• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.131-131
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• 2018

최근 절삭공구산업은 자동차, 항공기, IT, 선박, 에너지 등 첨단산업의 증가로 인해 CGI, CFRP, 내열합금 등 난삭재의 수요가 증가하고 있다. 난삭재는 고내열, 고경도, 초경량 같은 특성을 지니며 우수한 기계적 물성을 갖지만 가공의 어려움이 있어 산업에 적용하는데 한계가 있다. 이러한 한계를 극복하기 위해 개발된 가공기술 중 하드 코팅은 공구코팅비용 대비 공구의 표면경도와 수명을 효율적으로 향상시킬 수 있다고 알려져 있다. 대표적인 하드코팅으로는 AlN계, TiN계 코팅이 있다. 이러한 코팅의 경우 높은 기계적 물성과 우수한 내마모성으로 인해 절삭공구의 성능을 향상시킬 수 있기 때문에, 많은 연구가 진행되고 있으며 절삭공구산업에서 각광받고 있다. 기존 선행연구 결과에 따르면 질화물 코팅의 우수한 물성은 질화물(Nitride) 생성 및 질화 공정에 의한 코팅층의 고밀도화에 의해 나타난다고 알려져 있다. 그 중에서 AlCrN coating은 우수한 내마모성 및 향상된 고온경도를 갖고 있다. AlCrN based coating에 미량의 원소를 첨가하여 기존 AlCrN coating의 기계적 특성을 더욱 향상 시킨 coating은 일반적인 고성능 코팅 대비 공구수명이 길다고 알려져 있으며, 전반적으로 우수한 특성에 의해 전 세계적으로 습식 및 건식 기계 가공 용도로 사용되고 있다. 본 연구에서는 AlCrN based coating에 미량의 원소를 첨가한 coating의 우수한 기계적 특성의 원인을 규명하기 위해 텅스텐카바이드(WC) 기판 위에 아크 이온 플레이팅 장비를 이용하여 AlCrN based coating을 증착 시킨 sample을 분석하였다. 결정구조 및 상 분석을 위해 X선 회절분석(XRD)을 실시하였으며, 미세 구조를 분석하기 위해 전계방출형 주사전자현미경(FE-SEM), 투과 전자현미경(TEM) 분석을 실시하였다. 또한 코팅층의 화학적 성분 분석을 위해 EDX분석을 실시하였으며 기계적 특성 평가를 위해 나노압입시험(Nano-indentation test)을 진행하였다.

• Journal of The Korean Association For Science Education
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• v.11 no.1
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• pp.51-57
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• 1991

This study pursued to find out the degree to which educational objectives are pursued in the 3rd and 5th grade science instructional of an elementary school. Twenty science instruional hours are observed during two month from May to July, 1989. Klopfer's science educational objectives system is used as the tool of objective analysis. Questionnaires for the ideal proportions of the educational objectives are answered by the professors and elementary school teachers. The writers regarded those results as the ideal proportions of the educational objectives. Results from the analysis of the instruction are as follows : 1. Results from analysis of the instruction in the third grade are as follows : knowledge and comprehension (A. 0) objectives are found to be pursued. about 40%. scientific inquiry process(B. 0-E. 0) objectives, about 29%, application of scientific knowledge and methods(F. 0) objectives. about 10%, manual skills(G. 0) objectives, about 11%, scientific attitudes and interests(H. 0) objectives, about 10% and orientation(I. 0) objectives is not pursued. 2. Results from analysis of the instruction in the fifth grade are as follows: knowledge and comprehension(A. 0) objectives are found to be pursued. about 31%, scientific inquiry process (B. 0-E. 0) objectives. about 38%, application of scientific knowledge and methods (F. 0) objectives, about 13%, manual skills(G. 0) objectives, about 7%, scientific attitudes and interests(H. 0) objectives, about 10%. 3. Results from the ideal proportions are as follows : Knowledge and comprehension(A. 0) objectives, 20.5%, scientific inquiry process(B. 0-E. 0) objectives, 46.5%, application of scientific knowledge and methods(F. 0) objectives. 8%, manual skills(G. 0) objectives. 9.5%, scientific attitudes and interests (H. 0) objectives, 9% and orientation(I. 0) objectives, 6.5%. 4. "You ideality index" is 29 in the third grade and 23 in the fifth grade. Science instruction of the fifth grade can be interpreted to be nearer to the ideal instruction in terms of educational objectives.

