방사선사진의 인덱스-순서 분석을 통한 치아경조직의 탈염화 검출

박동현,박영호,김경숙,박정훈,이기자,최삼진,최용석,황의환,박헌국 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.2

Purpose : The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries. Materials and Methods : This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. Results : We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. Conclusion : Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.

중ㆍ고등학생들의 수학교과 호오도(好惡度)의 변화에 대한 분석

박규홍,박기양,김영국,박윤범,박혜숙,임재훈 서원대학교 교육대학원 2000 교육논총 Vol.4 No.-

In this paper we investigate and analyze the variation of secondary school student's like and dislike the school mathematics lesson. First, we investigate the reason that why students dislike mathematics in the class and we search the point of time when the students dislike mathematics in the class. Next, we investigate and analyze the variation of student's inclination to the school mathematics lesson. In this research we try the followings. 1) We analyze the variation of each level school, student's inclination to the school mathematics class, 2) We analyze the variation of student's inclination to the mathematics for each place where the school located. 3) We analyze and compare between the inclination to the mathematics lesson and to each level school. 4) We analyze and compare between the inclination to the mathematics lesson and to each factors of student's inclination From these investigation and analysis, we have the following conclusion . (1) The student's inclination to the mathematics is depend on the teacher's teaching method and on the fact that how can the mathematics lesson be composed easily. (2) The student's response was seen in the same type from the inquiry about the inclination to the mathematics lesson in the school of Seoul and small country town. This is a passing phase caused by the educational environment in Seoul and the small country town's schools is better than that of the big city or medium city. (3) The student group of the human knowledge in the general high school show the negative response for the inclination to the matheirlatics lessen compare to that of the student group of natural science in the general high school. (4) In the middle school, about half of the students dislike mathematics But such dislike rate of mathematics increased in the high school. (5) Teachers must take into consideration to the student in the first grade high school mathematics course To do this, teachers make adapt the curriculum easily for the student and must teach the mathematics to the students who can take interest in the mathematics.

인공 치아우식 발생 모델에서 디지털 방사선 공제술을 이용한 인접면 치아우식증의 진단

박정훈,최용석,황의환,이기자,최삼진,박영호,김경숙,진현석,홍경원,오범석,박헌국 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.1

Purpose : The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Materials and Methods : Digital radiographies of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size #2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. Results : In artificial caries activity model, the range of lesional depth was 572-1,374 μm and the range of lesional area was 36.95-138.52mm². The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. Conclusion : The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

울산하수처리장의 화학적인 수질개선

박흥석,조영국 울산대학교 1997 공학연구논문집 Vol.28 No.1

본 연구의 목적은 1차 처리를 하는 울산하수처리장을 화학적 응집제의 첨가로 수질을 개선하는 것이었다. 설계당시의 BOD, COD 및 SS의 제거효율은 40 ∼ 60%이었으나 현재의 제거효율은 30∼40% 이다. 그러나 설계당시 고려되지 않았던 총질소와 총인의 제거율은 각각 30%, 3%이었다. 소량의 응집제 Hi-PAX(Poly Aluminum Chloride Silicate)를 펌프동 유입부에 주입하여 모든 항목에서 오염물의 제거율이 향상되었다. 또한 총질소의 제거효율은 3%에서 30%로 총인의 제거효율은 30%에서 90%로 증가하였다. 종합적인 오염인자인 OCP(Oxygen Consumption Potential)는 기존 1차 침전공정은 전체 오염물의 15%정도만 제거할 수 있으며 생물학적 처리는 39%, 그리고 화학적 처리는 50%내외로 처리되는 것으로 나타났다. OCP 1kg 를 처리하는데 소요되는 단위처리비용은 기존 1차 처리 공정의 33%, 1차처리후 생물학적 처리할 경우의 75% 수준이었다. The objective of this study was to upgrade the efficiencies of Ulsan primary municipal wastewater treatment plant by chemical application. The present removal efficiencies of BOD, COD and SS were in the range of 30 ∼ 40% while the design target were 40∼60%. But the removal of total nitrogen and phosphorous, which components were not considered at the time of design, were 30 % and 3 %, respectively. The simple application of small amount of Hi-PaX(Poly Aluminum Chloride Silicate) to the inlet of screw pump shows enhanced removal efficiencies in all contaminants. The removal of SS increased to 80 ∼ 90% while BOD and COD to 70% and 55%, respectively. In addition, the removal of total nitrogen and phosphorous removal also increased from 3% and 25% to 30% and 90%, respectively. The removal of integrated pollution parameter OCP(Oxygen Consumption Potential) in present primary treatment was 15%, 39% in biological treatment after primary treatment and about 50% in chemical treatment. the unit cost of OCP removal in chemical treatment was 33% of that of present primary process, 75% of that of biological treatment after present process.

