基于Web的考试系统组卷策略研究

运用多种策略相结合的组卷方式,针对互联网中用户需求多样性的特点,从提高组卷效率出发,智能地生成不同的试卷或者习题以满足互联网用户的不同需求．     

基于自适应遗传算法的自动组卷策略研究

随着计算机辅助教学和网络的迅速发展,在线考试将逐步替代传统的考试方式而被广泛应用.利用计算机完成自动组卷也将替代原有的人工出卷方式,成为在线考试系统的核心功能之一.本文在量化组卷需求的基础上,提出了一种基于遗传算法的自动组卷策略,将试卷抽象为染色体,每道题抽象为染色体中的一个基因,不断抽取出相应的试题组成多份试卷,最终根据用户设置的组卷参数,选择与用户期望值最接近的一份试卷,本文选取试题号作为单个基因编号对染色体进行编码,避免了解码和多余空间搜索的时间消耗,实验表明基于遗传算法的自动组卷结果较符合出卷要求.     

卫星图像分割的聚类算法

组卷问题是一个在一定约束条件下的多目标参数优化问题,而它的约束条件难以用数学形式描述,所以采用传统的数学方法求解十分困难。实践证明,用遗传算法求解组卷问题有较好的效果。本文中提出的改进的遗传算法,采用功能块结构,可以在初始种群时满足试卷的部分约束(题型、题数、题分),并无须在进化过程中对这些约束进行控制,降低了问题的难度,提高了问题求解的效率。而且在保证整个试卷的分数不变的前提下,适当地增大误差,可以大幅度减少组卷时间,尤其适用于网络环境下用户对组卷速度要求较高的考试情况。     

基于智能出卷系统的自适应难度调节

随着计算机网络技术的迅猛发展,构建在计算机网络环境上的出卷系统也被越来越多的单位和部门所使用.考试从传统的纸质试卷作业变成计算机作业已经成为不可抗拒的潮流.在智能出卷系统中,有一个重要的参数就是难度系数.难度系数的准确性关系到整个试卷出题难度的准确性.本文提出了一种对试题出卷系统中的难度系数的自适应调节方法.利用统计规律和人工经验相结合的方式对题目的难度系数进行调节,使得出卷系统能够生成不同难度级别的试卷,以满足不同用户的需求.     

基于.NET的《WEB程序设计》网络课件设计与实现

在分析网络教学课件功能和体系架构的基础上,基于.NET平台和SQL SERVER2005数据库设计开发《WEB程序设计》课程网络教学课件。该课程网络教学课件系统,教学资源丰富,资料更新便利,交互性强,能更好地激发学生自主学习;并且,课件系统还创造性的引入工作流管理技术,具备一定的智能性,可以实现智能组卷和在线考试,在学生作业过程中,教师还可以全程在线参与,实现作业过程的控制和管理,提高学生的实训效率和教学质量。     

在线考试组卷算法研究

针对网络化教学的需求，文中提出了一个在线考试系统，为了使生成的试卷更客观、科学、和有区分度，文中首先讨论了组卷原则，并围绕这组组卷原则，提出了一个结构合理的试题库和自动组卷算法，提出了一套合理的组卷参数，从而实现了一个自动化试卷生成及考试系统。该系统已嵌入到学校的网络教学系统中，运行良好。     

ADO.NET和SQL Server在智能题库系统实现中的应用

智能题库系统是基于网络用户对试卷的要求进行组卷,并自动生成试卷,系统通过对数据库的不断更 新,实现对题库的管理．本文着重阐述ADO．NET和SQL Server在智能题库系统中的应用．     

自动组卷考试系统的设计与实现

利用计算机实施自动组卷的目标是输出符合用户需求的最佳试卷。组卷问题实质是一个约束条件自动求解问题。遗传算法是一种优秀的全局优化算法,它具有全局搜索、编码方式灵活等特点,对于解决此类问题非常方便。     

基于Java的教学试卷设计辅助系统

针对实际教学工作中需要的教学试卷设计辅助系统给出了较为完整的解决方案.系统采用Java工具和My SQL数据库开发,实现了用户快捷手工组卷和电子组卷,提高了工作效率.     

一种可调整式的多元变量渐近寻优组卷策略

论述了基于智能组卷策略的题库系统设计的意义,分析了目前已有智能组卷策略存在的问题,针对目前智能组卷策略存在的组卷效率低,灵活性差的问题,提出了一种新的智能组卷策略.新策略采用条形码标识试题,按照对试卷整体约束条件影响的大小依次选取控制参数,优化了搜索路径,提高了智能组卷的效率,增强了智能组卷的灵活性.对不同题库系统进行了软件测试,并对软件测试结果进行了简要的分析,实际运行结果表明,新策略优化了搜索过程、减少了时间开销、提高了组卷的成功率.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with