가시광선중합화에 따른 충전용 Glass Ionomer Cement의 물리적 성질에 관한 연구

신동훈,권혁춘,Shin, Dong-Hoon,Kwon, Hyuk-Choon 대한치과보존학회 1992 Restorative Dentistry & Endodontics Vol.17 No.2

The aim of this study was to investigate the physical properties of visible light curing Glass Ionomer cement for restorative esthetic filling. The control group was the autopolymerizing GC Fuji II Glass Ionomer cement (2.2: 1 P/L ratio) and the experimental groups were made by following procedure. To induce the polymerization by visible light, the powder of GC Fuji II GI cement and the liquid of Vitrabond for base & liner were mixed in an amalgam capsule with 2.5:1, 3.0:1, 3.5:1 P/L ratio (% wt/wt). After fabrication of specimens, compressive strength, fracture toughness ($K_{IC}$) Scanning Electron Microscope and X-ray Diffraction, water-leachable content, marginal leakage and surface roughness were studied. The results were as follows: 1. Only experimental No. 1 group (visible light curing) showed less compressive strength than control group 1 hour after curing. Strength was increased with aging in all groups, so the compressive strength of light curing groups was no less than that of autopolymerizing group after 3 weeks. 2. Experimental No.3 group (visible light curing) was inferior to No.2 group (visible light curing) in fracture resistance but light curing groups were more resistant to fracture than autopolymerizing group and showed ductile fracture pattern as compared with the brittle fracture pattern of autopolymerizing group. 3. From scanning electron microscopic image, various sized unreacted powder particles, surrounded by silica gel, were embedded in polysalt matrix. Light curing groups showed little crack and more dense unreacted particles than autopolymerizing group. 4. From X-ray diffraction analysis, GC Fuji II Glass Ionomer cement powder and all groups showed glassy appearance but light curing groups seemed to be more intensive in crystaline than autopolymerizing group. S. The most significant dissolution was shown in early setting period in all group. Light curing groups were dissolved less than autopolymerizing group. 6. Marginal leakage was not different significantly in case of cavity margin composed of same tooth structure (ex. only enamel margin, only dentin margin) but much more leakage was shown in dentin/cementum margin than enamel margin. In only case of only enamel margin, light curing groups were superior to autopolymerizing group. 7. All groups showed relatively smooth surface, which irregularity was less than $1{\mu}m$. Light curing groups were smoother than autopolymerizing group.

Trichophyton rubrum의 경구용 항진균제에 대한 시험관내 감수성

신동훈,최종수,김기홍 ( Dong Hoon Shin,Jong Soo Choi,Ki Hong Kim ) 대한피부과학회 1990 大韓皮膚科學會誌 Vol.28 No.5

영팽창선이론(零膨脹線理論)에 의한 동적토압해석(動的土壓解析)