첨단 수송장비용 센서 및 응용시스템 개발

朴世光,崔時永,全國鎭,李光萬 경북대학교 센서기술연구소 1997 연차보고서 Vol.1997 No.-

자동차의 안전성 향상과 편리성은 정밀한 기계적 시스템과 첨단 전자 시스템의 조화에 의한 것이다. 현재 자동차의 전자 시스템 중 엔진의 고효율을 위해 엔진유입 공기량, 실린더의 압력, 엔진의 회전수 등을 검출하는 센서부와 사고의 원인인 타이어 펑크를 모니터링하는 시스템이 첨단 수송 장비의 핵심 부품이다. 따라서 이를 개발하기 위해서 1) 자동차용 Air Flow Sensor, 2) 자동차용 엔진 MAP Sensor, 3) 멀터센서 모니터링 시스템, 4) 자동차 실내 환경제어용 센서시스템 개발을 위한 연구를 수행하였다. 자동차용 엔진 공기유량센서를 제작하기 위해서 유한차분법과 SPICE로 시뮬레이션을 수행하고 이 결과로 센서를 설계하였다. 센서의 저항체를 제작하기 위해서 백금박막을 제작하고 각각 조건별로 특성을 조사하여 패터닝이 잘되고 저항값이 크고 온도계수가 큰 조건을 선택하여 센서를 제작하였다. 센서는 lift-off법으로 백금을 패터닝하고 PI-2723을 보호막으로 사용하였다. 구동회로는 정온도형으로 동작하도록 피이드백 회로를 사용하였고, 기준유량계 출력과 일치하도록 피이드백 회로의 출력전압을 증폭하였다. 유체의 온도와 유량을 변화시킬 수 있는 실험장비를 제작하고 기준유량계와 제작한 유량계의 출력을 동시 측정하여 실험결과를 비교하였다. 유량에 대한 실험에서는 증폭한 출력전압은 기준유량계 출력과 거의 일치하였고, 스텝응답과 과도응답에서도 기준유량계 출력과 거의 일치함을 보았다. 자동차용 엔진 MAP Sensor의 연구에서는 SDB 웨이퍼를 이용하여 절대압 압력센서를 제조하였다. 센서의 구조는 두 개의 휫스톤 브릿지 회로와 다이아프램으로 구성되어있다. 두 개의 휫스톤 브릿지중 하나는 다이아프램의 가장자리에 위치하고, 다른 하나는 다이아프램의 가운데 부분에 위치한다. 다이아프램의 공극은 10^-5 Torr의 진공에서 형성시켜 공극안의 공기로 인한 압력센서의 감도에 미치는 온도효과를 줄였다. 이것은 압력센서의 온도보상에 대한 부수적인 방법이다. 본 실험의 주된 온도 보상법은 두 브릿지의 오프셋 전압의 차를 이용한 방법이다. 이 방법을 이용하여 22 ∼ 100℃ 범위에서 온도 영향을 80 %이상 보상할 수가 있었다. 멀티센서 모니터링 시스템 연구에서는 첨단 수송장치용에 적합한 직접 디지털 출력을 갖는 압력 센서와 온도 센서를 멀티 센서에 적합한 형태로 제작하였다. 압력 센서는 PR 희생층과 금속 구조층으로 하는 표면 마이크로머시닝 기술을 이용하여 제작하였으며, 온도 센서는 n-well CMOS 공정을 이용한 substrate PNP BJT 트랜지스터를 이용하여 제작하였다. 이 두 센서를 함께 제작할 수 있는 공정을 개발하였으며 각각소자에 대하여 측정 셋업을 구성하여 측정하였다. 직접 디지털 압력 센서의 출력에 대한 기본적인 동작 특성을 확인하였으며, 제작된 온도 센서의 감도는 1.57 ㎷/℃ 이다. 자동차 실내환경제어용 센서시스템 개발에서는 표준 CMOS 공정기술과 실리콘미세가공기술을 이용하여 자동차 실내환경 제어용 센서시스템을 개발하기 위하여 마이크로 가스유량센서와 습도센서를 설계하고 제조공정을 수행하였다. 가스유량센서의 경우 설계된 칩의 크기는 3 × 3 ㎟이고, 히터 좌우에 6 쌍의 n-poly/p-poly 열전대를 구성하였다. 습도센서의 경우 칩의 크기가 0.8 × 1.2 ㎟이고 단일 n-poly 실리콘히터로만 구성되어 있는 매우 간단한 구조를 하고 있다. 최소의 열용량과 기판 및 페케지를 통한 열손실을 최소화하기 위하여 열적 및 기계적 특성이 우수한 NON 구조의 브릿지형 다이아프램을 실리콘 미세가공 기술을 이용하여 구현하였다. 또한 NON절연막의 열전도특성을 연구하기 위한 측정소자를 설계·제작하고 그 특성을 측정 중에 있다. 마이크로 습도센서의 동작원리를 기술하고 마이크로 열센서를 구동하게 될 구동회로를 설계·검증하고 있으며 CMOS 회로화 하여 센서와 함께 집적된 센서시스템을 구현할 것이다. The improvement of safety and convenience in motor car lies on the harmony of a minute mechanical system and high-tech electric system. Nowadays the core part of the high-tech transport equipment is the system and the sensor part. The system monitors the flat tire that causes accidents and the sensor part detects the air amount of a engine intake, the pressure of the cylinder and the turn number of an engine for high efficiency of engine in car electronic system. In order to develop it, therefore we have studied 1) an air flow sensor for car engine, 2) a pressure sensor for car engine, 3) the system monitoring pressure of car tire. We designed air flow sensor in use of a finite different method and SPICE simulation to make it. In order to make resistors in the sensor, we made platinum thin film and then we tested the characteristics of the thin film in various conditions. So we chose the condition which is patterning better, higher