• Journal of The Korean Association For Science Education
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• v.25 no.5
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• pp.583-594
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• 2005

This study examined 8th-graders' conceptions of force on a simple pendulum and investigated cognitive conflict and conceptual change through kinesthetic experience in swing. Participants of this study were guided to anticipate the direction of total force acting on a pendulum at three critical positions and observed it through swing experience. Having completed this, students read an article explaining the results they observed. Most of them considered gravity, tension, and motion-force to be the real forces acting on a pendulum in pre-test. Though they were interested in the activity and conceded their expectations to be different from observed results, the degrees of their cognitive conflict were not significantly high. In summation, 'interest' was the highest and 'anxiety' was the lowest. Most of the students memorized the direction of forces on a swing, but few could explain the reason behind the occurrence in an immediate post-test and delayed post-test.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.661-671
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• 2012

The purpose of this study was to analyze the core policies of local government directors by performing centrality analysis on their core policies using network text analysis method. From the research results, it was verified to some extent that major policies of local government directors were changing during the path to arrive at 5th civil election. However, according to policy type by Peterson (development policy, allocation policy and redistribution policy) it was found that they still focused on development policies. However, it is encouraging that the government directors elected in the 5th election started to pay attention to 'Culture' which is one of allocation policies.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.5
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• pp.409-414
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• 2013

In this work, corrosion of 304 stainless steel was evaluated by using acoustic emission(AE) technique. AE measurement system was set for detecting acoustic signal during accelerated corrosion test of the specimen. AE signal started to be detected after the time of pitting corrosion initiation was evaluated by anodic polarization curve. Pitting corrosion damage was confirmed by optical microscopic observation of the surface morphology. AE cumulative counts and amplitude according to corrosion time could be divided into three stages. These trends were discussed in relation with changing pitting corrosion mechanism. Feasibilities of AE technique for evaluation of corrosion damage and mechanism were suggested.

• Nuclear Engineering and Technology
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• v.8 no.2
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• pp.81-88
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• 1976

A flash method for measuring the unknown thermal property (the density, specific heat, or thermal diffusivity could be chosen as unknown) is described. The thermal diffusivity of UO$_2$ fuel samples is obtained from room temperature (300 K) to high temperature (1400 K). The specific heat is measured using a commercially available differential scanning calorimeter from room temperature to 500 K. The thermal conductivity of UO$_2$ fuel samples is calculated from the density, thermal diffusivity, and specific heat at constant pressure. The present results are in complete agreement with the usual trends for the thermal conductivity of dielectric materials, in which impurity levels are very important at low temperatures but become relatively unimportant at high temperatures. In addition, the thermal diffusivity values at room temperature are reexamined by measuring the thermal diffusivity of several UO$_2$ fuel samples with same level of doped Gd$_2$O$_3$.

• Proceedings of the Korean Society for Language and Information Conference
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• 2001.06a
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• pp.97-109
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• 2001

