JAC: an aspect‐based distributed dynamic framework

In this paper, we present the Java Aspect Components (JAC) framework for building aspect‐oriented distributed applications in Java. This paper describes the aspect‐oriented programming model and the architectural details of the framework implementation. The framework enables extension of application semantics for handling well‐separated concerns. This is achieved with a software entity called an aspect component (AC). ACs provide distributed pointcuts, dynamic wrappers and metamodel annotations. Distributed pointcuts are a key feature of our framework. They enable the definition of crosscutting structures that do not need to be located on a single host. ACs are dynamic. They can be added, removed, and controlled at runtime. This enables our framework to be used in highly dynamic environments where adaptable software is needed. Copyright © 2004 John Wiley & Sons, Ltd.     

从面向方面程序设计的定义到面向方面程序设计语言

目前无论在学术界还是工业界,很多人士简单地将面向方面程序设计理解为模块化横切关注点,狭隘地认为 面向方面程序设计构建在面向对象程序设计之上,是面向对象程序设计的扩展、有效的补充等。回顾了面向方面程序 设计的定义,分析了面向方面程序设计区别于其它程序设计方法的本质特征,并形式化了定义中的量化语句与方面, 给出了量化语句与方面的语义。重申了面向方面程序设计的本质特性是Quantification与()bliviousncss,模块化横切 关注点只是其带来的一个好处。同时指出了面向方面程序设计是一种新型的程序设计范式,独立于面向对象等其它 程序设计方法。并且,基于此定义,给出了面向方面程序设计语言需满足的最小条件集,并比较了主流的面向方面程 序设计语言,探讨了这些语言在面向方面程序设计理念上的差异。     

Hough变换的新定义

本文的主要工作有以下三个方面：首先通过多方面分析，指出文献中Ｈｏｕｇｈ变换的模板匹配式定义是不完善的；其次我们发现Ｈｏｕｇｈ变换具有一种固有的概率特征，它和待处理的图像无关，但对Ｈｏｕｇｈ变换的性能有根本性的影响，为了描述这种概率特征，本文提出了曲线（曲面）密度函数的概念；最后基于上述两方面的分析，本文给出了Ｈｏｕｇｈ变换的一种新定义。     

基于RBAC的扩展访问控制模型

权限管理是信息系统的重要环节,一个好的权限管理系统是成功的信息系统的重要因素。基于角色的权限控制策略提供了较高的灵活性和较低的管理负担,是目前研究的重点,文章在经典的基于角色的访问控制模型(RBAC)和基于任务的访问控制模型(TBAC)的基础上,对角色的管理和权限的定义进行了扩展,定义了更加灵活的基于角色的扩展权限控制模型XRBAC(Extended Role-Based Access Control)。     

图像清晰度评价方法研究

数字图像的清晰度评价一直是各类数字成像系统的一个关键问题，而在已有的一些的评价参数中，由于评价方法不同，均存在一些局限性，为此，针对图像的清晰程度提出一种新的评价方法，目的在于能够快速、准确地评价数字图像的清晰度。该评价方法评价参数可通过改进边缘锐度算法(EAV)得到，然后与机测MTF值的变化趋势一起做曲线回归分析，以便和其他传统清晰度评价参数做对比。通过上百幅各类数字图像的测试，结果表明，该评价参数与数字成像系统的MTF值变化有着很好的正相关关系，其不仅能够更准确地反应数字图像清晰度变化的趋势，而且便于简捷、快速地应用于各类数字图像的清晰度评价。     

恶意代码的机理与模型研究

恶意代码是信息系统安全的主要威胁之一.从操作系统体系结构的角度研究了恶意代码的产生根源,指出PC操作系统中存在特权主体、内核扩展机制不安全,程序执行环境保护不力等弱点是造成恶意代码泛滥的本质原因.基于F.Cohen的计算机病毒定义,对计算机病毒的传播机理进行了形式化描述.研究了蠕虫程序的模块结构.建立了数据驱动型软件攻击的理论模型,分析了其构成威胁的本质原因.     

