• 대한치과교정학회지
• /
• 제44권3호
• /
• pp.143-153
• /
• 2014

An 8-years old boy with facial asymmetry and unilateral posterior crossbite on the left side received orthopedic and orthodontic treatment. During the first phase of treatment, the narrow maxillary arch was expanded using an acrylic plate. Then, the acrylic plate was used as a bite block with occlusal indentations from the construction bite that was obtained with the incisors in a coincident dental midline. After the position of the mandible was stabilized, the second phase of orthodontic treatment was initiated using fixed appliances for detailing of the occlusion. Skeletal symmetry, ideal occlusion, and coincident dental midlines were thus achieved. Functionally, occlusal force balance and masticatory muscle activity were improved, and the chewing patterns were normalized.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2001년도 추계학술대회논문집 I
• /
• pp.349-353
• /
• 2001

An air foil bearing is developed for the high speed generator. The bearing is type of multi-leaf and is stable on 60,000RPM. The vibration level is 12um(p-p) and the highest temperature level is below 100$^{\circ}C$. The dynamic parameter of air foil bearing is acquired by experimental method using exciter. The air foil bearing is also good condition at test of real generator and load condition. The condition of foil is very good after 3,000cycle start-stop test. Therefore the air foil bearing is ideal for high speed, light weight and modem turbo-machinery.

• 대한기계학회논문집B
• /
• 제27권9호
• /
• pp.1238-1247
• /
• 2003

Simplified thermodynamic analysis of high pressure 4-stage reciprocating compressors with 4 inter-coolers has been investigated to predict a behavior of a compressor system for NGV(natural gas vehicles). A computer program has been developed to predict and estimate the performance of high pressure 4-stage reciprocating compressor system. Thermodynamic properties of compressed natural gas(CNG) were calculated by ideal gas theory and compression cycle was assumed as reversible adiabatic compression and expansion processes, and isobaric intake and discharge processes. Comparison between results predicted by calculation model and measured by experimental tests is presented.

• 설비공학논문집
• /
• 제18권12호
• /
• pp.964-970
• /
• 2006

Vapor compression refrigerators have much critical variables such as the controls of temperature and pressure switches, control durations and operating hours of electronic valves. This study compares and analyzes the data which is obtained from system controlling of the evaporation temperatures which are generally used in automatic pump down operating systems. Through this study, the automatic evaporation control operation system will be more ideal for the system to keep the proper temperature distribution depending on the purpose of evaporation side. The automatic pump down control operation is more appropriate for the system to aim at the effective use of evaporation side without using the temperature difference. And this test will be proved that the changes at the low pressure side didn't have significant impacts on the high pressure side.

• 한국군사과학기술학회지
• /
• 제14권6호
• /
• pp.1178-1185
• /
• 2011

In the present study, a recuperator is suggested to improve the thermal efficiency of a micro gas turbine. Primary design parameters of the recuperator are determined from the ideal cycle analysis. The counter flow plate-fin heat exchanger with offset strip fins is chosen as the type of the recuperator. In order to satisfy the design constraints which are the minimum effectiveness and the maximum pressure drop, the optimization for the internal structure of the recuperator is performed with varying the fin spacing and the fin height of offset strip fins. Also the effects of the thermal conductivity of fins and separation plates and the longitudinal heat conduction on the thermal performance of the recuperator are investigated.

• 오토저널
• /
• 제4권2호
• /
• pp.58-68
• /
• 1982

It is well known to diesel engineers that the heat release pattern is one of the most important factors affecting engine performance. Thorough research in heat release pattern has materially helped the progress in high-speed diesel engine development . This paper is based on the research conducted at KAIST and Daewoo Heavy Industry last year. The purpose of this paper is to determine the heat release pattern in combustion chamber of MAN M type, the famous low-noise engine. Thermodynamic cycle simulation was performed using Whitehous-Way's heat release pattern with modified coefficients and Annand's heat transfer model. Instantaneous temperature and pressure of gas in cylinder could be determined by the numerical solution of simultaneous equation of mass conservation, equation of energy conservation, and state equation of ideal gas. Calculated results were compared with measured values in some details emphasizing upon the factors affecting rate of heat release. The agreement was fairly good and revealed why M type should have lower burning velocity at the early part of combustion in spite of high injection rate. Additional results by parametric studies were given in relation to fuel injection conditions for further application to engine development.

• 설비공학논문집
• /
• 제7권1호
• /
• pp.150-160
• /
• 1995

A Finkelstein adiabatic analysis is performed for Stirling refrigerator with real gas properties of helium. The mass balance and the energy balance equations are formulated into the form that is convenient for incorporating an available computer code of the helium properties. The differential equations are solved numerically. The calculated coefficient of performance(COP) and the pressure variation are compared with the results obtained when helium is assumed to be an ideal gas. The relative errors in COP are presented as functions of the refrigeration temperature and the maximum cycle pressure.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
• /
• pp.2015-2020
• /
• 2011

Key set the current non-urban rail power failure of equipment to operate the railway will generate a lot of problems. I know in advance the ideal of power equipment to prevent the failure to derive an efficient replacement cycle for the power equipment monitoring and diagnosis of the condition can become necessary to develop a system. In order to determine the status of the power plant during operation and behavior of the partial discharge current state data, regular monitoring and inspection requirements also stamp the basic current, voltage, temperature and humidity should be identified.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 제38회 하계학술대회
• /
• pp.1365-1366
• /
• 2007

Cobalt oxide was composite with MWNT to attain cycle stable by chemical method. We have been considered CoOx is the ideal material for high energy density electrochemical capacitor due to pseudo capacitor reaction. In this study we found that decrease in resistance due to composite MWNT. Also CoOx/MWNT composite material have resulted larger capacitance and exhibits better electrochemical behavior. The structural feature was investigated by using SEM. The CoOx/MWNT composite is not only a promising ultracapacitor material for energy storages but also has a good possibility because of its great capacitive properties, simple preparation and low cost.

• 구강회복응용과학지
• /
• 제38권1호
• /
• pp.60-68
• /
• 2022

심한 치주염을 가진 환자는 잔존 치조골의 흡수가 증가함에 따라, 병적인 치아 이동이 증가하고 구치부 교합지지 상실의 가능성이 높다. 특히, 상악 전치부에서 병적인 치아 이동이 발생하는 경우, 환자는 심미적인 위축감과 삶의 질 저하를 경험할 수 있다. 중증 치주염 환자에게 교정치료는 새로운 뼈 형성을 촉진하고 치주낭을 감소시키며, 임상적 부착을 얻어 보철 수복에 유리한 결과를 가져옴으로써 이상적인 교합과 기능 회복을 가능하게 한다. 구치부의 교합지지 상실로 인해 전치부 병적 치아 이동이 있는 환자에게 치주치료, 교정치료, 임플란트 치료를 계획함으로써 이상적인 수복공간 확보와 안정적인 교합접촉을 형성하였고, 구치부 교합회복을 통한 기능적인 전악수복을 통해 심미적인 결과를 얻었다.