신동훈,황정규,Shin, Dong Hoon,Hwang, Jung Kyu 대한토목학회 1993 대한토목학회논문집 Vol.13 No.5

본 연구에서는 토체내에 발생하는 파괴면(破壞面)의 방향(方向)은 선형변형율증분(線形變形率增分)이 0인 영팽창선(零膨脹線)의 방향(方向)과 일치한다고 하는 Roscoe의 영팽창선이론(零膨脹線理論)과 Mononobe-Okabe의 동적(動的) 토압이론(土壓理論)을 응용(應用)하여 지진(地震)의 영향(影響)을 고려한 동적토압이론식(動的土壓理論式)을 제안하였다. 동적토압식을 유도함에 있어서 벽체는 연직이고 재하중(載荷重)이 없으며, 뒷채움면은 수평면이고 그 재료는 조밀한 비점착성(非粘着性) 사질토(砂質土)로서 지진시에도 토질정수(土質定數)는 변화되지 않는 것으로 가정하였으며, 지진에 의한 영향을 고려하기 위하여 수평방향진도(水平方向震度)만을 고려하였다. 한편, 제안된 토압식에 포함되어 있는 수평진도(水平震度), 흙의 내부마찰각(內部摩擦角), 벽마찰각(壁摩擦角) 및 다이레이션각(角)의 영향을 분석하였으며, 유도된 이론식을 Mononobe-Okabe의 토압식과 비교분석하였다. The present study was made based on the zero extension line theory and the well-known Mononobe-Okabe's to determine the dynamic earth pressures acting on the retaining walls. The zero extension line theory, which was proposed by Roscoe et al., assumes the coincidence between the loci of failure and the zero extension lines in soil mass. ln order to compute the dynamic earth pressure developed by an earthquake, it was assumed that for the vertical retaining walls with no surcharge, the backfill materials are dense and cohesionless sandy soils, there are no changes in soil parameters during earthquake, and the horizontal earthquake intensity is considered. The effects of horizontal earthquake intensity, internal friction angle of soil, wall friction angle and dilation angle, on the earth pressure coefficients were analysed. Final1y, the presented theories were successfully compared with the Mononobe-Okabe's as well.

고온환경에서의 한국인 작업능력 - 고추가 피부의 온도 및 전기저항에 미치는 영향 -

신동훈,조장제,장세구,고재평,엄륭의,Shin, Dong-Hoon,Cho, Jang-Ze,Chang, Se-Koo,Koh, Jae-Pyong,Earm, Yung-E 대한생리학회 1970 대한생리학회지 Vol.4 No.1

In order to investigate the changes in the temperature regulation mechanism following ingestion of red pepper, twenty healthy man were given 2 gms of powdered red pepper each in 100 ml of water at room temperature, $20^{\circ}C$, Simultaneous recordings of temperature and electrical resistance of the skin of forehead were taken by means of Physiograph, using appropriate transducers. Temperature of various spots such as the cheek, upper tack and the forearm was also measured by the telethermometer at interval of two minutes. The results obtained were as follows: 1. Seventeen out of 20 subjects showed immediate rise in the skin temperature of the forehead, and 11 of them manifested the oscillating pattern of the skin temperature. The average of the largest peak amplitude was $0.58{\pm}0.355^{\circ}C$. 2. Even those who failed to show the immediate rise in the temperature did not keep the quiescence over 9 minutes, and delayed responses were revealed. 3. The rise in tile skin temperature is the favourable sign for the heat discipating mechanism only because the sweat glands are activated with the concomittant rise in the temperature of the skin. 4. There was a preceding or coincide fall in the electrical resistance of the skin, and it was also attributed to the glandular activity. 5. At rather cool room temperature, $20^{\circ}C$, no visible sweat was seen during the period of observation. Nevertheless it was obvious that latent activation of the sweat glands was triggered and the. threshold was lowered. This situation imitates the acclimatized condition in the hot environment, and it is likely to increase the tolerance in tropical climate from the view point of temperature regulation.

일산화탄소흡입(一酸化炭素吸入)이 비임신(非妊娠) 토끼자궁운동(子宮運動)에 미치는 영향(影響)

