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961.
The primary visual sources of depth and size information are binocular cues and motion parallax. Here, the authors determine the efficacy of these cues to control prehension by presenting them in isolation from other visual cues. When only binocular cues were available, reaches showed normal scaling of the transport and grasp components with object distance and size. However, when only motion parallax was available, only the transpont component scaled reliably. No additional increase in scaling was found when both cues were available simultaneously. Therefore, although equivalent information is available from binocular and motion parallax information, the latter may be of relatively limited use for the control of the grasp. Binocular disparity appears selectively important for the control of the grasp. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
962.
The class of linear stochastic dynamic systems is defined, such that the laws of the probability distribution of values of output signals of a system are determined by its equations complying with the case of the absence of random disturbances. These distribution laws are found to be similar to the quantum laws of the distribution values of observable physical quantities. On this basis, a possibility of the definition of the quantum systems as systems of this class is investigated. It is shown that the theoretical proof of some axioms of quantum mechanics and new facts requiring the experimental verification follow from this definition.  相似文献   
963.
964.
A detailed study on the leverage of high-fT transistors for advanced high-speed bipolar circuit applications is presented. It is shown that for the standard ECL (emitter-coupled logic) circuit, the leverage of high fT is limited by the passive resistors (emitter-follower resistor and collector load resistor) and wire delay, especially in the low-power regime. For the standard NTL (nonthreshold logic) circuit, the leverage is higher due to its front-end configuration and lower power supply value. As the passive resistors are decoupled from the delay path in various advanced circuits utilizing active-pull-down schemes, the leverage of high FT becomes more significant  相似文献   
965.
隧道受震破壞調查分析與修復管理案例   总被引:1,自引:0,他引:1  
就隧道震後之災損模式進行統計與災損原因研判,並利用數值分析方法研判安全性,就結構加固等改善措施之設計考量作詳細說明;另由於隧道結構物的損壞範圍大,且修復經費受限,必須藉由定期檢测進行長期維護管理,以防範意外發生。於此,利用Vidco-GIS自動化影像地理资訊系統之e化新技術,以動態及靜態影像紀錄隧道災損狀況,同時亦整合建置前期設計、施工圖及定期維護等資料,相關成果以資料庫方式纳入日常維護管理,以有限人力有效率地進行維護管理紀錄並随時掌握現況供作決策之明確參考。  相似文献   
966.
BiCMOS standard cell macros, including a 0.5-W 3-ns register file, a 0.6-W 5-ns 32-kbyte cache, a 0.2-W 3-ns table look-aside buffer (TLB), and a 0.1-W 3-ns adder, are designed with a 0.5-μm BiCMOS technology. A supply voltage of 3.3 V is used to achieve low power consumption. Several BiCMOS/CMOS circuits, such as a self-aligned threshold inverter (SATI) sense amplifier and an ECL HIT logic are used to realize high-speed operation at the low supply voltage. The performance of the BiCMOS macros is verified using a fabricated test chip  相似文献   
967.
The authors report the implementation of deep-submicrometer Si MOSFETs that at room temperature have a unity-current-gain cutoff frequency (fT) of 89 GHz, for a drain-to-source bias of 1.5 V, a gate-to-source bias of 1 V, a gate oxide thickness of 40 Å, and a channel length of 0.15 μm. The fabrication procedure is mostly conventional, except for the e-beam defined gates. The speed performance is achieved through an intrinsic transit time of only 1.8 ps across the active device region  相似文献   
968.
969.
Hydrogen Permeability of Borosilicate Glasses   总被引:1,自引:0,他引:1  
Borosilicate glass-forming compositions R2O – B2O3 – SiO2 – RaOb (R — Li, Na, K; Ra — Zn, PbO) are investigated. A correlation-regression analysis of the criteria (the silicate modulus, the oxygen number, the structure cohesion factor, the relative molar volumes of the components) affecting the hydrogen permeability of glasses is carried out. The tendency for permeability variations depending on the component composition and the above specified criteria is identified.  相似文献   
970.
This paper gives an overview of the experimental results obtained by the method of MHD modeling in thin electrolyte layers and used to solve problems connected with the appearance of monotonic and vibrational instabilities. Primary consideration is given to the generation and interaction of transient vortex processes. As examples, the results of the investigations of flows in systems of two, three, and four vortices and periodic vortex structures, as well as of flows in the presence of obstacles of different permittivity modeling plants or technogenic screening devices intended to protect objects against pollution are presented. We consider the ways of using the results obtained in studying natural phenomena and in solving engineering-technical problems connected with mass and heat transfer and electrotransmission.  相似文献   
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