COMPLEXITY OF DESCRIPTIONS OF SYSTEMS: A FOUNDATIONAL STUDY

By definition (Webster) a system is deemed complex and complicated when the interconnection or arrangement of its parts is difTicult to trace or understand. Tracing and understanding are associated with cerebral learning processes. By the aid of a previously developed model for such processes we can study the difficulties that define the complexity impressions and thus provide a foundational, rather than methodological, study of complexity. The nature of complexity as difficulty of perception suggests that a complexity classification should, in general, be more difficult than a simplicity classification. This thesis is discussed and applied with a mathematical notion of degree of difficulty.     

工程图形的两种快速细化方法

文中就工程扫图形扫描输入及模式识别的基本问题之一－细化处理问题作了探讨，提出了两种新的快速细化方法，利用串行扫描，分别通过对称侵蚀和单向侵蚀的方法，获取图形目标骨轲，算法简单，省内存，处理速度快，以开放的计算机上实现，软件运行结果表明，这两种算法对要求精度较高的机械图形及逻辑电路，工艺流程图，科等一般工程图形进行处理，是十分有效的。     

Einfluss von IT-Service-Management-Frameworks auf?die?IT-Organisation

Over 90 percent of companies are estimated to use IT Service Management (ITSM) frameworks, yet there is little research on their benefits to the Information Technology (IT) department and the business units. An international survey of 491 firms was conducted to assess the benefits of the IT Infrastructure Library (ITIL), the de-facto ITSM framework, specifically on how these benefits evolve as companies increase their adoption of the ITIL model. Also studied are the perception of challenges of the implementation and the number of ITIL processes implemented in relation to the progress of the adoption of ITIL. Results indicate that as the maturity of implementation increases, the perception of challenges decreases. Findings also show that as the maturity of implementation increases, the number of realized benefits increases, as well as the number of implemented ITIL processes. Implications for practitioners and researchers are also discussed.     

Comparative studies of perceived vibration strength for commercial mobile phones

A mobile phone, also known as cell phone or hand phone, is among the most popular electrical devices used by people all over the world. The present study examines the vibration perception of mobile phones by co-relating the relevant design parameters such as excitation frequency, and size and mass of mobile phones to the vibration perception survey by volunteers. Five popular commercially available mobile phone models were tested. The main findings for the perception surveys were that higher vibration frequency and amplitude of the peak acceleration would result in stronger vibration perception of the mobile phones. A larger contact surface area with the palms and figures, higher peak acceleration and the associated larger peak inertia force may be the main factors for the relatively higher vibration perception. The future design for the vibration alert of the mobile phones is likely to follow this trend.     

基于VB的宏微两级定位平台精度评定软件系统开发

介绍了一种用于宏微两级精密定位平台精度评定的软件系统,包括系统的评定标准、评定方法以及软件系统的组成.该系统基于VB开发,实现了对定位平台进行精度评定所需数据的采集、处理、保存以及评定结果的显示.给出了软件系统的界面及评定结果的部分示图.     

水利感知网顶层设计与思考

智慧水利是水利信息化新的发展阶段,是智慧社会的重要组成。水利感知网是智慧水利的基础部分,动态监测、加工处理、汇集各类水利数据和信息。以全国水利行业的视角,通过水利业务需求,研究分析水利感知对象、内容、要素,以及实现的技术与手段,从顶层对智能感知终端、系统、体系等的结构和内容进行研究和设计。     

基于误差位和小数位的乘积有效数字自动提取方法

提出基于误差位和小数位的乘积有效数字自动提取方法。该方法由相乘数据的有效位数决定乘积的误差位数,再由乘积的总位数与其误差位数求出乘积的有效位数,进而提取其有效数字。考虑到乘积在计算机中溢出和非溢出两种情况,采用乘积的整数位数和小数位数来计算乘积的总位数,乘积的小数位数由相乘数据的小数位数求出,乘积的整数位数通过计数的方法得到。理论分析表明,在任意情况下,两个有效数字相乘,其积的误差位数与两数中位数较大的有效数字位数相同。实验结果表明,有效数字提取算法能对计算机存储范围内的乘积有效数字进行正确、完整、有效地提取,且满足大学物理实验数据自动处理的要求。     

Perception network for the team of indoor mobile robots: concept,architecture, implementation

The concept of perception network with application to the distributed perception processes taking place among mobile robots operating on the shared shop-floor is discussed. Its relationship with the distributed environment modeling is pointed out. The concept of geometrical database is combined with multiple classes of maps generated with particular physical sensors, in order to obtain the world model. The logical and functional structure of the perception network has been proposed to reflect the semantics of the transportation system consisting of the team of indoor mobile robots.     

关于一般图形Voronoi图的离散构造法的研究

生成元为任意图形的一般图形Vomnoi图，由于其生成元的任意性，使得构造一般图形Voronoi图的算法均比较复杂。本文给出了在生成元边界上选取母点，利用点为生成元的Voronoi图的离散画法进行构造，从而得到一般图形Voronoi图的离散构造法。与其它算法相比，该算法的实现与生成元的形状无关，无需复杂计算，无需考虑误差控制，因而更加实用，效率也更高。实验结果表明，该算法简单，具有较高的理论价值和应用价值。     

一种现场总线设备通信栈体系结构研究及应用层的设计与实现

本文从通信方式上分析了现场总线通信栈的体系结构,对其通信方式的机理作了深入的研究探讨,着重讨论了不同节点的用户层实体之进行通信的三维通信关系模型。     

ORACLE／CASE剖析

ＣＡＳＥ是将计算机辅助技术应用于软件工程而产生的一种高科技领域,是当前软件设计开发集成环境与工具的重要研究方向,对于提高软件产品的生产率和质量具有重要的现实意义。本文对ＯＲＡＣＬＥ／ＣＡＳＥ系统进行了剖析,讨论了ＣＡＳＥ基本成分,ＯＲＡＣＬＥ／ＣＡＳＥ工具组及体系结构,探讨其内部结构,各成分作用及设计的基本过程。     

Language and vision: A single perceptual mechanism?

