• Korean Journal of Construction Engineering and Management
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• v.6 no.4 s.26
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• pp.101-112
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• 2005

Recently, a curtain wall construction is a exterior finishing components which is most used for shortening time in high-rise building as well as the class of key management factors in cost and schedule control. Also, it is recognized that an effective management for curtain wall process is a major subject to accomplish the project successfully. However, as the current management for curtain wall construction is focused on the construction stage, it makes problems such as errors in business performance, rework by mistakes and duplications, errors and omissions by ineffective information management and there has never been any efficient management from a view of the entire Curtain Wall Life-cycle process. Therefore, the aim of this study is to suggest a stage check point for process improvement in the curtain wall Life-cycle process through current curtain wall process analysis, and then to investigate the cause of waste factors using the Muda method from the Toyota Production System and extract the weighted effects of the waste factors using the analytical hierarchy process method. According to the result, Most of the inefficient factors happened in architectural design stage of the entire curtain wall Life-cycle process and my research identified that detail factors of them are a delay of decision making and an approval in changes, a deficit of engineering capacity and a delay of approval in architectural design drawings by owner, etc.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.854-862
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• 2016

As the demand for a clean energy to replace fossil fuel being depleted increases, hydrogen energy is considered as a promising candidate for future energy source. Water electrolysis which produces hydrogen has high energy efficiency and stability but still has a large overpotential for oxygen evolution reaction (OER). In this study, $Co_3O_4$ catalysts with different morphology were prepared by spray pyrolysis from solutions which contain Co precursor and various organic additives (urea, sucrose, and citric acid), followed by post heat treatment. For the catalysts synthesized, X-ray diffraction (XRD) measurements were performed to identify their crystal structure. Morphology and surface shape of the catalysts were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Surface area and pore volume were examined by nitrogen adsortpion & desorption tests and X-ray photoelectron spectroscopy (XPS) was conducted to confirm nitrogen doping. Linear sweep voltammetry (LSV) was carried out to investigate OER activity of $Co_3O_4$ catalysts. As a result, bare-$Co_3O_4$ which has high surface area and small particle size determined by spray pyrolysis showed high activity toward OER.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.27-34
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• 2016

Garlic has drawn attention as a food material for its anti-oxidative and anti-inflammatory properties as well as for prevention and treatment of cancer. In order to increase efficiency, various aging methods for garlic have been attempted. In particular, thermally processed garlic is known to have higher biological activities due to its various chemical changes during heat treatment. Therefore, in this study, we investigated the anti-oxidative effects of garlic extracts aged at low temperature ($60{\sim}70^{\circ}C$). In the results, 2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis (3-ethylbenzo-thiazoline-6-sulfonate) radical scavenging activities and ferric reducing ability of low temperature-aged garlic (LTAG) were similar to those of raw garlic. LTAG also showed decreased lipopolysaccharide (LPS)-induced production of reactive oxygen species, although there were not significant differences among samples. In addition, xanthine oxidase activity was inhibited by LTAG; the 15 days and $60^{\circ}C$ extract showed outstanding inhibition compared with the others. To understand the molecular mechanisms behind the anti-oxidative activity of LTAG, we performed quantitative real-time PCR analysis. The 30 days and $70^{\circ}C$ extract upregulated mRNA expression of antioxidant enzymes such as Cu/Zn-superoxide dismutase (SOD), Mn-SOD, glutathione peroxidase, and catalase in LPS-stimulated RAW 264.7 cells. This result indicates that LTAG can be a functional food as a nature antioxidant and antioxidant substance.

• Journal of the Korea Concrete Institute
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• v.25 no.3
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• pp.295-304
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• 2013

Ultra-High Performance Concrete (UHPC) has recently been one of the most active research fields in Korea as well as in foreign countries, because it can contribute to a longer life and economic efficiency of structures. Although precast-type UHPC fabricated in a factory is preferable in terms of quality control and reduction of construction period, there exist, even in the precast structure, some parts that need to be cast in-place such as the joints between precast segments. In the cast-in-place UHPC, however, it is probable that an optimum curing condition can hardly be realized in contrast to the factory production. In this study, therefore, the trend of compressive strength development of UHPC was experimentally investigated by assuming various inferior curing conditions that may be anticipated at a construction site. Concrete specimens were fabricated and cured under different conditions with the variables such as curing temperature, delay time before the initiation of curing, duration of curing time and moisture condition. The strengths were compared with those of the specimens cured by standard high temperature steam. Through the analysis of the test results, some minimum requirements for curing have been proposed that are required when the UHPC is cast in-place. It is expected, through this study, that practical use of UHPC in construction sites can be increased.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.1
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• pp.7-11
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• 2014

Recently, the buffer layers consisting of poly (3,4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT-PSS) are extensively used to improve power conversion efficiency (PCE) of organic solar cells. However, PEDOT-PSS is not suitable for mass production of organic solar cells due to its intrinsic acid and hygroscopic properties. Moreover, because of chemical reactions between indium tin oxide (ITO) layer and PEDOT-PSS layer, the interface is not stable. For these reasons, alternative materials such as $V_2O_5$ have been developed to be an effective buffer layer. In this work, we used $V_2O_5$/Ag/ITO multilayer structure for the anode buffer layer. With variation of thickness of Ag layer, we investigated the optical and electrical properties of $V_2O_5$/Ag/ITO multi-layer films. As a result, we found that the electrical properties were improved with increasing Ag thickness while optical transmittance decreases in visible wavelength region. From the calculation of figure of merit (FOM) which is used to evaluate proper structure for transparent of optoelectronic, $V_2O_5$/Ag/ITO multilayer electrode was optimized with 4 nm thick Ag layer in optical (88% in transmittance) and electrical ($4{\times}10^{-4}{\Omega}cm$) properties. This indicates that $V_2O_5$/Ag/ITO multilayer electrode could be a candidate for the anode of optoelectronic devices.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.231-237
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• 2016

