Causal Factors for Engineering Design Defects and Their Impacts

New product design as well as design revision to remedy defects is complicated by an inability to precisely predict product performance. Designers often find that they are confident about the performance of some design alternatives and uncertain about others. Similarly, alternative design changes may differ substantially in uncertainty, potential impact, and cost. This paper describes a method for including the effects of uncertainty in the evaluation of economic benefits of various design change options. The results indicate that the most profitable change option sequence depends not only on relative costs but also on the relative degree of uncertainty and on the magnitude of the potential design defects. The method demonstrates how design change alternatives can be compared using the engineering design of a beam. Finally, the validity of some common engineering change heuristics are discussed relative to their associated, quantitatively determined limits.

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Studying on Chinese Engineering Design Service Modes

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.501-504.2632 ◽

2014 ◽

Vol 501-504 ◽

pp. 2632-2637

Author(s):

Guo Hua Lu ◽

Bei Bei Zhang ◽

Hu Cheng

Keyword(s):

Life Cycle ◽

Engineering Design ◽

Management Philosophy ◽

Life Cycle Design ◽

The World ◽

Innovation Ability ◽

Efficient Information ◽

Service Mode ◽

Design Defects ◽

World Trend

Based on analyzing the characteristics of engineering design enterprises, through investigating 30 Chinese design enterprises ,the present main engineering design service modes are summarized and analyzed, furthermore the backward management philosophy, lack of the efficient information feed back mechanism ,and no enough attention to the accumulation of knowledge are uncovered as the root causes of low innovation ability, the design defects, and extensive management in Chinese design enterprises. Under the great changes taking place in modern market environment, the Chinese engineering design enterprises are required to transform for complying with market demands and the world trend, so the life cycle design service mode is put up with the development strategies for the development of the engineering enterprises.

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Resolution and measurement in the scanning electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100127256 ◽

1987 ◽

Vol 45 ◽

pp. 534-537 ◽

Cited By ~ 2

Author(s):

Michael T. Postek

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Engineering Design ◽

Resolving Power ◽

Practical Applications ◽

Instrument Resolution ◽

Accurate Definition ◽

Definition Of ◽

Scanning Electron ◽

Better Than

The term ultimate resolution or resolving power is the very best performance that can be obtained from a scanning electron microscope (SEM) given the optimum instrumental conditions and sample. However, as it relates to SEM users, the conventional definitions of this figure are ambiguous. The numbers quoted for the resolution of an instrument are not only theoretically derived, but are also verified through the direct measurement of images on micrographs. However, the samples commonly used for this purpose are specifically optimized for the measurement of instrument resolution and are most often not typical of the sample used in practical applications.SEM RESOLUTION. Some instruments resolve better than others either due to engineering design or other reasons. There is no definitively accurate definition of how to quantify instrument resolution and its measurement in the SEM.

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An Application of the HFACS Method to Aviation Accidents in Africa

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000093 ◽

2016 ◽

Vol 6 (1) ◽

pp. 33-38 ◽

Cited By ~ 4

Author(s):

Isaac Munene

Keyword(s):

Human Factors ◽

Physical Environment ◽

Human Factor ◽

Flight Training ◽

African Countries ◽

Causal Factors ◽

Aviation Accidents ◽

Factors Analysis ◽

Adverse Weather ◽

Decision Errors

Abstract. The Human Factors Analysis and Classification System (HFACS) methodology was applied to accident reports from three African countries: Kenya, Nigeria, and South Africa. In all, 55 of 72 finalized reports for accidents occurring between 2000 and 2014 were analyzed. In most of the accidents, one or more human factors contributed to the accident. Skill-based errors (56.4%), the physical environment (36.4%), and violations (20%) were the most common causal factors in the accidents. Decision errors comprised 18.2%, while perceptual errors and crew resource management accounted for 10.9%. The results were consistent with previous industry observations: Over 70% of aviation accidents have human factor causes. Adverse weather was seen to be a common secondary casual factor. Changes in flight training and risk management methods may alleviate the high number of accidents in Africa.

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