Cognitive shape similarity assessment for 3D part search

Mass customization aims to satisfy diverse customer requirements with high product variety while maintaining reasonable manufacturing cost and lead time. Allowing customers to perceive product differentiation is a critical factor for most design methods developed for mass customization. This study examines 3D part search from the human cognitive perspective. We designed and conducted a quasi-factorial experiment to understand how structured variations of four factors—the shape, type, dimension, and location of the feature volume of a part model—affect human judgment of part similarity. The corresponding factorial similarity values were computed with different shape signatures in the form of the feature adjacency graph. The human responses were obtained by paired comparisons of test parts, and quantified as the cognitive similarity. Statistical analysis of the experimental results showed that the type and shape factors played an important role in the subjects’ judgments. Back-propagation neural networks were trained to model the correlations between the cognitive and the factorial similarity values. The performance of the networks validates our idea of incorporating human cognition into assessment of 3D part similarity. This study presents a systematic approach for personalized part search that reflects individual perception of shape similarity.     

产品外形设计中客户感性认知模型及应用

为了更好地利用客户的感性认知支持产品外形设计活动,提出一种产品外形设计中客户感性认知与产品外形特征关联模型.在分析产品外形设计中所涉及的客户感性认知特点的基础上,建立产品外形特征要素与客户感性认知要素的关联模式;以认知行为为标准,利用特征匹配实现了客户感性认知的识别与相似性分析;提出了基于模糊认知图的客户感性认知与产品外形特征关联模型,利用蚁群聚类算法确定模糊认知图的结构及邻接矩阵,从而获取客户感性认知以指导产品的外形设计.最后通过实例验证了该模型的有效性和实用性.     

时间序列特征表示与相似性度量研究综述

时间序列是将同一指标的数值按照时间的先后顺序排列组成的一组随机数列.随着科学技术的蓬勃发展,时间序列在数据挖掘领域中的应用变得越来越广泛.综合分析了近年来时间序列在数据挖掘领域的文献成果,对时间序列特征表示和相似性度量方法进行了阐述.针对时间序列特征表示方法,从非数据适应性方法、数据自适应性方法、基于模型的方法三方面进...     

面向虚实融合的人机交互

面向虚实融合的人机交互涉及计算机科学、认知心理学、人机工程学、多媒体技术和虚拟现实等领域，旨在提高人机交互的效率，同时响应人类认知与情感的需求，在办公教育、机器人和虚拟/增强现实设备中都有广泛应用。本文从人机交互涉及感知计算、人与机器人交互及协同、个性化人机对话和数据可视化等4个维度系统阐述面向虚实融合人机交互的发展现状。对国内外研究现状进行对比，展望未来的发展趋势。本文认为兼具可迁移与个性化的感知计算、具备用户行为深度理解的人机协同、用户自适应的对话系统等是本领域的重要研究方向。     

A goal-programming enhanced collaborative optimization approach to reducing lifecyle costs for naval vessels

Understanding the trade-offs involved in assessing lifetime cost for engineering systems requires understanding trends in various engineering disciplines that require significantly different analysis methods to efficiently explore. The corresponding design spaces can be flat, defined by weak minima, and thus difficult to understand using traditixonal optimization methods. This paper presents a new multi-disciplinary framework that uses a goal-programming enhanced multi-objective collaborative optimization (eMOCO) approach to facilitate the development of the spaces. In order to further increase its efficiency in discrete or flat spaces well-suited to evolutionary optimization a unique discipline level genetic algorithm is proposed. Naval vessels are an example of an engineering system that has a difficult design space with respect to lifetime cost, however, one where it is critical to understand. As these costs are increasing, they are becoming limiting factors in a vessel’s operational life. Though they are so important, the interaction between different cost categories such as production and operation has not been explored in depth and is not always clear. Understanding the trade-offs between different aspects of a vessel’s total ownership costs early in the design stage can aid in the production of new ships where they are minimized. The proposed framework is verified on mathematical problems, and then used to develop trade-spaces between resistance and production for a nominal naval combatant vessel. These trade-spaces show both the knowledge gained by designers in understanding these trade-offs and the ability of the proposed eMOCO framework to develop them effectively.     

