• Proceedings of the KACD Conference
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• 2003.05a
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• pp.288-288
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• 2003

1960년대 중반부터 도입된 구치부 복합레진 수복은 복합레진과 접착시스템의 향상된 물성 때문에 구치부 사용에 대한 주목할 만한 결과를 보고하고 있다. 현재는 다수의 1급, 2급 수복물에 복합레진이 적응증으로 기술되며, 사실상 미국치과의사 협회(ADA)도 초기와 중등과 크기의 병소를 보존적 I, II급 와동으로 형성된 뒤 복합레진으로 수복하는 시술의 적절성을 인정하고 있다. ADA는 "복합레진을 유치나 영구치의 I급, II급, V급 수복에 올바르게 적용하면 아발감의 수명에 뒤지지 않는다."라고 기술하고 있다. 이에 본 강연에서는 I급과 II급 복진레진 수복을 위한 관련된 재료들의 특성과 단점들을 극복하기 위한 노력들을 설명하고자 한다. 특히 중합수축과 관련된 문제점들을 해결하기 위해 제시되고 있는 방법들의 임상적 적용 가능성의 한계와 술후 과민증을 줄이기 위한 방법, 그리고 구치부에 적용된 레진들의 마모를 줄일 수 있는 방법들을 모색하고 한다. 더불어 구치부 복합레진 수복을 위한 임상 시술 시 가장 흔하게 발생되는 단조로운 인접면 외형 형성 및 접촉점 개방의 문제점을 인식하고 이를 막기 위한 노력 및 기구들의 사용 조작에 대해 토의해 보고자 한다.

• The Journal of the Korean dental association
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• v.34 no.12 s.331
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• pp.861-865
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• 1996

복합레진의 성질과 삽입기술에 대한 많은 개선들이 1970년대부터 이루어져 왔으며 많은 실험적 연구와 임상적 연구를 통해 제 1급 및 제 2급 와동에 적용가능한 다양한 복합레진이 개발되었다. 1980년대 초반부터 많은 제품들이 아말감이나 금수복물의 대용물로써 소개되고 있으며, 장기적인 임상연구에서 색깔의 안정성, 적은 미세파절, 감소된 마모도와 재발성 우식증의 감소등 좋은 개선점들이 알려졌으며, 교합접촉을 하지 않거나 거의 하지 않는 구치부 복합레진 수복에서 표면 상실이 거의 나타나지 않음이 관찰되었다. 그러나 많은 힘이 가해질 때 외형을 상실한다는 점이 아직도 가장 큰 문제점으로 남아있다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.5
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• pp.375-380
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• 2012

In this study, dynamic load and dynamic contact force between a building block and wire ropes of a goliath crane are calculated during lifting or turn-over of a building block for the design of an optimal lug arrangement system. In addition, a multibody dynamics kernel for implementing the system were developed. In the multibody dynamics kernel, the equations of motion are constructed using recursive formulation. To evaluate the applicability of the developed kernels, the interferences and dynamic contact force between the building block and wire ropes were calculated and then the hull structural analysis for the block was performed using the calculation result.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.2
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• pp.64-72
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• 2001

In this paper, forward Zero Voltage Switching Multi Resonant Converter(ZVS MRC) for non-contact charging energy transmission is reposed. The forward ZVS MRC is effective in adsorbing parasitic element as well as minimizing the switching loss. That can accommodate very high frequency. So forward ZVC MRC is applied to non-contact charging energy transmission. Used converter has saperatable transformer and synchronous rectifiers. Coupling coefficient(k), leakage inductance, coupling inductance and resonant frequency are observed for the air gap. By using the observed value, this circuit is designed and implemented. This proposed circuit is simulated by the PSPICE and experimented. The voltage stress of a main switch and the output power of the converter are measured. This paper show that is compatible for non-contact charging energy transmission.

• Journal of Preventive Medicine and Public Health
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• v.30 no.2 s.57
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• pp.381-391
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• 1997

In an epidemiological study of metal workers exposed to metalworking fluids (MWF), the prevalence time of Evolution, seasonal occurrence and clinical type of contact dermatitis were investigated. Compostional analysis of MWF with HPLC, dermatological examination and two consecutive questionnaire surveys were conducted. Study population was divided into two groups ; workers contact to cutting oil and workers contact to rust preventive oil. In the analysis of MWF, aliphatic hydrocarbons, having 12-20 carbons, was most common composition(49.04%) of cutting oil otherwise, major contents (90.99%) of the rust preventives oil were aliphatic hydrocarbons composed of 6-9 carbons. The frequency (point prevalence) of contact dermatitis(CD) was 7(12.7 per 100 subjects) in the dermatological examination of 55 workers. As the result of second survey for contact dermatitis, cumulative prevalence of oil working full-time and recent 1 year prevalence in two groups were 28.0, 16.7 and 15.1, 12.5 per 100 subjects. There were no difference in the prevalence of CD by oil, age, oil contact duration. Summer is the most common evolution season in workers exposed to cutting oil, but not in workers exposed to rust preventive oil. Major clinical type of CD was erythematous papules in both groups. It presents the importance of preventive measures that 51.1% suffer from contact dermatitis had medical care at their own expense, and 47.1% of them felt serious about their contact dermatitis. From the fact that 68.6% think cotton gloves protective apparatus, we emphasize the need for health education.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.1
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• pp.34-42
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• 1986

An interface of a circular arc formed by two isotropic, homogeneous elastic materials is investigated. It is shown that L integral satisfies the conservation law for the interface if it is perfectly bonded, in frictionless contact or separated such as in a crack with the origin of the coordinate system being located at the center of the circular arc. The property of path independence of the L integral is applied to an interfacial crack problem, to obtain the stress intensity factors, where the interfacial crack is located along the arc of the circular inclusion embedded in infinite matrix. It is assumed here that the contact zone exist as in the model proposed by Comninou, thus removing the overlapping of the materials along the interface. Another example is shown for case of a circular interfacial crack in the matrix of finite size, where the stress intensity factors are determined by computing a value of the L integral numerically along the path far from the crack tip.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.267-268
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• 2013

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.280-284
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• 1998

신체 보호와 체온유지를 담당하는 피부는 인체 최대의 감각기관이다. 피부에는 온각, 냉각, 압력, 통증, 촉각, 진동 둥을 느끼는 외수용감각기들이 산재되어 있다. 그 중에서 촉감은 건축 자재, 필기구 재질, 자동차 내장재, 의류 원단과 안감 등 신체와 접촉하는 소재에 있어 제품의 질을 결정짓는 중요한 요소이다. 특히 섬유에서의 질감이란 경제적인 면과 직결되는 문제를 안고 있다.(중략)

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.167.2-167
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• 2000

• 대한방사선방어학회:학술대회논문집
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• 2009.04a
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• pp.290-291
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• 2009