This research was conducted in order to examine whether the Woodgrab short-wood logging method, most widely used logging method in Korea, is more favorable than other logging methods in terms of productivity and profitability. For the comparative purposes, whole-tree logging methods with cable yarding system using a swing yarder and a tower yarder were evaluated. The productivity and the profitability of the logging operations by the machine types on a L. kaempferi stand were estimated by simulating logging processes based on bucking patterns and the results were compared. As a result, the Woodgrab short-wood logging system showed the most favorable results in terms of skidding productivity and operating cost. On the contrary, the system was the least profitable among the three logging methods. Main reason is that while the system may be beneficial in terms of operation productivity, it is restricted to produce only short logs mainly for low quality raw materials such as pulp, bolts, etc. which are sold at cheap prices.

• Korean Journal of Social Welfare
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• v.68 no.4
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• pp.119-141
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• 2016

This study analyzed on the basis of the norms and experience the Seongnam youth dividend ordinance. Youth dividend pros in the normative dimension to understand in order to achieve social justice. Further, youth dividend can replace the existing policy. On the other hand, the opposite of youth dividend is pointed out that the policy is ambiguous without morally justifiable. Also it has been pointed out inefficiencies means. Youth dividend Pros empirical dimension is a social considerations measures, there is a need for innovation by the failure of existing measures. On the other hand, youth dividend opposed to target efficiency is low, and that the problem is often to the contents of the salary. Because both sides are too contrast, consensus is difficult, can be political point of view is a significant impact. The basic income is a new thought experiment for human self-realization. Therefore, the production social welfare policy personality is a different policy science. That is, it is a long-term care social policy that requires a holistic life support. In addition, a non-empirical policy that requires a material support for the substantial freedom. Therefore, it is necessary to understand the philosophical meaning than scientific evaluation of traditional policy aiming to realize autonomous life. Therefore, radio waves of basic income through the welfare politics and exercise is still important strategy.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.317-325
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• 2015

This paper attempts to present a review about simulation of different greenhouse parameters and energy supplying techniques by using building energy simulation, to find out the optimal solution for keeping greenhouse microclimate favorable for the crop production. The objectives of conducting this study were, to describe the various energy systems and techniques used for the greenhouse energy management and efficiency analysis of these technologies by using building energy simulation. We describe different models to understand the behavior of the energy saving technologies with respect to the resources available and different outside climatic conditions. We identified main features of the building energy simulation software, that enable users, to simulate hybrid agricultural building projects by using user defined parameters. At the end of the paper we draw some important concluding remarks on the basis of reviewing all the investigators contributions for the developments of simulation model of agricultural greenhouse energy management, using a building energy simulation software specifically TRNSYS. In conclusion, this paper provides information that TRNSYS have great potential for agricultural buildings energy simulation along with the renewable energy resources and energy saving techniques. This review paper provides aid to greenhouse researcher and energy planner for the future studies of greenhouses energy planning.

• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.10-17
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• 2018

POU (point of use) scrubbers were applied for the treatment of waste gases including PFCs (perfluorocompounds) exhausted from the CVD (chemical vapor deposition), etching, and cleaning processes of semiconductor and display manufacturing plant. The GWP (global warming potential) and atmosphere lifetime of PFCs are known to be a few thousands higher than that of $CO_2$, and extremely high temperature more than 3,000 K is required to thermally decompose PFCs. Therefore, POU gas scrubbers based on the thermal plasma technology were developed for the effective control of PFCs and industrial application of the technology. The thermal plasma technology encompasses the generation of powerful plasma via the optimization of the plasma torch, a highly stable power supply, and the matching technique between two components. In addition, the effective mixture of the high temperature plasma and waste gases was also necessary for the highly efficient abatement of PFCs. The purpose of this paper was to provide not only a useful technical information of the post-treatment process for the waste gas scrubbing but also a short perspective on R&D of POU plasma gas scrubbers.

• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.177-182
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• 2002

Drying process is very important for commercialization of velvet antlers. So far, artificial drying has mostly depended on experience of farmers resulting in low efficiency of drying, deterioration during drying, and contamination by dust and bacteria. Various drying techniques for high-quality production have currently been commercialized in some developed countries, and one of them is a drying technique using microwave. In this study, application of the technique using an electronic (microwave) oven for drying of velvet antler was investigated. The results of this study are as follows. 1. It was found that the drying period was significantly affected by cornification of velvet antlers. Accordingly, it can be assumed that the velvet antlers should partly be sliced to save drying period and required drying energy. 2. It was also found that the drying speed was changeable according to tempering period and even with same drying period. The tempering period should be controlled according to processing rate. 3. The results indicated that a repeated drying of 2-min drying and 3-min tempering is the most effective when a microwave oven was used. 4. The results also showed that the drying technique using microwave of electronic oven can be effectively used for drying of velvet antlers. 5. Only drying and tempering periods were examined in this study, however, ingredient change of deer antler after drying is necessary to be investigated in the future.