A Probabilistic-Based Design Model for Achieving Flexibility in Design

1999 ◽  
Vol 121 (1) ◽  
pp. 77-83 ◽  
Author(s):  
W. Chen ◽  
C. Yuan

In this paper we propose the use of a probabilistic-based design model as a basis for providing the flexibility in a design process that allows designs to be readily adapted to changing conditions. Our proposed approach can be used to develop a range of solutions that meet a ranged set of design requirements. Meanwhile, designers are allowed to specify the varying degree of desirability of a ranged set of design performance based on their preferences. The Design Preference Index (DPI) is introduced as a design metric to measure the goodness of flexible designs. Providing the foundation to our work are the probabilistic representations of design performance, the application of the robust design concept, and the utilization of the compromise Decision Support Problem (DSP) as a multiobjective decision model. A two-bar structural design is used as an example to demonstrate our approach. Our focus in this paper is on introducing the probabilistic-based design model and not on the results of the example problem, per se.

Author(s):  
Wei Chen ◽  
Chenhao Yuan

Abstract In the early stages of product development, the transformation between design requirements and design solutions often involves uncertainties when specifying the desired target value for the performance expressed in design requirements. Additionally, to provide flexibility for later development, the design solution obtained is desired to be a range rather than a single solution. Our primary focus in this paper is on developing a probabilistic-based design model as a basis for providing the flexibility that allows designs to be readily adapted to changing conditions. This is obtained by developing a range of design solutions which meet a ranged set of design requirements. Meanwhile, designers are allowed to specify the varying degree of desirability of a ranged set of design requirements based on their preferences. The Design Preference Index (DPI) is introduced as a design metric to measure the goodness of flexible designs. Providing the foundation to our work are the probabilistic representations of design performance, the application of robust design concept, and the utilization of the compromise Decision Support Problem (DSP) as a multi-objective decision model. A two-bar structural design is used as an example to demonstrate our approach. Our focus in this paper is on introducing the probabilistic-based design model and not on the results of the example problem, per se.


Alloy Digest ◽  
1977 ◽  
Vol 26 (3) ◽  

Abstract FROSTLINE is a fine-grain, columbium-treated carbon steel designed to be an economical solution to structural design requirements at cold temperatures. Available in plate thicknesses up to 6 inches, it offers high levels of toughness at temperatures to 80 F and higher strength levels than conventional carbon steels. Frostline also offers excellent welding characteristics, because of its low carbon equivalent. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness. It also includes information on forming, heat treating, and machining. Filing Code: CS-67. Producer or source: Lukens Steel Company.


2020 ◽  
Vol 316 ◽  
pp. 02001
Author(s):  
Jing Sheng ◽  
Aamir Sohail ◽  
Mengguang Wang ◽  
Zhimin Wang

In order to realize the need for lightweight automobiles through replacing steel with plastics, the research and development of the plastic clutch pump body based on the friction welding was carried out. For the clutch pump body connected by friction welding process between the upper pump body and the lower pump body, the technical requirements of pressure 14 MPa and durability (high temperature 7.0 × 104 times, room temperature 7.0 × 105) are required. The structure type of the upper and lower pump bodies of the end face welding type was proposed. Through the static analysis of the pump body and weld and the mechanical analysis under the working condition, the structure of the clutch pump body (upper and lower pump body) was determined. According to the established welding process, the pressure of the clutch pump body is more than 15 MPa, and the number of high-temperature durable circulation and the number of room temperature durable circulation also reached 7.2×104 and 7.3×105 times respectively. The results show that the structural design of a clutch pump body meets the design requirements.


