An Evaluation Grid Method System for Extracting Diverse User Requirements and Related Design Variables

2020 ◽  
Vol 2020.30 (0) ◽  
pp. 1403
Author(s):  
Mamiko SAKURAGI ◽  
Kento TANAKA ◽  
Rimpei YAMAGUCHI ◽  
Tomoya ISHIKAWA ◽  
Shuho YAMADA ◽  
...  
2021 ◽  
Vol 8 (2) ◽  
pp. 237-245
Author(s):  
Anwr M. Albaghdadi ◽  
Masri B. Baharom ◽  
Shaharin A. Sualiman

In this paper, a new configuration of Crank-Rocker (CR) model has been proposed by duplicating its mechanism. The method has been implemented to overcome vibration problem on a single-piston Crank-Rocker engine caused by system unbalance. The new method suggests combining conventional method of adding counterweights to reduce shaking forces and eliminating the inertial moments on system by implementing the new layout. A dynamic study of the new model is presented, then the objective function is derived and implemented to perform the optimization process. Related design variables and system constraints are introduced to determine attached counterweights optimized characteristics. For results validation, the simulation, dynamic analysis, and optimization process were conducted using ADAMS VIEW® software. The output results were presented and discussed to verify the validity of the suggested method. It was noticed that the method was very effective and has managed to reduce the total shaking forces by about 91%, shaking moment by about 66%; and the driving torque by 27%.


2019 ◽  
Vol 13 (4) ◽  
pp. 517-525
Author(s):  
Masato Inoue ◽  
Wataru Suzuki ◽  
◽  

To achieve a universal design that satisfies diverse user requirements associated with aging and internationalization, designers must make a decision based on diverse user requirements. Designers have generally incorporated average human physical characteristics in their designs. Thus, user limitations are critically important. Traditional design methods often regard engineering and product design as iterative processes based on point values. However, when user information is represented as a point value, the resulting product satisfies only that specific user group and does not necessarily satisfy diverse user groups. This study proposes a universal design method that obtains diversely ranged design solutions for user requirements. The proposed method defines diverse user requirements, design variables, and user characteristics as sets, which range in value. To represent user information accurately, users are classified into numerous groups using classification techniques. Design variables are divided into two types: control and noise. Control factors are designer-controllable variables that are based on design specifications. Noise factors are designer-uncontrollable variables representing user characteristics. To derive a ranged design solution set, designers clarify the relationship between performance and design variables. Ranged solutions satisfying required performance are derived for each group using all relational expressions and ranged variable values. The combinations of divided design variables that cannot satisfy the required performance are eliminated from the design proposal, and the narrowed range of design variables become ranged solutions. The ranged solutions are derived for each group, and the common range of design variables is the ranged solution for all users. This paper chooses the design problem of the strap height of a train as a case study of the proposed universal design method. In this case study, we consider diverse user requirements based on the variability of physical characteristics. This paper discusses the suitability of our proposed approach for obtaining ranged solutions that reflect the physical characteristics of diverse users.


Author(s):  
Madan Mohan Dabbeeru ◽  
Amitabha Mukerjee

Product portfolios need to present the widest coverage of user requirements with minimal product diversity. User requirements may vary along multiple performance measures, comprising the objective space, whereas the design variables constitute the design space, which is usually far higher in dimensionality. Here we consider the set of possible performances of interest to the user, and use multi-objective optimization to identify the non-domination or the pareto-front. The designs lying along this front are mapped to the design space; we show that these “good designs” are often restricted to a much lower-dimensional manifold, resulting in significant conceptual and computational efficiency. These non-dominated designs are then clustered in the design space in an unsupervised manner to obtain candidate product groupings which the designer may inspect to arrive at portfolio decisions. With help of dimensionality reduction techniques, we show how these clusters in low-dimensional manifolds embedded in the high-dimensional design space. We demonstrate this process on two different designs (springs and electric motors), involving both continuous and discrete design variables.


