面向接口编程在Java中的典型应用

接口是一个业务逻辑,面向接口编程就是把客户的业务提取出来,定义成接口（inter-face）。业务具体实现通过该接口的实现类来完成,若业务需求变化,只需编写该业务逻辑的新的实现类,不需要改写现有代码,减少对系统的影响。这种主体构架使用接口,接口构成系统的骨架的编程方式,大大增强了代码的可扩展性（可伸缩性）和可维护性。     

C＋＋的this指针和C#的this引用

this在C＋＋中称为this指针，它代表了当前实例的内存地址；在C#中称为this引用：使用this可以在类中方便地访问到本类的当前实例，也可以将本类的当前实例方便地传送到另一个类中去。通过多个例子，说明了在C＋＋和C#中显示或隐含使用this的方法．这些方法是编辑中的常用技巧．     

基于数据中心平台的数据整合研究

针对目前高校数字化校园出现的＂信息孤岛＂问题,提出了一种基于数据中心平台的数据整合的方案,建立了数据中心平台,实现了统一身份认证。通过使用共享数据库,保证全局数据的共享,实现了对异构数据库的查询和联合使用;通过采用基于ICE（Ineternet Communication Engine）认证接口的统一身份认证,为用户提供数字校园的单一入口,实现用户的单点登录。     

协调Powerbulider与Oracle提高应用系统性能

一、使用ＰＢ与Ｏｒａｃｌｅ专用接口ＰＢ与数据库服务器的接口分为两类：一类与某数据库的专用接口（如ＰＢ到Ｏｒａｃｌｅ）,另一类为ＯＤＢＣ接口。由于ＰＢ到Ｏｒａｃｌｅ的专用接口比ＯＤＢＣ接口快得多,因此在应用系统中应使用ＰＢ与Ｏｒａｃｌｅ的专用接口,其具体使用方法如下：１．ＰＢ５与Ｏｒａｃｌｅ的专用接口若使用ＰＢ为５．０～５．０２版本,Ｏｒａｃｌｅ为７．１或７２,则在安装ＰＢ时选用定制安装,并根据Ｏｒａｃｌｅ版本选择专用接口Ｏｒａｃｌｅ７．１或Ｏｒａｃｌｅ７．２,安装完毕后,再将Ｏｒａｃｌｅ客户端安…     

VISUAL C＋＋5.0中ODBC编程技巧

ODBCProgrammingSkillsinVisualC++5.0ZhangXiaoyuHuangShaobinHuangBinODBC（OpenDatabaseConnechvity开放式数据库连接）是一种用来在相关或不相关的数据库管理系统（DBMS）中存取数据的标准应用程序接口（API）。它是一种使用SQL的程序设计接口,允许应用直接访问任何数据库中的数据,并且已经得到了大多数DBMS厂商们的支持。ODBC大体上提供两种驱动程序：一种驱动程序使用与数据库管理器相同的语言;另一种驱动程序为程序语言提供了公用接口。两种驱动程序以公共接口为交汇点,此公共接口允许VisualC＋＋使用一整套的…     

光驱故障的分类及实例分析

CD－BOM驱动器,又称先驱,是微机系统中重要的只读外存设备,由机械部件、电子部件和光学部件三类部件组成。随着软件光盘化日益成为潮流,CD－ROM驱动器的使用率大大提高。但在使用、维护时较普通软盘、硬盘复杂,且故障率较高,故障的分析、定位也较复杂。光驱的故障按故障源分为以下六类。1接回故障此类故障主要原因有：CD－BOM驱动器的接口与主板接口不匹配（出现CDR－103错误提示）,在增加或减少新硬件时,造成CD－ROM驱动器的信号线（包括与其它多媒体部件的连接线）、电源线、跳线等之间的松动、错误连接或断线等等。这…     

改进的Java类文件保护方法

编译后的Java类文件很容易被反编译,在Java应用上会产生源代码的安全问题。该文对传统的Java类文件保护方法进行分析,在类加载器（ClassLoader）加密技术的基础上,提出一种使用JNI技术调用本地解密接13的改进方法。解密接口在设计上保证了JNI技术调用本地解密接口时的通信安全,从而提升了Java类文件的安全性。实验结果表明,该方法是有效的。     

