二进制差异演化算法及其应用

针对传统差异演化算法（Differential Evolution）无法求解采用二进制编码问题的缺点,通过引入“少数服从多数”原则,提出一种解决二进制编码问题的差异演化算法—二进制差异演化算法。5个测试函数和4个背包问题的仿真实验表明了文中提出算法在解决二进制编码问题上的有效性。     

Macro-level software evolution: a case study of a large software compilation

Software evolution studies have traditionally focused on individual products. In this study we scale up the idea of software evolution by considering software compilations composed of a large quantity of independently developed products, engineered to work together. With the success of libre (free, open source) software, these compilations have become common in the form of ‘software distributions’, which group hundreds or thousands of software applications and libraries into an integrated system. We have performed an exploratory case study on one of them, Debian GNU/Linux, finding some significant results. First, Debian has been doubling in size every 2 years, totalling about 300 million lines of code as of 2007. Second, the mean size of packages has remained stable over time. Third, the number of dependencies between packages has been growing quickly. Finally, while C is still by far the most commonly used programming language for applications, use of the C++, Java, and Python languages have all significantly increased. The study helps not only to understand the evolution of Debian, but also yields insights into the evolution of mature libre software systems in general.

硬软件交互的可靠性建模及其应用

开发了一种统一的可靠性模型,该模型对系统的硬件失效、软件失效和软硬件交互失效都可以作出解释。硬软件失效可以由熟知的建模方法来解决。而提出了一套利用马尔可夫过程来捕获硬软件交互失效的建模方法论,通过将其应用到真实的通信系统来说明该硬软件混合的建模方法。     

Integration of heterogeneous repositories based on ontologies for EC applications development

Recently, due to the significance of Web applications in the business field, it has become important how quickly an application can be developed from a business idea. This paper proposes a method that rebuilds heterogeneous repositories required for business applications development into a multi-grain-size repository based on ontologies. The proposed repository consists of component libraries and their use patterns from a level on a high abstraction such as enterprise activities to the concreteness level of software. Our repository supports the whole process of business application development including modeling enterprises and business activities and deploying models as software with components. Finally, we devise a development methodology of on-line business such as Web shopping with the framework and software component based on free and commercial application servers.     

遗传算法在软件项目管理中的应用及研究

遗传算法（genetic algorithms,GAs）因其能适应任意限制条件和目标问题,被普遍应用在各种调度优化问题中,但是针对于特定的软件项目管理问题和环境,没有系统的研究和分析.通过对传统调度问题中遗传算法的研究,结合软件项目管理的特点,提出和比较了基于任务和基于时间轴的两种模型,以及GA编码和算子的设计.并通过与其他启发式算法上的性能比较实验,确认了GA在软件项目管理问题中的优势.     

A survey on software defined networking and its applications

Software defined networking (SDN) achieves network routing management with logically centralized control software that decouples the network data plane from the control plane. This new design paradigm greatly emancipates network innovation. This paper introduces the background of SDN technology with its design principles, explains its differentiation, and summarizes the research efforts on SDN network architecture, components and applications. Based on the observation of current SDN development, this paper analyzes the potential driving forces of SDN deployment and its future trend.     

基于Web的动态几何软件领域模型及其应用

动态几何软件以其动态、直观的特点广泛应用于几何约束作图。针对数据结构缺乏对动态几何领域内可复用的抽象描述的问题,提出一种动态几何软件领域模型的设计方法。首先经过领域分析来识别并划分出最基本的上下文边界,然后通过领域模型设计得到动态几何软件核心领域模型,最后在体系结构建模过程中,在纵向与横向两个维度对动态几何软件进行解耦。实验结果表明,利用该领域模型设计方法研发的动态几何软件能正确地处理图形在临界位置退化的情形。该模型表达的领域知识同时适用于二维及三维的动态几何软件,并支持对不同设备分别设计布局与交互,实现了领域知识的高层次复用。     

Predicting operational software availability and its applications to telecommunication systems

It is essential to predict customer-perceived software availability during software development and determine when to release the software to maintain a balance among time-to-market, development cost and software quality. This paper presents methods and procedures to predict software failure rates from a user perspective in system test phases and to reverse-engineer in order to estimate software release time for given availability targets. Software reliability analysis is conducted based on non-homogenous Poisson process models. Software system test data of current release are used to estimate the number of residual faults by the end of system tests and data of previous releases or similar products (including system test data, post-system test data and field failure data) provide a means to predict a user-perceived average failure rate of a fault. Software system availability can be predicted from these estimates. Both execution and calendar times are considered. A software resource utilization model is developed to transfer one testing time to another. A telecommunications application illustrates how to calculate the failure rate and testing time to meet the software availability requirements.     

