• Proceedings of the KSR Conference
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• 2002.10b
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• pp.870-875
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• 2002

The weight saving that results from the substitution of aluminum alloy for steel may be used to provide reduced energy consumption and labor cost due to simplified manufacturing process and improved vehicle performance. Because of these advantages, foreign advanced rolling stock manufacturing companies have been using aluminum alloy for bodyshell manufacturing. In this research, the comparison between FE analysis and actual load test results is performed for aluminum extrusion bodyshell, which is manufactured by Rotem Company. And the results show that the aluminum carbody structure satisfies the strength and stiffness requirements. Commercial FE analysis code and specially designed test equipment are utilized for the structural analysis and the static load test of bodyshell respectively.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.2
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• pp.79-86
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• 2020

In order to accommodate the increase in urban population due to government-led national planning and economic growth, many buildings such as houses and business building were supplied. Although the building law was revised and managed to manage the supplied buildings, for the sake of economic benefit, there have been buildings that are enlarged or reconstructed without declaring building permits. In order to manage these buildings, on-site surveys were conducted. but it has many personnel consumption. To solve this problem, a method of using a satellite image and a manned aircraft is utilized, but it is diseconomical and a renewal cycle is long. In addition, it is not utilized to the height, and although it is judged by the shading of the building, it has limitations that it must be calculated individually. In this study, height of the building was calculated by using the unmanned aerial vehicle with low personnel consumption, and the accuracy was verified by comparison with the building register and measured value. In this study, spatial information was constructed using a fast unmanned aerial vehicle with low manpower consumption and the building height was calculated based on this. The accuracy by comparing the calculated building height with the building register and the actual measurement.

• Wind and Structures
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• v.19 no.4
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• pp.405-420
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• 2014

This paper examines the nonlinear behaviour of corrugated steel plate shear walls under lateral pushover load. One of the innovations in these types of walls which have used in recent years is the use of the corrugated steel shear walls rather un-stiffness plates. In the last decades many experimental studies have been done on the on the corrugated steel shear walls. A finite element analysis that includes both material and geometric nonlinearities is employed for the investigation. A comparison is made between the behaviour of steel shear walls with sinusoidal corrugated plate and trapezoidal corrugated plate. The effects of parameters such as the thickness of the corrugated plate, the corrugation depth in the corrugated plates and the corrugation length of the infill of the corrugated plates, are investigated. The results of this study have demonstrated that in the wall with constant dimensions, the trapezoidal plates have higher energy dissipation, ductility and ultimate bearing than sinusoidal waves, while decreasing the steel material consumption.

• Journal of Hydrogen and New Energy
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• v.23 no.3
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• pp.264-273
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• 2012

In this paper, two types of integrated gasification combined cycle (IGCC) plants using either an air separation unit (ASU) or an ion transport membrane (ITM), which provide the oxygen required in the gasification process, were simulated and their thermodynamic performance was compared. Also, the influence of adopting a pre-combustion $CO_2$ capture in the downstream of the gasification process on the performance of the two systems was examined. The system using the ITM exhibits greater net power output than the system using the ASU. However, its net plant efficiency is slightly lower because of the additional fuel consumption required to operate the ITM at an appropriate operating temperature. This efficiency comparison is based on the assumption of a moderately high purity (95%) of the oxygen generated from the ASU. However, if the oxygen purity of the ASU is to be comparable to that of the ITM, which is over 99%, the ASU based IGCC system would exhibit a lower net efficiency than the ITM based system.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.4
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• pp.16-23
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• 2011

Since the first lighting light source was invented, lighting has turned into superior-quality lighting considering the amenity of occupants, and the characteristics of a light source has developed rapidly. So this research confirmed the lighting performance of a dimmer control system and an ON-OFF control system via the existing light source, and analyzed the basic lighting environment of Permanent Supplementary Artificial Lighting of Interiors(PSALI) through the physical comparison and evaluation of a LED lamp substituted for a fluorescent lamp used in a dimmer control system, showing that the lighting physical quantity characteristics of an ON-OFF control system and a dimmer control system are similar to each other and that they are effective in terms of energy saving. Besides, it was shown that introducing a LED light source to a dimmer control system improves lighting environments and largely reduces energy consumption.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.395-403
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• 2013

