• Transactions of Materials Processing
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• v.16 no.4 s.94
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• pp.254-259
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• 2007

Dent resistance is an important characteristic to avoid damage on automotive outer panels. From a practical point of view, dents can be caused in a number of ways. Considering doors as an example, denting can occur from stone impacts or from the careless opening of an adjacently parked vehicle door. Denting can occur where the door surface is smooth and may not have sufficient curvature to resist dent. These exterior body parts are designed to improve dent resistance using a combination of work hardening and bake hardening. In brief, dent is affected by the shape of the parts and the material properties such as yield strength, strain and thickness. In this work, forming of door outer panel is investigated by Taguchi method. Main parameters are yield strength, thickness, blank size, blank holding force and so on. For the given value of design parameters, forming analysis of the eighteen cases are carried out according to L18 orthogonal array. After comparing the performance by simple conversion of simulation results into dent resistance, the final suggestion of the forming parameters is verified for the optimal improvement of dent resistance.

• Design & Manufacturing
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• v.14 no.1
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• pp.8-14
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• 2020

In general, auto parts production assembly line is assembled and produced by automatic mounting by an automated robot. In such a production site, quality problems such as misalignment of parts (doors, trunks, roofs, etc.) to be assembled with the vehicle body or collision between assembly robots and components are often caused. In order to solve such a problem, the quality of parts is manually inspected by using mechanical jig devices outside the automated production line. Automotive inspection technology is the most commonly used field of vision, which includes surface inspection such as mounting hole spacing and defect detection, body panel dents and bends. It is used for guiding, providing location information to the robot controller to adjust the robot's path to improve process productivity and manufacturing flexibility. The most difficult weighing and measuring technology is to calibrate the surface analysis and position and characteristics between parts by storing images of the part to be measured that enters the camera's field of view mounted on the side or top of the part. The problem of the machine vision device applied to the automobile production line is that the lighting conditions inside the factory are severely changed due to various weather changes such as morning-evening, rainy days and sunny days through the exterior window of the assembly production plant. In addition, since the material of the vehicle body parts is a steel sheet, the reflection of light is very severe, which causes a problem in that the quality of the captured image is greatly changed even with a small light change. In this study, the distance between the car body and the door part and the door are acquired by the measuring device combining the laser slit light source and the LED pattern light source. The result is transferred to the joint robot for assembling parts at the optimum position between parts, and the assembly is done at the optimal position by changing the angle and step.

• Korean Institute of Interior Design Journal
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• v.13 no.4
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• pp.37-44
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• 2004

Advancement in electronic technology has given office workers a new freedom, and a new meaning to workplace flexibility. Actually non territorial workplace has different space elements from general and conventional workplace in terns of interior design and architecture even organization management. The purpose of this study is on the establishment of an evaluation model for non territorial workplace that may be used, practically on the spot. For the establishment of non territorial workplace evaluation model, it is ahead of the study of the feature and the type of none territorial workplace and the research for existing office evaluation technique by Preiser and Vicher. And then the evaluation model for none territorial workplace which is composed three parts that is user's importance, provider's importance and user' satisfaction related fact of workplace. It is constructed by 6 factors which are physical, psychological, workplace environmental, communication, exterior environment, and space managing system therefore each factors has scrupulous elements therefore the total elements are 40. To make more confidence the evaluation model for non territorial workplace, it requires that study continually through the survey with the non territorial workplace evaluation model.

• Journal of Mechanical Science and Technology
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• v.18 no.11
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• pp.1909-1915
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• 2004

The hermetic rotary compressor is one of the most important components of an air conditioning system since it has a great effect on both the performance and the noise and vibration of the system. Noise and vibration occurs due to gas pulsation during the compression process and to unbalanced dynamic force. In order to reduce noise and vibration, it is necessary to identify their sources and transmission path and effectively control them. Many approaches have been tried in order to identify the noise transmission path of a compressor. However, identification has proven to be difficult since the characteristics of compressor noise are complicated due to the interaction of the compressor parts and gas pulsation. In this study, the statistical energy analysis has been used to trace the energy flow in the compressor and to identify the transmission paths from the noise source to the exterior sound field.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.65-67
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• 2011

It is necessary to the development of the best maintenance system for applying the long-term maintenance plan using the cost breakdown structure in the educational facilities. This study developed the cost breakdown structure for the best maintenance system using the delphi method. For the convenience of maintenance, the maintenance cost breakdown structures are separated into building exterior wall, building inside wall, electric installation, heating installation and outdoor facilities. And these results atomized in each parts. And this study constructed the cost breakdown structure to maintenance's practicality and effectiveness through the expert analysis.

