• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.113-113
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• 2008

Cu CMP (Chemical Mechanical Planarization) has been used to remove copper film and obtain a planar surface which is essential for the semiconductor devices. Generally, it is known that chemical reaction is a dominant factor in Cu CMP comparing to Silicon dioxide CMP. Therefore, Cu CMP slurry has been regarded as an important factor in the entire process. This investigation focused on understanding the effect of corrosion inhibitor on copper surface and CMP results. Benzotriazole (BTA) was used as a corrosion inhibitor in this experiment. For the surface analysis, electrochemical characteristics of Cu was measured by a potentiostat and surface modification was investigated by X-ray photoelectron spectroscopy (XPS). As a result, corrosion potential (Ecorr) increased and nitrogen concentration ratio on the copper surface also increased with BTA concentration. These results indicate that BTA prevents Cu surface from corrosion and forms Cu-BTA layer on Cu surface. CMP results are also well matched with these results. Material removal rate (MRR) decreased with BTA concentration and static etch rate also showed same trend. Consequently, adjustment of BTA concentration can give us control of step height variation and furthermore, this can be applicable for Cu pattern CMP.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.843-850
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• 2016

In this paper, we propose a digital controller design process for the interleaved type of a boost PFC (Power Factor Correction) converter which can disperse the heat of the switching devices due to the interleaved topology. We establish a mathematical model of a boost PFC converter and propose a controller design method based on the root locus. The performance of the designed controller is verified by simulations. The measurement of the input voltage, inductor currents, and the converter output link voltage are needed for the control of the converter system which consists of a power unit and a control unit where a high-performance 32-bit microcontroller is used. The adjustment of A/D conversion timing is also needed to avoid high frequency noise generated when the switches on/off. It is illustrated by the real experiments that the designed control system with the properly adjusted ADC timing satisfies the given performance specifications of the interleaved boost PFC converter in the on-board slow battery charger.

• Journal of Information Technology Applications and Management
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• v.20 no.4
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• pp.315-338
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• 2013

As a result of New media that affects the marketing system, it is appeared a new marketing system called Market Platform in terms of market governance of trading. Market Platform is a new marketing system for ideal market system through the community structure from a hierarchy structure. It is determined that Market Platform as the role of adjustment of each side of market, buyer and seller, developed an existing marketing system. In this study, to target the Market Platform has recently emerged as the center of the market management in the new media environment. This study investigates what characteristics and impact of infrastructure of Market Platform will affect the cognitive impact on both buyers and sellers to clarify the impact on the self efficacy of the shopping process. Through this investigation, modeling for the impact that new media environment will attract Market Platform will be developed from the investigation of attractiveness of mobile market platform environment. Changes in the technical media environment gave the characteristics of the customer in the market platform, so consumers could involve not only consumed, but also manufactured. Thus, it is possible to increase the attractiveness if market must be able to not only for the convenience of shopping, but also make people to enjoy the experience of value co-creation. In other words, the new media, as a result of affecting the marketing system, mobile market platform is organized around the market of communication base. Network centrality, visible openness, ubiquitous multiplexity, 3 properties of new media increase the market self-efficacy of their customers. Therefore, the structure of market platform that enhance self-efficacy has higher attractiveness.

• Journal of Digital Convergence
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• v.13 no.9
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• pp.49-56
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• 2015

Korea government has established clear cost estimation standard based on a survey of e-learning contents development cost and presented 'e-Learning Contents Development Cost Estimation Guidelines' that reflect the characteristics of the e-learning industry. However, if there is no institutional support, this guideline and system fails to achieve the purposes and objectives. And it is likely to be facing a dead document. Therefore, the policy foundation is required. This study suggested the following policy; stepwise activation of cost estimation standard, enact announcement and periodically adjustment of cost estimation standard, installation and operation of cost estimation standard operational committee, conjunction with the e-learning industry survey, cultural diffusion of co-owned copyright, systematic monitoring of the e-learning contents development process, research on activating policy of cost estimation standard, conjunction with the standard contract for enhancing policy effectiveness.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.193-202
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• 2018

The purpose of this study was to analyse the effects of youth depression and aggression and the effects of peer alienation in the process. To that end, the hierarchical regression analysis was used for 869 male teenagers and 800 female teenagers based on the data 7th wave of Korean Youth Panel Survey. Filly, In order to verify the meadiating effect of Peer Reject, bootstrapping method was used. The first seven panels Major analysis results are as follows. First, depression directly affected school adjustment of male and female adolescents. it turns out that the more depressed the young men and women are, the more aggressive they are. Second, In terms of depression and aggression among young men, peer alienation plays a role as a medium and that it does not work in the case of female. It also demonstrated that men's peer rejection has a media-effect in both gender depression and aggression and recommended discriminatory intervention based on gender.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.5
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• pp.371-378
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• 2018