resistor value and higher temperature coefficient. The sensor of platinum thin film was patterned by lift-off method and passivated with PI-2723. We used the feedback circuit to make an operation circuit drive in constant temperature. We amplified the output voltage of the fabricated sensor in accordance with that of a reference flowmeter. We made an equipment to change fluid temperature and flow. We measured the output of the reference flowmeter and the fabricated flow sensor simultaneously, and compared them. In the experiment, the amplified output voltage nearly agree to the output of the reference flowmeter. The absolute pressure sensor using SDB wafer has been fabricated. The structure of the sensor consists of two Wheatstone bridges and a diaphragm. One of the two Wheatstone bridges is located on the edge of diaphragm, and the other is located on the center of diaphragm. The diaphragm cavity is sealed in vacuum(∼10^-5 Torr) to reduce the effect of temperature due to the vapor in the cavity on the sensitivity of pressure sensor. This is the minor method of temperature compensation method. In this experiment the main compensation method is to use the differrence of the two bridge offset voltages. In this method the temperature effect in the range of 22 ℃ ∼ 100 ℃ was compensated over 80 %. We produced a pressure sensor and a temperature sensor, which are suitable for a multi sensor, and have the direct digital output suitable for an advanced transporting equipment. The pressure sensor was fabricated using a surface micromachining technique with a sacrificial PR layer and a structural metal layer. The temperature sensor was fabricated using a substrate PNP BJT made by use of an n-well CMOS process. We developed the process that could produce these two sensors together, organized and estimated the setup about each element. The basic operating characteristics are identified about the direct digital output of the pressure sensor, and the sensitivity of the produced temperature sensor is 1.57㎷/℃ Micro gas-flow sensor and humidity sensor were designed and fabricated using a standard CMOS process technology and silicon micromachining techniques for an Interior Environment of Automotive. The chip size of designed gas-flow sensor is 3 × 3 ㎟ with six pairs of n-poly/p-poly thermocouples around the heater. For the case of the humidity sensor, the size is 0.8 × 1.2 ㎟ with single n-poly silicon heater and simplicity. A bridge type diaphragm of NON structure having an excellent mechanical and thermal properties, was implemented by silicon anisotropic etch. The thermal properties of NON insulator is investigating using by the measurement device that was designed and made specially. The operating principle of micro humidity sensor was described and the driving circuits of the micro thermal sensors were designed and verified. The circuits in CMOS will be integrated into the sensor system with the thermal sensor.