신동훈,김기곤,Shin, Dong-Hoon,Kim, Ki-Kon 대한생리학회 1975 대한생리학회지 Vol.9 No.2

Adult nonpregnant female rabbits were subjected to the study of the effects of carbon monoxide inhalation on the uterine motility. Animals were anesthetized with intravenous injection of nembutal, 35 mg/kg, and the uteri were exposed. Polyethylene tubing which had a small hole near the blind tip was inserted in the loop and normal saline was infused at a constant rate of 1.5 ml/min. On the other end of the loop, an outlet of fluid was made. When a peristaltic wave proceeded to the hole, a rise of the pressure was ensued and it was transmitted to the pressure transducer, making an upward deflection of the recording pen on the physiograph. Carbon monoxide, 1,000 ppm in the concentration, was inhaled through a tracheal cannula for 30 minutes, following fresh air for 30 minutes. In some cases, pure oxygen was also supplemented for another 30 minutes. Uterine motility was expressed in terms of the impulse that was the time integral of the pressure and of the frequency of the peristaltic waves. The results obtained were as follows. 1. When 1,000 ppm carbon monoxide was inhaled for 30 minutes, the impulse dropped to $72{\pm}16.5%$ and the frequency to $75{\pm}22.7%$ of the values obtained before the gas administration. 2. By fresh air for 30 minutes, the impulse and the frequency restored to $77{\pm}25.7%$ and $92{\pm}21.1%$, respectively. 3. By the supplement of pure oxygen for 30 minutes, no remarkable improvement were revealed, showing $89{\pm}35.2%$ in the impulse and $91{\pm}10.8%$ in the frequency, respectively. 4. There was an appreciable discrepancy in the recovery courses of the impulse and the frequency, suggesting different mechanisms attributable to the alteration by carbon monoxide inhalation.

154 kV XLPE 전력케이블의 부분방전 측정을 위한 FSA의 적용 및 표준화 연구

신동훈,양종석,황두현,임종천,박노준,박대희,Shin, Dong-Hoon,Lwin, Kyawsoe,Yang, Jong-Seok,Hwang, Doo-Hyun,Lim, Jong-Chun,Park, Noh-Joon,Park, Dae-Hee 한국전기전자재료학회 2007 전기전자재료학회논문지 Vol.20 No.5

The measuring system of the Partial discharge(PD) is very essential to investigate the hazard defects in the insulation systems of the high voltage engineering. We will discussed this research which has included two parts. The proposed method of Foil Sensor Array(FSA) and the normally used method in the practice. Firstly, it will be shown the improved sensitivity of a FSA sensor, which is our aim, compare with the existing normal foil sensor. And then, the linearity of detecting sensitivities of various kinds of FSA sensors was shown. According to our experiments, we can see that FSA sensor is more sensitivity than normal foil sensor and the linear increment property of FSA sensitivities.

일부 6가 크롬 폭로 작업자의 임파구 자매염색분체교환

신동훈,윤능기,서석권,예민해,Shin, Dong-Hoon,Yoon, Nung-Ki,Suh, Suk-Kwon,Yeh, Min-Hae 대한예방의학회 1990 예방의학회지 Vol.23 No.3