基于可视化技术的网络协议分析

研究TCP/UDP协议过程分析方法以及基于可视化技术的协议实现过程,实现一个基于Linux和GTK+的网络协议分析软件。通过对TCP/UDP协议的可视化分析,追溯网络数据的传输过程,将网络数据之间的关系和TCP/UDP协议的实现过程以可视化技术进行展现,并将数据转化为可读性强并易于理解的形式展现出来,有助于网络协议学习者更加直观地了解TCP协议的工作原理,从而更好地去分析并设计应用层的协议。     

Comprehending object and process models: an empirical study

We report the results of an empirical study comparing user comprehension of object oriented (OO) and process oriented (PO) models. The fundamental difference is that while OO models tend to focus on structure, PO models tend to emphasize behaviour or processes. Proponents of the OO modeling approach argue that it lends itself naturally to the way humans think. However, evidence from research in cognitive psychology and human factors suggests that human problem solving is innately procedural. Given these conflicting viewpoints, we investigate empirically if OO models are in fact easier to understand than PO models. But, as suggested by the theory of cognitive fit, model comprehension may be influenced by task-specific characteristics. We therefore compare OO and PO models based on whether the comprehension activity involves: 1) only structural aspects, 2) only behavioral aspects, or 3) a combination of structural and behavioral aspects. We measure comprehension through subjects' responses to questions designed along these three dimensions. Results show that for most of the simple questions, no significant difference was observed insofar as model comprehension is concerned. For most of the complex questions, however, the PO model was found to be easier to understand than the OO model. In addition to describing the process and the outcomes of the experiments, we present the experimental method employed as a viable approach for conducting research into various phenomena related to the efficacy of alternative systems analysis and design methods. We also identify areas where future research is necessary, along with a recommendation of appropriate research methods for empirical examination     

Topological dynamics characterization for LEO satellite networks

The highly topological dynamics characterizes the most fundamental property of satellite networks with respect to terrestrial ones. The manifest feature directs the researches on various aspects of satellite networks, including protocol architecture investigations, routing protocol and reliable transmission control protocol design and enhancement, etc. This paper systematically quantifies the dynamical activities of regular low earth orbit (LEO) satellite network topologies. The number and length of network snapshots are formulated concisely. With this work, it compensates for the simplified topological assumptions in many LEO satellite network related researches. The thorough understanding of this basic feature not only provides for an accurate quantification of network behavior for researchers on satellite network community, but also could act as a guidance for future satellite constellation design and optimization.     

Open a Window to the Cognitive Work Process! Pointillist Analysis of Man–Machine Interaction

Technological progress keeps on changing our lives and our work. We can only improve this mutual influence between human and technology if we understand the impact of technology on the work process, and if we are also able to share this understanding with other people in the design process. Quantitative assessment methods like workload offer at least a keyhole to the work process, but only additional concepts like situation awareness or usability in an appropriate combination with qualitative aspects can open this keyhole into a wider window. The pointillist approach uses a powerful metaphor, borrowed from the arts, to combine quantitative with qualitative aspects systematically. Based on this approach, a tool for human factors analysis was built and used to analyse the interaction between a pilot and an assistant system in a simulator. Three examples illustrate the possible interplay between quantitative and qualitative aspects of the approach.     

液化气定量装车监控系统

本系统通过PC机的串口采集现场仪表的数据,监控装车的过程,并统计管理各项数据。该系统有很强的通讯能力、现场数据的实时检测能力及强大的数据管理和良好的图形界面。文章侧重于实现基于Modbus协议的数据通信的设计,主要讨论了以PC机为主站,带协议接口的智能仪表为从站,使用Modbus协议实现两者间数据传输的方法。概述了RS-232和RS-485串行通信的特点,介绍了Delphi串口通信编程的方法和控件的使用。     

Comparison of Four Subjective Methods for Image Quality Assessment

To provide a convincing proof that a new method is better than the state of the art, computer graphics projects are often accompanied by user studies, in which a group of observers rank or rate results of several algorithms. Such user studies, known as subjective image quality assessment experiments, can be very time‐consuming and do not guarantee to produce conclusive results. This paper is intended to help design efficient and rigorous quality assessment experiments and emphasise the key aspects of the results analysis. To promote good standards of data analysis, we review the major methods for data analysis, such as establishing confidence intervals, statistical testing and retrospective power analysis. Two methods of visualising ranking results together with the meaningful information about the statistical and practical significance are explored. Finally, we compare four most prominent subjective quality assessment methods: single‐stimulus, double‐stimulus, forced‐choice pairwise comparison and similarity judgements. We conclude that the forced‐choice pairwise comparison method results in the smallest measurement variance and thus produces the most accurate results. This method is also the most time‐efficient, assuming a moderate number of compared conditions.     

