Ni-Zn-Fe₂O₄의 조성비에 따른 전파흡수특성에 관한 연구

조재원,신용진,조치현,문현욱 明知大學校 産業技術硏究所 1993 産業技術硏究所論文集 Vol.12 No.-

This paper describes a study on absorption properties of electromagnetic wave for the composition ratio of Ni-Zn-Fe₂O₄ Ni-Zn-Fe₂O₄was composed of 48∼51mo1% Fe₂O₃,18~22mol% NiO and 27∼34mo1% ZnO. The sintering of the composition was carried out at 1200℃ for 2 hours. Through the experiments, it was found that the resonance phenomenon occured at low frequency range for high permeability and vice versa. In the case .of the composition of 49mo1% Fe₂O₃,20mo1% NiO and 31mo1% ZnO, the bandwidth ranged from 0. 37GHz to 0.95GHz with the absorption thickness of 10mm. Also, In the case of the composition 51mo1% Fe₂O₃, 22mo1% NiO and 27mo1% ZnO. the bandwidth ranged from 0.45GHz to 1.2GHz with the absorbtion thickness of 6mm. Therefore, it is proved that electromagnetic wave absorbers can be fabricated successfully within the bandwidth range mentioned above.

목초액의 엽면살포가 선학초(Agrimonia pilosa L.)의 종자수량에 미치는 영향

정대수,신상현,김현경,오주성,이용호 東亞大學校 大學院 2002 大學院論文集 Vol.27 No.-

Agrimonia pilosa L. has been used as a medicinal plant in traditional folk remedy, and it shows inereasing tendency at various sections such as medicine-making material, functional food, and agricultural chemicals using plant or extract. The treatment was 400times solution(50㎖), 600times solution(33.3㎖), 800times solution(25㎖), 1,000times solution(20㎖) and 1,200times solution(16.7㎖) level with foliar application of wood extraction in Agrimonia pilosa L. The results obtained through these experiments were summarized as follows; plant height, stem number, leaves was increased with 800times solution(25㎖) foliar application of wood extraction. Among foliar application of wood vinergar soution diluted by 800-1,200 times was most effective considering growth and yield as compared other dilutions and control plot.

인공모래 부산물 재활용 방안

김경남,신대용,이현종 강원대학교 부설 석재복합신소재 제품연구센터 2002 석재연 논문집 Vol.7 No.-

인공모래 제조시 부산물로 발생하는 석분슬러지에 의한 환경문제와 폐기되는 자원의 활용문제를 해결하기 위하여 석분슬러지와 점토 및 폐유리분말을 이용하여 900∼1,100℃로 소성하여 세라믹스 건자재를 제조하였다. 석분 슬러지는 평균입경 16.3㎛, 비표면적 0.42㎡/g, 화학조성은 CaO 46.43wt%, SiO_2, MgO 와 Al_2O_3가 7.83 wt% , 6.17 wt% 및 3.13 wt%이며, 주결정상은 calcite (CaCO_3)와 dolomite (CaMg(CO_3)_2)로서 약 800℃에서 CaCO_3나 CaMg(CO_3)_2의 열분해에 의한 32.52wt% 의 강열감량을 나타내었다. 석분슬러지와 점토를 이용한 시편(No. 1, 4, 7, 10 및 13)은 점토의 첨가량과 소성온도가 증가함에 따라 시편의 부피비중 및 압축강도는 증가하였으나 기공률과 흡수율은 감소하여 No. 1, 4, 및 7 시편은 부피비중 1.78∼1.98, 기공률 6.4∼12.5%, 흡수율 10.3∼12.7%, 압축강도 264∼370kgf/㎠을 나타내었다. 폐유리분말을 첨가한 시편(No. 2, 5, 6, 8, 9, 10 및 12)의 부피비중과 압축강도는 1.91∼2.63 및 213∼895kgf/㎠로서 폐유리분말의 첨가가 시편의 소결성과 압축강도의 향상에 기여하여 세라믹스 건자재로 사용이 가능하였다. The utilization of waste stone powder sludge produced secondarily from artificial sand plants of Ssangyoung resource development (Co.) and general waste, as was classified, became very important to solve the environmental problem and waste materials recycle. In the chemical composition of stone powder sludge, the amount of CaO was 46.43wt%, SiO_2, MgO and Al_2O_3 were 7.83 wt% 6.17 wt% and 3.13 wt%, respectively. The mean average particle size was 16.3㎛ and specific surface area was 0.42㎡/g. Main crystal phases were calcite (CaCO_3) and dolomite (CaMg(CO_3)_2) and ignition loss was 32.52wt% because of decomposition of CaCO_3 or CaMg(CO_3)_2. Specimens were fabricated by mixing the waste stone powder sludge, low-grade clay, waste glass powder and sintering at 900∼1,100℃ for 2 hours. The density and compressive strength of specimen increased with increasing the sintering temperature and the amount of clay. The specimen showed the bulk density of 1.78∼1.98, porosity of 6.4∼12.5%, water absorption 10.3∼12.7% and compressive strength of 264∼370 kgf/㎠. Those of the specimen heated at 1,050℃ increased with increasing the added amount of waste glass powder, bulk density was 1.91∼2.63 and compressive strength was 213∼895 kgf/㎠. Therefore, the waste stone powder sludge can be used as a constructional materials.