• International Journal of Railway
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• v.4 no.3
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• pp.70-73
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• 2011

Controlling the exterior and interior noise emission has become an important issue in the research and development of high speed trains. As the operating speed of the train increases, the noise emission characteristics are expected to deviate from that of the existing trains due to several changes in the basic train layout. For train speed in excess of 350 km/h in particular, the aerodynamic noise component starts to exceed the structure-borne noise component, and even an incremental speed increase is accompanied by a rapid elevation in the noise level. The present study presents an engineering approach for predicting the aerodynamic noise level at the design stage for high speed trains. The experimental noise measurements from test run of Korean high speed train under development are presented as a partial validation of the proposed approach. While the overall aerodynamic noise can be cast in a single power law relationship against the train speed, different parts of the train show power law relationships unique to each component.

• Journal of the Korea Furniture Society
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• v.24 no.3
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• pp.302-308
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• 2013

To collection of field data for development of maintenance manual of Han-ok, we investigated defects which occurred in members of Han-ok by field investigation. The noticeable defects were wood cracks, gaps that developed between wood pillar and wall or wood window frame and tenon joints. The most common biological defect was blue stain which was created in log. The mold generation was observed on exterior wood and wall which get wet by precipitation. The gaps between members of Han-ok pointed out as defect that is urgently improved by residents of Han-ok. The reason is mainly due to poor of insulation in winter by bad confidentiality. The maintenance work of defect such as gap was conducted personally. As a result, the repair parts were ugly for unfamiliar repair work.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.342-348
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• 1998

The purpose of this paper is to extract fast DEM (Digital Elevation Model) using satellite images. DEM extraction consists of three parts. First part is the modeling of satellite position and attitude, second part is the matching of two images to find corresponding poults of them and third part is to calculate the elevation of each point by using the result of the first and second part. The position and attitude modeling of satellite is processed by using GCPs. A area based matching method is used to find corresponding points between the stereo satellite images. In the DEM generation system, this procedure holds most of a processing time, therefore a new fast matching algorithm is proposed to reduce the time for matching. The elevation of each point is calculated using the exterior orientation obtained from modeling and disparity from matching. In this paper, the SPOT satellite images, level IA 6000 $\times$6000 panchromatic images are used to extract DEM. The experiment result shows the possibility of fast DEM. extraction with the satellite images.

• Journal of Welding and Joining
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• v.31 no.4
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• pp.23-27
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• 2013

Laser heat source was used for automotive interior and exterior parts to reduce weights. Typically, 900's nm wavelength of laser has been widely used for polymer joining, however, the transmittance of the laser beam thorough clear polymers such as PMMA or PC has been an issue to overcome. To solve this issue, 1,940nm laser was applied on the clear polymer for the better absorption and 900nm laser beam was used for main laser for the joining. Conventional Gaussian or Elliptical heat source approximation has limitation in polymer which had deeper skin depth where major laser beam absorbs. To accurately simulate the physical laser beam absorption and joining optical properties were experimentally measured for the computer FEM simulation. The simulation results showed close correlation between theoretical and experimental results. The developed laser process is expected to increase productivity and gap closing which can cause failure of joining in laser material processing.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.269-276
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• 2004

Deterioration analysis was performed on carbody and bogies of a shunting locomotive, which has been used for shunting works in steel making processes. In this investigation, various types of technical evaluation methods for the locomotive were employed to assess the current deterioration status. Corrosion test and nondestructive evaluation (NDE) techniques were employed to demonstrate the wear status of the carbody and bogie parts in the locomotive. Since the locomotive has been working under corrosive environment, the corrosion tests with x-ray analysis for exterior part of the locomotive were conducted to examine the evolution of corrosion reaction, and NDE techniques such as ultrasonic testing, magnetic particle testing, and x-ray radiography, were conducted on the carbody and bogies to inspect any possible inherent and/or in-service flaws. In this paper, the degree of deterioration in a shunting locomotive has been presented based on the analysis results.