이 논문은 영어와 한국어에서 나타나는 완수동사(Accomplishment Verb)와 지속부사구(durative adverbial)의 상호작용에 대해서 논한다. Smith(1991)에 의하면 완수동사가 지속부사구와 결합하면, 동사와 부사구의 의미적 자질의 충돌을 피하기 위해서 완수동사의 상변환(Apsect Shift)이 일어난다. 본 논문은 이 상변환이 영어와 한국어에서 어떻게 실현되는가를 보이고, 이를 형식의미론에서 어떻게 기술할 수 있는가를 논한다. 완수동사가 지속부사구와 결합할 때, 영어와 한국어 모두에서 닫힌 완료 관점(closed perfective viewpoint)에서 열린 관점(open viewpoint)으로 관점 변환(viewpoint shift)이 일어난다. 그러나, 한국어의 상변환과 영어의 상변환이 완전히 일치하는 것은 아니다. 한국어의 관점변환은 완료관점도 아니고 미완료 관점도 아닌, 중립관점(neutral viewpoint)으로의 변환인 반면, 영어의 관점변환은 단순히 미완료 관점으로의 변환임이 논의된다. 이 주장은 한국어의 관점변환 구문은 이질적인 다수 사건의 연속 해석(heterogeneous sequential reading of multiple events)을 허용하는 반면, 영어의 관점변환구문은 오직 동질적인 단일 사건의 동시 해석 (homogeneous simultaneous reading of a single event)만을 허용한다는 사실에 의해서 지지 된다. 본 논문은 완수동사가 지속부사구와 결합할 때 일어나는 상변환에 대한 형식의 미론 분석을 Heim ＆ Kratzer (1998)의 틀에서 제시한다. 닫힌 관점에서 열린 관점으로의 상변환은 비가시적 시제 서법 운용자(covert temporal-modal operator)인 IMP를 지속부사구의 논항으로 설정하여 설명한다. IMP는 Dowty (1979)에서 미완료상의 모순(imperfective paradox)을 해결하기 위해서 설정한 PROG를 Heim ＆ Kratzer (1998)의 틀에 맞게 수정한 것이다. IMP는 평가 세계 (evaluation world)를 현실 세계(actual world)에서 가상 관성 세계(possible inertia would)로 변화시켜서, 완수동사의 종결점(ending point)을 현실세계에서 가상의 미래 세계로 움직이는 역할을 한다. 결과적으로, IMP는 완수동사의 닫힌 완료 관점을 현실세계에서는 열린 미완료 관점으로 변환시키되, 가상 관성 세계에서는 그대로 닫힌 관점으로 유지 시키는 효과를 가진다. 한국어와 영어의 관점 변환 구문의 차이는 각 언어의 지속부사구의 어휘 목록의 전제(presupposition)의 차이로 설명된다. 본 논문은 영어의 지속부사구는 논항의 하위간격

• Applied Microscopy
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• v.34 no.3
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• pp.179-184
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• 2004

Normal and abnormal morphology of the epididymal spermatozoa in the big white-toothed shrew, Crocidura lasiura were studied with the light and electron microscopy. Normal spematozoa were observed with a few abnormal spermatozoa. This indicates that abnormal morphology is no absolute indicator of infertility. However, the existence of the abnormal spermatozoa is related to infertility. Especially abnormal morphology of the sperm head is definitely associated with infertility. The following types of abnormal head morphology of the epididymal spermatozoa in the wild healthy adults of the C. lasiura were described: 1) Nucleus with lack of condensation of the nucleoplasm 2) Destructed acrosome 3) Folded acrosome and plasma membrane 4) Separation of the acrosome from the nucleus 5) Acrosome with irregular condensation 6) Wrongly located granules of the apical body.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1992.10a
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• pp.8-13
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• 1992

