• Journal of Korean Institute of Industrial Engineers
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• v.30 no.3
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• pp.190-196
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• 2004

In this paper, we address a layout design problem, PTL[3], for determining an optimal 3-class-based dedicated linear storage layout in a class of unit load storage systems. Our objective is to minimize the expected single command travel time. We analyze PTL[3] to derive a fundamental property that an optimal solution to PTL[3] is one of the partitions based on the PAI(product activity index)-nonincreasing ordering. Using the property and partial enumeration, we construct an efficient exact algorithm with O $(n\;{\lceil}\;log\;n\;{\rceil}\;)$ for solving PTL[3].

• Culinary science and hospitality research
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• v.9 no.2
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• pp.98-114
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• 2003

This paper is written to analyze systematically the varieties of informations about cooking stream procedure on the basis of the basic theory of installation and arrangement such as SLP(Systemic Layout Planning) and to deduce the plan for the device, installation and arrangement suitable to cooking stream procedure. Through the substantial improvement in the modeling of hotel L, the optimization of the capacity of installation and arrangement, and the reduction of food resource stream and its movement and through the analysis of cooking stream procedure by disposing and dividing the main kitchen into three individual ones, the improvement of productivity in comprehensive cookery such as the specialization and equalization of cooking procedure and improvement effect of the price-reduction. Moreover, as for the problem of arrangement of installation, it was displayed that the effect went up to twice through the flexible production-related systems such as the improvement of arrangement, reduction of cooking preparation time, the standardization of cookery.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.4
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• pp.43-49
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• 2004

The production parts have required multiple processes such as drawing, piercing, blanking and notching etc. are performed with a high production rates in progressive die. In order to prevent the defects of process result, the optimization of strip process layout design, die design, die making, and tryout etc. are needed. According to these factors of die development process, it has been required that the theory and practice of metal working process and its phenomena, die structure, machining conditions for die making, die materials, heat treatment of die components, processing know-how and so on. In this study, we designed and analyzed die components through the carrying out of upper relevant matters also simulated the strip process layout of multiple stage drawing by DEFORM. Especially the result of tryout and its analysis became to the feature of this study with a system of PDDC(Progressive Die design by computer).

• Journal of Korean Institute of Industrial Engineers
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• v.18 no.2
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• pp.109-121
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• 1992

In this paper, we address a layout design problem for determining a K-class-based dedicated storage layout in an automated storage retrieval system. K-class-based dedicated storage employs K zones in which lots from a class of products are stored randomly. Zones form a partition of storage locations. Our objective function is to minimize the expected single command travel time, which is expressed as a set function of space requirements for zones, average demand rates from classes, and one-way travel times from the pickup/deposit station to locations. We construct a heuristic algorithm based on analytical results and a local search method, the methodology deveolped can be used with easily-available data by warehouse planners to improve the throughput capacity of a conventional warehouse as well as an AS/RS.

• Journal of Korea Multimedia Society
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• v.11 no.12
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• pp.1758-1764
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• 2008

In this paper, we propose query restructure method which realizes not only to present the result from database in Web page but also to adapt user's browsing environments. Recently, wireless PDA (Personal Digital Assistant) and portable phone and terminals equipped with Web browser become very popular. Various browsers would be required to create the HTML which adapt to the user's browsing environment. We propose an adaptive data presentation system which is an extension of SQL which creates HTML pages dynamically adapting to the size of screen. In our proposed method, the three basic rules for the layout conversion are provided and applying these rules, an efficient layout conversion technique optimized to user environment is proposed. Moreover, we propose a standard for converting layouts and a layout optimization for adaptive conversion of layouts.

• Journal of Information Processing Systems
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• v.17 no.2
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• pp.271-283
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• 2021

When generating layout schemes, both the material usage and practicality of the cutting process should be considered. This paper presents a two-section algorithm for generating guillotine-cutting schemes of rectangular blanks. It simplifies the cutting process by allowing only one size of blanks to appear in any rectangular block. The algorithm uses an implicit enumeration and a linear programming optimal cutting scheme to maximize the material usage. The algorithm was tested on some benchmark problems in the literature, and compared with the three types of layout scheme algorithm. The experimental results show that the algorithm is effective both in computation time and in material usage.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.1
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• pp.9-21
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• 2018

Survivability of naval vessels is defined as the ability to perform functions and missions in a combat environment. Survivability has close relationship with the spatial layout of naval vessels. In order to maximize survivability, it must be considered from the early stage of design. However the existing concept of survivability was intended to be applied to unit vessels. So it was not suitable for assessment of spatial layout results at the early stage of design. In this paper, a simplified assessment method which can evaluate the spatial layout considering the survivability in the early stage of design has been proposed. For this, assessment layers were defined on survivability components such as susceptibility, vulnerability, and recoverability. Assessment layers of each component were overlapped to deduce a survivability layer of spatial layout alternatives. In addition, the proposed method and optimization algorithm were used to derive optimal spatial layout alternatives considering survivability.

• Computational Structural Engineering : An International Journal
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• v.1 no.1
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• pp.21-29
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• 2001

The general topology optimization can be considered as optimal material distribution. Such an approach can be unstable, unless composite materials are introduced. In this research, a nodal volume fraction method is used to obtain the optimum topology of continuum structures. This method is conducted from a composite material model composed of isotropic matter and spherical void. Because the appearance of the chessboard patterns makes the interpretation of the optimal material layout very difficult, this method contains a chessboard prevention strategy. In this research, several topology optimization problems are presented to demonstrate the validity of the present method and the recursive quadratic programming algorithm is used to solve the topology optimization problems.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.335-342
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• 2002

A continuum-based design sensitivity analysis (DSA) method fur non-shape problems is developed for geometrically nonlinear elastic structures. The non-shape problem is characterized by the design variables that are not associated with the domain of system like sizing, material property, loading, and so on. Total Lagrangian formulation with the Green-Lagrange strain and the second Piola-Kirchhoff stress is employed to describe the geometrically nonlinear structures. The spatial domain is discretized using the 4-node isoparametric plane stress/strain elements. The resulting nonlinear system is solved using the Newton-Raphson iterative method. To take advantage of the derived analytical sensitivity In topology optimization, a fast and efficient design sensitivity analysis method, adjoint variable method, is employed and the material property of each element is selected as non-shape design variable. Combining the design sensitivity analysis method and a gradient-based design optimization algorithm, an automated design optimization method is developed. The comparison of the analytical sensitivity with the finite difference results shows excellent agreement. Also application to the topology design optimization problem suggests a very good insight for the layout design.

• Journal of Korean Association for Spatial Structures
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• v.21 no.2
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• pp.89-97
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• 2021

This paper describes an adaptive hybrid evolutionary firefly algorithm for a topology optimization of truss structures. The truss topology optimization problems begins with a ground structure which is composed of all possible nodes and members. The optimization process aims to find the optimum layout of the truss members. The hybrid metaheuristics are then used to minimize the objective functions subjected to static or dynamic constraints. Several numerical examples are examined for the validity of the present method. The performance results are compared with those of other metaheuristic algorithms.