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排序方式: 共有8993条查询结果,搜索用时 15 毫秒
991.
Fu-Tin Man 《Communications, IEEE Transactions on》1977,25(12):1448-1453
When an existing toll machine exhausts and a relief toll machine is added, rehoming of existing trunk groups is necessary. The intent of this paper is to determine rehoming programs whereby the present worth of the total trunk rearrangement cost is minimized while the total number of trunks to be rearranged at any stage of the program is constrained to lie within specified lower and upper limits. The rehoming program will specify the amounts of trunks to be rearranged and their corresponding timings for the rearrangements to take place. It is found that the choice of a proper rehoming strategy is critically dependent on the relative magnitude of the monetary discount rate compared to the traffic growth rate. When the discount rate matches the growth rate, any feasible rehoming strategy for any type of existing and relief machines is appropriate. If the discount rate is lower than the growth rate, it is more economical to rehome the maximum allowable amount of trunks as early as possible. On the other hand, if the discount rate is higher than the growth rate, the rehoming strategy is completely reversed. This case calls for a delay of as much rehoming as possible. However, the number of trunks to be rearranged during each stage of the rehoming program is bounded by the specified minimum allowable limit. 相似文献
992.
Goodman M. S. Sessoms A. L. Gabriel T. A. Bishop B. L. Eisenstein B. Wright S. C. Kephart R. D. 《IEEE transactions on nuclear science》1980,27(1):46-53
The computer code system CALOR has been used to simulate data taken with a large segmented liquid argon/iron calorimeter at Fermilab. The resulting energy and angular distributions along with the longitudinal and transverse shower shapes are compared to experimental data in the range 1-38 GeV. Results are presented extending the Monte Carlo simulations to 125 GeV. The energy resolution of an incident hadron can be determined with a resolution ?E/E = (7.6 + 29.2/?E)% and its direction with a resolution of ?(?) = 22.7 + 390/E) mrad (where E is in GeV). 相似文献
993.
994.
Gabriel Michael; Lambert Richard W.; Foster Kent; Orona Edward; Sparenborg Steven; Maiorca Renee R. 《Canadian Metallurgical Quarterly》1983,97(5):675
Bilateral electrolytic lesions of the anteroventral nucleus of the thalamus given after training impaired retention performance (extinction and reacquisition) of 12 male New Zealand White rabbits in a differential avoidance conditioning task. In addition, the lesions abolished the excitatory, discriminative multiple-unit discharges that had developed in the cingulate and retrosplenial cortices to the auditory CSs during the course of behavioral acquisition, prior to the induction of the lesions. The excitatory discharges were supplanted in the Ss with lesions by CS-elicited reduction of neuronal firing to levels below the prestimulus baseline. Lesions given to 8 Ss before training did not disrupt behavioral acquisition, but they did eliminate the excitatory tone-elicited neuronal discharges that normally occur in the cortex before and during training. The CS-elicited reduction of neuronal firing did not occur at the beginning of training in the Ss given lesions before training, but it developed during the course of training. The lesions did not eliminate the excitatory and discriminative neuronal activity of the prefrontal cortex. Results demonstrate the excitatory and discriminative neuronal discharges in the cingulate and retrosplenial cortices are critically dependent on the connections of these areas with the anterior thalamic nuclei. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Einordnung der freien ?stehenden“ Zugelemente aus Drähten zwischen Förderseilen und Spanngliedern, die Beanspruchungen der Zugelemente, ihre Konstruktionsart und ihr Tragverhalten, aus welchen sich die Anforderungen an den einzelnen Draht herleiten lassen. 相似文献
996.
The pulsed electron beam rf ion stroage system is used to study neon ions electron transfer,The rate coefficients for electron transfer of the neon ions with the neon gas are measured.the results are better than those in other ion storage system. 相似文献
997.
Gate oxide damage from charge entering through the top surface of the gate electrode during plasma ashing, ion implantation, and LDD spacer oxide etching was measured using antenna structures. Significant charge damage to the 9.0 nm-thick gate oxide was detected for each of these processes. The damage was reduced by using a protective dielectric layer, in this case a thermally deposited TEOS oxide over the polycide gate electrode before gate definition. The dielectric appears to block charge penetration into the antenna. Damage can be reduced further by increasing the thickness of the dielectric layer; for a sufficiently thick layer (about 150 nm), charge entering through the top surface of the antenna was effectively eliminated 相似文献
998.
Kwai Man Luk 《Antennas and Propagation, IEEE Transactions on》1994,42(6):852-855
A moment method analysis of an infinite array of wraparound microstrip antennas fed with idealized current probes on a cylindrical body is presented. The integral equation is formulated through the use of periodic grounded dielectric slab Green's function. The method accounts for the blind angles and allows efficient computation of the reflection coefficient at all other angles. Illustrative results are given 相似文献
999.
1000.
This study describes the translocation of the brain specific protein kinase C gamma isoenzyme (PKCgamma) in the hippocampus during food rewarded spatial learning. The holeboard test was used for spatial orientation, and immunoblot analysis was used for assessment of PKCgamma in cytosolic, membrane-inserted and membrane-associated fractions. Membrane-associated PKCgamma was increased during early acquisition of spatial learning, but not in a later phase of training. This transient and apparently temporary intracellular PKCgamma translocation was only observed in the posterior but not in the anterior hippocampus, and was only detected within 10 min after termination of the learning trial. This study supports the idea that PKCgamma is significantly involved in the biochemical events underlying learning and memory, notably during the period of novel information processing. The results further promote the hypothesis that the hippocampus is specifically involved in temporal information processing, which requires the engagement of PKCgamma. 相似文献