Dynamic lithium-ion battery model for system simulation

Presents here a complete dynamic model of a lithium ion battery that is suitable for virtual-prototyping of portable battery-powered systems. The model accounts for nonlinear equilibrium potentials, rate- and temperature-dependencies, thermal effects and response to transient power demand. The model is based on publicly available data such as the manufacturers' data sheets. The Sony US18650 is used as an example. The model output agrees both with manufacturer's data and with experimental results. The model can be easily modified to fit data from different batteries and can be extended for wide dynamic ranges of different temperatures and current rates.     

OA系统中的动态工作流模型分析

针对办公业务流程的多变性，研究了工作流技术在OA系统中的应用，对WFMC定义元模型作了适当的扩展，使之能够实现OA系统中工作流的动态管理。提出并建立了该工作流系统的数学模型。     

基于混合模式的网页过滤系统研究

网页过滤系统旨在帮助用户屏蔽不健康的网页。提出了基于混合模式的网页过滤模型，将传统的基于网址过滤和敏感词过滤的方法与基于文本分类的过滤方法结合起来。重点讨论了特征量选取、网页结构化信息利用等方面的改进措施。实验表明这种模型在保持易于实现的特点的同时，在速度和准确度方面都有不同程度的提高。     

HYPASS: an optoelectronic hybrid packet switching system

An architecture is presented for an optoelectronic hybrid packet switching system (HYPASS) for the distribution of multiple-bit-rate broadband services. HYPASS is based on an input-buffered/output-controlled arbitration protocol. The internal routing and interconnection utilizes a passive optical transport network with wavelength-tunable laser transmitters and fixed wavelength receivers. The single-stage multiwavelength optical interconnect provides an internally nonblocking network for large throughput routing of the bit-serial optical signals. An internal optical control network, with fixed-wavelength trouble receivers, sends output port information to the input nodes for arbitration and control. Packet buffer storage and control processing is performed by word-parallel electronic circuitry. The characteristics and device requirements for this design are presented along with results of a performance analysis of the arbitration and control protocol     

新型液压离合器液压操纵系统性能测试系统的设计

汽车新型液压离合器液压操纵系统几乎100%使用先进的工程塑料,克服了金属离合器总、分泵的缺点,产品可靠性高,耐久性寿命试验达150万次以上。为了能更好地对这种新产品进行研制和性能测试,需要自主开发一种适     

一种新型的商用车离合器执行机构系统设计

重型商用车的离合器自动离合执行机构一般采用电控气动式,然而气体本身存在可压缩性及易暴躁性,增加了控制的复杂程度,影响了离合器自动离合控制的精确性和接合柔顺性,进而影响换挡品质。针对那些问题,本文设计了一种新型的商用车离合器执行机构,并详细介绍了离合器执行机构系统的控制方案、系统组成、工作原理以及其控制单元的软硬件设计。     

一种非公路宽体自卸车AMT离合器电控操纵系统的设计

本文通过分析非公路宽体自卸车原有的离合器操纵系统存在的问题,设计了一种AMT离合器电控操纵系统,以STC89C52芯片为核心,采用一些新型的功能模块设计及电控操纵系统使系统自动化,是一种改进现有系统存在问题的新方案,对后期非公路宽体自卸车AMT电控操纵系统的设计有一定的参考意义。     

基于混合模式的油田自动化设备管理系统研究

针对油田自动化设备管理的具体业务,设计了自动化设备管理信息系统.该系统采用C/S与B/S相结合的模式,可以完成对自动化设备的运行数据进行全面管理,该管理包括从制定采购计划到采购入库、投入运行、调动设备、闲置及报废整个过程,并能通过WEB浏览的方式完成查询、分析、统计、通知发布和技术论坛等功能.最后,探讨了系统开发中角色授权和数据整理几个关键性技术问题.     

Dynamic simulation for analysis of hybrid electric vehicle system and subsystem interactions, including power electronics

Simulation tools for hybrid electric vehicles (HEVs) can be classified into steady-state and dynamic models, according to their purpose. Tools with steady-state models are useful for system-level analysis. The information gained is helpful for assessing long-term behavior of the vehicle. Tools that utilize dynamic models give in-depth information about the short-term behavior of sublevel components. In this paper, a dynamic model of a hybrid electric vehicle that includes fuel cells, batteries, ultracapacitors, and induction machine drives is presented. Simulation results of vehicle configurations with a battery, a fuel cell-battery combination and a fuel cell-ultracapacitor combination are discussed. The focus of the model is a detailed assessment of different subsystem components, particularly component losses.     

某飞机离合器试验台测控系统的设计

针对某飞机起动机部件中的离合器组件在手动模拟调试、人工观察信号判断其高转速与发动机脱开,和低转速与发动机再接通的测试过程中存在测试效率低、可靠性不高等问题,提出了一种采用了西门子变频器、交流电机、研华采集卡和工控机组成的自动测试系统。该系统可自动控制转速按设定的升降斜率运行,同时能自动捕捉离合器脱开、再接转速点的信号。经实际使用表明,系统运行性能良好,自动化程度高,提高了测试效率和可靠性。     

Dynamic voltage scaling for series hybrid amplifiers

We present an optimization of the voltage scaling algorithm in low power audio class-G amplifier for headphones application to allow longer playback time. The optimization approach minimizes the voltage difference between the internal audio amplifier power supply and its output signal over a large range of operating conditions. The modeling is based on a behavioral model enabling accurate and rapid evaluation of efficiency and audio quality with realistic input stimuli. The model validated in practice is used to optimize the voltage scaling using only few power supply levels. Thanks to a global search algorithm followed by a local one, the optimization gives the better parameters for voltage scaling algorithm while keeping a good audio quality. The proposed configuration increases the efficiency up to 48% at nominal operation.     

