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991.
The elicitation or communication of user requirements comprises an early and critical but highly error-prone stage in system
development. Socially oriented methodologies provide more support for user involvement in design than the rigidity of more
traditional methods, facilitating the degree of user–designer communication and the ‘capture’ of requirements. A more emergent
and collaborative view of requirements elicitation and communication is required to encompass the user, contextual and organisational
factors. From this accompanying literature in communication issues in requirements elicitation, a four-dimensional framework
is outlined and used to appraise comparatively four different methodologies seeking to promote a closer working relationship
between users and designers. The facilitation of communication between users and designers is subject to discussion of the
ways in which communicative activities can be ‘optimised’ for successful requirements gathering, by making recommendations
based on the four dimensions to provide fruitful considerations for system designers. 相似文献
992.
A key role for Artificial Intelligencetechnology in electronic commerce is in findingproducts and services that meet a user'srequirements. This may be implemented as athree-stage process of requirementselicitation, product search, and finallyproduct presentation. Alternatively the searchof the product space may happen in tandem withthe requirements elicitation process. It isalso possible to use product presentation as amechanism to focus and give context torequirements elicitation. A variety ofdifferent approaches to this issue of matchingproducts to requirements have been explored inAI research. Thus, while the focus in thispaper is on different approaches torequirements elicitation, these related issuesof product search and product presentation arealso discussed in detail. The paper concludesby placing the other papers in this specialissue in the context of this structuredoverview. 相似文献
993.
To evaluate the mechanical strength of fiber reinforced composites it is necessary to consider singular stresses at the end of fibers because they cause crack initiation, propagation, and final failure. The singular stress is expressed by generalized stress intensity factors defined at the corner of fibers. As a 2D model an interaction between rectangular inclusions under longitudinal tension is treated in this paper. The body force method is used to formulate the problem as a system of singular integral equations with Cauchy-type or logarithmic-type singularities, where the unknown functions are the densities of body forces distributed in infinite plates having the same elastic constants as those of the matrix and inclusions. In order to analyze the problem accurately, the unknown functions are expressed as piecewize smooth functions using two types of fundamental densities and power series, where the fundamental densities are chosen to represent the symmetric stress singularity of 1/r
1–
1 and the skew-symmetric stress singularity of 1/r
1–
2. Then, generalized stress intensity factors at the end of inclusions are systematically calculated for various locations, spacings and elastic modulus of two rectangular inclusions in a plate subjected to longitudinal tension. 相似文献
994.
Service robotics is currently a highly active research area in robotics, with enormous societal potential. Since service robots directly interact with people, finding natural and easy-to-use user interfaces is of fundamental importance. While past work has predominately focussed on issues such as navigation and manipulation, relatively few robotic systems are equipped with flexible user interfaces that permit controlling the robot by natural means. This paper describes a gesture interface for the control of a mobile robot equipped with a manipulator. The interface uses a camera to track a person and recognize gestures involving arm motion. A fast, adaptive tracking algorithm enables the robot to track and follow a person reliably through office environments with changing lighting conditions. Two alternative methods for gesture recognition are compared: a template based approach and a neural network approach. Both are combined with the Viterbi algorithm for the recognition of gestures defined through arm motion (in addition to static arm poses). Results are reported in the context of an interactive clean-up task, where a person guides the robot to specific locations that need to be cleaned and instructs the robot to pick up trash. 相似文献
995.
996.
陈二保 《安徽工业大学学报》1996,(4)
通过实验测定1673K时碳的溶解度,得到Mn-Fc-C系和Mn-P-C系碳的溶解度公式为:Nc=0.270-0.0567×NFe和Nc=0.270-1.2911×Np.用这些公式计算出1673K时一些活度的相互作用系数,例如:等等。同时也计算出1673K时的ln和△的值. 相似文献
997.
大埋深土与井壁相互作用力学参数研究 总被引:6,自引:0,他引:6
利用高压直剪仪和三轴电液伺服机,采用模拟土与井壁接触面的土加砼混合试样,测得了在大埋深条件下,粘土和砂土与冻结法成井井壁相互作用力学参数大小。并结合实例,介绍了所得参数在井壁破裂分析中的应用。 相似文献
998.
椭圆余弦波与直墙的相互作用 总被引:3,自引:0,他引:3
本文基于椭圆余弦波理论研究了浅水立波对直墙的作用,并对工程常遇到的波浪范围进行了计算,为了检验理论成果,进行了模型试验,并根据试验结果修正了理论公式,为便于工程应用,拟合了适宜于设计者使用的经验公式。 相似文献
999.
陈述了以16Mn钢紧凑拉伸试进行的变幅加疲劳裂纹扩展行为研究。通过改变瑞利分布随机荷载谱的高荷载比和高荷载出现频率,改变得复单峰过载谱中高载出现频率,研究了这些因素对疲劳裂纹扩展和寿命的影响。实验表明:随机加载条件下,高荷载对裂纹扩展的影响没有单峰过载加载时大;高载比和高载出现频率是影响裂纹扩展的重要因素;在实验随机加载条件下;高载比和高于2.0时,高荷载才对裂纹扩展有明显的迟滞作用,高载比小于2 相似文献
1000.
作者选用了七种捕收剂在单泡管中和浮选机中研究了红柱石的浮选特性。研究结果表明,油酸钠是红柱石的最佳捕收剂。同时采用红外光谱和紫外光谱法研究了油酸钠在红柱石表面的吸附产物,从而对油酸钠与红柱石表面的作用机理提出了自己的观点。 相似文献