A reference based analysis framework for understanding anomaly detection techniques for symbolic sequences

Anomaly detection for symbolic sequence data is a highly important area of research and is relevant in many application domains. While several techniques have been proposed within different domains, understanding of their relative strengths and weaknesses is limited. The key factor for this is that the nature of sequence data varies significantly across domains, and hence while a technique might perform well in its original domain, its performance is not guaranteed in a different domain. In this paper, we aim at establishing this understanding for a wide variety of anomaly detection techniques for symbolic sequences. We present a comparative evaluation of a large number of anomaly detection techniques on a variety of publicly available as well as artificially generated data sets. Many of these are existing techniques while some are slight variants and/or adaptations of traditional anomaly detection techniques to sequence data. The analysis presented in this paper allows relative comparison of the different anomaly detection techniques and highlights their strengths and weaknesses. We extend the reference based analysis (RBA) framework, which was originally proposed to analyze multivariate categorical data, to analyze symbolic sequence data sets. We visualize the symbolic sequences using the characteristics provided by the RBA framework and use the visualization to understand various aspects of the sequence data. We then use the characterization done by RBA to understand the performance of the different techniques. Using the RBA framework, we propose two anomaly detection techniques for symbolic sequences, which show consistently superior performance over the existing techniques across the different data sets.     

恶意软件网络协议的语法和行为语义分析方法

网络协议逆向分析是恶意软件分析的一项重要内容.现有的网络协议逆向分析方法主要考虑获取消息格式和协议语法,缺少数据的行为语义,导致分析者难以在网络数据和恶意软件行为之间建立起对应关系.提出一种网络协议的语法规范和字段行为语义分析方法,该方法利用基于虚拟执行环境的动态程序分析技术,通过分析恶意软件对网络数据的解析过程提取协议语法信息,并根据恶意软件对协议字段的使用方式获取字段的程序行为语义.通过结合API拦截和指令执行监控,该方法降低了分析复杂度,提高了分析效率.在所设计和实现的原型系统Prama(protocol reverse analyzer for malware analysis)上的实验结果表明,该方法能够较为准确地识别字段,提取协议语法规范,并能在命令字段与其引起的程序行为之间建立起有效的对应关系.     

基于协议分析的入侵检测研究综述

入侵检测技术就是对入侵行为的发觉,为了提高从大量数据中发现攻击行为的能力,协议分析被引入入侵检测领域,成为整个检测系统的有力补充。本文根据网络协议标准,将现有的基于协议分析的入侵检测技术从有线网络和无线局域网2个方面进行归纳和总结,并给出了进一步研究建议。     

基于ACT-R模型的互联网交互模式库设计

论文以用户行为中心的交互设计理念,提出了基于AC T-R认知模型的新型交互模式库的组织方法,并给出相应的界面评估方法和界面效率。设计者可根据设计需求和关注点发掘交互模式,并参考模式对应的认知原则以及界面效率,对交互方案进行选择和优化。     

基于能力培养的《软件工程》课程实践教学方案设计

首先提出了该实践课程的定位与培养目标,而后从实践教学体系设计的指导思想、实践教学内容和教学方法设计、考核方式与评价方法、实践教学效果几个方面阐述了《软件工程》课程实践教学方案设计的主要内容。通过设计该方案,进一步培养学生的应用能力和实践能力,即有效培养学生的项目分析、设计与技术开发能力,从而提高学生的就业竞争力。     

Mental models: helping users understand software

The author examines the nature and styles of mental models and how users build them. She discusses several principles of user-interface design that have a bearing on the ability of users to create mental models. They are consistency, simplicity, completeness, layering of functionality, and useful feedback. The author considers the use of protocol analysis and knowledge-acquisition methods to assess users' mental models. She examines the concept of building user models into the design of a system.<>