Dynamic generation of spin-wave currents in hybrid structures

Spin transport through the interface in a semiconductor/ferromagnetic insulator hybrid structure is studied by the nonequilibrium statistical operator method under conditions of the spin Seebeck effect. The effective parameter approach in which each examined subsystem (conduction electrons, magnons, phonons) is characterized by its specific effective temperature is considered. The effect of the resonant (electric dipole) excitation of the spin electronic subsystem of conduction electrons on spin-wave current excitation in a ferromagnetic insulator is considered. The macroscopic equations describing the spin-wave current caused by both resonant excitation of the spin system of conduction electrons and the presence of a nonuniform temperature field in the ferromagnetic insulator are derived taking into account both the resonance-diffusion propagation of magnons and their relaxation processes. It is shown that spin-wave current excitation is also of resonant nature under the given conditions.     

Lumped-circuit model for inductor-capacitor hybrid

The inductor-capacitor hybrid described by Reeves is analysed by a lumped-circuit model, in which the metal foils in the device have finite resistance. The earlier theory appears as a special case of the model, and some difficulties at the principal resonance are removed.     

Dynamic range of an optical amplifier cascade in an ASK system withsignificant phase noise

The authors present detailed results concerning the dynamic range of an amplitude-shift keyed (ASK) heterodyne optical communication system where the transmitted signal is impaired by significant amounts of laser phase noise. Theoretical results are evaluated for a system with up to ten in-line optical amplifiers and a significant influence of the laser phase noise is found for the maximum allowable transmission span and the dynamic range. With ten amplifiers, a linewidth of 11% of the bit rate causes the span to be reduced by 12.2 dB and the dynamic range to be reduced by 5.7 dB. The results have been confirmed using two amplifiers in a field trial experiment at a bit rate of 636 Mb/s with an IF linewidth of 70 MHz     

ADVISOR-based model of a battery and an ultra-capacitor energy source for hybrid electric vehicles

An energy source is the heart of a hybrid electric vehicle. If it is capable of supplying enough power at all times, then it is an adequate source. Major problems presently facing the industry include the size, cost, and efficiency of the energy source. The primary energy source presently used in automotive systems is a battery. In order to reduce the cost of the battery, the current needs to be decreased and stabilized so it is not very erratic. The purpose of this paper is to introduce and justify the use of a new model for an energy source: a battery in parallel with an ultra-capacitor. The ultra-capacitor can supply a large burst of current, but cannot store much energy. Conversely, the battery can store mass amounts of energy; however, without expensive and inefficient units, a battery cannot provide the current that the ultra-capacitor can. By combining the two energy sources in parallel, the storage and peak current characteristics desired can be achieved. The standards of the vehicle are not degraded, allowing this to be a promising technique to incorporate into hybrid electric vehicles to reduce their cost and increase the efficiency of their energy-source system.     

基于AT89C55WD的磁粉离合器智能检测系统

磁粉离合器是一种性能优越的自动控制元件。为解决某型号雷达中磁粉离合器故障检测困难的问题,基于AT89C55WD设计了一种磁粉离合器智能检测系统,由检测控制仪和测试台组成,可对磁粉离合器进行跑合试验,以自动或手动方式测试磁粉离合器的性能。提高了修理机构对磁粉离合器进行修理的能力,具有显著的经济效益。     

Simplified model of an FSK-to-ASK direct-detection system using aFabry-Perot demodulator

Design guidelines are presented for a direct-detection optical transmission system in which an FSK (frequency-shift-keyed) signal is converted to ASK (amplitude-shift-keyed format) by a tunable Fabry-Perot filter demodulator/demultiplexer. The analysis gives an estimated set of conditions for the proper Fabry-Periot (FP) bandwidth and tone frequency deviation that reduces the system power penalities. This is accomplished by calculating the tonal power transmitted through the FP; this simplifying assumption neglects pattern dependences but provides a simple, useful expression for predicting regions of rapidly increasing power penalties. The generated curves agree well with experimental results for three different systems     

Analysis of an optical hybrid switch

This paper provides new loss models for an OCS/OBS optical hybrid switch. Exact results for the blocking probability based on an analysis, of a 3-dimension state-space Markov chain is derived when circuits are given preemptive priority over bursts and are allowed to wait a certain amount of time if all wavelengths are busy in the desired output link. Because it is difficult to-exactly compute the blocking probability in realistic scenarios, we derive a. computationally scalable approximation for the blocking probability reducing the 3-dimension state space into a single dimension.     

毫米波大规模MIMO系统基于等效信道的全连接混合预编码设计

为了提升毫米波大规模MIMO系统中基于全连接结构的混合预编码性能,提出一种基于等效信道两步设计法的混合预编码方案。首先结合发送端模拟预编码矩阵、接收端模拟组合矩阵和信道矩阵构造等效信道,以最大化等效信道增益为目标设计出收发端的模拟部分,之后对数字预编码矩阵与数字组合矩阵逐列应用最小二乘准则进行求解,设计出收发端数字部分。仿真结果表明,所提算法能够逼近最优全数字预编码方案且具有较低的复杂度,并具有较强的容错性。     

Adaptive type-II hybrid broadcast ARQ system

In this letter, a type-II hybrid broadcast automatic-repeat-request (ARQ) scheme with adaptive forward error correction (AFEC) using BCH codes is proposed and analyzed. The basic idea in the proposed scheme is to increase the error correcting capability of BCH codes according to each channel state using incremental redundancy. The numerical results for the analysis and the simulation show that the proposed scheme maintains high throughput even if channels become noisy and the number of receivers is large