1989년 11월부터 4개월간 대구시내 소재 일부, 6가 크롬(삼산화크롬)으로 피막처리하는 도금작업장의 남성근로자를 대상으로 비중격천공이 있는 근로자 12명과 비중격천공이 없는 근로자 12명을 폭로군으로 하고 크롬에 폭로된 적이 없는 정상인 20명을 대조군으로 하여 개별면담을 통해 연령, 직업력, 흡연습관을 파악하였으며, 정맥혈을 채취하여 원자화 무염광로를 부착한 원자흡광도계로 혈중 크롬농도를 측정하였으며 말초혈액 중 임파구의 자매염색분체교환의 발현빈도를 조사하고 연령, 흡연습관, 직업력 및 혈중 크롬농도 등이 임파구 자매염색분체교환의 발현빈도에 미치는 영향을 조사했다. 크롬 도금작업의 말초혈액 중 임파구 자매염색분체교환의 발현빈도는 비중격 천공이 있는 군이 $10.1{\pm}1.6$, 비중격천공이 없는 군이 $8.5{\pm}3.4$이었고 대조군 $6.1{\pm}2.1$으로 세군간에 유의한 차이가 있었으며 (p<0.01), 비중격천공 군에서 가장 높은 빈도를 보였으며, 대조군에 비해 1.7배의 높은 빈도를 나타냈다. 혈중 크롬농도는 대조군이 $0.060{\pm}0.043{\mu}g/ml$, 크롬도금 작업자 중 비중격천공이 있는 군 $0.114{\pm}0.030{\mu}g/ml$, 비중격천공이 없는 군 $0.090{\pm}0.050{\mu}g/ml$로 세군간의 차이는 유의하였다 (p<0.01). 크롬도금 작업자와 대조군 모두 연령군별, 흡연습관별 및 근속년수에 따른 자매염색분체교환의 발현빈도에는 유의한 차이가 없었다. 혈중 크롬농도와 자매염색분체교환 발현빈도의 상관성은 상관계수, r=0.007로서 상관관계가 없었다 (Y=0.638 X+0.191, r=0.007. p>0.05). SCE 평균 발현빈도를 $y=(sum\;SCE)^{\frac{1}{2}}+(sum\;SCE+1)^{\frac{1}{2}}$를 이용하여 변형한 변수 y에 대해 연령, 흡연습관, 직업 및 혈중 크롬농도의 요인들로서 설명력은 32.3%였으며 가장 중요한 변수는 직업으로 나타났다. 이상의 결과로 보아 직업적인 크롬폭로에 의한 유전적 손상의 위험성이 어느 정토 있을 것으로 추측되며 생물학적 독성검정 지표로서 유용성이 있을 것으로 생각된다. To investigate the possibility of utilizing of sister chromatid exchange(SCE) analysis in lymphocytes as an indicator which could evaluate the effects of mutagenicity after in vivo exposure to hexavalent chromium, this study was conducted using some of chromium plating workers occupationally exposed to hexavalent chromium, chromium trioxide ($CrO_3$) in Taegu city. The study population was 12 Cr platers with perforation of nasal septum, 12 Cr platers without perforation of nasal septum and 20 controls. The SCE in peripheral blood lymphocytes of the subjects was analyzed and blood chromium concentration was estimated using the atomic absorption spectrophotometer (IL551) equipped with furnace atomizer (IL755). The mean SCE frequencies for Cr platers with and without perforation of nasal septum were statistically higher than those for control. The difference in SCE frequencies by age, smoking habits were not statistically significant both in Cr platers and controls. There was no difference in SCE frequencies by career of Cr platers workers. In Cr platers, the correlation between the mean SCE frequencies and chromium concentration in blood was not statistically significant. Using the transformation $y=(sum\;SCE)^{\frac{1}{2}}+(sum\;SCE+1)^{\frac{1}{2}}$, when the data was studied by multiple regression, it appeared that the influence of the occupation was the most important. Age, smoking, occupation and CrB(blood chromium concentration) together explain only 32.3% of interpersonal variation on SCE. The results in this study suggest tt a genetic risk due to occupationally exposure to hexavalent chromium is clearly inferable and thus, SCE analysis in human lymphocytes may be used indicator of biological toxic effects of chromium. Further, populatio analysis stuies are required before SCE frequency can be used as a mutagenic indicator in human population.

Estimating Sea Surface Temperature Change after Tide Embankment Construction using Landsat Data

신동훈,이규석,Shin, Dong-Hoon,Lee, Kyoo-Seock The Korean Association of Geographic Information S 2006 한국지리정보학회지 Vol.9 No.4

