考试系统中操作题自动评分的设计与实现

目前的计算机考试系统大多数是采用标准答案文档与考生文档直接比对的方式来实现操作题的自动阅卷,评分效率不高,成绩容易出现误差。针对这一现象,以Word2003操作题为例,提出了改进的思路及具体的实现方法,即基于VBA技术和word对象模型,采用将标准答案存储到数据库中的方式,利用设置好的标准答案数据库,启动自动评分系统对操作题进行自动评分。实验结果表明,采用此方法设计的评分系统,平均30s左右就可以实现一个文档的自动评分,显著提高了操作题的评分效率。     

Coherent optical fibre delay-line processor

The operation of an optical fibre tapped delay line with a long coherence length source is described. Optical phase is retained; thus the system can perform bipolar (or in general complex-valued) signal processing operations. Experimental results are presented that illustrate the operating characteristics and capabilities of the system for simple time-domain processing operations.     

On-Line System Availability and Service Simulation (OLSASS)

A methodology for establishing a generalized Monte Carlo model for system availability and service simulation is useful to perform on-line tradeoff analyses. An example of an on-line time-shared computer program for a model of an infrequently operating system covering a large number of operational applications is described in detail. Examples of implementing the model for a variety of situations are also included. Advantages of this program are the ready accessibility to the engineer of a variety of field support operation simulations and their resultant availabilities and logistics requirements. Through tradeoff of system design parameters and operational variables, the simulation provides the capability for rapid system optimization at low computer cost.     

Semiconductor laser optical amplifiers for use in future fibersystems

The application of semiconductor laser amplifiers to long-wavelength optical fiber systems is discussed. The basic equations defining laser amplifier characteristics are presented together with experimental results. Linear and nonlinear modes of operation are considered; the former includes use as an optical gain block, a linear repeater, and a preamplifier, while the latter includes use as a bistable element, an electrically controlled optical switch, and an injection-locked amplifier     

Transfer characteristics of Brillouin fibre amplifiers for use in self-homodyne coherent optical transmission systems

Presents for the first time, the basic input-output characteristics of a Brillouin fibre amplifier, and shows that these are in good agreement with the first experimental results reported recently by other workers on a novel and potentially very important application of Brillouin amplification in a coherent optical fibre transmission system. For this type of application, theoretical results are also presented on the optical pump power dependence of the amplifier gain per unit optical pump power.<>     

一种可灵活接入的交叉连接系统

介绍一种可用于光纤接入网的交叉连接系统 (L XM)的基本设计思想。该系统可在用户和交换系统之间灵活接入 ,实现交叉连接功能 ,为光纤接入网提供可靠的窄带业务平台。     

Opto-electronic neuron-type operation via stimulated Ramanscattering in optical fiber

Neuron-type operation can be performed by an optoelectronic system that uses stimulated Raman scattering (SRS) for the weighted summation required in a neuron. The threshold of individual neurons can be controlled by varying the power and/or wavelength of a locally generated optical wave. We show that it is possible to perform negative weighting optically, in addition to the usual positive weighting. Negative weighting is possible due to the nature of SRS and is accomplished by using signaling at a different wavelength. Intensity weighting for the incoming signals is considered in this paper. Simulation results are obtained by considering SRS in optical fiber. However, the process is general and should be applicable in other materials     

基于模糊综合评判的智能光网络考核模型的研究

为了能对学员在智能光网络网管操作学习过程中的掌握程度作出客观的评价,根据操作型考核评判的特点,对考核模型进行了分析与实现,提出了结合模糊评判与分层评价的综合评判模型。分析了网管操作评价的指标体系、各指标权值的选取,运用综合评判方法完成了对受训学员操作能力的有效评估,并且结合模糊运算给出了学员考核的具体分数值。最后,利用学员操作过程中产生的数据进行分析处理,对学员的考核评价结果进行验证。结果证明,本评判模型能对受训学员做出客观的评价。     

基于高时空分辨率卫星数据的气溶胶光学厚度反演系统

卫星遥感技术是研究大气气溶胶时空变化规律的重要手段之一。高分四号卫星(GF-4)作为新一代静止卫星,不仅具备更多的可见-近红外波段,而且具有超高时空分辨率的特点,可以执行对固定区域连续观测或凝视扫描覆盖观测,为气溶胶光学厚度定量反演提供了有利条件。基于GF-4静止卫星超高时空分辨率卫星数据,在深入了解卫星观测模式及传感器波段对气溶胶反演敏感性基础上,基于地气时变差异核心思路,开发了针对GF-4超高时空分辨率数据气溶胶光学厚度反演算法;设计并实现了具备业务化反演气溶胶光学厚度能力的软件系统,软件系统具备多线程、全自动运行能力,满足卫星数据处理业务化需求。利用该系统对GF-4数据进行了处理和分析,通过地基仪器实测的气溶胶光学厚度进行了验证,取得了初步结果。结果表明,该系统具有良好的可靠性和稳定性,可以服务于大气颗粒物时空变化遥感监测。     