本来就很“熟”——图解笔记本外部接口

各位“本本”用户在使用笔记本电脑的时候，可曾注意到周围那些大大小小的接口？虽然我们每天面对笔记本，或工作或娱乐，对于这些接口自然也很熟悉，但是除了对少数经常使用的接口略知一二外，那些不常用的接口我们就大多不知道是干什么用的了。实际上这些接口各自有自己不同的功能，用户应该掌握这些接口，让其发挥功能。下面我们就来为大家介绍这些看似熟悉的笔记本外部接口吧!     

如何规避网上支付的安全风险？

攻击者通常用哪些手段得到支付密码呢？（1）骗取手段。攻击者可以采用＂钓鱼＂方式达到目的。具体方式有假冒网站、虚假短信（邮件）。这些网站页面、短信或邮件是他们的＂诱饵＂。不能识别这些诈骗手段的持卡人容易被攻击者诱骗,乖乖地向其泄漏自己的银行卡支付密码。（2）支付终端截取。攻击者可以在持卡人电脑上发布恶意软件（如木马软件）。     

基于J2ME的手机软件开发(三)

简要介绍了MIDP中多线程（Thread类、Runnable接口）以及定时器的使用,并分别给出了利用两种技术编写的无线购物用户登录界面实例和时钟屏幕保护实例。     

“个性成才”理念在《动态网页设计》中的应用

采用先进的教育教学理念,结合自身的教育教学实践,提出在《动态网页设计》课程中运用"个性成才"的理念进行教学,目的是了解每位学生的个性,因势利导,使每位学生都能充分发挥其个性特长。     

一种新的基于目标和特征的图像分类框架

首先提出了一种图像分类的结构。根据子块技术和形状描述技术来获取图像中的目标,如果图像类属于目标图像类,则提取图像中目标图像的特征,否则提取整幅图像的底层特征。然后利用主分量分析方法（PCA）对提取的特征进行降维处理,降维处理后的数据由支持向量机进行分类。该方法在标准的Corel图像库上进行了测试,实验结果表明提出的方法有效地提高了图像分类的性能,图像分类的结果与图像的高层语义概念相一致。     

Practical reliable Bayesian recognition of 2D and 3D objects usingimplicit polynomials and algebraic invariants

We treat the use of more complex higher degree polynomial curves and surfaces of degree higher than 2, which have many desirable properties for object recognition and position estimation, and attack the instability problem arising in their use with partial and noisy data. The scenario discussed in this paper is one where we have a set of objects that are modeled as implicit polynomial functions, or a set of representations of classes of objects with each object in a class modeled as an implicit polynomial function, stored in the database. Then, given partial data from one of the objects, we want to recognize the object (or the object class) or collect more data in order to get better parameter estimates for more reliable recognition. Two problems arising in this scenario are discussed: 1) the problem of recognizing these polynomials by comparing them in terms of their coefficients; and 2) the problem of where to collect data so as to improve the parameter estimates as quickly as possible. We use an asymptotic Bayesian approximation for solving the two problems. The intrinsic dimensionality of polynomials and the use of the Mahalanobis distance are discussed     

Classes of Spatio-Temporal Objects and their Closure Properties

We present a data model for spatio-temporal databases. In this model spatio-temporal data is represented as a finite union of objects described by means of a spatial reference object, a temporal object and a geometric transformation function that determines the change or movement of the reference object in time.We define a number of practically relevant classes of spatio-temporal objects, and give complete results concerning closure under Boolean set operators for these classes. Since only few classes are closed under all set operators, we suggest an extension of the model, which leads to better closure properties, and therefore increased practical applicability. We also discuss a normal form for this extended data model.     

On the ternary spatial relation "between".