Development and applications of a software tool for diarthrodial joint analysis

This paper describes a new software environment for advanced analysis of diarthrodial joints. The new tool provides a number of elaboration functions to investigate the joint kinematics, bone anatomy, and ligament and tendon properties. In particular, the shapes and the contact points of the articulating surfaces can be displayed and analysed through 2D user-defined sections and fittings (lines or conics). Ligament behaviour can be evaluated during joint movement, through the computation of elongations, orientations, and fiber strain. Motion trajectories can be also analysed through the calculation of helical axes, instantaneous rotations, and displacements in specific user-chosen coordinate reference frames. The software has an user-friendly graphical interface to display four-dimensional data (time-space data) obtained from medical images, navigation systems, spatial linkages or digitalizers, and can also generate printable reports and multiple graphs as well as ASCII files that can be imported to spreadsheet programs such as Microsoft Excel.     

Hamming weight pyramid - A new insight into canonical signed digit representation and its applications

Signed-power-of-two terms are widely used in design automation algorithms for digital filter synthesis and optimization, linear transformation and other multiple constant multiplication problems. In these applications, the computation efficiency or solution quality tends to degrade with the number of nonzero digits in the signed digit representation of the a priori fixed coefficients. This paper provides a new perspective to interpret the hamming weights of fixed-point coefficients represented in signed-power-of-two terms with minimal number of nonzero digits, called the minimal signed digit (MSD) representation. A new hamming weight pyramid (HWP) is proposed to succinctly compress the information about the distribution of the hamming weights of canonical signed digit (CSD) representation in a visually appealing manner for analysis and synthesis. CSD is a unique and popularly used subset of the general MSD representation. Many interesting properties of CSD are uncovered in this regularly structured HWP. These properties are exploited to develop a novel and elegant algorithm for the direct conversion of decimal number to CSD representation. We also show that the HWP can also be employed to overcome the limit imposed on the word length of the coefficients for the reduced adder graph (RAG) algorithm and filter coefficient synthesis.     

Evolution styles: foundations and models for software architecture evolution

As new market opportunities, technologies, platforms, and frameworks become available, systems require large-scale and systematic architectural restructuring to accommodate them. Today’s architects have few techniques to help them plan this architecture evolution. In particular, they have little assistance in planning alternative evolution paths, trading off various aspects of the different paths, or knowing best practices for particular domains. In this paper, we describe an approach for planning and reasoning about architecture evolution. Our approach focuses on providing architects with the means to model prospective evolution paths and supporting analysis to select among these candidate paths. To demonstrate the usefulness of our approach, we show how it can be applied to an actual architecture evolution. In addition, we present some theoretical results about our evolution path constraint specification language.     

Experience on knowledge-based software engineering: A logic-based requirements language and its industrial applications

A formal requirements specification language plays an important role in software development. Not only can such language be used for stating requirements specification, but also can be used in many phases of software development life cycle. The FRORL project started from constructing a language with a solid logical foundation and further expanded to research in verification, validation, requirements analysis, debugging, and transformation. Research in this project aided in some industrial applications in which a code generation tool produced software for embedded systems. This article reports the experiences gained from this project and states the value of research in knowledge-based software engineering.     

A robotic software for intelligent applications

This study addresses the development of a novel intelligent robotic software system which can control a low-cost five DOF robotic arm and allows the robot to be able to play Tic-Tac-Toe, a simple board game. The paper first aims to introduce proposed software and then details the application developed, including image processing, and decision making steps.     

求解需求可拆分车辆路径问题的改进的金字塔演化策略

为了更加合理地求解需求可拆分的车辆路径问题（SDVRP）,克服传统先路径后优化两阶段的求解方法容易陷入局部最优的缺点,以及解决智能优化算法在优化阶段未能将竞争与协作有机地融合为一体的问题,以配送路径最短和配送车辆最少为优化目标,提出了一种改进的金字塔演化策略（IPES）。首先,以金字塔为基础,提出了求解SDVRP的编码、解码方式以及层级间的协作策略;其次,根据遗传算法的随机、“适者生存”的高度并行、自适应等特点,以及金字塔结构各层分工不同,设计了一种适合SDVRP的自适应邻域算子,使得算法能够快速收敛到最优;最后,得到最优解。相较于分段求解算法、聚类算法、粒子群算法、人工蜂群算法、禁忌搜索算法,四个仿真实验的结果表明,在求解各案例的最优路径时,所提IPES的求解精度分别至少提升了0.92%、0.35%、3.07%、9.40%,验证了在求解SDVRP时,IPES具有良好的性能。