多传感器检测中的数据溶合技术

多传感器检测是使用多种(或多个)传感器对同一被测对象进行广泛的测量。应用多传感器检测技术和多传感器数据溶合技术对车削加工中的零件外圆尺寸检测进行了实验研究,结果表明,多传感器检测技术能够满足现代检测技术对信息的精确要求,使得检测监控系统更加准确、可靠。     

Criteria for the complementary allocation of functions in automated work systems and their use in simultaneous engineering projects

A crucial step in any system design concerns the allocation of functions between human and machine. In simultaneous engineering, function allocation is potentially an issue both in product design — if the product is a technical system itself — and in process design. It is argued that well-founded function allocation decisions in relation to the production process are of particular importance in simultaneous engineering as less and less time is allowed for compensation for inadequate or missing decisions which will impede production effectiveness. The focus of recent methods for the allocation of functions is to operationalize the concept of complementarity, meaning to provide guidelines for complementing humans by technical systems instead of replacing them gradually as technical systems become more and more sophisticated. As systems design becomes more complex, involving more and faster changes and placing higher demands on engineers as well as system operators, the idea of complementary gains importance because it stresses the need to allocate functions in a way that supports human control over the production process and the development and maintenance of the necessary skills. Looking at existing methods and instruments for the complementary allocation of functions, one is at first sight confronted with a multitude of criteria for complementarity, but to date neither a fixed set of criteria, comparable to software usability criteria, nor widely accepted methods for their measurement exist. As part of a research project concerned with the development of guidelines whose objective is to assist engineers in designing work systems according to the complementarity principle, four central criteria for complementary function allocation were identified: dynamic coupling, process transparency, human decision authority, and flexibility. These criteria and their application in a design process are illustrated by means of a case study and discussed in terms of other approaches to complementary design as well as their use for simultaneous engineering projects.

Relevance to industry

Adequate allocation of functions between human and machine is crucial for the effectiveness of any production system. With more complex and faster design processes in simultaneous engineering projects, the need for methods supporting prospective analysis and design of human-machine systems has increased even more. The article presents such a method based on the principle of complementarity between human operator and technical system and illustrates its use by means of a case study.     

“嵌埋式实时操作系统”灵活性的研究

本文阐述了“嵌埋式实时操作系统”灵活性的三个因素；可移植性、可配置性、可剪裁性及其概念和重要性，并提出了一些设计和实现的方法。     

Does prolonged sitting with limited legroom affect the flexibility of a healthy subject and their perception of discomfort?

This study examined for differences in subjective ratings of discomfort and comfort (Numerical Rating Scale) and objective measures of hamstring (Sit-Reach test), lumbar (Schöber’s test) and neck (Cervical Range of Motion) flexibility in healthy young subjects (n = 24) following 4 h of sitting on stacking chairs with or without limited legroom.When comparing the limited and unlimited legroom groups for differences in subjective and objective measures over 4 h, no significant findings were seen at the 5% level of confidence. However, differences in buttock, neck, shoulder and average discomfort were significantly negatively correlated to differences between post-warm up Sit-Reach scores (Correlation Co-efficients: −.763, −.434, −.408, and −.445; p values of .004, .034, .048, and .029, respectively). The difference in buttock discomfort was significantly negatively correlated to the difference between pre-warm up Sit-Reach scores (Correlation Coefficient: −.750; p = 0.005), post-sitting/pre-warm up and pre-sitting/post-warm up Sit-Reach scores (Correlation Coefficient: −.756; p = 0.004), and Schöber’s tests (Correlation Coefficient: −.578; p = 0.049).Although the above results suggest a relationship between a loss in flexibility and an increase in discomfort, the mechanism influencing this relationship is not clear from this study. What does appear clear is that the limiting of legroom to the parameters used in this study does not seem to exacerbate change in flexibility and discomfort which are a consequence of prolonged sitting.

Relevance to industry

Many forms of public transport provide limited legroom for their passengers, which may have an adverse affect on the user’s flexibility or experience of discomfort. Determining which objectively measurable parameters are associated with the subjective level of discomfort during sitting should allow for a greater appreciation of the changes that underpin such subjective perceptions.     

