• 대한심미치과학회지
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• 제8권1호
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• pp.36-44
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• 1999

No one really doubts that the hottest area of dentistry in 21st century would most likely be 'implant'. With the support of a vast amount of research, implant has been successfully and rapidly absorbed into the field of general dentistry including private practitioners. For teeth with hopeless(or refractory) periodontitis or periapical pathosis, with no hesitation most dentists would think extraction as the sole treatment option followed by prosthodontic replacement possibly including implant. Not many dentists would take Trasplantation/Replantation as another treatment option for a particular condition. Dentistry is often more focused on 'Restoration' than 'Preservation' of natural dentition. 'Biologic Implant' is obviously much closer to the concept of 'Preservation'. Many different types of biologic implant system have been introduced to clinical dentistry so far. Many of those have failed to earn reasonable acknowledgement despite of the clinical success they brought. For some reason biologic implant has rather been alienated for long time. RPI(Ring Pin Implant) is designed to improve the prognosis and success rate of transplanted/replanted teeth. RPI is a Ti-based custom made implant system. It is fabricated either by electric casting or milling process. The major feature RPI gas is the 'ring & hole' structure. The hole should be no less than 1mm diameter to allow bone bridge formation thru it. The ring structure and bone bridge formation creates anti-torque activity, which largely increases the 'initial stability' of the transplanted/replanted teeth. It is also reported that RPI is beneficial in the aspect of resisting root resorption following replantation/transplantation procedure.

• 동의신경정신과학회지
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• 제18권3호
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• pp.209-224
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• 2007

Metabolic syndrome consists of several risk factors of metabolic origin like elevated blood pressure, abdominal obesity, elevated triglyceride concentrations, decreased HDL-cholesterol concentrations, and elevated fasting glucose. It appear to directly increase the development of atherosclerotic cardiovascular diseases which leading to cardiovascular diseases in later life. This 39 years female patient was diagnosed schizophrenia at the age of 17. but she didn't take reasonable treatments. during 20 years, she stayed in home and lived unsuited life with her family. As a result she gains heavy weight and centeral obesity, diabetic mellitus and hypertention, and developed cerevral vascular accident twice. This patient was treated with herb medication, acupuncture, western medication, psychotherapy primarily in focusing of pre-illness state(未病) as well as the stagnation of phelm. During 140 days of treatment from admission, before 2nd attack tbe patient showed improvement of Lt. hemiparesis but after second attack improved a little. And symptom of schizophrenia improved considerably. Also diet habit changed.

• 한국전자통신학회논문지
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• 제9권2호
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• pp.255-260
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• 2014

최근에 열화상 카메라는 수 변전 설비의 열화 상태를 진단하는데 많이 사용하고 있다. 그러나 자장이 높은 곳에서는 열화상 카메라의 전자부가 높은 자장으로 인하여 제대로 동작하지 못하는 문제점이 발생한다. 이를 해결하기 위해 일반적으로 반사경을 사용할 수 있으나 반사경의 휨 등에 의해 반사 성능이 떨어지는 문제점이 있다. 본 논문에서는 이러한 문제점을 극복하기 위하여 아크릴 판에 알루미늄을 코팅하여 설계한 후 이를 제작하여 측정의 오차를 줄이고 측정 효율을 높이는 방법을 제시한다.

• Journal of Electrical Engineering and Technology
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• 제12권4호
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• pp.1406-1416
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• 2017

In complex and large-scale industries, properly designed fault detection and identification (FDI) systems considerably improve safety, reliability and availability of target processes. In thermal power plants (TPPs), generating units operate under very dangerous conditions; system failures can cause severe loss of life and property. In this paper, we propose a bagged auto-associative kernel regression (AAKR)-based FDI approach for steam boilers in TPPs. AAKR estimates new query vectors by online local modeling, and is suitable for TPPs operating under various load levels. By combining the bagging method, more stable and reliable estimations can be achieved, since the effects of random fluctuations decrease because of ensemble averaging. To validate performance, the proposed method and comparison methods (i.e., a clustering-based method and principal component analysis) are applied to failure data due to water wall tube leakage gathered from a 250 MW coal-fired TPP. Experimental results show that the proposed method fulfills reasonable false alarm rates and, at the same time, achieves better fault detection performance than the comparison methods. After performing fault detection, contribution analysis is carried out to identify fault variables; this helps operators to confirm the types of faults and efficiently take preventive actions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.90-92
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• 2005

This paper addresses the analysis of interruption costs and the studies made through the direct interview with Korean Industrial customers for the period of two years. It is conducted to evaluate the direct and short duration interruption costs resulting from local random electrical supply interruptions. The cost is evaluated by providing a designed questionnaire focused on the experience or the preparative actions which consumers predicted they would take. In the first phase, authors made a survey on all types of industry with 176 industrial customers and evaluated them as per standard industry classification (SIC). In that case, the evaluation data obtained are not so reasonable, because the number of sampled industries was small and the sampled industries were surveyed by being divided into 18 types. So, in the second phase the authors concentrated on only 4 types of 302 industries who have many and large sensitive loads to the short duration interruption.