최근 우리 나라도 자동차의 수요가 급격히 늘어나고 있고, 생산량도 급증하 고 있어 자동차 공업이 산업의 최고의 위치를 확보하게 되었다. 자동차는 최 신 종합 기계 구조물로서 전기, 전자, 제어에 이르기까지 거의 모든 분양의 학문적 이론과 기술을 도입하는 최첨단의 기계 장비인것이다. 따라서 그 부 가가치 또한 매우 큰 것이다. 자동차의 성능을 결정짓는 가장 커다란 요소는 주행 성능과 안정성 및 조종성이다. 주행성능이라 함은 자동차의 종방향 운 동에 관한 성능으로서 기관의 동력에 지배적인 영향을 받는 성능(동력 성능) 과 그 밖의 성능(타향 성능, 제동 성능)으로 구분된다. 또 안정성과 조종성이 라함은 자동차의 횡방향 운동에 관한 성능으로서 로울링과 요우잉을 포함시 킨 곡선 운동에 관한 성능을 일컫는다. 이러한 운동 성능을 좌우하는 것은 구조적인 설계의 양부와 스프링이나 댐퍼의 성능일 것이다. 자동차의 수많은 부품 중의 다수가 국산화 되어 있지 아니하고, 또한 이러한 부품들의 성능을 시험할 수 있는 장비의 수입 의존도가 높은 것은 업계나 학계 등에서 앞으 로 많은 연구가 이루어져야 할 점이다. 자동차의 충격 흡수기(shock absorber)의 검사기도 또한 수입 시험기에 의존하고 있었던 것이 현실이었 다. 이에 본 연구진은 이 검사기의 국산화에 착수 한 것이다. 자동차에 있어 서 충격 흡수기는 지면에서 오는 충격을 급속히 흡수하는 역할을 하여 자동 차의 주행 성능과 안정성을 높혀 주며, 승차감을 높혀 주는 중요한 부품이 다. 따라서 충격 흡수기의 양부의 판정은 대단히 중요한 것이다. 본 연구에 서는 충격 흡수기의 충격 흡수력(감쇠력)을 측정하여 감쇠 특성을 정도 높게 파악할 수 있는 시험기를 만드는데 그 목적을 두고 있다. 연구는 시험기의 구동부를 제작하는 기계부와, 제어 및 계측의 하드웨어를 담당하는 전기.전 자부및 실제로 기계를 구동, 제어하고 측정 결과를 기록하고 출력하는 부분 을 담당하는 소프트웨어 개발부로 나누어서 진행하였다.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.154-161
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• 2015

A novel multiframe super-resolution (SR) algorithm is presented to overcome the limitation of existing single-image SR algorithms using motion information from adjacent frames in a video. The proposed SR algorithm consists of three steps: i) definition of a local region using interframe motion vectors, ii) multiscale patch generation and adaptive selection of multiple optimum patches, and iii) combination of optimum patches for super-resolution. The proposed algorithm increases the accuracy of patch selection using motion information and multiscale patches. Experimental results show that the proposed algorithm performs better than existing patch-based SR algorithms in the sense of both subjective and objective measures including the peak signal-to-noise ratio (PSNR) and structural similarity measure (SSIM).

• Korean Journal of Health Education and Promotion
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• v.29 no.5
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• pp.103-113
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• 2012

Objectives: This study aims to identify the effects of environmental characteristics of the community on adults' drinking problems with held constant effects of characteristics of drinkers themselves. Methods: A multi-level regression analysis was employed to differentiate the variances accounted for by measurements both at individual and group levels. Data on individual demographic, behavioral, and mental health status were obtained from the Community Health Survey conducted in 2009 in the province of Kyunggido, which include 41,376 respondents aged 19 and over. This study included 28,335 adults who were classified as drinkers. They were from 45 communities(si, gun, or gu) for which data on contextual characteristics were collected by secondary data available on local government websites and KOSIS(Korea Statistical Information System). Results: Multi-level analyses showed that the variance of the dependent variable, harmful use of alcohol measured by alcohol use disorder identification test was independently accounted for by variance of independent variables at group level, including number of on-premises alcohol outlet per inhabitant and divorce rate, with held other independent variables of the model controlled. Conclusions: This study confirms that in order to prevent and reduce harms caused by harmful use of alcohol requires restricting physical availability of alcohol in the community where the drinker lives.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.4
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• pp.463-476
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• 2010

Inadequate or unstable posterior support cause extrusion of antagonistic teeth and overloading of remaining teeth. Extrusion of antagonistic teeth result in collapsed occlusal plane and decreased prosthetic space. Also, overloading of remaining teeth increase occlusal wear or anterior extrusion of anterior teeth, which is resulting in loss of anterior guidance, disharmony of occlusion and decreased prosthetic space. In this case, careful evaluation of OVD(occlusal vertical dimension) is the general first trial to regain appropriate function and esthetics. Simultaneously, adequate anterior guidance and harmonious occlusal plane should be established in the repeatable reference position of the mandible. We report this case because severely worn dentition achieved functional and esthetic results from full mouth rehabilitation with increased vertical dimension and use of centric relation.