• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.70-76
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• 2003

An experimental study was performed to understand the heat transfer and fluid dynamic characteristics of Sub-Cooled Hybrid Condenser (SCHC), which conventional condenser and receiver dryer are integrated into. SCHC also employs a sub-cooled refrigerant passages at the end of the condenser in order to supply perfect liquid refrigerant to the expansion unit. Throughout the present study, it was found that the developed SCHC increases in the degree of sub-cooling by 10~100% compared to conventional condenser. The excessive sub-cooling has improved the cooling performance by 10%, and that leads reduction in evaporator outlet air temperature by $1.5^{\circ}C$. Also found through the study is that the refrigerant pressure drop across SCHC is fairly increased due to insertion of the desiccant cartridge in the receiver tank which is composed of zeolite, filter and supporter plate.

• Journal of environmental and Sanitary engineering
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• v.14 no.2
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• pp.1-7
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• 1999

In the tungsten industry as light source material, tungsten filament which used as light source material ould form after molybdenum wire which used as the center supporter for coil shape tungsten wire was removed. The purpose of this study is to develop new process named "hydrogen peroxide dissolution method". This process uses hydrogen peroxide, which is harmless to human body and oxidize molybdenum wire selectively. The results were as follows:1. The dissolution of molybdenum wire was proportion to a solution and contact surface of molybdenum wire. 2. The optimum $H_2O_2/H_2O$ were 1:0.5 ~ 1:1.75. 3. The time of dissolution was 65~70 minutes, and the PCS of sample were 20,800 PCS(1,820g). 4. Total cost($H_2O_2$, catalyst) was ￦19,088.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.660-663
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• 2001

There is a mechanical device between the superstructure and substructure of a bridge, which transmit vertical load of superstructure to the substructure and absorb horizontal displacement of super structure due to thermal, dynamic, load, etc. In order to meet two requirements at once, the structure of roller between plates is widely used, and this roller between plates is widely used, and this roller shoe system is known to have smaller horizontal movement resistance than any other type of bridge shoe. In this study, rolling friction resistance characteristics of roller-plate friction system is investigated according to roller dimension, vertical load, hardness and roughness of roller and plate. On the base of the results, the rolling friction resistance of large scale roller shoe is evaluated using model experiment.

• Journal of Families and Better Life
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• v.35 no.1
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• pp.59-69
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• 2017

The purpose of the study was to investigate the roles of child group home directors and their experiences with children. The study utilised the interpretive science paradigm and individual in-depth interviews for data collection. The qualitative theme analysis method explored the experiences of child group home directors. The participants, seven group home directors in the metropolitan area of Seoul, explained their multiple roles such as protector, nurturer, discipliner, mediator, and supporter of children while recognizing dysfunctions of children's family of origin. Participants claimed that the specialization of the child group home and the professionalism of its staffs were needed in order to improve the quality of child welfare. The results of this study might contribute to practical suggestions for group home professionals.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.451-460
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• 2003

In this paper, high speed fiber optic sensor weigh-in motion (WIM) system is proposed. Bragg gratings which have several advantages such as good reproducibility and good multiplicity compare to other optical fiber sensors are used for the system. Fabry-Perot filter for the signal process, which cannot be used in the high speed measurement because of the limitation in fast operation of PZT, is excluded. A new signal processing system which employs bandwidth filter is proposed and bridge type new sensor package design is also proposed. Design of the mold supporter is modified to round shape and then supporting points do not change. The data from the fiber sensors show identical and linear behavior to the axle weight. The proposed fiber optic WIM system is tested in the laboratory and experimented with actual trucks. The new concept of calibration is introduced and calculated by the experiments. The calibrated weight data show good approximations to real axial weights regardless the velocities of the truck.

• Journal of KSNVE
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• v.3 no.1
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• pp.65-75
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• 1993

In this study, we identify the structural dynamic characteristics of the rigid body suspension system of waching machine containing rotating system, and consider the methods for the reduction of noise and vibration due to the structural problems. The structural dynamic characteristics of the suspension system have been studied by the computer simulation, in which the commercial software package, "DYMES(Dynamics of Mechanical System)" is used. The behaviour of the supporter by the rotating system has been parametrically studied by computer simulation, and the force and torque which are transferred to the fixed body through the suspension bar also has been calculated. The possibility to decide the position and the stability of the rigid body suspension system for waching machine is demonstrated based on various simulation results.n results.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1950-1953
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• 1996

A $1\;{\times}\;4$ micro mirror array is designed and fabricated. In contrast to other micro mirrors which utilize torsional flexure hinges or cantilevers for restoring torque and supporting purpose, we have placed a substrate hinge structure under each mirror. Each micro mirror consists of address electrode, substrate hinge consisting of pin and staple, supporter post, and mirror plate. Electrical connection between mirror plate and ground electrode is established by substrate hinge. Mirror undergoes a rotational motion due to electrostatic force when voltage difference is applied between address electrode and mirror plate. Micro mirrors with two different types of staple shape and two different pin sizes are designed and fabricated. Each mirror is designed to have ${\pm}\;10^{\circ}$ of deflection angle and have $100\;{\times}\;110\;{\mu}m^2$ of size.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.766-769
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• 2002

We have seen the effects of hole-injection buffer layer in organic light-emitting diodes using copper phthalocyanine(CuPc), poly(vinylcarbazole)(PVK), and Poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate)(PEDOT:PSS) in a device structure of ITO/buffer/TPD/$Alq_3$/Al. Polymer PVK and PEDOT:PSS buffer layer was made using spin casting method and the CuPc layer was made using thermal evaporation. Current-voltage characteristics, luminance-voltage characteristics and efficiency of device were measured at room temperature with a thickness variation of buffer layer. We have obtained an improvement of the external quantum efficiency by a factor of two, four, and two and half when the CuPc, PVK, and PEDOT:PSS buffer layer are used, respectively. The enhancement of the efficiency is attributed to the improved balance of holes and elelctrons due to the use of hole-injection buffer layer. The CuPc and PEDOT:PSS layer functions as a hole-injection supporter and the PVK layer as a hole-blocking one.

• Journal of the Korea Furniture Society
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• v.21 no.3
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• pp.248-252
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• 2010

This study is carried out to introduce the concept of Kagome structure as the new trial for the furniture design and the feasibility of its utilization in furniture industry. Kagome means originally the two dimensional bamboo-basket woven pattern that is composed of interlaced triangles whose lattice points each have four neighboring points, which was used in traditional bamboo craft design like 'Jukbuin(bamboo-wife)'. Its unique truss structure has been widely used by many kinds of the domain of science and engineering in mechanical and architectural industry with some merits, i,e, material utilization efficiency and robust strength. Here we tried to introduce two dimensional and three dimensional form of Kagome which are supposed to be a furniture design elements. Authors think these Kagome design could be realized with domestic lumber of inferior properties. Both of them would be used as a decorative element or mechanical supporter in furniture design.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.5
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• pp.601-608
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• 2007

To meet demand of big capacity and high speed rotation for washing machine, more stress from bending and twisting are complexly loaded onto the shaft supporting the horizontal drum, causing problems in fracture strength and fatigue life. Shafting system is mainly divided into flange and shaft. Flange is located between the drum and shaft, transferring power from the shaft to drum, and acting as a supporter of the back of the drum. Because section of flange has various design factors according to configuration of flange, the optimum conditions can’t be easily determined. Using a design of experiment (DOE), this study was performed investigating the interaction effect between factors as well as the main effect of the each design factor under bending and twist and proposed optimum condition using center composition method among response surface derived from regression equation of simulation-based DOE.