• 조명전기설비학회논문지
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• 제26권6호
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• pp.66-72
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• 2012

The main sources of energy consumption in warehouses are MHE(Material Handling Equipment), HVAC(Heating, Ventilating and Air Conditioning) and Lighting. Warehouses in advanced countries raise energy efficiencies with energy consumption diagnosis, technology development and systematic management and improvements for MHE, HVAC and Illuminating, etc. They have managed illuminating system, air conditioning, motor driven system, air circulation method, dock facility, layout, AS/RS, conveyor system and battery management, etc. Ansong Pyeongtaek area investigation resulted that 43.9[%] of enterprises are managing partly energy consumption source. But the data resulted with not substantial management of energy consumption but passive management for only electric bill curtailment. Therefore through survey research & visiting interviews of some companies in Ansong Pyeongtaek area, we understood the status of energy consumption source management and proposed energy efficiency methods on the basis of that results.

• 대한조선학회 특별논문집
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• 대한조선학회 2017년도 특별논문집
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• pp.63-66
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• 2017

All passenger ships aboard more than 36 passengers are to be able to easily find escape routes when the escape way by fire with flame spread were onboard vessel (incl. Ferry, Passenger, Ro-pax, Inland Ferry) It should be impossible by ordinary emergency lights. The international Maritime Organization (IMO) gives special requirement for luminescent evaluation onboard test procedure and applicable location of low location lighting. In order to maintain the residual light source for a certain time in the low location lighting with a strip-shaped light source, the light source material must be sufficiently exposed to the light due to the proper placement of the escape route. The lighting arrangement influence how maintain low location lighting strip luminescent which measured onboard in connection with what elements are mainly sustain luminescent.

• Journal of Welding and Joining
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• 제18권3호
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• pp.76-82
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• 2000

In this study, three-dimensional heat flow in laser beam welding for deep penetration was analyzed by using F.E.M common code, and then the results were compared with the experimental data. The models for analysis are full penetration welds and are made at three different laser powers (6, 9.9, 4.5 kW) with two different welding speeds (5.8mm/s, 5mm/s). The characteristics of thermal absorption by the workpiece during deep penetration laser welding can be represented by a combination of line heat source through the workpiece and distributed heat source at the top surface due to the plasma plume above the top surface. This gives an insight into the way in which the beam interacts with the material being welded. The analyses performed with the combined heat source models show comparatively good agreement between the experimental and calculated melt temperature isotherm, i.e, the fusion zone boundary. The results are used to explain the "nail head" appearance of fusion zone, which is quite common in laser beam welds.eam welds.

• Structural Monitoring and Maintenance
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• 제1권1호
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• pp.69-87
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• 2014

A new output only modal analysis method is developed in this paper. This method uses continuous wavelet transform to modify a popular blind source separation algorithm, second order blind identification (SOBI). The wavelet modified SOBI (WMSOBI) method replaces original time domain signal with selected time-frequency domain wavelet coefficients, which overcomes the shortcomings of SOBI. Both numerical and experimental studies on bridge models are carried out when there are limited number of sensors. Identified modal properties from WMSOBI are analyzed and compared with fast Fourier transform (FFT), SOBI and eigensystem realization algorithm (ERA). The comparison shows WMSOBI can identify as many results as FFT and ERA. Further case study of structural health monitoring (SHM) on an arch bridge verifies the capability to detect damages by combining WMSOBI with incomplete flexibility difference method.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.609-611
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• 2008

Eddy current is usually generated in material with high conductivity by time-varying source such as AC current and also is induced in the moving source with relative velocity. The contactless magnetic brakes make use of the braking force from the eddy current generated by moving source and currently used for the secondary brakes of heavy trucks, buses and rail vehicles. This study aims to design the magnetization pattern of a permanent magnet type eddy current brake system to maximize the braking force. The analysis of the brake system is based on the two-dimensional finite element analysis. We use the sequential linear programming as the optimizer and the adjoint variable method for the sensitivity analysis.

• Transactions on Electrical and Electronic Materials
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• 제2권2호
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• pp.32-36
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• 2001

A new solid source for low temperature diffusion into silicon was developed. The source wafer consists of an “active” compound, which is sol-gel prepared phosphosilicate glass-ceramics containing 56% P$_2$O$\sub$5/, embedded in a skeletal foam-like, inert substrate. Phosphorus diffusion from the new solid sources at low temperatures (800-875$^{\circ}C$) produced reprodecible sheet resistances and shallow junctions. From a series of one hour doping runs, the life time of the phosphosilicate source was determined to be over 40 hours. The effective diffusion coefficient of phosphorus into silicon and the corresponding activation energy at 850$^{\circ}C$ were determined to be 7.5${\times}$10$\^$-15/ $\textrm{cm}^2$/sec and ∼3.9 eV, respectively.

• 반도체디스플레이기술학회지
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• 제19권3호
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• pp.19-22
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• 2020

The thermal evaporation source is used to prepare thin films by physical vapor deposition. Materials of metals, organic materials, were tested and explained for thermal evaporation experiments. The developed effusion cell performance depends on the type of deposition material, the size of the crucible, the performance of the reflector, etc. and the proper conditions were found by producing, comparing and analyzing several sets of effusion cell to quantitatively evaluate the performance of the cell. The effusion cell for thermal evaporation source is used to prepare thin films of Ag, Cu, Mg.

• 한국물환경학회지
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• 제31권5호
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• pp.576-582
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• 2015

In recently, the Korea government is concerning on non-point source pollution management to improve water quality. The objective of this paper is to investigate the improvement measurement for management of livestock wastes. As a result, we find that the National Pollution Source Survey is necessary to establish the unified database system with the Korea Statistics(KOSAT) in order to minimize the difference between relevant data. The investigation for environmental impact of livestock manure should be supported the designation of control areas and establishment of the technical guidelines including target material, monitoring site, standard method, etc. In addition, it should be followed by appropriate nutrient recycling and proper fertilizer usage based on social consultation and cost-benefit analysis.

• 자원리싸이클링
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• 제12권1호
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• pp.65-74
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• 2003

As new functional electronics are being developed fast, the commercialization rate of advanced battery as a power source proceeds rapidly. Lithium battery is satisfying the needs of high-energy source for its lightness and good electrochemical property. Especially lithium ion battery, adopted as a new power source for portable electronic equipments around the globe, has been mass-produced. Under the circumstance, the generation of lithium battery wastes is becoming a new environmental problem. In this paper, we are going to inspect technology developments for recycling of lithium battery wastes and scraps in domestic and foreign area, and to suggest how to treat domestic lithium battery wastes and scraps better.

• 대한기계학회논문집A
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• 제33권7호
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• pp.658-663
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• 2009

Eddy current is usually generated in the material with high conductivity by time-varying source such as AC current and also is induced by the moving source with relative velocity. The contactless magnetic brake makes use of the braking force from the eddy current generated by the moving source and currently used for the secondary brakes of heavy trucks, buses and rail vehicles. This study aims to design the magnetization pattern of the eddy current brake system of a permanent magnet type where the design aim is to maximize the braking force. The analysis of brake systems is based on the two-dimensional finite element analysis. We use the sequential linear programming as the optimizer and the adjoint variable method is applied for the sensitivity analysis.