Link-16应用于空中打击“时间敏感目标”

分析美军空中作战通用信息需求,以空中打击地面“时间敏感目标(TST)”为例,梳理作战流程和基本信息需求,结合Link-16系统消息家族,研究空中打击地面TST作战各阶段的信息应用流程,给出了从作战应用—信息需求—消息流程的总体设计流程,为信息系统作战信息应用研究提供借鉴。     

最小可分辨对比度在机载电视系统中的应用研究

以最小可分辨对比度(MRC)理论为基础,研究MRC在机载CCD电视系统中的应用.讨论了影响MRC基本因素及计算模型,结合工程应用给出通过MRC进行作用距离预测的技术途径,介绍关键数据的确定方法和应用结果,避免用MTF、分辨率评价CCD成像系统的局限性,实现了在地面对产品作用距离的预测,建立了一种机载CCD电视系统科学实...     

陆战场红外侦察告警装备作战效能评估

为有效提高红外侦察告警装备作战运用水平,重点研究了陆战场(车载式)红外侦察告警装备的作战效能评估问题。首先分析了红外侦察告警装备工作原理和建立武器装备作战效能体系评估基本原则,建立了以探测能力、捕获能力、跟踪能力为主的两层指标体系;然后综合运用层次分析法、专家咨询法、模糊数学等理论,提出了一种适用的红外侦察告警装备作战效能评估方法,在构建样本矩阵和确定权重系数的基础上建立了评估数学模型;最后,通过实例计算验证了该方法的有效性。计算结果表明,该方法可用于陆军红外侦察告警装备设计的指标论证,也可以用于考核实际装备的作战效能。     

综合航电系统高速光纤数据总线应用研究

光纤通信技术在军用航空领域具有广阔的应用前景.国外发达国家在机载综合航电系统高速光纤数据总线研究、应用方面已取得了突破性进展.分析了机载综合航电系统高速光纤数据总线的应用特点和研究、应用现状.     

基于单片机控制的简易数字程控交换系统

介绍了一种基于单片机控制的简易程控时分交换系统，它能模仿市话的一些基本功能，对该系统的工作原理、硬件与软件设计分别进行了详细的论述。     

Hierarchy Bayesian model based services awareness of high-speed optical access networks

As the speed of optical access networks soars with ever increasing multiple services, the service-supporting ability of optical access networks suffers greatly from the shortage of service awareness. Aiming to solve this problem, a hierarchy Bayesian model based services awareness mechanism is proposed for high-speed optical access networks. This approach builds a so-called hierarchy Bayesian model, according to the structure of typical optical access networks. Moreover, the proposed scheme is able to conduct simple services awareness operation in each optical network unit (ONU) and to perform complex services awareness from the whole view of system in optical line terminal (OLT). Simulation results show that the proposed scheme is able to achieve better quality of services (QoS), in terms of packet loss rate and time delay.     

全雪崩晶体管驱动器选脉冲开关

研制出一种全雪崩晶体管驱动器光开关装置,它用于从锁模脉冲系列中可靠地选出一个单脉冲。本文阐述了它的工作原理和研制结果。测试结果表明,该装置具有性能稳定、工作可靠、延迟时间短(～20毫微秒)、抖动小、寿命长和无电磁干扰等优点。     

光纤传感器的发展及应用

本文首先本文对光纤传感器技术的发展进行了概述,介绍了与光纤相关的基础理论,随后介绍了光纤传感器的组成与分类.就光纤传感器的应用方面进行了分析与说明,指出光纤传感器用途十分广泛,在土木工程,生物医学,电力系统中发挥着巨大的作用.最后,本文展望了光纤传感器技术的发展趋势与前景.     

智能光纤监测技术在电力光通信中的应用

智能光纤监测技术(eODN)是光纤通信先进的网络运维技术.首先进行了智能电网光纤网络运维分析,然后从eODN基本原理、应用可行性、故障处理建议、市场应用方面分析了eODN技术在智能电网光通信中的应用可行性.eODN可实现电力光纤网络的智能化管理,提升电力光纤通信的可靠性和网络维护的便捷性.     

一种资源视角的关系特性分析与建模方法

为满足联合作战条件下信息系统对资源数据灵活组合应用的需求,从作战资源视角出发,聚焦资源的关系特征维度,开展了资源与资源、资源与功能的关系特性分析,确定了各类关系的概念内涵、基本属性及关系特征要素集的组成,同时研究了资源视角关系特征的表征方法,并针对资源能力溯源及资源能力认知等展开了关系特征模型应用分析。通过资源视角关系特性分析与建模,可提高信息系统对资源的快速组织和应用能力,为从事军事资源联合运筹与信息系统研制提供参考。