• 대한안전경영과학회지
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• 제10권3호
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• pp.35-41
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• 2008

It is a fact that domestic performance art has been sharply progressed but it is focused on only performance quality technique, not on safety of performers and the audience. It is a pity that people's effort to keep safe stage environment have not traced to innovative change, eventually leading to be forced to perform under hazardous condition. This study is to find out and identify that domestic regulation and accident cases are investigated and compared with cases of advanced countries, to verify that performer and the audience are main elements to develop performance art. And it is to show more effective safety measure after pointing out hazardous elements. Research change is limited to review only performance ones of all cultural facilities and to review accident cases from these places to show reasonable safety measures for stage facilities. Operation manager covers almost all of areas such as devices, management, despite a fact that they take charge of stage facilities, illumination, sounds, already. Some conclusions are as follows; 1) performance theatre-related regulations should be established again. domestic safety standards for performance theatre safety should be established. 2) characteristic and purpose of performance place should be clarified at the stage planning and design of them 3) operation expert performance place is required to be trained to cover emergency situation at any time.

• International Journal of Aeronautical and Space Sciences
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• 제10권2호
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• pp.77-85
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• 2009

A two-dimensional cross-section analysis program based on the finite element method has been developed for composite blades with arbitrary cross-section profiles and material distributions. The modulus weighted approach is used to take into account the non-homogeneous material characteristics of advanced blades. The CLPT (Classical Lamination Plate Theory) is applied to obtain the effective moduli of the composite laminate. The location of shear center for any given cross-sections are determined according to the Trefftz' definition while the torsion constants are obtained using the St. Venant torsion theory. A series of benchmark examples for beams with various cross-sections are illustrated to show the accuracy of the developed cross-section analysis program. The cross section cases include thin-walled C-channel, I-beam, single-cell box, NACA0012 airfoil, and KARI small-scale blades. Overall, a reasonable correlation is obtained in comparison with experiments or finite element analysis results.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1164-1171
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• 2010

Korea is considered to be a seasonal frozen soil area that is thawed in the spring, and most of the area is frozen in winter as to the characteristic of geography. In the current design codes for anti-freezing layer, the thickness of anti freezing layer is calculated by freezing depth against the temperature condition. Therefore, they have a tendency of over-design and uniform thickness without the considerations of thermal stability, bearing capacity and frost susceptibility of materials. So, it is essential for studying the appropriateness and bearing capacity besides the seasonal and mechanical properties of pavement materials to take a appropriate and reasonable design of the road structure. In this research, the evaluation of frost susceptibility on subgrade, ant-freezing layer, sub base was conducted by means of the mechanical property test and laboratory field road model downed scale experiment. The temperature, heaving amount, heaving pressure and unfrozen water contents of soil samples, the subgrade, anti-freezing layer, sub base soils of highway construction site, were measured to determine the frost susceptibility.

• Advances in concrete construction
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• 제9권6호
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• pp.597-610
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• 2020

Stress-strain models of fibre reinforced polymer (FRP) confined concrete have been widely investigated; however, the existing load which is always supported by structures during the retrofitting phase, namely 'preload', has been neglected. Thus, preload effects should be clarified, providing insightful information for FRP retrofitting of structures with preload conditions. Towards this aim, experiments were performed for 27 cylinder concrete specimens with the diameter 150 mm and the height 300 mm. Three specimens were used to test the compressive strength of concrete to compute the preloads 20%, 30% and 40% of the average strength of these specimens. Other 24 specimens were divided into 2 groups; each group included 4 subgroups. Four subgroups were subjected to the above preloads and no preload, and were then wrapped by 2 FRP layers. Similar designation is applied to group 2, but wrapped by 3 FRP layers. All specimens were tested under axial compression to failure. Explosive failure is found to be the characteristic of specimens wrapped by FRP. Experimental results indicated that the preload decreases 12-13% the elastic and second stiffness of concrete specimens wrapped by 2 FRP layers. The stiffness reduction can be mitigated by the increase of FRP layers. Preload negligibly reduces the ultimate force and unclearly affects the ultimate displacement probably due to complicated cracks developed in concrete. A mechanism of preload effects is presented in the paper. Finally, to take into account preload effects, a modification of the widely used model of un-preload FRP confined concrete is proposed and the modified model demonstrated with a reasonable accuracy.

• 한국정보처리학회논문지
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• 제6권12호
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• pp.3703-3709
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• 1999

본 논문에서는 영상의 밝기 정보로부터 물체의 표면 형상을 재구성하는 새로운 접근 방법을 제시한다. 표면 재구성 문제를 최적화 문제로 정의하고 국지 해(local minima)에 빠지기 쉬운 기존의 경사법(gradient method) 대신 유전자 알고리즘(genetic algorithm)을 사용한다. 이를 위해 2차원 이미지에 적절한 유전자 표현 및 유전자 연산을 제시한다. 또한 입력 이미지를 단계별로 축소하고, 축소된 이미지에 유전자 알고리즘을 적용하여 큰 형상을 먼저 결정한 후 미세한 형상을 찾아내는 계층적 방법을 적용함으로써 유전자 알고리즘의 수렴 속도를 개선한다. 반사 모델로 기존의 람버션 반사 모델(Lambertian illumination model)에 거리 요소를 포함시켜 보다 현실과 비슷한 제약 조건을 주었으며 실험을 통해 제시된 방법의 타당성을 보인다.