발육중인 생쥐 하악 과두에서 연골 및 골의 특이 유전자 발현

지국섭,윤영주,박주철,김광원 대한치과교정학회 2004 대한치과교정학회지 Vol.34 No.2

하악과두 연골이 발생하고 분화하는 과정에서 나타내는 특성을 규명하기 위하여, 발생 16, 18일과 출생 1일, 5일, 10일, 20일 및 30일 후의 ICR생쥐의 하악과두를 형태학적으로 분석하고, 생쥐 Ⅰ형, Ⅱ형, X형 교원질, Indian hedgehog(IHH) 및 BMP-4 등의 mRNA 발현을 in-situ hybridization 방법으로 연구하였다. 1. 생쥐 Ⅰ형 및 Ⅱ형 교원질 mRNA는 하악과두의 발생 및 성장과정에서 모두 발현되었다. Ⅰ형 교원질 mRNA는 휴지층과 증식층의 상부에서 관찰된 반면 Ⅱ형 교원질은 휴지층과 증식층 그리고 비대연골층의 상부에서 관찰되었다. 2. 하악과두 연골은 성장에 따라 비대연골층이 계속 증가하는 소견을 보였으며, 비대 연골층의 세포들은 특징적으로 X형 교원질 mRNA의 발현을 보였다. 3. BMP-4 mRNA는 하악과두 연골 원기와 골화중인 하악골체에서 모두 발현되었다. 4. IHH mRNA는 하악과두의 발생과정에서 증식 연골층의 하부와 비대연골층의 상부에서 선택적으로 관찰되었다. It has not been elucidated whether the initiation of condylar development of the mandible is related with the periosteum of the mandible, or if it derives from a separate programmed blastema not related with the mandible. Also, although the mandibular condylar cartilage is known to promote growth, few studies have dealt with molecular-biologic mechanisms such as the expression of specific genes according to the differentiation of the mandibular condyle. To elucidate the unique cellular characteristics, development, and differentiation process of the mandibular condyle, an examination of expressions of genes characteristic of cartilage and bone were carried out using RT-PCR and mRNA in situ hybridization. 1. Type?collagen mRNA was detected with type Ⅱ collagen mRNA in the differentiation and growth process of the cartilage of the mandibular condyle. Type Ⅱ collagen mRNA was demonstrated in the whole resting and upper part of the proliferative zone, whereas type Ⅱ collgen mRNA was observed in the resting, proliferative and upper hypertrophic cartilage zone of the mandibular condyle. 2. The condylar cartilage rapidly increased in size due to the accumulation of hypertrophic chondrocytes as characterized by the expression of type Ⅱ collagen mRNA during postnatal development. 3. BMP-4 mRNA was present in the anlage of the future condylar process and also in the ossifying mandibular body. 4. IHH mRNA was limited exclusively to the lower part of the proliferative zone and the upper part of the hypertrophic cartilage zone during condylar development. These findings were different from those in the growth-plate cartilage of the long bone, indicating a characteristic feature of the differentiation of the chondrocytes in the condylar cartilage present in prenatal and postnatal development. Furthermore, it was also suggested that chondroblasts of condylar cartilage rapidly differentiate into hypertrophic chondrocytes with increased functional Load force such as muscle activity and mastication.

