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101.
羰基铁类随机混合吸波材料等效电磁参数的计算 总被引:3,自引:0,他引:3
本文为计及多重散射偶极子间的相互作用,引入参量εh和μh,导得一组公式。它不仅能计算铁氧体类也能计算羰基铁类的随机混合吸波材料的等效电磁参数,均与实验结果吻合良好。 相似文献
102.
The current-voltage characteristics of the P-N double quantum well resonant interband tunneling (RIT) diodes in InAlAs-InGaAs system have been improved in this letter. The peak-to-valley current ratio (PVCR) is as high as 144 at room temperature. As we know, this is the highest room temperature PVCR ever reported in any tunneling devices. Moreover, the influence of the central barrier thickness varying from 10 Å to 30 Å on the device characteristics is also studied 相似文献
103.
Implicit deregistration in a PCS network 总被引:1,自引:0,他引:1
Registration/deregistration is required in a PCS network when a portable moves between registration areas. Several schemes were proposed to deregister a portable after it moves out of a registration area (RA). A simple scheme called implicit deregistration totally eliminates network traffic due to deregistration. However, this scheme may delete valid registration records. Thus, the size of a registration database must be sufficiently large to ensure low probability that a valid registration record is deleted. This paper describes an analytic model to determine the size k of the registration database for an RA in the implicit deregistration scheme. If the expected number of portables in an RA is N, then our study indicates that good performance can be achieved if k≃5N 相似文献
104.
Chan K.T. Chin A. McAlister S.P. Chang C.Y. Liu J. Chien S.C. Duh D.S. Lin W.J. 《Electron Device Letters, IEEE》2003,24(1):28-30
Very-low-transmission line noise of <0.25 dB at 18 GHz and low power loss /spl les/0.6 dB at 110 GHz have been measured on transmission lines fabricated on proton-implanted Si. In contrast, a standard Si substrate gave much higher noise of 2.5 dB and worse power loss of 5 dB. The good RF integrity of proton-implanted Si results from the high isolation impedance to ground, as analyzed by an equivalent circuit model. The proton implantation is also done after forming the transmission lines at a reduced implantation energy of /spl sim/4 MeV. This enables easier process integration into current VLSI technology. 相似文献
105.
Shaofeng Wang Yuan Hu Zhihua Lin Zhou Gui Zhengzhou Wang Zuyao Chen Weicheng Fan 《Polymer International》2003,52(6):1045-1049
Acrylonitrile–butadiene–styrene (ABS)/montmorillonite nanocomposites have been prepared using a direct melt intercalation technique by blending ABS and organophilic clay of two different particle sizes: OMTa (5 µm) and OMTb (38 µm). Their structure and flammability properties were characterized by X‐ray diffraction, high resolution electronic microscopy (HREM), thermogravimetric analysis (TGA) and cone calorimeter experiments. The results of HREM showed that ABS/5 wt% OMTa nanocomposite was a kind of intercalated–delaminated structure, while ABS/5 wt% OMTb nanocomposite was mainly an intercalated structure. The nanocomposites showed a lower heat release rate peak and higher thermal stability than the original ABS by TGA and cone calorimeter experiments. Also, the intercalated nanocomposite was more effective than an exfoliated–intercalated nanocomposite in fire retardancy. Copyright © 2003 Society of Chemical Industry 相似文献
106.
107.
Designing circuits with partial scan 总被引:1,自引:0,他引:1
Agrawal V.D. Kwang-Ting Cheng Johnson D.D. Sheng Lin T. 《Design & Test of Computers, IEEE》1988,5(2):8-15
In this scan design methodology, only selected faults are targeted for detection. These faults are those not detected by the designer's functional vectors. The test generator decides exactly which flip-flops should be scanned using one of two methods. In the first method, all possible tests are generated for each target fault, and the set of tests requiring the fewest flip-flops is selected. In the second method, only one test is generated for each fault, and the use of flip-flops is avoided as much as possible during test generation. Examples of actual VLSI circuits show a savings of at least a 40% in full-scan overhead 相似文献
108.
Location management of correlated mobile users in the UMTS 总被引:1,自引:0,他引:1
Rung-Hung Gau Chung-Wei Lin 《Mobile Computing, IEEE Transactions on》2005,4(6):641-651
In this paper, we propose concurrently searching for correlated mobile users in mobile communications networks. Previous work either focuses on locating a single mobile user or assumes that the locations of mobile users are statistically independent. We first propose a mobility model in which the movements of mobile users are statistically correlated. Next, we use the theory of Markov chain to derive the joint probability density function of the locations of mobile users. In addition, we propose a novel approach to discover the correlations among the locations of mobile users without explicitly calculating the joint probability density function. Our simulation results indicate that exploring the correlations among the locations of mobile users could significantly reduce the average paging delay and increase the maximum stable throughput. 相似文献
109.
J. R. He G. C. I. Lin 《The International Journal of Advanced Manufacturing Technology》1992,7(4):210-217
A computerised trace method has been developed for determining the relationships of assembly requirements with design dimensions
and tolerances of the components in an assembly, and the relationships of design specifications and machining allowance requirements
with manufactured dimensions and tolerances of the component in a process plan. This method traces from the proposed components
or planned operations only the dimensions and tolerances that affect the given requirement, and therefore the equations for
design or for manufacture can be established simultaneously and accurately. Hence it is possible to establish constraints
for the optimisation of dimensions and tolerances for design or for manufacture. 相似文献
110.