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111.
Soft errors in 16 Mbit dynamic random access memories (DRAMs) have been investigated using proton microprobes at 400 keV with a spot size of 1 × 1 μm2. The newly developed susceptibility mapping can reveal the correlation between the particle hit-position position and the susceptibility to soft errors in a DRAM. The cell-mode soft-errors were found to take place by the incidence of ions within 6 μm around a monitored cell. These errors would be induced by minority carrier diffusion in a lateral direction. This result manifests the possibility of multiple-bit errors by the incidence of an energetic particle. 相似文献
112.
Masahiro Ohshima Hiromu Ohno Iori Hashimoto Mikiro Sasajima Masayuki Maejima Keiichi Tsuto Tadaharu Ogawa 《Journal of Process Control》1995,5(1)
This paper describes the results of a joint university-industry study to control a fatty acid distillation sequence, which is plagued with severe disturbance problems. In order to solve the disturbance problem, a model predictive control algorithm is modified in terms of disturbance prediction. Assuming that the dynamics of the unmeasured disturbances is generated by an auto-regressive form, the dynamics of the disturbance can be adaptively identified by using time series data of prediction errors and inputs. Using an identified disturbance model with a process model, future outputs are predicted. Control actions are determined so that the predicted output is as close to the target value as possible. This modified model predictive control aglorithm is applied to a ratio control scheme for three distillation columns. The control system developed has been in use sucessfully for more than six years to produce commercial products. 相似文献
113.
114.
T Izawa M Morikawa M Inoue T Mizuta H Yamashita H Ohno T Komabayashi 《Canadian Metallurgical Quarterly》1995,45(6):1093-1100
Chronic exercise substantially shifted the dose-response curve for angiotensin II (ANG II)-induced contractions to the right with increases in the EC50 value in both endothelium-intact and endothelium-denuded aortae. An acute endurance exercise also caused a 3-fold increase in the EC50 value in both endothelium-intact and endothelium-denuded aortae from sedentary control rats. Whereas, no substantial increase in the EC50 value was observed in trained rats after an acute endurance exercise. Thus, chronic exercise attenuates ANG II receptor-mediated contraction of rat aortae. An acute exercise also caused the reduced responses to ANG II in sedentary control rats but not in chronically exercise-trained rats. 相似文献
115.
116.
We report a rare case of meniscal cyst from the posterior horn of the lateral meniscus, extending in the posterior intercondylar space of the right knee of a 15-year-old boy, in whom magnetic resonance imaging was very useful for evaluation. A cyst in this location has not been reported previously. The cyst was removed surgically, while preserving the lateral meniscus. A good result was obtained, and no recurrence has been seen in 12 months. 相似文献
117.
118.
Optimal training for block transmissions over doubly selective wireless fading channels 总被引:11,自引:0,他引:11
High data rates give rise to frequency-selective propagation, whereas carrier frequency-offsets and mobility-induced Doppler shifts introduce time-selectivity in wireless links. To mitigate the resulting time- and frequency-selective (or doubly selective) channels, optimal training sequences have been designed only for special cases: pilot symbol assisted modulation (PSAM) for time-selective channels and pilot tone-assisted orthogonal frequency division multiplexing (OFDM) for frequency-selective channels. Relying on a basis expansion channel model, we design low-complexity optimal PSAM for block transmissions over doubly selective channels. The optimality in designing our PSAM parameters consists of maximizing a tight lower bound on the average channel capacity that is shown to be equivalent to the minimization of the minimum mean-square channel estimation error. Numerical results corroborate our theoretical designs. 相似文献
119.
Theoretical procedures of first-principles calculations of phase stability and phase equilibria are summarized. The present
scheme is shown to be able to reproduce the transition temperatures with surprisingly high accuracy for Fe−Pd and Fe−Pt systems.
The main emphasis of the present report is placed on the extension of the first-principles calculation to transition dynamics
calculations. This is performed by combining the cluster variation method with the phase-field method via a coarse graining
operation. The time evolution process of antiphase boundaries associated with L10 ordering for Fe−Pd system is demonstrated.
This paper was presented at the International Symposium on User Aspects of Phase Diagrams, Materials Solutions Conference
and Exposition, Columbus, Ohio, 18–20 October, 2004. 相似文献
120.
We investigated theoretically a unique way to control the dispersion relation of electrons by using a novel double quantum well (DQW) structure, in which an in-plane periodic potential is introduced to one of the channels. It is demonstrated that the effective mass in this system can be abruptly changed by the gate-controlled resonant coupling, resulting in a switching of the channel current. We discuss also a few feasible schemes to achieve the effective mass modulation and their possible applications to the velocity modulation transistor. 相似文献