• Korean Journal of Construction Engineering and Management
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• v.10 no.5
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• pp.76-84
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• 2009

Korea's construction industry experienced no difficulty managing the costs of finishing work items in the apartment housing field thanks to the uniform specification and the standardized costs of finishing work items. Finishing work items have continuously become more high class and differentiated, which has caused the costs of finishing work items to rise. This study identified problems with the cost management when planning finishing work items and choosing their alternatives based on the current process applied to the planning stage of finishing work items. It also found problems with the information management of finishing work items including design, cost, and work information that took place in bulk. Based on the identified problems, the design, cost and work information of finishing work items was integrated so that they could management the costs and information when planning finishing work items and selecting their alternatives. Then a cost-based information management process was suggested for finishing work items by improving each of the project cost management elements. Finally, an information model for finishing work items was built by studying the ways to integrate the information hierarchy and library of finishing work items.

• Transactions of Materials Processing
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• v.7 no.4
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• pp.393-399
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• 1998

For minimizing wall thickness thinning of circular shells, a new stamping technology, the deep draw-ing process combined with ironing is approached and investigated. The design requirements for the deep drawing shells are to keep the optimum wall thickness with max. 10 percent thickness thinning of the initial blank thickness, to make uniform thickness strain distribution for the wall of circular shell and to improve the shape accuracy for the roundness and concentricity. In order to check the validity and effectiveness of proposed work, a sample process design is applied to a circular shell needed for a 4multi-stepped deep drawing. Through experiments, the variations of the thickness strain distribution in each drawing process are observed. Also a series of experiments are performed to investigate optimum process variables such as the geometry of tooling, radius and drawing rate. In particular, the advantage of current approach with ironing is shown in contrast to the conventional deep drawing process. From the results of proposed method, the optimum value of process variables are obtained, which contribute more uniform thickness strain distribution and better quality in the drawn product.

• The Research Journal of the Costume Culture
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• v.25 no.4
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• pp.488-498
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• 2017

This research focuses on the condition of the coveralls that automobile maintenance workers wear. The objective of this survey is to conduct a thorough analysis on the quality of the coveralls and put forth suggestions for improving their quality. The research data were collected through interviews and the results are as follows. The participants in this research engage in a variety of types of maintenance work including oil changes and overall system checks and they usually wear extra-large-sized coveralls. The coveralls are generally worn during the winter for warmth and the company handles all purchasing and maintenance of the work clothes. Participants mentioned that certain parts of the clothes where they bend and stretch are cumbersome and areas around the knees and arms become easily tainted. They have also reported that although the coveralls are necessary, they are for the most part dissatisfied when it comes to the materials, design, and color. The participants have suggested that new coveralls would help to increase their work efficiency. As a result, it is concluded that the coveralls require much more development to meet the workers' needs and improvements need to be made on the functionality, aesthetics, and symbolic aspects of the design.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.335-338
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• 2010

A recent study for tracing the profiles of supersonic axisymmetric Minimum Length Nozzle with uniform and parallel flow at the exit section, the stagnation temperature is taken into account. The aim of this work is to add optimization algorithm to the supersonic nozzle design in order to get the optimum nozzle shape. The comparisons of the nozzle contours based on the method of characteristics are presented. The specific heats and their ratio vary with the stagnation temperature when this temperature of a perfect gas increases. An application is made for air in a supersonic nozzle.

• Journal of the Semiconductor & Display Technology
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• v.12 no.2
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• pp.19-25
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• 2013

Extrusion is one of the most important operations in the polymer-processing industry. Balancing the distribution of flow through a die to achieve a uniform velocity distribution is the primary objective and one of the most difficult tasks of extrusion die design. If the manifold in a coat-hanger die is not properly designed, the exit velocity distribution may be not uniform; this can affect the thickness across the width of the die. Yet, no procedure is known to optimize the coat hanger die with respect to an even velocity profile at the exit. While optimizing the exit velocity distribution, the constraint optimization used in this work with allowable pressure drop in the die; according to this constraint we can control the pressure in the die. The computational approach incorporates three-dimensional finite element simulations software STAR-CCM+. These simulations are used with numerical optimization to design polymer coat hanger dies with pressure drop, uniform velocity and temperature variation across the die exit.

