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A superposition scheme for downlink multicell processing with finite backhaul capacity

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Journal of Southeast University(English Edition) 2017年第3期33卷 253-259页

作者： Yi Xiao Wu Mingzhan Liu Nan National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

In the scenario of downlink multicell processing with finite backhaul capacity in the case of two base stations and two mobile users, by regarding the channel as a multiple access diamond channel with two destinations, an achievability scheme that sends correlated codewords through the multiple access channel with common data is proposed. By considering the superposition structure, fully correlated codewords can be supported by the proposed scheme, which can benefit the system throughput in the case of a relatively-large-capacity backhaul. First, an achievable region for the achievable theory is given and it is proved from the perspective of information theory. Then, in the Gaussian scenario, a simulation combining dirty-paper coding and power allocating is provided for the achievable region. Simulation results demonstrate that when the backhaul capacity is relatively large, the proposed scheme outperforms the existing achievability scheme without the superposition structure.

关键词： multicell processing finite backhaul capacity superposition dirty-paper coding power allocating

爱立信GSM　multicell站系统简介

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移动通信 2001年第2期25卷 35-37页

作者：费国臻江苏省移动通信责任有限公司南通分公司江苏南通226001

本文介绍爱立信ＧＳＭＭｕｌｔｉｃｅｌｌ站系统的原理和两种基本类型的基站结构，以及安装中容易出现的一些问题。

关键词：爱立信 GSM multicell 移动通信基站系统

Studies of an LL-type 500 MHz 5-cell superconducting cavity at SINAP

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Chinese Physics C 2015年第4期39卷 67-72页

作者：侯洪涛马震宇毛冬青封自强罗琛是晶王岩李正徐凯赵玉彬郑湘赵申杰张志刚刘建飞 Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai Key Laboratory of Cryogenics & Superconducting RF Technology University of Chinese Academy of Sciences

A low loss- （LL） type 500 MHz 5-cell superconducting niobium prototype cavity with a large beam aperture has been developed successfully including the optimization, the deep drawing and electron beam welding, the surface treatment and the vertical testing. The performance of the fundamental mode was optimized and the higher order modes were damped by adopting an enlarged beam pipe for propagation. Surface preparation or treatment including mechanical polishing, buffered chemical polishing and high pressure rinsing with ultra-pure water and so on was carried out carefully to ensure a perfect inner surface condition. The vertical testing results show that the accelerating voltage higher than 7.5 MV was obtained while the quality factor was better than 1× 109 at 4.2 K. No obvious multipacting or field emission was found during the test. However, a quench happened while increasing the field a little higher than 7.5 MV that at present limited the cavity performance.

关键词： superconducting niobium cavity low loss multicell fabrication optimization vertical test

THE NEW SUPER-HIGH-SPEED DIGITAL CIRCUIT BASED ON LINEAR AND-OR GATES

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Journal of Electronics(China) 1995年第4期12卷 289-297页

作者：王守觉石寅吴训威金瓯 Institute of Semiconductors Academia Sinica Beijing 100083 Department of Electronic Engineering Hangzhou University Hangzhou 310028

The paper reveals the relation between the linear AND-OR gate and the emitter function logic. With theoretic calculation and PSPICE simulation, the paper proves that the linear AND-OR gates can work at super-high-speed and can be multi-cascaded. On the basis of analyzing the high-speed switch units which coordinate with linear AND-OR gates, two kinds of emitter coupled logic circuits are designed. The paper also discusses the design principles of super-high-speed digital circuits, and some examples of combinational and sequential circuits using linear AND-OR gate are given.

关键词： linear AND-OR gate Super-high-speed digital circuits DYL(Duo Yuan Logic, it means multicell type logic circuits

Numerical Analysis of the Transient Process of Flow and Heat Transfer at High Rayleigh Number in a Partially Open Habitat Heated from Above

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Open Journal of Fluid Dynamics 2019年第3期9卷 253-267页

作者： Kodjo Kpode Yawovi Nougbléga Cheikh Mbow Magolmèèna Banna Département de physique Université de Kara Kara Togo Groupe Phénomène de Transfert et Energétique Université de Lomé Lomé Togo Département de physique Université Cheikh Anta Diop Dakar Sénégal

In this work, we studied the thermoconvective instabilities in a pentagonal cavity containing a Newtonian fluid. The cavity provided with a side opening is uniformly heated from above by a constant heat flux. The natural ventilation phenomenon in the classic habitat of the hot climate is thus numerically analyzed with unsteady natural convection equations formulated with vorticity and stream-function variables. The finite volume predictions of two-dimensional laminar natural convection at high Rayleigh number are presented. Results show that the incoming fresh air and the hot air discharge begin with the late start of the convection. The phenomenon intensifies with time and the birth of instabilities improves the homogenisation of temperatures which imply the elimination of very cold and very hot areas. However, the competition between the incoming fresh air and the hot air expansion leads to a perpetual displacement of the thermal front. The cross-sections at the opening of the incoming fresh and outgoing hot air are time-varying and the penetration depth of the fresh air is highlighted by the large convective cells originated from the aperture. The non monotonic variation of the Nusselt number reflects not only the multicell nature of the flow but also expresses the heat lost by the active walls due to the fresh air.

关键词： Unsteady Natural Convection Natural Ventilation multicell Flow Nusselt Number