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11.
A configurable nonlinear filter generator is proposed. The nonlinear function employed is key controllable. By changing the key, a different sequence will be obtained. Simulated results show that an optimal linear complexity profile of the sequence can be generated 相似文献
12.
Images stored in resist for soft X-ray lithography or microradiography were found to show a background noise which limits the resolution. This is due to the statistically variable spatial distribution of the photons incident on the resist surface. An estimate of the fundamental noise-limited resolution has been made from the experimental measurement of photon flux incident on the surface and the accurate development rate curves. Monochromatic radiation from a synchrotron source was used. 相似文献
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The effect of DC flux on the core loss is examined for the practical range of power and frequency. Relevant core loss equations are derived and applied to an optimization algorithm to determine the minimum core loss at a given ratio of s (DC flux density to AC peak flux density). It has been found that the curves of hysteresis loss density versus the ratio of s exhibit a peak at a critical ratio. Below or above this critical ratio, the loss density decreases drastically. On the other hand, the curves of eddy-current loss density versus the ratio of s exhibits a minimum point at a critical ratio. Below or above this critical ratio, the loss density increases gradually 相似文献
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Tien-Hsiang Sun Chao-Weng Cheng Li-Chen Fu 《Industrial Electronics, IEEE Transactions on》1994,41(6):593-601
In this paper, a timed-place Petri net (TPPN) model for flexible manufacturing systems (FMSs) is constructed, which contains two major submodels: the stationary transportation model; and the variable process flow model. For multiple automated guided vehicle (AGV) systems, the authors embed a simple rule and introduce a push-AGV strategy in a TPPN model to solve the collision and traffic jam problems of such vehicles. Since a firing sequence of the TPPN from the initial marking to the final marking can be seen as a schedule of the modeled FMS, by using an A* based search algorithm, namely, the limited-expansion A algorithm, an effective schedule of the part processing can be obtained. To show the promising potential of the proposed work, a prototype FMS is used as a target system for implementation. The experiment results assert that the job-shop scheduling problem can always be satisfactorily solved 相似文献
18.
Ma Z.J. Chen J.C. Liu Z.H. Krick J.T. Cheng Y.C. Hu C. Ko P.K. 《Electron Device Letters, IEEE》1994,15(3):109-111
It has been reported that high-temperature (~1100°C) N2 O-annealed oxide can block boron penetration from poly-Si gates to the silicon substrate. However, this high-temperature step may be inappropriate for the low thermal budgets required of deep-submicron ULSI MOSFETs. Low-temperature (900~950°C) N2O-annealed gate oxide is also a good barrier to boron penetration. For the first time, the change in channel doping profile due to compensation of arsenic and boron ionized impurities was resolved using MOS C-V measurement techniques. It was found that the higher the nitrogen concentration incorporated at Si/SiO2 interface, the more effective is the suppression of boron penetration. The experimental results also suggest that, for 60~110 Å gate oxides, a certain amount of nitrogen (~2.2%) incorporated near the Si/SiO2 interface is essential to effectively prevent boron diffusing into the underlying silicon substrate 相似文献
19.
An analytical expression for both band-to-band and band-trap-band indirect tunnelings is used to study the gate-induced drain leakage (GIDL) current of MOSFETs measured before and after hot-carrier stress. The voltage and temperature dependence of GIDL are characterized. Both results show that interface traps situated near the midgap participate in the conduction of GIDL, and band-trap-band indirect tunneling could be the major mechanism. This is further supported by the fact that the percentage increase in GIDL induced by hot-carrier stress is about the same as the corresponding increase in interface-trap density. On the other hand, under low-field conditions, trap-assisted Poole–Frenkle emission dominates over tunneling for temperatures even well below room temperature. 相似文献
20.
Ching-Hsue Cheng 《Microelectronics Reliability》1994,34(12)
In this paper, we propose a new method to analyze fuzzy consecutive-k-out-of-n:F system reliability using fuzzy GERT. The triangular fuzzy numbers are used to fuzzify probabilities of the consecutive-k-out-of-n:F system and the interval arithmetic, α-cuts and an index of optimism λ are applied to compute fuzzy consecutive-k-out-of-n:F system reliability on fuzzy the GERT network. Futhermore, we can obtain all computation results by “MATHEMATICA” package. 相似文献