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111.
本文以济宁市网通线路工程整治为实例,分析了在当前电话用户相对稳定的情况下,通信公司再加大对通信线路工程整治的必要性、重点和意义. 相似文献
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114.
由各种电子元器件组成单元电路,由许多个单元电路组成具有特定功能的电路系统就是电子设备。当整个系统不能正常工作时,或达不到其主要性能指标时,说明有的单元电路出现了故障,需要我们检测出故障所在。 相似文献
115.
A new scan architecture for both low power testing and test volume compression is proposed. For low power test requirements,
only a subset of scan cells is loaded with test stimulus and captured with test responses by freezing the remaining scan cells
according to the distribution of unspecified bits in the test cubes. In order to optimize the proposed process, a novel graph-based
heuristic is proposed to partition the scan chains into several segments. For test volume reduction, a new LFSR reseeding
based test compression scheme is proposed by reducing the maximum number of specified bits in the test cube set, s
max, virtually. The performance of a conventional LFSR reseeding scheme highly depends on s
max. In this paper, by using different clock phases between an LFSR and scan chains, and grouping the scan cells by a graph-based
grouping heuristic, s
max could be virtually reduced. In addition, the reduced scan rippling in the proposed test compression scheme can contribute
to reduce the test power consumption, while the reuse of some test results as the subsequent test stimulus in the low power
testing scheme can reduce the test volume size. Experimental results on the largest ISCAS89 benchmark circuits show that the
proposed technique can significantly reduce both the average switching activity and the peak switching activity, and can aggressively
reduce the volume of the test data, with little area overhead, compared to the previous methods.
相似文献
Hong-Sik KimEmail: |
116.
Elliptical quantum corrals present interesting properties due to the combination of confinement and focalizing properties. We show here that two magnetic impurities located at the foci of the systems experience an enhanced interaction, as compared to the one they would have in an open surface. These impurities interact via a superexchange AF interaction J with the surface electrons in the ellipse. For small J they are locked in a singlet state, which weakens for larger values of this parameter. When J is much larger than the hopping parameter of the electrons in the ellipse, both spins decorrelate and form a singlet with the nearest electron, thus presenting a confined RKKY-Kondo transition. We can also interpret this behavior via the entanglement or von Neumann entropy between the localized impurities and the itinerant electrons of the ellipse: for small J the entropy is nearly zero while for large J it is maximum. 相似文献
117.
Jun H. Jeong Mohsen Kavehrad 《International Journal of Wireless Information Networks》2006,13(3):207-220
We consider a coded multiple-input multiple-output (MIMO) DS-CDMA system using layered space-time transmission in multipath wireless channels, where space-time signals from multiple antennas of multiple users propagate through rich scattering multipath fading. We propose a receiver employing iterative joint detection and decoding with a reduced-complexity detector using linear minimum mean squared error filtering with a priori information and parallel soft-input soft-output (SISO) decoders. Computer simulation results show that the proposed receiver for multi-user MIMO transmission provides high-spectral efficiency and performance approaching to single-user bound. Furthermore, the reduced-complexity receiver outperforms an iterative soft decision-directed maximal ratio combining (DD-MRC) receiver, RAKE receiver as well as a conventional non-iterative receiver. 相似文献
118.
提出一个基于第三方控制的量子双向传态方案:通信双方Alice、Bob和控制方Charlie事先共享一个六粒子团簇态,通信开始后,Alice、Bob分别对自己拥有的部分粒子作Bell基联合测量(BSM),若控制方同意双方通信,则对自己拥有的粒子对作测量,将粒子所处的态公布;通信双方根据控制方公布的测量结果,对各自的某些粒子作适当的幺正变换,即可在这些粒子上重建对方要传的态。由于加入了第三方的控制,双向传态的安全性得到了提高。 相似文献
119.
本文主要围绕全彩LED显示屏的功耗问题进行分析,着重讨论了显示屏节能标准制定过程中需要重视的几个问题,如标准视频源的选定、立体角的引用、亮度的科学测量、效率系数的计算,从而为制定LED显示屏功耗能效等级相关标准提供建议。 相似文献
120.
《Mechatronics》2014,24(8):1178-1188
This article presents the hybrid design and control of a quad-rotor system called Flymobile. Flymobile is a combined system of a mobile robot and a quad-rotor system aimed to perform both flying and driving tasks. Flymobile performs flying tasks in the same way as conventional quad-rotor systems while the tilting mechanism of each rotor allows Flymobile to navigate in its terrain for a driving task. The body frame with rotors is implemented by a calibration process through a test-bed equipped with a force sensor. The triangular wheel frame is designed to mimic motions of a mobile robot with three passive wheels. Sensor data of a gyro and an accelerometer are filtered and used for controlling the attitude of the system. Focusing on a practical approach of implementing a hybrid system, a non model-based approach is applied to control Flymobile. Experimental studies are demonstrated to show the feasibility of performing both driving and flying missions. 相似文献