조선업 도장작업자의 유사노출군과 노출변이; 크실렌 노출을 중심으로

고상백,노영만,임현우,신용철,김수근,최홍열,김재용,장성훈 大韓産業醫學會 2001 대한직업환경의학회지 Vol.13 No.4

목적 : 조선업 도장 작업자의 크실렌 노출을 평가하기 위하여, 수행직무 및 밀폐특성에 따라 유사노출군으로 구분하여 노출 변이 및 동질성을 파악하고자 하였다. 방법 : 3회 이상 반복측정이 이루어진 근로자 중동일공정에서 직무상 변동이 없는 근로자 총 28명을 대상으로 하였다. 노출농도 값을 대수전환(lOgtransformation)하여 근로자간, 근로자내 노출 분산요소을 추정하기 위하여, nested randomeffects ANOVA model을 활용하였다. 선정된 유사노출군 내 구성원의 측정 평균이 동일하다고 할수 있는지를 검정하기 위하여 분산요인(9f)을 산출하였고, 쿨즈0.031일 경우 동일하다고 생각하였다.또한 노출 값을 대수전환하여 95 %의 근로자(b-R9s)가 2배수 범위 내에 측정값을 가질 경우 동일하다고 생각하였다. bwRSS의 값을 유사노출군내의 근로자들간(between worker)의 기하표준편차(bwsy)를 구한 후 exp(3.92 bwsy)로 계산하여 산출하였고, 그 값이 2이하이면 동일하다고 생각하였다. 결과 : 일반적으로 유사노출군은 노출농도가 비슷한 것이라는 생각과는 달리, 직무에 근거한 유사노출군은 동질성 검정상 이질적이었다. 분무도장과 붓도장 모두 bwRss은 2를 초과하였고, 룰 또한 0.031를 초과하여 변이 폭이 컸다. 그러나 밀폐특성에 따른 노출 분포의 변이성은 직무만으로 구분했을 때의 변이지표 보다 그 수치가 낮아 밀폐특성으로 직무의 변이성을 설명 할 수 있었다. 결론 : 직무에 근거한 유사노출군이 동질적이지알다는 결과는 유사노출군으로 구분된 근로자의 업무특성이 하나의 유사노출군으로 설정할 수 없다는 점을 시사한다. 따라서 향후 작업환경 측정 시 직무뿐만 아니라 특정 업무(specific task) 또는 세부작업현황까지 파악할 필요성을 제시하고 있다. Objectives : This study was conducted to assess the concentration of xylene exposure and exposure variability of a similar exposure group (SEG) in accordance with job title and confined space. Method : The study subjects included 28 workers working in the painting process in the ship-building industry. Measurement of subjects were repeated three times. Within and between-worker exposure valiance components were estimated from log-transformed exposure concentrations employing a one-way nested random effects analysis of variance model. A uniformly exposed group was defined as one where the between-worker variance(σB2) was less than or equal to 0.031 or bwR95 ≤2, where bwR95 =exp(3.92 bwSy) , representing the radio of the mean exposures of the 97.5th and 2.5th percentile groups of the workers sampled. Result : The results indicated that, contrary to popular belief, similar exposed groups based on job title were heterogeneous. The between-worker variance(σB2) is large(≥0.031) and the ratios of the 97.5th and 2.5th percentile workers of the log normally distributed exposures of each group of worriers was more than 2. However dividing job title into confined space (in-block, out-block, in/out-block) decreased the between-worker exposure variability. Conclusion : This study focused on the quantitative aspects of exposure in painters in the ship-building industry. We cannot accept the assumption that SEG are uniformly exposed, as a major component of variation in exposure relates to differences in tacks or other factors. Therefore, the observational schemes can be improved by investigating Job-specific task and practice.