认知灵活性理论指导下的网络教学交互设计

本文首先介绍了认知灵活性理论的涵义及其关于学习和教学的观点;探讨了认知灵活性理论对开展网络教学交互设计的启发性意义;从"人-机"交互和"人-人"交互两个方面,探究了认知灵活性理论柏导下的网络教学系统中的交互设计。     

协调·弹性：新城主干道道路景观设计思考——以武汉市吴家山为例

道路景观设计以协调和弹性为原则,结合新城近远期规划,以实现新城道路弹性景观和协调城市风貌为目标,并从人性化角度分析道路交通安全通行问题。吴家山新城主干道具有距离长、道路绿化控制线宽以及现有的水资源丰富的特点。结合这些道路特点,从道路分段设计、路侧绿带设计、分车绿带设计和水网体系整合的方面来解决潜在交通问题并突显道路景观特色,同时起到净化水体、节约能源的作用。     

Flexible hybrid WDM/TDM PON architectures using wavelength selective switches

For building an optical access network, we propose some new hybrid WDM/TDM passive optical network (PON) architectures that use wavelength selective switches (WSSs) at the remote node to improve flexibility, data security and power budget. Through simulations we demonstrate that the switching capabilities of a WSS can provide additional gains in terms of wavelength usage by a better statistical multiplexing. Several WSS-based hybrid WDM/TDM PON variants are proposed and assessed. These architectures are also compared with the more commonly used hybrid WDM/TDM PONs consisting of power splitters and/or arrayed wavelength gratings (AWGs), in terms of cost and power budget.     

环艺专业基础教学中创造性思维培养的缺失

通过"创造性思维的测试"证明环境艺术设计的基础教学体系所采用的契斯恰可夫教学体系存在创造性思维训练的缺失,从而影响了艺术设计专业教学质量,对其进行创新性的改造能够使契斯哈可夫教学体系更好的为设计教学服务。     

基于有限元法的单边混合柔性铰链的性能分析

提出一种新型的单轴柔性铰链结构型式-单边混合柔陛铰链,由半个直圆柔性铰链和半个导角柔性铰链构成.通过有限元方法,分析了一组不同导角半径的单边混合铰链设计实例,结果表明单边该混合柔性铰链相对于一般混和柔性铰链与单边柔性铰链具有更高的柔度.并得到其柔度应力比,可用于定量地比较各种柔性铰链的性能差异.提出的单边混合柔性铰链为面向结构紧凑、大位移、高精度的工程应用提供了有价值的参考.     

Analytical studies for buckling and vibration of weld-bonded beam shells of rectangular cross-section

An approach to analytical solution is presented for vibration and buckling of thin-walled tubular beam shells typical of automotive structures, which are fabricated by joining sheet metal stampings along the two longitudinal edges with periodic spot welds, adhesive bonding, or combination of spot welds and bonding, known as weld bonding. Solutions are obtained for such beam shells of rectangular cross-section with two opposite ends simply supported. The beam shell is modeled as an assembly of the constituent walls and Levy-type formulation is used to obtain a series solution for the transverse displacement of each of the walls. The challenge of expressing the discrete point support conditions at the spot welds by a continuous function is addressed using the flexibility function approach used in literature. The flexibility function, used earlier to represent the flexibility distribution along weld-bonded edges of rectangular plates with periodic spot welds, is used here. The characteristic equations are obtained by satisfying the displacement, slope, shear, and moment equilibrium at the mating edges of the walls including the two weld-bonded edges and the compatibility conditions at the spot-weld locations. This approach to analytical solution, described here for thin-walled beam shells of rectangular cross-section, can be suitably adopted for more general cross-sections and joints along non-symmetric edges. A parametric study is undertaken to show the effect of aspect ratio of the beam shell, adhesive joint parameters, and the number of spot welds on the elastic buckling loads and the natural frequencies. Such parametric studies can be of use to designers in arriving at an optimal joint configuration of weld-bonded beam shells from buckling and vibration considerations.