新版百元币防伪特征与光学鉴别

本文从纸张、油墨、印刷等方面介绍了新版百元币的票面特征、设计特点,并运用配光、显微照相、特种照相等检验手段分析了该币的防伪特征,为鉴别真伪提供了科学依据。     

用基于叠层元的h－p方式自适应有限元计算磁场问题（I）

对于磁场问题的自适应有限元计算，许多作者采用ｈ加密方式，近几年来，也有一些作者采用ｐ加密方式；关于ｈ－Ｐ加密方式，虽然在理论上早已肯定，却一直未在实际上真正实施。本文在作者关于叠层三角元结构的理论分析基础上，提出两种磁场有限元计算的简便易行且达到较高精度的ｈ－Ｐ方式自适应方案；并对几个具有解析解的典型问题，从精度和ＣＰＵ时间等方面对ｈ－Ｐ方式和ｈ方式进行了全面的比较。     

A New Storage Strategy for Hypertext Based Version Control

ＡＮｅｗＳｔｏｒａｇｅＳｔｒａｔｅｇｙｆｏｒＨｙｐｅｒｔｅｘｔＢａｓｅｄＶｅｒｓｉｏｎＣｏｎｔｒｏｌＷＡＮＧＹａｎ；ＧＵＯＦｕｓｈｕｎ；ＬＩＬｉａｎｚｈｉ；ＷＥＩＬｉｎｇ（王岩）（郭福顺）（李莲治）（魏玲）（Ｄｅｐｔ．ｏｆＣｏｍｐｕｔｅｒＳｃｉｅｎｃ...     

论文学翻译中译者的创造性叛逆——以《红楼梦》库恩德译本为例

谈到文学翻译,人们会立即想到＂翻译者,叛逆也＂这一说法。由于中西方语言体系之间存在极大的差异,而文学翻译的目的是进行文化传播与信息交流,所以在文学翻译过程中,译者势必会发挥主观创造性,甚至是叛逆性,对原著进行变通。译者的＂创造性叛逆＂在文学翻译作品中普遍存在,对于各民族文化交流而言具有重大的意义。结合《红楼梦》库恩德译本对＂创造性叛逆＂这一文化现象进行分析,探讨其内涵意义以及表现形式。     

共聚焦点（CFP）成像技术述评

CFP成像有共聚焦和双聚焦两种形式。前者用于寻找构造信息，后者则主要用于分析与储层描述有关的信息。借助于两个连续且相互独立的聚焦步骤，CFP成像技术将叠前偏移与速度分析分离开来，用算子更新代替传统的对速度场直接更新，最后由经正确更新的聚焦算子反演出地下速度场。该技术在精确成像的同时，很好地避免了速度难题。这一优良特性可被广泛应用于地震数据反演和处理的各个方面（处理复杂近地表难题、多次波消除、多分量偏移、地下盐丘成像及时延地震监测等）。因此，CFP成像技术是一种理论上先进、应用前景广阔的新的成像技术，对复杂地质问题的解决更是有着独到的功效，在我国可望有广阔的发展空间。     

A numerical approach for planning offshore wind farms from regional to local scales over the Mediterranean

Renewable energy resources, such as wind, are available worldwide. Locating areas with high and continual wind sources are crucial in pre-planning of wind farms. Vast offshore areas are characterized by higher and more reliable wind resources in comparison with continental areas. However, offshore wind energy production is in a quite preliminary phase. Elaborating the potential productivity of wind farms over such areas is challenging due to sparse in situ observations. The Mediterranean basin is not an exception. In this study we are proposing numerical simulations of near-surface wind fields from regional climate models (RCMs) in order to obtain and fill the gaps in observations over the Mediterranean basin. Four simulations produced with two regional climate models are examined here. Remote sensing observations (QuikSCAT satellite) are used to assess the skill of the simulated fields. A technique for estimating the potential energy from the wind fields over the region is introduced. The wind energy potential atlas and the map of a wind turbine's functional range are presented, locating the potentially interesting sub-regions for wind farms. The ability of models to reproduce the annual cycle and the probability density function of wind speed anomalies are detailed for specified sub-regions.     

基于B+树的动态数据持有性证明方案

针对云存储环境下的数据持有性证明（PDP）方案效率较低、不能很好支持全动态更新的问题,设计了一种基于B⁺树的动态数据持有性证明方案。该方案引入双线性对技术和数据版本表,支持用户进行数据块级的细粒度动态操作并能保护用户的数据隐私。通过优化系统模型并设计节点索引值,使第三方检测机构能识别错误数据并进行精确定位。理论分析及实验结果表明,与基于Merkel哈希树（MHT）的方案相比,所提方案能够显著降低系统构造认证数据结构的时间开销,并且简化了动态更新过程,提高了第三方检测机构的验证效率。     

Efficient Specialization of Relational Concepts

An algorithm is presented for a common induction problem, the specialization of overty general concepts. A concept is too general when it matches a negative example. The particular case addressed here assumes that concepts are represented as conjunctions of positive literals, that specialization is performed by conjoining literals to the overly general concept, and that the resulting specializations are to be as general as possible. Although the problem is NP-hard, there exists an algorithm, based on manipulation of bit vectors, that has provided good performance in practice.     

Learning Conjunctive Concepts in Structural Domains

We study the problem of learning conjunctive concepts from examples on structural domains like the blocks world. This class of concepts is formally defined, and it is shown that even for samples in which each example (positive or negative) is a two-object scene, it is NP-complete to determine if there is any concept in this class that is consistent with the sample. We demonstrate how this result affects the feasibility of Mitchell's version of space approach and how it shows that it is unlikely that this class of concepts is polynomially learnable from random examples alone in the PAC framework of Valiant. On the other hand, we show that for any fixed bound on the number of objects per scene, this class is polynomially learnable if, in addition to providing random examples, we allow the learning algorithm to make subset queries. In establishing this result, we calculate the capacity of the hypothesis space of conjunctive concepts in a structural domain and use a general theorem of Vapnik and Chervonenkis. This latter result can also be used to estimate a sample size sufficient for heuristic learning techniques that do not use queries.     

ArcSDE版本机制实现水土流失时空数据库

为实现水土流失数据库由常用的空间数据库向时空数据库的转变,并为解决水土流失“长事务”业务与常用“锁定—修改—释放”的事务处理策略间的矛盾,提出了用ArcSDE版本机制实现水土流失时空数据库的方法。针对几种有代表性的时空数据模型的特点和其局限性,提出了基于ArcSDE版本机制的时空数据模型,阐述了ArcSDE版本机制实现水土流失时空数据库的方法,介绍了用ArcEngine实现历史回溯和版本合并的具体方法。应用结果表明,该方法解决了水土流失监测业务中长事务问题。