A non-quasi-static small-signal model for metal-semiconductor junction diodes

The quasi-static approximation, which assumes that free-carrier propagation delay in the semiconductor device is zero, is often used in device modeling. Consequently, the quasi-static model is adequate only for low-frequency excitations for which free-carrier propagation delay is very small compared to the variation of the excitations. This paper develops a non-quasi-static model suitable for metal-semiconductor junction diodes subjected to small-signal excitation. We show that the predictions of the non-quasi-static model agree more favourably with experimental data taken from Al---Si diodes than that of the quasi-static model, particularly when the frequency of the excitation is high.     

Simple narrow-linewidth 1.5 ?m InGaAsP DFB external-cavity laser

An external-cavity laser consisting of a 1.5 ?m-wavelength antireflection-coated DFB laser chip, a microscope objective and a mirror provides a stable, single-frequency, narrow-linewidth (?f=40 kHz) output. Because the laser operates in the strong feedback regime, it is immune to external optical perturbations. Single-longitudinal-mode operation is maintained by the DFB grating, and the linewidth is reduced by the extended passive cavity.     

箱式变电站箱内温升及变压器的负载率

箱式组合变电站箱内温的特点跟负载特性及箱壳的散热结构有关，而变电站内的电力变压器的负载率又跟箱内温升及箱壳的散热等级有关，本文给出了变压器负载率的计算公式和参考值。     

A dynamic paging scheme for long‐term evolution mobility management

In long‐term evolution, the service area is partitioned into several tracking areas (TAs), which comprise one or more cells (the radio coverages of base stations). The TAs are grouped into TA list (TAL). When an incoming call arrives, the network attempts to connect to the user equipment (UE) by paging the cells in the UE's TAL, which may incur large paging traffic that significantly consumes the limited radio resources. To resolve this issue, this paper proposes a dynamic paging scheme that determines the paging sequence of cells in real time according to the UE movement and call behavior. We compare the performance of the dynamic paging with that of the previously proposed Cell‐TA‐TAL (CTT) paging. Our study indicates that the dynamic paging outperforms the CTT paging when movement pattern is regular and the UE moves frequently. Copyright © 2013 John Wiley & Sons, Ltd.     

Whole-mount preparations of mouse lens epithelium for the fluorescent cytological study of actin

A technique is given for the preparation of a sheet of epithelial cells from the capsule of the crystalline lens. A new method is described for fixation and staining with fluorescent phalloidin or actin antibody in order to localize the actin cytoskeleton in this tissue. Optical section of the preparation resolves such actin features as apical polygonal arrays, sequestered actin bundles, perinuclear actin aggregates, observed here for the first time, and filamentous networks in the basal region of the cell. This method is superior to previous ones in its ability to preserve actin-abundant sectors distinctively.     

Multiple-User Data Acquisition and Analysis System

The nuclear physics program at the Brookhaven National Laboratory High Flux Beam Reactor (HFBR) employs a pair of PDP-11 computers for the dual functions of data acquisition and analysis. The data acquisition is accomplished through CAMAC and features a microprogrammed branch driver to accommodate various experimental inputs. The acquisition computer performs the functions of multi-channel analyzers, multiscaling and time-sequenced multichannel analyzers and gamma-ray coincidence analyzers. The data analysis computer is available for rapid processing of data tapes written by the acquisition computer. The ability to accommodate many users is facilitated by separating the data acquisition and analysis functions, and allowing each user to tailor the analysis to the specific requirements of his own experiment. The system is to be upgraded soon by the introduction of a dual port disk to allow a data base to be available to each computer.     

滚齿加工齿轮误差的矢量法分析

从共轭原理角度出发，采用矢量法分析了运动偏心下滚齿加工轮齿的本质，阐明了有运动偏心的情况下，滚切出的齿形是有误差的渐开线齿形。