• Journal of the Economic Geographical Society of Korea
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• v.17 no.4
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• pp.601-623
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• 2014

This paper is to analyze critically policy and discourse of creative economy and creative city. Applying the concept of 'policy transfer' or 'policy mobility', It points out that it may be inevitable for a certain policy or discourse developed in Western society to change its contents and characteristics in its international diffusing process. And then, this paper describes political contexts and process in which the policy and discourse of creative city of a former mayor of Seoul, Oh, Se-Hoon, during the late part of the 2000s, and those of creative economy of the current president, Park, Geun-Hye, have been suggested and pursued, arguing that those policies and discourses, having been distorted and lack of concrete contents, have functioned as a key ruling tool or political rhetoric. In particular, this paper concludes that the policy and discourse of creative economy of the current government would have little positive effect due to excluding intentionally policy of economic democracy and ignoring unintentionally policy of creative city, which seem to have an inherent relationship with that of creative economy.

• Journal of Veterinary Clinics
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• v.24 no.1
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• pp.46-50
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• 2007

A 7-year-old female, Jindo dog was referred to the Veterinary Teaching Hospital with mild dyspnea and anorexia due to a gunshot trauma. The dog was wounded in the thoracic region 3 days ago. Plain radiographs showed the left 8th rib fracture, interstitial pattern in the left caudal lung field and pleural effusion. Abdominal radiographs showed the lead bullet. Computed tomographs(CT) showed the size of pulmonary contusion, laceration, lung parenchymal injuries, hemothorax and perforation of abdominal wall. The therapeutic plan was based on abnormalities seen on CT scans but not clearly seen in survey radiographs. Thoracic CT significantly provides even more informations compared with the corresponding radiographs in thoracic gunshot trauma. Although thoracic survey radiographs are useful as a screening tool, CT is highly sensitive in detecting thoracic injuries after thoracic trauma and is superior to routine thoracic survey radiographs in visualizing lung contusion, pneumothorax and hemothorax. Therefore, we recommend CT in the initial diagnostic work-up of patients with thoracic injuries and with suspected chest trauma because early and exact diagnosis of all thoracic injuries along with sufficient therapeutic consequences may reduce complications.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.373-381
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• 2000

Serial ultrasonographic examinations were performed on pregnant Korean Jindo bitches. Measurements of inner chorionic cavity diameter and fetal head diameter were made from pregnancy day 15 to parturition. These measurements were converted retrospectively based on the day of parturition (day 0). The data of inner chorionic cavity diameter obtained from day -42 to day -25 and fetal head diameter obtained from day -24 to day -1 were used to prediction of parturition day. Formulas for the prediction of parturition day using the method of least squares were derived. These formulas were then used to predict parturition dates based on single measurements of inner chorionic cavity diameter or fetal head diameter in 17 additional pregnant Korean Jindo bitches. Predicted date of parturition was then compared to actual whelping date. In the prediction of parturition based on inner chorionic cavity diameter, 7 of 10 bitches were coincided prediction date and actual whelping date, and the prediction was accurate to within 1 day in 3 of 10 bitches. The prediction of parturition based on fetal head diameter was accurate to within 1 day in 6 of 7 bitches and within 2 days in 1 of 7 bitches. In conclusion, the ultrasound measurement of inner chorionic cavity diameter and fetal head diameter are practical and accurate tool in the prediction of parturition.

• Information Systems Review
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• v.13 no.2
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• pp.73-87
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• 2011

This study measures the research productivity of IS researchers in South Korea. In this study, we select 11 leading IS journals, those are MIS Quarterly(MISQ). Information Systems Research(ISR), Journal of Management Information Systems(JMIS), Journal of the Association for Information Systems(JAIS), European Journal of Information Systems(EJIS), Information Systems Journal(ISJ), Decision Support Systems(DSS). Communications of the Association for Information Systems(CAIS), Information and Management(I&M), Journal of Strategy Information Systems(JSIS), and Journal of Information Technology(JIT). We analyzed the published articles of IS researchers in South Korea between 2007 and 2009 using scientometric techniques for measuring research productivity. The findings of this study provide evidences that IS research productivity has become a comprehensive information to business tool to assist advertizing of electing student of IS department and university, and take a person into IS professor in the IS job market. IS productivity research on Korean IS researcher rarely showed. The unique study showed valuable contributions for academicians to provide a better comprehension of publishing trend of leading IS journals.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.340-343
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• 2008

