远程考试中几个安全问题的探讨

基于Internet的远程考试系统带来了一系列的安全问题．就远程考试中的认证、加密、试卷保护及防作弊等问题，展开了较详细的讨论，并给出了相应的解决方案．     

远程考试中几个安全问题的探讨

基于Internet的远程考试系统带来了一系列的安全问题 .就远程考试中的认证、加密、试卷保护及防作弊等问题 ,展开了较详细的讨论 ,并给出了相应的解决方案     

网上考试系统安全性的探讨及解决方案

网上考试系统在各校已经广泛使用，它在一定程度上减轻了教师的工作量，提高了工作效率，本文对网上考试各环节可能涉及的安全问题作了较全面介绍，并提出了一定的解决办法。     

基于Web的计算机考试系统设计与实现

文章介绍了一种基于Web方式的计算机上机考试系统,由考试前端、题库管理和阅卷存档子系统等部分组成,主观性试题与客观性试题可以灵活组合.并详细介绍了系统的功能结构、抽题模型、安全机制及存档试卷生成技术.     

驾驶证科目考试流程管理系统设计

目前,全国机动车和驾驶人的保有量日益增加,道路交通安全问题日益突出。严格执行考试标准,强化考试过程监督,确保机动车驾驶人培训考试质量成为车管工作的重中之重。本文拟在规范考试工作流程、解决资料流转复杂且存在安全隐患、加强考试过程监控等方面进行探讨和实践。     

通用在线考试系统设计研究

学生成绩的测评是教学工作中的一个重要环节。传统考试存在效率低、周期长、对学生考试情况的反馈较弱等弊端。通用在线考试系统适应了教育信息化的要求，解决了传统考试的弊端，使考试管理更加的科学化和规范化。本文介绍了通用在线考试系统的设计目标和运行模式，详细分析了系统的功能架构，然后着重对数据库设计和组卷算法以及系统的安全设计进行了阐述，特别针对WEB服务器和数据库服务器的安全进行了设计。     

Internet网上考试系统安全体系的设计与实现

Internet网上考试系统以其开放性、交互性的突出优点在远程教育中得到充分的体现,但由于网络环境的不安全因素以及系统本身信息敏感性的特点,至使网上考试系统缺乏系统化的安全保障。本文针对网上考试系统所面临的安全威胁,提出了具体的设计方案与实现措施。     

网络考试系统的安全设计

从对数据库系统的安全分析入手，结合网络考试系统的实际，从硬件系统、数据库系统、网络操作系统和网络应用程序几个方面，提出了解决网络考试系统安全性的方法。     

新冠疫情防控下的特种作业考试安全管理

特种作业考试的安全管理直接关系考生、考务人员和设备设施的安全.在新冠疫情防控形势下,本文分析了特种作业考试的安全管理现状和考试风险,提出落实政府部门对疫情防控的要求,考试机构调整考试方式,考试点落实疫情防控措施,紧抓考试的安全管理,考务人员做好自身健康管理等措施,旨在为新冠防疫期间特种作业考试管理提供借鉴.     

基于Web的在线考试系统

提出了基于web的在线考试系统的解决方案，介绍了在线考试系统的功能、系统设计以及人机交互的实现，讨论了在线考试系统的实现策略、对系统文件及数据库的保护、系统的安全性等。     

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.     

A computer generator for randomly layered structures

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

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.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

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。     

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     

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     

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

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).