Independent work on cognitive models of visual perception and of perception of lexical items reveals a common framework underlying the two sets of cognitive mechanisms posited. From these two classes of model — one visual and the other linguistic — a unifying structure has been extracted. The integrated model is presented, discussed, and some general implications for the notion of unified theories of visual and linguistic perception are considered. In particular, we are able to demonstrate a similar structuring of contextual, or top-down, information, and a similar pattern of interplay between serial and parallel processes as well as between top-down and bottom-up information. In addition, several common problems, such as the role of value parameters in perception, are identified.     

Parallax cues in the design of graphics used in technical education to illustrate complex spatial problems

The explanation of certain 3D concepts is based on 2D drawings. These drawings should contain certain depth cues, such as perspective and overlapping. Until recently, parallax has not been used as a depth cue. Nevertheless, new technologies allow it to be incorporated. This forms the background to our study of the design of interactive educational resources and stereoscopic graphics. The results obtained demonstrate that (1) the use of parallax cues improves the interpretation of the figures and (2) that the assistance they afford is most appreciated by the students with less highly developed spatial perception.     

机器人室内语义建图中的场所感知方法综述

场所感知问题是机器人语义地图研究的关键问题之一,本文对室内语义地图相关的场所感知方法进行全面综述.首先,根据近年的文献给出场所概念的描述性定义,对研究中涉及的相近术语和概念进行辨析,澄清研究对象和研究主题.然后,根据实现场所感知目标所采用的线索对已有方法进行分类介绍.主要分成3个大类:基于环境布局几何信息的方法、基于环境布局视觉信息的方法、基于用户指导信息的方法,其中各类又根据所用信息特点细分为若干子类.除此之外,将一些特殊研究方法单独归类进行补充说明.阐述各类别方法对场所感知问题的解决思路和工作原理,并指出各种方法特点和局限性.最后,分析了该领域存在的主要问题,并对未来研究方向进行了讨论和展望.     

A method of rotating areas on a raster scan graphic display

The method presented here permits an area of a picture held in a frame store to be rotated in the plane without recourse to a data structure or other picture definition. It is therefore suitable for use with digitized images and hand-drawn ones. Four techniques based on interpolation are compared and some performance figures are given. In addition, the effect of the computation on the appearance of the picture is discussed, a specific example being included.     

Proposal of interactive applications to enhance student’s spatial perception

The aim of this series of applications is to enhance students’ spatial perception capacity by means of exercises that require the student to concentrate on mentally recreating the figures represented.     

Graphical methods for investigating the finite-sample properties of confidence regions

No satisfactory method for measuring and presenting the performance of confidence regions can be found in the literature. Techniques for measuring the effectiveness of confidence regions and for the graphical display of simulation evidence regarding the coverage and effectiveness of confidence regions are developed and illustrated. Three types of figures are discussed: called coverage plots, coverage discrepancy plots, and coverage effectiveness curves, which makes it possible to show the “genuine” effectiveness, rather than a spurious nominal effectiveness. These figures are used to illustrate the finite sample properties of autoregressive parameter confidence regions in the context of AR(1) processes.     

Perception of human motion with different geometric models

Human figures have been animated using a variety of geometric models, including stick figures, polygonal models and NURBS-based models with muscles, flexible skin or clothing. This paper reports on experimental results indicating that a viewer's perception of motion characteristics is affected by the geometric model used for rendering. Subjects were shown a series of paired motion sequences and asked if the two motions in each pair were the same or different. The motion sequences in each pair were rendered using the same geometric model. For the three types of motion variation tested, sensitivity scores indicate that subjects were better able to observe changes with the polygonal model than they were with the stick-figure model     

The neural representation of time: an information-theoretic perspective

A prominent finding in psychophysical experiments on time perception is Weber's law, the linear scaling of timing errors with duration. The ability to reproduce this scaling has been taken as a criterion for the validity of neurocomputational models of time perception. However, the origin of Weber's law remains unknown, and currently only a few models generically reproduce it. Here, we use an information-theoretical framework that considers the neuronal mechanisms of time perception as stochastic processes to investigate the statistical origin of Weber's law in time perception and also its frequently observed deviations. Under the assumption that the brain is able to compute optimal estimates of time, we find that Weber's law only holds exactly if the estimate is based on temporal changes in the variance of the process. In contrast, the timing errors scale sublinearly with time if the systematic changes in the mean of a process are used for estimation, as is the case in the majority of time perception models, while estimates based on temporal correlations result in a superlinear scaling. This hierarchy of temporal information is preserved if several sources of temporal information are available. Furthermore, we consider the case of multiple stochastic processes and study the examples of a covariance-based model and a model based on synfire chains. This approach reveals that existing neurocomputational models of time perception can be classified as mean-, variance- and correlation-based processes and allows predictions about the scaling of the resulting timing errors.