The spatial relation "between" is a notion which is intrinsically both fuzzy and contextual, and depends, in particular, on the shape of the objects. The literature is quite poor on this and the few existing definitions do not take into account these aspects. In particular, an object B that is in a concavity of an object A1 not visible from an object A2 is considered between A1 and A2 for most definitions, which is counter intuitive. Also, none of the definitions deal with cases where one object is much more elongated than the other. Here, we propose definitions which are based on convexity, morphological operators, and separation tools, and a fuzzy notion of visibility. They correspond to the main intuitive exceptions of the relation. We distinguish between cases where objects have similar spatial extensions and cases where one object is much more extended than the other. Extensions to cases where objects, themselves, are fuzzy and to three-dimensional space are proposed as well. The original work proposed in this paper covers the main classes of situations and overcomes the limits of existing approaches, particularly concerning nonvisible concavities and extended objects. Moreover, the definitions capture the intrinsic imprecision attached to this relation. The main proposed definitions are illustrated on real data from medical images.     

From Aardvark to Zorro: A Benchmark for Mammal Image Classification

Current object recognition systems aim at recognizing numerous object classes under limited supervision conditions. This paper provides a benchmark for evaluating progress on this fundamental task. Several methods have recently proposed to utilize the commonalities between object classes in order to improve generalization accuracy. Such methods can be termed interclass transfer techniques. However, it is currently difficult to asses which of the proposed methods maximally utilizes the shared structure of related classes. In order to facilitate the development, as well as the assessment of methods for dealing with multiple related classes, a new dataset including images of several hundred mammal classes, is provided, together with preliminary results of its use. The images in this dataset are organized into five levels of variability, and their labels include information on the objects’ identity, location and pose. From this dataset, a classification benchmark has been derived, requiring fine distinctions between 72 mammal classes. It is then demonstrated that a recognition method which is highly successful on the Caltech101, attains limited accuracy on the current benchmark (36.5%). Since this method does not utilize the shared structure between classes, the question remains as to whether interclass transfer methods can increase the accuracy to the level of human performance (90%). We suggest that a labeled benchmark of the type provided, containing a large number of related classes is crucial for the development and evaluation of classification methods which make efficient use of interclass transfer.     

一种运动目标检测优化算法

提出了一种用于图像序列中检测运动目标的优化算法。针对用于室内目标检测的差分法存在着“虚影”噪声,以及用于室外目标检测的背景估计法在对短序列进行检测时,其结果中存在“残像”噪声的问题,揭示并利用两次差分之间的相关性实现了对“虚影”的检测并将其消除,将其引入背景估计法,以消除后者存在的“残像”噪声。实验表明,该方法在目标检测中不仅消除了“虚影”和“残像”噪声,而且检测结果的完整性显著提高。     

Temporal association algebra: a mathematical foundation forprocessing object-oriented temporal databases

This paper describes an object-oriented temporal association algebra (called TA-algebra) which is intended to serve as a formal foundation for supporting a pattern-based query specification and processing paradigm. Different from the traditional table-and-attribute-based paradigm, the pattern-based paradigm views the intension of an object-oriented temporal database as a network of object classes interconnected by different association types and its extension as a network of associated temporal object instances. Consistent with this view, queries can be specified in terms of patterns of temporal object associations or nonassociations (i.e., linear, tree and network structures of object classes/objects with logical AND and OR branches). TA-algebra provides a set of algebraic operators for processing these patterns and allows the direct and/or indirect associations and/or nonassociations among temporal object instances to be more explicitly represented and maintained during processing than the traditional tabular representation of temporary or final query results. TA-algebra operators are based on time-interval and valid-time semantics and they preserve the closure property. The algebra is capable of operating on heterogeneous as well as homogeneous patterns of object associations. Both homogeneous and heterogeneous patterns are decomposed into a set of primitive temporal pattern instances for uniform treatment. This paper formally defines the TA-algebra operators and their mathematical properties. The applications of these operators in query decomposition and processing are illustrated by examples     

“数制及数据表示”以史为据教学法

本文提出理论知识的教学可分为"以理为据"和"以史为据"两大类;展示了按照类似历史的发展方式来讲授数制及数据表示的教学方法。通过虚拟的历史发展来讲解权重,不需要使用复杂的数学推理,就能启发学生直观地理解数制转换方法。