• Nuclear Engineering and Technology
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• v.53 no.5
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• pp.1556-1568
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• 2021

The plate-type fuel assembly adopted in nuclear research reactor suffers from complicated effect induced by non-uniform irradiation, which might affect stress conditions, mechanical behaviors and thermal-hydraulic performance of the fuel assembly. This paper is the Part II work of a two-part study devoted to analyzing the complex unique mechanical deformation and thermal-hydraulic characteristics for the typical plate-type fuel assembly under irradiation effect, which is on the basis of developed and verified numerical thermal-fluid-structure coupling methodology under irradiation in Part I of this work. The mechanical deformation, thermal-hydraulic performance and Mises stress have been analyzed for the typical plate-type fuel assembly consisting of support plates under non-uniform irradiation. It was interesting to observe that: the plate-type fuel assembly including the fuel plates and support plates tended to bend towards the location with maximum fission rate; the hot spots in the fuel foil appeared at the location with maximum thickness increment; the maximum Mises stress of fuel foil was located at the adjacent location with the maximum plate thickness increment et al.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.106-113
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• 2013

Since the 1960's, diverse movements that oppose the uniform design tendency of modernism appears in Italy. Especially, Gaetano Pesce, who opposed uniformity and standardization that are based on mass production system, had interests in making unique product, not an identical product, while accepting modern production technology. Therefore, the purpose of this study is to comprehend Pesce's design, which creates diversity by arranging contingent, non-predictive, and episodic aspects in creative and acceptance processes according to the intension of the designer within mass production system, as a non-representational characteristic, which appears widely in modern thought and the arts, and examine how it is materialized in detailed design work. The study methods are first examining non-representation with theoretical contemplation and dealing with the design philosophy of Pesce based on the examination. Next, in order to discover non-representational characteristics that appear in the work of Pesce, it examines from introducing worker's creativity, user's possibility of choice, openness in the working process, and the aspects of researching materials. And a specific application method will be drawn through case analysis centered on furniture design. Gaetano Pesce's design that denies the world of representation based on the sameness comes to possess non-representational characteristics that acknowledge contingency and ceaselessly create difference by intentionally arranging during the working process.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.9
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• pp.995-1002
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• 2012

In a refrigerator, many food boxes are stored, so the flow of chilly air has very complicate stream paths inside the room of a refrigerator. Moreover, on some occasions, there is no flow of chilly air in a space due to blocking flow paths by food boxes, which is an important issue to be settled for improving the ability of food storage with fresh states. One of methods to solve this problem is to redesign the flow-pattern of chilly air to be uniform flow inside room, if possible. In this work, we have tried to design the duct-structure for the uniform flow of a chilly air using a FE-analysis method. And we conducted real commercial tests using a refrigerator having the redesigned duct. The results showed that good agreements with general requirements.

• Korean Journal of Computational Design and Engineering
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• v.4 no.1
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• pp.12-18
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• 1999

A deformable non-Uniform Rational B-Spline (NURBS) based volume is programed for the force reflecting exoskeleton haptic device. In this work, a direct free form deformation (DFFD) technique is applied for the realistic manipulation. In order to implement the real-time deformation, a nodal mapping technique is used to connect points on the virtual object with the NURBS volume. This geometric modeling technique is ideally incorporated with the force reflecting haptic device as a virtual interface. The results in this work introduce details for the complete set-up for the realistic virtual clay modeling task with force feedback. The force reflecting exoskeleton haptic manipulator, coupled with a supporting PUMA 560 manipulator and the virtual clay model are integrated with the graphics display, and results show that the force feedback from the realistic physically based virtual environment can greately enhance the sense of immersion.

• Steel and Composite Structures
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• v.42 no.3
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• pp.375-388
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• 2022

In this work, limit elastic speed analysis of functionally graded porous rotating disks has been reported. The work proposes an effective approach for modeling the mechanical properties of a porous functionally graded rotating disk. Four different types of porosity models namely: uniform, symmetric, inner maximum, and outer maximum distribution are considered. The approach used is the variational principle, and the solution has been achieved using Galerkin's error minimization theory. The study aims to investigate the effect of grading indices, aspect ratio, porosity volume fraction, and porosity types on limit angular speed for uniform and variable disk geometries of constant mass. To validate the current study, finite element analysis has been used, and there is good agreement between the two methods. The study yielded a decrease in limit speed as grading indices and aspect ratio increase. The porosity volume fraction is found to be more significant than the aspect ratio effect. The research demonstrates a range of operable speeds for porous and non-porous disk profiles that can be used in industries as design data. The results show a significant increase in limit speed for an exponential disk when compared to other disk profiles, and thus, the study demonstrates a range of FG-based structures for applications in industries that will not only save material (lightweight structures) but also improve overall performance.