본 연구는 Landsat Thematic Mapper (TM) 영상의 열적외선 (Thermal Infrared: TIR) 밴드 자료를 이용하여 시화호와 그 주변지역의 해수면 온도 (SST: sea surface temperature)를 검출하고, 시화방조제 공사 후의 토지피복변화를 파악하기 위해 수행되었다. 해수면 온도의 측정은 해양체계 뿐만 아니라 해양과 대기 사이의 열적인 경계범위 연구에 있어 중요하다. 1970년대 이후, AVHRR (advanced very high resolution radiometer)과 Landsat TM (Thematic Mapper)과 같은 인공위성 영상의 원격탐사기법을 이용한 해수면 온도의 추출이 이루어졌다. 그러나 AVHRR 영상은 우리나라의 서해안 지역과 같은 매우 복잡한 해안선을 가지고 있는 지역에서는 조악한 공간 해상도로 인해 해수표면온도 추출에 한계가 있다. Landsat TM 위성영상은 본 연구지역과 같이 복잡하고 좁은 해안지역의 해수면 온도 추출에 유용하게 사용된다고 판단된다. This study investigates to detect Sea Surface Temperature (SST) and land cover change after tide embankment construction using Landsat Thematic Mapper (TM) Thermal Infrared (TIR) band data at Shihwa Lake and surrounding area. SST measurement is important for studies of both the structure of the ocean and as the thermal boundary between the ocean and the atmosphere. Since 1970s, the derivation of SST by satellite remote sensing (RS) has been applied to earth surface using Advanced Very High Resolution Radiometer (AVHRR) and Landsat TM. However, AVHRR has restriction in deriving SST in the area whose shoreline is complicated like western coast in South Korea because of coarse spatial resolution. The TIR band of TM images can be used to detect SST change whose shoreline is complicated and narrow like the study site. Thus, multi-temporal TM images were used for SST change detection in this study.

촉지 림프절의 세침흡인 세포검사 - 단일 기관의 1,346예 경험 -

신동훈,김지연,강현정,김익두,설미영,최경운,Shin, Dong-Hoon,Kim, Jee-Yeon,Kang, Hyun-Jeong,Kim, Ick-Doo,Sol, Mee-Young,Choi, Kyung-Un The Korean Society for Cytopathology 2007 대한세포병리학회지 Vol.18 No.2

The aim of this study was to evaluate the diagnostic value of fine needle aspiration cytology (FNAC) for the assessment of palpable enlarged lymph nodes. The authors reviewed the results of 1,346 FNACs of palpable enlarged lymph nodes performed at Pusan National University Hospital from 1998 to 2004. Of the 1,346 cases, 1,265 (94.0%) were satisfactory and 81 (6.0%) unsatisfactory. Cytologic diagnoses were judged in 488 cases, based on subsequent histologic diagnoses, clinical follow up, or both. Global results for all malignancies (lymphoid and non-lymphoid neoplasms) based on cases with final diagnoses, showed a sensitivity of 87.4% and a specificity of 98.7%. The overall diagnostic accuracy was 93,2%, and the false negative rate reduced from 12,6% to 7,3% when lymphomatous cases were excluded. The annual data for this period showed that the number of diagnostic lymph node biopsies and the rate of inadequately sampled material markedly decreased. Gene rearrangement studies for IgH and TCR ${\gamma}$ were helful in 30 cases. FNAC is a useful initial diagnostic procedure for the evaluation of palpable enlarged lymph nodes. However, the technique should be assisted by the appropriate ancillary studies and by proper interpretation by a cytopathologist.

도시하천경관복원 접근방법에 관한 고찰- 청계천 복원사업을 사례로 -

신동훈,이규석,Shin Dong-Hoon,Lee Kyoo-Seock 한국조경학회 2004 韓國造景學會誌 Vol.32 No.4

In the 1960s, polluted urban streams were covered and paved in concrete. Rivers became sewers buried under road. As a result, wildlife habitat was lost and the open stream space was gone. In the 1990s, there was a movement for restoring urban streams to enhance the quality of life of inhabitants. Chungkye Stream, whose covering began from early 1950s and ended in 1977, is now in the process of restoration together with the Central Business District (CBD) Redevelopment Plan. However, as the construction proceeds, several problems were raised, and serious controversies resulted. Therefore, this study aims to investigate the validity of the approach of the Chungkye Stream Restoration Project through a literature survey and a site survey, and to present the improved alternative. Ultimately, the study aims to contribute to present references or guidelines for similar urban stream restoration projects. The Chungkye Stream Restoration Project has some of the following problems. First, the construction should be done based on the long-term urban redevelopment plan. Second, the construction period should be extended to restore urban streams. Third, the cultural asset conservation plan should be implemented. In order to fulfill the anticipated purpose, the above mentioned problems need to be solved.