浅谈信息设计

信息设计(information design)是一个迅速发展的学科,也是一个引人瞩目的新兴研究点。本文从信息设计的定义入手,然后从信息设计的用途、如何应用信息设计等角度展开分析研究。论文中举了大量的例子,希望能够帮助读者更好的理解。     

一种新的软件Agent设计的评价标准:用户自治性

本文提出了软件Ａｇｅｎｔ设计中的用户自治性标准,我们认为用户自治性是Ａｇｅｎｔ设计中需要考虑的重要方面,探讨了自治性标准在Ａｇｅｎｔ设计中的定义以及Ａｇｅｎｔ如何影响用户自治性,并在此基础上提出了一个新的软件系统模型。     

A New Definition of the Hough Transform

This paper‘s main contributions are three-fold.Firstly,it is shown that the two existing template matching-like definitions of the Hough transform in the literature are inadequate.Secondly,an inherent probabilistic aspect of the Hough transform embedded in the transformation process from image space to parameter space is clarified.Thirdly,a new definition of the Hough transform is proposed which takes into account both the intersection scheme between the mapping curve(or mapping surface) and accumulator cells and the inherent probabilistic characteristics.     

Challenges with high aspect ratio nanoimprint

When nanoimprint is not used for lithography purposes (NIL), but for the direct patterning of polymeric layers, high aspect ratio patterns may be of interest for a number of applications. The definition of such patterns in a nanoimprint process deals with two aspects, a successful filling of the high aspect ratio cavities of the stamp used, followed by a successful separation of the high aspect ratio structures defined in the polymeric layer on the substrate, from the stamp. These two aspects are addressed by shedding light to the impact of capillary effects during the filling of high aspect ratio cavities, and to the deformation processes involved in the separation of the stamp from the polymeric structures, where adhesional energies have to be overcome without cohesional failure. Both aspects are discussed in terms of the geometries involved, the stamp geometries as well as the polymeric layer thickness, and correlations with thermally-assisted (T-NIL) and UV-assisted (UV-NIL) processing are deduced. The aspects discussed are typical of a nanoimprint situation with thin polymeric layers on hard substrates.     

一种AOP方面的代数语义

面向方面程序设计可以模块化横切关注点,因此受到工业界及学术界的广泛关注。目前模块化横切关注点几乎成为面向方面程序设计的代名词,而且有不少人士狭隘地将面向方面程序设计认为是面向对象程序设计的延续、扩展或补充。回顾了面向方面程序设计的定义,分析了产生这一现象的原因。并且形式化了定义中的量化语句和方面,给出了它们的语义。探讨了量化语句和方面的一系列性质,包括量化语句和方面的可满足性,量化语句的包含、交叉及精化关系,方面的同态、同构、构成、完全语义保持精化、语义保持精化及等价替换等关系。该研究为面向方面程序设计的理论研究打下了坚实的基础,也为更好地理解面向方面程序设计提供了有效的帮助。     

Definition of standards-based building blocks for multimedia content management

The emergence of new ways of rendering multimedia content from a multiplicity of devices like tablets, smartphones, consoles or smart TVs, opens a complete set of new opportunities for multimedia services providers. It is important that the development of those disruptive services is done in an interoperable way. Existing service-oriented middleware platforms and recently developed standards devoted to the definition and implementation of complex multimedia services may speed up its development. In this context, the identification of different content management scenarios including the high-level functionalities they require is an important aspect to be able to implement services in a flexible and interoperable way. Use of standards and standards-based architectures will be a key aspect to combine services offered by different providers. In this paper, we propose the definition of standards-based building blocks based on the high-level functionalities required by content management and distribution scenarios. This will facilitate provision of complex new services specially focused, but not limited to, the management and distribution of multimedia content.     