Fishing efficiency of the squid jigging vessel using the LED and metal halide fishing lamp combination was analyzed to reduce the cost for fishing operation utilizing the fishing light system for high degree of efficiency in the squid jigging fishery (one of the representative coastal and offshore fisheries in Korea). This study aims to improve the nature of existing LED lamps and to develop fan-shaped LED lights having 180W of power and ${\pm}45^{\circ}$ angle of light intensity distribution. The marine experiment for making a comparison of their fishing efficiency was tested by a 9.77 tons fishing vessel from Oct. through Dec. 2012. As a result, experimental fishing vessel showed slightly higher fishing efficiency than the average of metal halide lamp-equipped vessel and 20% energy savings. This means that the combination of LED and metal halide lamps would provide an efficient way to lower energy consumption while maintaining fishing efficiency.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.4
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• pp.234-240
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• 2010

In October 2009, the Ministry of Land Transport and Maritime Affairs noticed 'Environment-friendly housing construction standards and performance' to build energy saving environment-friendly housings (Green Homes) for the reduction of energy consumption and carbon dioxide emission. In this study, the $CO_2$ emissions were evaluated during the life cycle of the existing apartments which were built in 1980's and Green Home apartment. $LCCO_2$ was evaluated by dividing the life cycle into three stages which are construction, maintenance and destruction stage. $CO_2$ emission from the materials for improving insulation performance was estimated by Input-output analysis. As a result, in 40 year-life cycle of $84\;m^2$ apartment, 400.68 T-$CO_2$ was emitted from 1980's apartment, on the other hand 231.02 T-$CO_2$ was emitted from Green Home apartment.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.15 no.4
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• pp.46-54
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• 2019

In this study, the performance of a shell and tube heat exchanger (STHE) and welded plate heat exchanger (WPHE) was measured experimentally. The pass numbers of the STHE was changed by 1, 2 and 4. As a result, the WPHE showed 2.1 times higher heat exchange capacity than that of the STHE. In case of pressure drop, the STHE with 1 and 2 pass number has a lower pressure drop than the WPHE, while the STHE with 4 pass presented higher pressure drop than the WPHE. The performance index considering the heat exchange capacity and pump consumption power, showed in oder of STHE_Pass1 > STHE_Pass2 > W PHE > STHE_Pass4 under the same flow rate. Therefore, when the WPHE was designed optimally under same operating condition with STHE, the maintenance fee and space can be reduced effectively by using the WPHE.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.10
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• pp.4864-4882
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• 2016

In this work, we consider the optimization problem of minimizing energy consumption for real-time multicast over wireless multi-hop networks. Previously, a distributed primal-dual subgradient algorithm was used for finding a solution to the optimization problem. However, the traditional subgradient algorithms have drawbacks in terms of i) sensitivity to iteration parameters; ii) need for saving previous iteration results for computing the optimization results at the current iteration. To overcome these drawbacks, using a joint network coding and scheduling optimization framework, we propose a novel distributed primal-dual Random Deflected Subgradient (RDS) algorithm for solving the optimization problem. Furthermore, we derive the corresponding recursive formulas for the proposed RDS algorithm, which are useful for practical applications. In comparison with the traditional subgradient algorithms, the illustrated performance results show that the proposed RDS algorithm can achieve an improved optimal solution. Moreover, the proposed algorithm is stable and robust against the choice of parameter values used in the algorithm.

• Membrane Journal
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• v.33 no.2
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• pp.70-76
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• 2023

Heavy water (D₂O) can induce various biochemical changes in comparison with light water (H₂O). In order to reduce excessive energy consumption, which is a disadvantage of the existing separation process, we conduct the forward osmosis with electrospun polyamide membranes. NaCl and phosphoric acid were used as draw solutions. FT-IR spectroscopy was used to quantify the concentration of heavy water. It was observed that phosphoric acid could concentrate heavy water through a forward osmosis process and its special interaction with hydrogen/deuterium (H/D) was spectrophotometrically confirmed.