• Journal of Ceramic Processing Research
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• v.20 no.5
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• pp.484-489
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• 2019

VO2 is an attractive candidate as a transition metal oxide switching material as a selection device for reduction of sneak-path current. We demonstrate deposition of nanoscale VO2 thin films via thermal atomic layer deposition (ALD) with H2O reactant. Using this method, we demonstrate VO2 thin films with high-quality characteristics, including crystallinity, reproducibility using X-ray diffraction, and X-ray photoelectron spectroscopy measurement. We also present a method that can increase uniformity and thin film quality by splitting the pulse cycle into two using scanning electron microscope measurement. We demonstrate an ON / OFF ratio of about 40, which is caused by metal insulator transition (MIT) of VO2 thin film. ALD-deposited VO2 films with high film uniformity can be applied to next-generation nonvolatile memory devices with high density due to their metal-insulator transition characteristic with high current density, fast switching speed, and high ON / OFF ratio.

• Journal of Families and Better Life
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• v.10 no.1 s.19
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• pp.75-94
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• 1992

The purpose of this study was to provide for the appropriate conflict management strategies to employed wives by investigation casual relations of conflict, resources, home management behavior and managerial satisfaction by applying a system's approach. The data were collected through the questionnaire whose respondent were 388 employed wives. The data were analyzed by various statistical methods such as Frequency, Percentage, ANOVA, F-test, T-test, Pearsons' correlation analysis, Multiple Regression analysis, Path analysys. The results of this study are as follows : 1) Input variables, throughput variables, output variables had differences significantly according to the family life cycle. The employed wives' families which are former term of the family life cycle used more appropriate conflict management strategies than latter term of FLC. That is, the employed wives' families which are former term of FLC had more abundant resources such as cohesive power of family, interaction with relatives, social support, had higher planning score, used more frequent structural management strategies. But, the managerial satisfaction had no differences. 2) For the relation of input variables and throughput variables, the more resources, the lower conflict is the higher planning, implementing score, structural management score. For the relation of throughput variables, the higher planning, implementing, structural management score is the higher managerial satisfaction score. For the relation of input variables and output variables, the more resources, the lower conflict is the higher managerial satisfaction, besides objective and material resource, subjective and psychological resource had influence. 4) among all variables affecting the managerial satisfaction, the commition of housework, cohesive power of family, wives' occupational level had indirect effect on managerial satisfaction through structural managemenet. Only the income had direct effect on managerial satisfaction.

• Journal of Korea Technology Innovation Society
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• v.15 no.3
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• pp.500-532
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• 2012

This study analyzed the technology innovation strategies of knowledge-based companies in the semiconductor IP industry. The theoretical approaches of this study are to i) the creation, protection and utilization of knowledge and innovation, ii) value creation from innovation, iii) modularity, timing of market entry, and the emergence and competition of standard (dominant design). Based on the theoretical analysis, I presented exploratory research hypotheses. Ultimately, this study examined the proposed hypotheses by conducting case studies on the technology innovation strategy of two leading knowledge-based companies in the semiconductor IP industry: ARM and INTEL. First, knowledge-based companies entering in the early stage of the technology cycle select the vertically-integrated technology strategy because of lower access to complementary knowledge assets, and maintain the vertically-integrated technology strategy despite the environmental change-driven differentiation of industry's value chain. Second, knowledge-based companies entering in the later stage of the technology cycle prefer the contract-based technology strategy because of its increased accessibility to complementary knowledge assets, and choose a different path of innovation strategies depending on whether their asset has the feature of discontinuity or not.