Guided Structure-Aware Review Summarization

Although the goal of traditional text summarization is to generate summaries with diverse information,most of those applications have no explicit definition of the information structure.Thus,it is difficult to generate truly structureaware summaries because the information structure to guide summarization is unclear.In this paper,we present a novel framework to generate guided summaries for product reviews.The guided summary has an explicitly defined structure which comes from the important aspects of products.The proposed framework attempts to maximize expected aspect satisfaction during summary generation.The importance of an aspect to a generated summary is modeled using Labeled Latent Dirichlet Allocation.Empirical experimental results on consumer reviews of cars show the effectiveness of our method.     

On Algebraic Structure of L‐Fuzzy Bags

This study introduces a revised definition for fuzzy bags. It is based on the definition of bags given by Delgado et al. (Int J Intell Syst 2009;24:706–721) in which each bag has two parts: function and summary information. The new definition is given as a special case of L‐fuzzy bags, where L is a complete lattice. By some examples, the new concept is illustrated. Furthermore, the algebraic structure of L‐fuzzy bags is studied and the concept of α‐cuts, L‐fuzzy bag relations, and related theorems are given.     

网络化制造环境下一种面向能力的制造资源模型

制造资源管理是网络化制造中重要的一环。针对现有模型中共享资源在实现可行性方面存在的不足，提出建立一种面向能力的制造资源模型，并以XML格式进行描述。在此基础之上，建立了基于制造特征的任务定义模型。     

基于特征参数模型的对话框生成

本文介绍特征参数模型中的语义规定，使特征参数按预先设定受表达式、表格约束。系统可根据特征参数模型自动生成对话框，通过参数的调整可自动改变对话框显示外观。     

A taxonomy for key performance indicators management

In recent years, research on Key Performance Indicators (KPIs) management has grown exponentially, giving rise to a multitude of heterogeneous approaches addressing any aspect concerning it. In this paper, we plot the landscape of published works related with KPIs management, organizing and synthesizing them by means of a unified taxonomy that encompasses the aspects considered by other proposals, and it captures the overall characteristics of KPIs. Since most of the literature centers on the definition of KPIs, we mainly focus on such an aspect of KPIs management. Our work is intended to provide remarkable benefits such as enhancing the understanding of KPIs management, or helping users decide about the most suitable solution for their requirements.     

Characterizing computer input with Fitts’ law parameters—the information and non-information aspects of pointing

Throughput (TP), also known as index of performance or bandwidth in Fitts’ law tasks, has been a fundamental metric in quantifying input system performance. The operational definition of TP is varied in the literature. In part thanks to the common interpretations of International Standard ISO 9241-9, the “Ergonomic requirements for office work with visual display terminals—Part 9: Requirements for non-keyboard input devices”, the measurements of throughput have increasingly converged onto the average ratio of index of difficulty (ID) and trial completion time (MT), i.e. TP=ID/MT. In lieu of the complete Fitts’ law regression results that can only be represented by both slope (b) and intercept (a) (or MT=a+b ID), TP has been used as the sole performance characteristic of input devices, which is problematic. We show that TP defined as ID/MT is an ill-defined concept that may change its value with the set of ID values used for the same input device and cannot be generalized beyond specific experimental target distances and sizes. The greater the absolute value of a is, the more variable TP (=ID/MT) is. ID/MT only equals a constant 1/b when a=0. We suggest that future studies should use the complete Fitts’ law regression characterized by (a, b) parameters to characterize an input system. a reflects the non-informational aspect and b the informational aspect of input performance. For convenience, 1/b can be named as throughput which, unlike ID/MT, is conceptually a true constant.     

强制访问控制MAC的设计及实现

访问控制是计算机信息保护中极其重要的一个环节，本文针对自主访问控制的缺陷，介绍了更强力的强制访问控制(MAC)，强制访问控制是根据客体中信息的敏感标记和访问敏感信息的主体的访问级对客体访问实行限制的一种方法。本文在简单介绍了强制访问控制的优点后给出了它的形式化定义及其基本规则，最后介绍了由笔者等开发的一个安全操作系统softos中强制访问控制模块的具体设计及实现。