基于知识工程(kbe)设计方法外文文献翻译(编辑修改稿)内容摘要:
manufacturing processes. Designers want a design representation that will be an exact representation of a physical prototype with both geometrical and nongeometrical attributes. Product representation has moved from the 2D orthographic drawing representation of the shape and form of the geometry, to full 3D model representation of the geometry. The design tool that is needed for the design engineering domain, clearly must have attributes of all of the tools just discussed. It must bine the geometrical representation of the CAD systems, be able to do the engineering analysis of the procedural languages and represent the design knowledge as in an expert system. A true virtual prototype contains this full range of design knowledge. ENABLING TECHNOLOGIES FOR DESIGN Types of knowledge . Knowledge’, as applied to KBE, can be divided into four types [1]: . facts, . procedures, . judgments, . control. Formalized knowledge found in handbooks such as material specifications, engineering data, ASTM standards, and equipment specifications is considered factual knowledge. Algorithmic and operative knowledge are the two forms of procedural knowledge. Numeric and nonnumeric procedures for solving a problem or acplishing some end are all elements of algorithmic procedural knowledge (APK). Facts are transformed by APK through engineering and analysis procedural knowledge (OPK) is used to create, delete, and transport facts. Examples of OPK programs are finiteelement analysis, optimization, and database management systems [1].Rules of thumb and mon bestpractices are examples of judgment knowledge. Heuristics,observations, experience, and plausible reasoning are also included in judgment knowledge. Logic and the formal principles of reasoning are fundamental to judgment knowledge 9 knowledge is metaknowledge or knowledge about knowledge. The other types of knowledge are managed by control knowledge. Pattern directed actions, anticipation of unexpected developments, and dealing with uncertainties are all features of control knowledge [1]. Knowledgebased engineering (KBE) The technology that allows the development of a true virtual prototype of a product is known as knowledgebased engineering, or KBE. KBE is the methodology for capturing and structuring knowledge about a design and its design process. KBE may be used to define engineering methods and procedures [2]. In KBE, the product structure tree (topology) is dynamic, so that KBE offers true engineering automation including application development, geometric modeling, application deployment and tools integration. Knowledgebased engineering is a programming tool used to develop a virtual prototype or a design advisor for the design of an established product in a given design domain. Dym, et al. [3] and Gonzalez, et al.[4] provide valuable overviews of KBE. Existing knowledge about a class of designs is utilized in knowledgebased engineering or design (KBE or KBD) and organized into a database format usable by puters. Detailed designs or virtual prototypes are then rapidly developed KnowledgeBased Engineering (KBE) Design Methodology 23 through the use of digital puting power, developed databases, and systems of rules. The product model which is developed in the KBE environment is a virtual prototype. A virtual prototype has all of the geometric characteristics or attributes of the product as well as the nongeometric attributes such as materials, mass properties, stress and deflection characteristics, etc. Once the virtual prototype is created, it can be used by the designers to evaluate the success or merit of the design configuration, and then modify it if desired. The product model represents the engineering intent。基于知识工程(kbe)设计方法外文文献翻译(编辑修改稿)
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