• Resources Recycling
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• v.11 no.4
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• pp.3-10
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• 2002

The characteristics of dry and wet milled powder prepared by 1 cycle OREOX (oxidation and reduction of oxide fuels) treatment were investigated using the simulated spent fuel pellet. Sintered pellets simulating spent nuclear fuel burned in reactor were fabricated from $UO_2$ powder using as a starting material in fabrication of nuclear fuel. The 1 cycle OREOX-treated powder was prepared by only one path of oxidation md reduction of the simulated pellet. Powder having average particle size of less than 1 $\mu\textrm{m}$ could be easily obtained by dry milling, but not be achieved by wet milling. And, specific surface area of dry milled pow-der was higher than that of wet milled powder. Dry milled powder formed loose agglomerate, while wet milled powder showed the shape of irregular and angular particles. Dry milled powder provided higher green density, resulting in higher sintered density of higher than 95% TD and average grain size of larger than 8 $\mu\textrm{m}$ satisfying the standard specification of sintered pellets.

• Journal of Korean Society of Rural Planning
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• v.18 no.3
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• pp.149-164
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• 2012

The purpose of the present study is to construct a rural development strategy from the nexus between spatial changes in specialized crops and suitable cultivation area of the crops. This paper pays particular attention to identify product life cycle of specialized crops in rural areas and estimate the impact of climate change on alterations in spatial distribution of the crops. In order to do so, first of all, this study applies multi-level model (Random coefficient model) to estimate the regional coefficient of five orchard crops. It utilizes the data 1995 to 2010 Korea Agricultural Census. Futhermore, it also adopts overlay analysis by ArcGIS to identify the development path of the crops and the relationship with climate change. Based on the results, it suggests a mechanism activating regional agriculture. The findings propose re-searching and relocating specialized regions of the crops. Especially, it proves each rural area can drive the new agricultural strategy to strengthen regional agriculture by estimating the relationship between development of specialized crops and suitable cultivation areas. For instance, shifting specialized crops in particular regions and enriching genetic or species varieties can be primary measures and it will contribute to improve the reliable base for income sources in the rural communities. This paper also offers specific policy implications regarding rural development plans in response to crops' life cycle and climate changes.

• Nuclear Engineering and Technology
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• v.45 no.4
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• pp.427-438
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• 2013

In this paper we discuss spent fuel management options in the Republic of Korea (ROK) from two interrelated perspectives: Centralized dry cask storage and spent fuel pyroprocessing and burning in sodium fast reactors (SFRs). We argue that the ROK will run out of space for at-reactors spent fuel storage by about the year 2030 and will thus need to transition centralized dry cask storage. Pyroprocessing plant capacity, even if approved and successfully licensed and constructed by that time, will not suffice to handle all the spent fuel discharged annually. Hence centralized dry cask storage will be required even if the pyroprocessing option is successfully developed by 2030. Pyroprocessing is but an enabling technology on the path leading to fissile material recycling and burning in future SFRs. In this regard we discuss two SFR options under development in the U.S.: the Super Prism and the Travelling Wave Reactor (TWR). We note that the U.S. is further along in reactor development than the ROK. The ROK though has acquired more experience, recently in investigating fuel recycling options for SFRs. We thus call for two complementary joint R&D project to be conducted by U.S. and ROK scientists. One leading to the development of a demonstration centralized away-fromreactors spent fuel storage facility. The other involve further R&D on a combined SFR-fuel cycle complex based on the reactor and fuel cycle options discussed in the paper.

• Korean Journal of Labor Studies
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• v.24 no.1
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• pp.29-64
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• 2018

This paper reviews the dynamics of growth and decline of Democratic Labor Union(Minju-nojo) Movement from the perspective of the conflicts among the industrial relations actors on the institutional incorporation of KCTU, a transformation of industrial relations institutes, and labor flexecurity in the change of political opportunity. The negotiations for the institutional incorporation of KCTU concluded in the 1997-98 labor laws. Since 1998, the conflicts and the compromises on the change of 1997-98 labor laws has continued. It was a kind of games for the transformation of the institutions of industrial relations and labor flexcurity. But the 1997-98 labor laws has shown the path-dependency. Since 2008, a cycle of the movement has entered a decline stage. The decline of Democratic Labor Union Movement came from the institutionalization of the movement, the change of political opportunity, and a generational change of 1987 cohorts group which has been the center of the movement.