2011 ◽  
Vol 105-107 ◽  
pp. 403-407
Author(s):  
Xiao Chun Zhang ◽  
Yuan Qi Cai

Shell stiffeners are used effectively to prevent preferential local buckling of LNG tank shell. In this paper, Finite element method (FEM) is applied to pay attention to the thermal analysis on the shell stiffeners of double steel wall LNG storage tank. The structural requirements according to British Standard 7777-2:1993 has been considered and then some dimensional adjustments of shell stiffeners are made to evaluate their influence on the thermal field of double steel wall LNG storage tank. Temperature distributions and heat flux of different dimensional shell stiffeners are presented. Though the analysis of results, it puts forward the conclusion that the dimensional design of shell stiffeners used in double steel wall LNG storage tank shall take not only the structural design requirements but also the thermal design ones into consideration in order to finally save cost in both construction and normal operation.


Author(s):  
Yunwen Feng ◽  
Jiale Zhang ◽  
Xiaofeng Xue ◽  
Xiaoping Zhong ◽  
Wei Xie

Aircraft lug joint is the key part of load transfer. In order to improve the safety of lug joint, on the premise of meeting the design requirements of static strength and fatigue, the composite connection lug structure design technology of different metal materials is proposed in this paper. Firstly, the damage safety design and life reliability analysis of the lug structure are studied theoretically. Secondly, based on the concept of damage safety design and the design principle of deformation coordination, the design method of composite connection lug with deformation coordination is proposed, and the thickness ratio of single ear is 0.8:1:0.8. Finally, the reliability of the composite lug is analyzed. The results show that the structural design scheme of aluminum-titanium composite ear piece can meet the requirements of static strength and damage tolerance, and compared with the conventional ear structure, the failure probability of structure mission life is greatly reduced when the weight of the composite connection lug is only increased by 4.9%. The proposed method can effectively guide the structural design of composite ear piece.


Author(s):  
Tiago Oliveira ◽  
José Neves ◽  
Paulo Novais

The prevalence of situations of medical error and defensive medicine in healthcare institutions is a great concern of the medical community. Clinical Practice Guidelines are regarded by most researchers as a way to mitigate theseoccurrences; however, there is a need to make them interactive, easier to update and to deploy. This paper provides a model for Computer-Interpretable Guidelines based on the generic tasks of the clinical process, devised to be included in the framework of a Clinical Decision Support System. Aiming to represent medical recommendations in a simple and intuitive way. Hence, this work proposes a knowledge representation formalism that uses an Extension to Logic Programming to handle incomplete information. This model is used to represent different cases of missing, conflicting and inexact information with the aid of a method to quantify its quality. The integration of the guideline model with the knowledge representation formalism yields a clinical decision model that relies on the development of multiple information scenarios and the exploration of different clinical hypotheses.


2012 ◽  
Vol 605-607 ◽  
pp. 1547-1551
Author(s):  
Zhan Li Wang ◽  
Qian Liang ◽  
Bang Cheng Zhang

With the development of robot technology, massage robot has attracted fully attention, and the study about robot arm has been a growing interest in the area of massage robot. This article has put forward a new massage robot arm, which uses the chain as the main transfer mode by the requirements of the overall design massage of the robot arm. The design of big arm, shoulder joint, forearm, elbow joint and wrist are introduced. Based on the design requirements, we made some improvements with sprockets, ensuring transmission conditions and meeting the massage requirements. And finite element analysis for the designed arm, results show that the structure design can meet the requirements.


1990 ◽  
Vol 6 (02) ◽  
pp. 69-80
Author(s):  
H. S. Bong ◽  
William Hills ◽  
John B. Caldwell

The paper describes a method of incorporating knowledge and data of the production process into a concept design model in a way which provides a flexible and powerful structural design tool. Interactive graphics is shown to be a useful design aid when defining geometry and scantlings particularly when combined with a database of information on standardization, build methods and production technology. An effective method of assessing work content is presented in which man-hours are assessed for each phase in the construction process, that is, preparation, fabrication and erection. The total build cost, including labor, material and overhead, is used as the criterion in a series of studies which demonstrate the application of the method to concept design and which show the sensitivity of total cost to changes in various parameters of design and production.


Sign in / Sign up

Export Citation Format

Share Document