• 구강회복응용과학지
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• 제32권3호
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• pp.255-262
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• 2016

본 증례는 심미적, 기능적 상실을 동반하여 심하게 마모가 진행된 환자의 치료에 중점을 둔다. 장기간의 구치부 지지 상실은 포괄적인 보철 수복을 요한다. 정확한 임상적 및 방사선학적 검사, 진단 납형 제작, 수직 고경 평가 후, 임시 수복물을 통해 환자의 적응도를 평가하였다. 8주간의 관찰기간 후에, 별다른 이상이 발견되지 않아, 최종 수복물을 제작하였다. 최종 수복물 장착 6개월 후에도 만족스런 기능적, 심미적 결과를 얻을 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.171-175
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• 2001

Chemical mechanical polishing(CMP) process has been widely used to planarize dielectrics and metal, which can apply to employed in integrated circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of free-defects in inter level dielectrics and metal. Especially, defects like (micro-scratch) lead to severe circuit failure, and affects yield. Current conditioning method - bladder type, orbital pad motion - usually provides unsuitable pad profile during ex-situ conditioning near the end of pad life. Since much of the pad wear occurs by the mechanism of bladder tripe conditioning and its orbital motion without rotation, we need to implement new ex-situ conditioner which can prevent abnormal regional force on pad caused by bladder-type and also need to rotate the pad during conditioning. Another important study of ADPC is related to the orbital scratch of which source is assumed as diamond grit dropped from the strip during ex-situ conditioning. Scratch from diamond grit damaged wafer severely so usual1y scraped. Figure 1 shows the typical shape of scratch damaged from diamond. We suspected that intensive forces to the edge area of bladder type stripper accelerated the drop of Diamond grit during conditioning, so new designed Flat stripper was introduced.

• 센서학회지
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• 제31권6호
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• pp.433-440
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• 2022

Recently, owing to global warming, average summer temperatures are increasing and the number of hot days is increasing is increasing, which leads to an increase in heat stroke. In particular, outdoor workers directly exposed to the heat are at higher risk of heat stroke; therefore, preventing heat-related illnesses and managing safety have become important. Although various wearable devices have been developed to prevent heat stroke for outdoor workers, applying various sensors to the safety helmets that workers must wear is an excellent alternative. In this study, we developed a smart helmet that measures various vital signs of the wearer such as body temperature, heart rate, and sweat rate; external environmental signals such as temperature and humidity; and movement signals of the wearer such as roll and pitch angles. The smart helmet can acquire the various data by connecting with a smartphone application. Environmental data can check the status of heat wave advisory, and the individual vital signs can monitor the health of workers. In addition, we developed an algorithm that classifies the risk of heat-related illness as normal and abnormal by inputting a set of vital signs of the wearer using a support vector machine technique, which is a machine learning technique that allows for rapid binary classification with high reliability. Furthermore, the classified results suggest that the safety manager can supervise the prevention of heat stroke by receiving feedback from the control system.

• 한국축산시설환경학회지
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• 제12권1호
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• pp.21-28
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• 2006

국민의 소득 증대로 인해 육류 및 계란의 소비량이 점차적으로 증가하는 추세에 있다. 이로 인해 산란계사의 규모가 대형화됨에 따라 기계화되었고, 이 연구에서는 고단 직립식 케이지를 사용하는 무창계사에서 기계시설이 작동 시 발생되는 소음 및 진동이 산란계의 생산성에 미치는 영향을 구명하고자 산란계사내의 소음/진동 수준을 측정 분석하였다. 전국의 13개 산란계 농장을 대상으로 하여 평상시 및 기계시설(사료급이기, 사료분배기, 집란시스템, 환기장치, 계분벨트)의 작동시에 발생되는 소음/진동을 측정하였다. (1) 평상시 소음 최대 82dB, 진동 최대 0.2072 cm/s, (2) 사료급이기 작동 시 소음 최대 90dB, 최대 진동 2.8560cm/s, (3) 사료분배기 작동시 소음 최대 90dB, 최대 진동 2.022cm/s, (4) 집란시스템 작동 시 최대 소음 87dB, 최대 진동 0.1865cm/s, (5) 환기장치 작동 시 케이지에 미치는 최대 88dB, 계사 후면 벽면에 미치는 최대 진동 2.5364cm/s, (6) 계분벨트 작동 시 최대 소음 88dB, 최대 진동 0.2387cm/s 이었다. 따라서 산란계에게 직접적이고 가장 크게 영향을 미치는 장치는 급이 시스템이였다. 이 때의 소음은 최대 90dB로 가장 높게 발생하였으며, 진동은 최대 2.8560 cm/s 발생하였다.

• Journal of Chest Surgery
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• 제23권4호
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• pp.617-621
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• 1990

A heart supplies blood of about 15, 000 liters to each human organ in a day. A normal function of heart valves is necessary to accomplish these enormous work of heart. The disease of heart valve develops to a narrowness of a closure, resulting in an abnormal circulation of blood. In an attempt to eliminate the affliction of heart valves, the operative method to replace with artificial heart valves has developed and saved numerous patients over past 30 years. This replacement operation has been performed since early 1960`s in Korea, but all the artificial heart valves used are imported from abroad with very high costs until recent years. New artificial heart valves have been developed in Korea Advanced Institute of Science and Technology since early 1980`s. The first developed valve was designed with a free-floating pyrolytic carbon disk that is suspended in a titanium cage. The design of the valve was tested in vitro, and in animals in 1987. The results from this study was that the eccentrically placed struts creates a major and minor orifice when the disc opens and stagnation of flow in the area of the minor orifice has led to valve thrombosis. In this work, the design of the valve was changed from a single - leaflet valve to double - leaflet one in order to resolve the problems observed in the first - year tests. Morphological and hemodynamic studies were made for the newly designed valves through the in vitro and in vivo tests. The design and partial materials of the artificial heart valve was improved comparing with first - year`s model. The disc in the valve was modified from single - leaflet to bi - leaflet, and the material of the cage was changed from titanium metal to silicon - alloyed pyrolytic carbon. A test was made for the valve in order to examine its mechanical performance and stability. Morphological and hemodynamic studies were made for the valve that had been implanted in tricuspid position of mongrel dogs. All the test animals were observed just before the deaths. A new artificial heart valve was designed and fabricated in order to resolve the problems observed in the old model. The new valve was verified to have good stability and high resistance to wear through the performance tests. The hemodynamic properties of the valve after implantation were also estimated to be good in animal tests. Therefore, the results suggest that the newly designed valve in this work has a good quality in view of the biocompatibility. However, valve thrombosis on valve leaflets and annulus were found. This morphological findings were in accordance with results of surface polishing status studies, indicating that a technique of fine polishing of the surface is necessary to develop a valve with higher quality and performance.