폐흡충증으로 확진된 고립성 폐결절 1예

유영권,김규식,김윤현,나국주,김경수,임성철,김영철,박경옥 全南大醫大 2001 전남의대학술지 Vol.37 No.2

성장발육에 따른 흰쥐의 악관절 신경분포의 변화

배용철,김영진,박국필,김현정,남순현 大韓小兒齒科學會 1999 大韓小兒齒科學會誌 Vol.26 No.1

The purpose of this study was to investigate the distribution of CGRP immunoreactive nerve fibers in rat squamosomandibular joint with postnatal development. Squamosomandibular joint with adjacent tissue of 8 groups of rats(1,5,10,15,20,25,35-postnatal day and adult groups) were removed en bloc and processed for immunohistochemistry and were subjected to light microscopic examination. The results obtained were as follows; 1. The anterior portion of the articular disk was most densely innervated, followed by the posterior, lateral, and medial portions in each group. 2. Increase of CGRP immunoreactive nerve fibers was evident in 10,15,20 postnatal day groups. 3. Almost no CGRP immunoreactive nerve fibers were observed in articular surface of disk proper, mandibular fossa and condyle head of each group. These result suggest that CGRP immunoreactive nerve fibers increased in synovial membrane and peripheral portion of articular disk during 10-20 postnatal day may play a important role in squamosomandibular joint function after weaning period.

人蔘이 卵巢摘出로 誘發된 흰쥐의 骨多孔症 예방에 미치는 효능

정국영,서부일,이은숙,변부형,신순식,박지하 대한본초학회 2004 大韓本草學會誌 Vol.19 No.1

Objectives : The present study has been undertaken to investigate the effects of Ginseng Radix on prevention of osteoporosis in ovariectomized rats. Methods : In this experiment, the rats were ovariectomized. Rats were administered by 2 kinds of medicine, Estradiol, Ginseng Radix. The levels of bone mineral density, osteocalcin, ALP, phosphorus, calcium in serum, deoxypyridinoline in urine, calcium, phosphorus, ash weight of bone, body weight and uterus weight were measured. Results : The levels of spinal bone mineral density was significantly increased in comparison with OVX group at 8 weeks in Ginseng Radix group. The levels of serum didn t show significant change in comparison with OVX group in Ginseng Radix group. The levels of urine deoxypyridinoline showed significant decrease in comparison with OVX group in Ginseng Radix group. The levels of femoral and fibula-tibial ash weight didn t show significant increase in comparison with OVX group in Ginseng Radix group. The levels of femoral and fibula-tibial calcium showed significant increase in comparison with OVX group in Ginseng Radix group. The levels of femoral and fibula-tibial phosphorus showed significant increase in comparison with OVX group in Ginseng Radix group. The levels of body weight didn t show significant changes in comparison with OVX group in Ginseng Radix group. The levels of uterus weight didn t show significant changes in comparison with OVX group in Ginseng Radix group. Conclusions : Reviewing these experimetal results, it appears that Ginseng Radix have efficacy on prevention of osteoporosis. And further study should be conducted to illustrate in depth the curing and prevention of osteoprosis.

가열로의 열적해석 및 설계인자에 관한 연구

서용석,강성규,박원희,민동호,김태국 중앙대학교 기술과학연구소 1998 기술과학연구소 논문집 Vol.28 No.-

본 연구에서는 3차원 정육면체 가열로 내의 전도-대류-복사 복합열전달 특서을 해석하였으며, 연소가스의 유입속도, 벽면의 반사율과 매체의 흡수계수 등과 같은 인자들의 변화에 따른 영향을 살펴보았다. 가열로의 벽면들은 단열되어 있고 가열로 내부로 일정한 온도의 연소가스가 유입될 때 시스템 내부의 온도는 유입 온도와 비슷하게 균일한 온도 분포를 갖는 것으로 예측할 수 있었다. 유입 속도가 증가하더라도 가열로 내부의 온도에는 거의 영향을 미치지 않았으며, 가열로는 유입되는 연소가스의 흡수계수가 증가할수록 가열로 내부의 온도는 보다 균일하게 된다. 또한, 가열로 내부 벽의 반사율이 커질수록 벽의 온도는 감소하고 또한 벽면에 작용하는 유효복사열유속은 증가함을 알 수 있었다. 이러한 해석 결과로부터 가열로 내부의 온도 분포는 매체의 흡수계수가 클수록 그리고, 벽면 반사율이 작을수록 일정하게 유지될 수 있다는 것을 알 수 있었다. 그리고 이러한 결과들을 종합하여 볼 때 가열로의 설계 시 일정한 열의 유입과 가열로를 단열시키는 것이 중요하며, 그리고 매체의 흡수 계수를 크게 하고, 그리고 벽면의 반사율을 작게 하는 것은 가열로 내부의 온도를 일정하게 유지할 수 있는 중요한 조건이 된다는 것을 알 수가 있었다.