Recently, the construction industry is getting more complex and sophisticated having the characteristics of a mega project. Mega project pursues a value that can't be gained with an approach of seeing a project as just a simple sum of different parts but a mutual combination. Hence to reach the goal, program management is needed rather than project management. program management can be seen as a 'total project management' and for an efficient program management prompt support for decision making is required. However, the current supporting method can't fulfill the requirements, therefore, need a tool to support the decision making and a IETM is expected to take this role. Despite the a lot of expected advantages of IETM, it is still difficult to apply because of the frequent changes of information in specifications and laws. In this research, as part of developing a IETM, we aim to propose a system frame which is based on the analysis of processes of a project. Moreover, based on this frame, a database will be built to contribute towards the application of construction IETM in the domestic construction industry.

• Clinical and Experimental Pediatrics
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• v.55 no.8
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• pp.301-305
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• 2012

Nonketotic hyperglycinemia (NKH) is a rare inborn error of amino acid metabolism. A defect in the glycine cleavage enzyme system results in highly elevated concentrations of glycine in the plasma, urine, cerebrospinal fluid, and brain, resulting in glycine-induced encephalopathy and neuropathy. The prevalence of NKH in Korea is very low, and no reports of surviving patients are available, given the scarcity and poor prognosis of this disease. In the current study, we present a patient with NKH diagnosed on the basis of clinical features, biochemical profiles, and genetic analysis. Magnetic resonance spectroscopy (MRS) allowed the measurement of absolute glycine concentrations in different parts of the brain that showed a significantly increased glycine peak, consolidating the diagnosis of NKH. In additional, serial MRS follow-up showed changes in the glycine/creatinine ratios in different parts of the brain. In conclusion, MRS is an effective, noninvasive diagnostic tool for NKH that can be used to distinguish this disease from other glycine metabolism disorders. It may also be useful for monitoring NKH treatment.

• Structural Engineering and Mechanics
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• v.25 no.4
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• pp.445-466
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• 2007

As the LNG (Liquefied Natural Gas) tank contains cryogenic liquid, realistic thermal analyses are of a primary importance for a successful design. The structural details of the LNG tank are so complicated that some strategies are necessary to reasonably predict its temperature distribution. The proposed heat transfer model can consider the beneficial effects of insulation layers and a suspended deck on temperature distribution of the outer concrete tank against cryogenic conditions simply by the boundary conditions of the outer tank model. To this aim, the equilibrium condition or heat balance in a steady state is utilized in a various way, and some aspects of heat transfer via conduction, convection and radiation are implemented as necessary. Overall thermal analysis procedures for the LNG tank are revisited to examine some unjustifiable assumptions of conventional analyses. Concrete and insulation properties under cryogenic condition and a reasonable conversion procedure of the temperature-induced nonlinear stress into the section forces are discussed. Numerical examples are presented to verify the proposed schemes in predicting the actual temperature and stress distributions of the tank as affected by the cryogenic LNG for the cases of normal operation and leakage from the inner steel tank. It is expected that the proposed schemes enable a designer to readily detect the effects of insulation layers and a suspended deck and, therefore, can be employed as a useful and consistent tool to evaluate the thermal effect in a design stage of an LNG tank as well as in a detailed analysis.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.10
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• pp.1061-1066
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• 2011

In this study, the flow characteristics of an injection nozzle installed in a high-pressure holder for improving productivity were determined. The inlet velocity, nozzle inflow angle, and nozzle outlet diameter were selected as design factors having an influence on the flow characteristics, and numerical analysis was conducted for these factors. As the inlet velocity is high and the nozzle outlet diameter is small, the pressure and velocity of the injected flow are high. In the case of the nozzle inflow angle, the variation of flow characteristics according to angle was slight, but the highest pressure and velocity were found at $15^{\circ}$. In addition, the possibility of chip elimination by the injected flow was analyzed on the basis of the numerical results.