C. Hyman H. 《Quantum Electronics, IEEE Journal of》1981,17(9):1847-1855
Various kinetic issues that are important for modeling the performance of large-scale-size krypton fluoride lasers have been investigated. These kinetic issues include: electron quenching, photoionization from excited rare gas atoms, fuel burn-up, and the accessibility of higher lying levels of KrF* to be effectively stimulated by the laser cavity flux. The results of these studies have been incorporated into a laser kinetics code. Absorption and gain measurements have been carried out over a broad range of conditions to provide a data base to test the code's accuracy and to make subsequent refinements. The code projections for short-pulse operating conditions important for laser-fusion applications are presented. 相似文献
59.
Formal approach to scenario analysis 总被引:1,自引:0,他引:1
Scenarios offer promise as a way to tame requirements analysis, but progress has been impeded by the lack of a systematic way to analyze, generate, and validate them. The authors propose such a method and apply it to a simple PBX system. Their method has a formal mathematical base, generates precise scenarios, accommodates change, and keeps users involved in the process 相似文献
60.
YJ Wang SD Lee HC Lin HC Hsia FY Lee YT Tsai KJ Lo 《Canadian Metallurgical Quarterly》1993,18(1):101-105
The purpose of this study was to develop a model in which the regional pharmacokinetics of a drug in tumor and nontumorous tissue could be evaluated under a variety of physiological conditions. To this effect, the growth of a human choriocarcinoma cell line (JAR) was evaluated in pigs immunosuppressed with 25 mg cyclosporine/kg every 24 h. During an initial study, we demonstrated that suspensions containing approximately 3 million JAR cells with and without 1 million normal human fibroblasts injected s.c. into the inguinal region of pigs resulted in the growth of tumors consisting primarily of polygonal neoplastic cells. Multinucleate tumor cells, inflammatory cells, necrotic debris, and vascular endothelial cells were also present. Maximal tumor size was noted on day 12, after which time tumor regression occurred. The coinoculation of fibroblasts resulted in significantly larger tumors. Two single pedicle, axial pattern tubed flaps were created in the inguinal area of 4 pigs. JAR cells and fibroblasts were transplanted to one flap to allow for tumor formation. The other flap served as a nontumorous control. Both flaps were removed for perfusion with a physiological solution 11 days later. Glucose utilization, lactate concentrations, lactate dehydrogenase activities, and microscopic evaluation of skin samples were used to assess flap viability. All flaps remained viable for 8 h of perfusion. The only differences detected between nontumorous and tumor flaps was the initial perfusion pressure which was significantly lower in tumor flaps (P < 0.05). The isolated perfused tumor and skin flap is unique in that it consists of a tumor surrounded by normal tissue with an intact microvascular system and can be utilized to design regional pharmacokinetic studies describing drug distribution in tumor tissue. 相似文献