Internal detonation of a warhead inside a compartment of naval vessel can result in serious blast damages including plastic deformation and rupture of the structural members especially bulkhead due to the huge explosive impact pressure, fragments and high temperature flame. To secure watertight integrity and to prevent the domino-type flooding of neighbouring compartments caused by the rupture of bulkheads, it is necessary to develop the structural design technology of Blast Hardened Bulkheads(BHB) which can resist the blast impact pressure of threatening weapons to increase the survivability of naval vessels. This study dealt with the simplified structural response analysis of BHB under impact pressure of confined explosion and aimed to develop the efficient and rational design method of BHB and joint structures which can be applied at initial design stage. The present 1st report dealt with the phenomena of explosive detonation surveying the preceding experimental/theoretical research and the characteristics of time history of blast pressure including the peak value and duration time were examined. And to predict the large plastic deformation behaviors of BHB by the huge blast pressure reasonably, the plastic hinge method including the membrane effects was formulated. It was applied to the simplified structural design equations. The following report will deal with the application and adjustment process of the structural scantling equations to the actual BHB design and verification of validity of them.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.37 no.5
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• pp.19-28
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• 2000

It is not so easy to control the wheeled mobile robot because of some causes like non-holonomic constraints. To overcome these problems, a controller that PD system is combined with fuzzy process is composed of several steps that have each separate algorithm and niche search algorithm and immune algorithm is applied partly. Output term set is changed by search that is performed to get optimal elements and then the rule base is also reformed. The fitness for the altered system is estimated and the surplus elements are removed. After the adjustment of output term set and rule base is finished, input and output membership functions is tuned.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.5-13
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• 2017

To lunch the Korea Space Launch Vehicle-II(KSLV-II), the second launch complex will be constructed on the Naro Space Center and Kerosene Filling System (KFS) will be also installed newly. KFS of KSLV-II launch complex system is being designed based on Naro Launch Complex. But this must supply fuel to fuel tanks of the vehicle with only a supply pump because KSLV-II is a 3-stage launch vehicle unlike Naro Launch Vehicle or Test Launch Vehicle (TLV). A sudden rise of pump output pressure is recognized during fuel filling scenario selection process. This occurs because return flow can not actively deal with a lot of flow change using flow control method of orifice type. To solve this problem, it is verified that fuel can be stably supplied by installation of accumulator and an appropriate adjustment of filling mode change sequence through flow analysis of various cases.

• Hwankyungkyoyuk
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• v.22 no.1
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• pp.97-109
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• 2009

The purpose of this study is to grasp the degree of recognition of the ESD(Education for Sustainable Development) form Technology Home Economic teachers in high schools, to analyze contents related to the ESD within the textbooks, and to propose the improvement method of the textbooks. As a result, first, the degree of recognition on the ESD was less than about 30.1% in Technology Home Economic teachers. Second, the content and factor criterions for the ESD were developed on the basis of the previous studies. They are suitable for applying to the Vehicle Chapter in the textbooks and are including 9 contents and 7 factors, respectively. Third, the contents related to the ESD within a Technology. Home Economic textbook showed 36.1% in Technology, 33.8% in Home Economics including social and cultural(44.7%), environmental(47.1%), and economic contents(8.2%). But they in the Vehicle Chapter within the textbooks presented 69.1%, 4.8%, 26.1% in social and cultural, environmental, and economic contents, respectively. Finally, the improvement method of the new textbook for the Vehicle Chapter is to adopt issued factors including the suitable adjustment on the vehicle structure and safety as well as the supplement of environmental contents related to the ESD. In addition, it is necessary to contain the contents such as the developing process of environment-friendly vehicles, the economically sustainable consumption strategy, and the cause-and-effect relationship with the global warming in the new textbook.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.178-183
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• 2002

A high molecular ar weight water-soluble chitosan (WSC) with an average molecular weight of 300 kD and a deacethylation level of over 90% was produced using a simple multi-step-membrane separation process. It is known that WSC prevents obesity induced by a high-fat diet. Consequently, this study investigated whether or not WSC improved the ovarian dysfunction caused by obesity in mice. The mice were fed a high density protein and lipid diet for weeks, followed by the administration of WSC at 480 mg/kg body weight per day for 4 days. Thereafter, the changes in body weight, ovulation rate, in vivo and in vitro fertilization and emboryonic development were measured . WSC markedly reduced the body weight of obese mice fed with a high-fat diet, but not in mice fed with a normal diet. WSC had siginificant effects on the ovulation rate, both the in vivo and in vitro fertilization rates and embryonic development. These results indicate an improvement in the ovarian and oviduct dysfunction caused by obesity, and suggest an adjustment in the internal secretions and metabolic functions.