• Geomechanics and Engineering
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• v.24 no.6
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• pp.519-529
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• 2021

In coal mining activities, the abutment stress of the coal has to undergo cyclic loading and unloading, affecting the strength and seepage characteristics of coal; additionally, it can cause dynamic disasters, posing a major challenge for the safety of coal mine production. To improve the understanding of the dynamic disaster mechanism of gas outburst and rock burst coupling, triaxial devices are applied to axial pressure cyclic loading-unloading tests under different axial stress peaks and different pore pressures. The existing empirical formula is use to perform a non-linear regression fitting on the relationship between stress and permeability, and the damage rate of permeability is introduced to analyze the change in permeability. The results show that the permeability curve obtained had "memory", and the peak stress was lower than the conventional loading path. The permeability curve and the volume strain curve show a clear symmetrical relationship, being the former in the form of a negative power function. Owing to the influence of irreversible deformation, the permeability difference and the damage of permeability mainly occur in the initial stage of loading-unloading, and both decrease as the number of cycles of loading-unloading increase. At the end of the first cycle and the second cycle, the permeability decreased in the range of 5.777 - 8.421 % and 4.311-8.713 %, respectively. The permeability decreases with an increase in the axial stress peak, and the damage rate shows the opposite trend. Under the same conditions, the permeability of methane is always lower than that of helium, and it shows a V-shape change trend with increasing methane pressures, and the permeability of the specimen was 3 MPa > 1 MPa > 2 MPa.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.8-14
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• 2017

Improvements in the standard of living and lifestyle have led to increased sales of frozen milk products, such as soft ice cream or slush. These frozen milk products are commonly made in a small refrigeration machine. In a soft ice cream machine, the freezer is composed of a concentric cylinder, where the refrigerant flows in the annul us and the ice cream is made in the cylinder by a rotating scraper. In this study, an optimization and performance evaluation were conducted on a soft ice cream machine having a freezer volume of 2.8 liters. The optimization was focused on the scraper rotation speed and the refrigerant path of the freezer. The measurements included the temperature, pressure and consumed power. At the optimized speed of 124 rpm, ice cream was produced in 6 minutes and 2 seconds, and the COP was 0.90. Through a flow visualization study using air-water, the refrigerant path was improved. The improved design reduced the ice cream making time significantly. The present results may be used for the optimization of other refrigeration cycles, including those of frozen food products.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.37-48
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• 2019

In geological $CO_2$ sequestration, the behavior of $CO_2$ within a reservoir can be characterized as two-phase flow in a porous media. For two phase flow, these processes include drainage, when a wetting fluid is displaced by a non-wetting fluid and imbibition, when a non-wetting fluid is displaced by a wetting fluid. In $CO_2$ sequestration, an understanding of drainage and imbibition processes and the resulting NW phase residual trapping are of critical importance to evaluate the impacts and efficiencies of these displacement process. This study aimed to observe migration and residual trapping of immiscible fluids in porous media via cyclic injection of drainage-imbibition. For this purpose, cyclic injection experiments by applying n-hexane and deionized water used as proxy fluid of $scCO_2$ and pore water were conducted in the two dimensional micromodel. The images from experiment were used to estimate the saturation and observed distribution of n-hexane and deionized water over the course drainage-imbibition cycles. Experimental results showed that n-hexane and deionized water are trapped by wettability, capillarity, dead end zone, entrapment and bypassing during $1^{st}$ drainage-imbibition cycle. Also, as cyclic injection proceeds, the flow path is simplified around the main flow path in the micromodel, and the saturation of injection fluid converges to remain constant. Experimental observation results can be used to predict the migration and distribution of $CO_2$ and pore water by reservoir environmental conditions and drainage-imbibition cycles.