2019 ◽  
Vol 4 (4) ◽  
pp. 663-676 ◽  
Author(s):  
Andrew P. J. Stanley ◽  
Andrew Ning

Abstract. The wind farm layout optimization problem is notoriously difficult to solve because of the large number of design variables and extreme multimodality of the design space. Because of the multimodality of the space and the often discontinuous models used in wind farm modeling, the wind industry is heavily dependent on gradient-free techniques for wind farm layout optimization. Unfortunately, the computational expense required with these methods scales poorly with increasing numbers of variables. Thus, many companies and researchers have been limited in the size of wind farms they can optimize. To solve these issues, we present the boundary-grid parameterization. This parameterization uses only five variables to define the layout of a wind farm with any number of turbines. For a 100-turbine wind farm, we show that optimizing the five variables of the boundary-grid method produces wind farms that perform just as well as farms where the location of each turbine is optimized individually, which requires 200 design variables. Our presented method facilitates the study and both gradient-free and gradient-based optimization of large wind farms, something that has traditionally been less scalable with increasing numbers of design variables.


2019 ◽  
Author(s):  
Andrew P. J. Stanley ◽  
Andrew Ning

Abstract. The wind farm layout optimization problem is notoriously difficult to solve because of the large number of design variables and extreme multimodality of the design space. Because of the multimodality of the space and often discontinuous models used in wind farm modeling, the wind industry is heavily dependent on gradient-free techniques for wind farm layout optimization. Unfortunately, the computational expense required with these methods scales poorly with increasing numbers of variables. Thus, many companies and researchers have been limited in the size of wind farms they can optimize. To solve these issues, we present the boundary-grid parameterization. This parameterization uses only five variables to define the layout of a wind farm with any number of turbines. For a 100 turbine wind farm, we show that optimizing the five variables of the boundary-grid method produces wind farms that perform within 0.5 % of farms where the location of each turbine is optimized individually, which requires 200 design variables. Our presented method unlocks the ability to optimize and study large wind farms, something that has been mostly infeasible in the past.


Author(s):  
Tugrul Talaslioglu

In this study, a unified optimal design approach is proposed for the design of skeletal dome structure (SDS). Thus, this study has three objectivities, i) presenting the emergence of proposed design integrity, ii) applying the proposed optimal design approach for the design optimization geometrically nonlinear SDS with both ellipse and sphere-shaped forms considering both the shape, size and topology-related design variables, iii) determining the dominant design criteria in the design of SDS. In this framework, the design of SDS is optimized thereby minimizing its entire weight and joint displacements and maximizing its member forces at the same time. The design constraints are borrowed from the provisions of American Petroleum Institute (API RP2A-LRFD) specification. A multi-objective optimization algorithm (MOA) named Pareto Archived Genetic Algorithm (PAGA), as an optimization tool is integrated by an automatic dome generating tool. Therefore, the novelty of this study comes from being the first attempt to obtain the optimal design in a way of integrating both member and joint-related design constraints by the geometrically nonlinear structural analysis. Consequently, it is displayed that that the proposed optimal design approach facilitates to determine an appropriate optimal design through a tradeoff analysis for designers depending on their preferences. The design concepts concerned with buckling, axial stress, combination of axial & bending, and yielding have the higher dominant effects in the optimal design of SDS. Furthermore, it is also demonstrated that the inclusion of diagonal members into the design of SDS provides a reduction in the violation of dominant design constraints.


2020 ◽  
Vol 217 ◽  
pp. 02001
Author(s):  
Ting Wen ◽  
Yu Liu ◽  
Jin Wang ◽  
Wuxing Zheng ◽  
Teng Shao

In urban scale, solar energy utilization potential is closely related to residential density. Taking Xining City as an example, this paper explored how density of urban residential area affects solar energy utilization potential of urban housing. By changing density related design variables , including building layout, density rate, floor-site area ratio and the number of floors, 36 general models of residential areas with low, medium and high density are Abstracted. The results show that solar energy utilization potential of buildings varies greatly with different density related design variables. Comparison of a number of different scenarios reveals how density related variables affect solar energy utilization potential, based on which suggestions for optimization of solar energy potential for urban residential areas in their initial planning and design stages are proposed.


1967 ◽  
Author(s):  
GEORGE R. WHEATON ◽  
ALBERT ZAVALA ◽  
HAROLD P. VAN COTT

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