21個 非對稱中心點群의 等價逆格子點

徐日煥,秋錦洪,李珍昊,朴晶蘭,郭相姬,金文執,李正秀,申容賢 충남대학교 자연과학연구소 1994 忠南科學硏究誌 Vol.21 No.2

32개 點群은 中心對稱(centrosymmetric)을 갖는 11가지 點群(Laue群)과 21個의 非對稱中心(noncentrosymmetric)點群으로 이루어졌다. 本 硏究에서는 21個 非對稱中心點群 各各의 等價回折面(等價逆格子點)들을 誘導하였다. The thirty two point groups consist of eleven Laue groups (centrosymmetric point groups) and twenty one noncentrosymmteric point groups. In this paper, the reciprocal lattice points equivalent under the operations of 21 noncentrosymmetric point groups are derived.

Minocycline Chloride 1회 주입에 의한 거대 간낭종 치험 1예

신용운,신승용,조현근,지동한,권계숙,문희용,김범수,김영수,김미영 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.32 No.2

Measurement of Outgassing in a Vacuum Environment

Shin, Yong Hyeon,Hong, Seung Soo,Lim, In Tae,Kim, J.H.,Seong, Dae Jin,Chung, Kwang Hwa,Moon, G.W.,Choi, Sung Woo Trans Tech Publications, Ltd. 2005 Key engineering materials Vol.277 No.-

<P>Outgassing, the evolution of gas from the material in a vacuum, is not only a source of micro contamination in a semiconductor or the flat display panel production process, but it also a limitation factor in the ultra clean process of nano-technology. The outgassing from the materials of satellites and spacecrafts must be controlled for increased safety and function because space is also a vacuum environment. Several methods are used in outgassing measurement in general, but there is no one method suitable for obtaining all outgassing data. The most suitable method for a particular application must be chosen by the experimenter or user. Three types of outgassing measurement systems were fabricated and characterized, ‘Throughput method,’ ‘Rate of Rise method’ and ‘Mass Loss Measurement method’. The outgassing rates of many kinds of materials were measured and characterized using these systems.</P>

Improvement of Airway inflammation by Platycodon grandiflorum during the repeated steaming process in BALB/c mice

Yong-Wook Shin(신용욱),Chul-Ho Lee(이철호),Shin-Woo Lee(이신우),Hyeon-Sik Jeon(전현식),Young-son Cho(조영손),Eun-Ju Jeong(정은주),Kwon-Rae Kim(김권래),Mi-Ae Ha(하미애),Jin-Woo Kim(김진우) 한국약용작물학회 2014 한국약용작물학회 학술대회논문집 Vol.2014 No.2

Status of research on vacuum technology in KRISS

Yong-Hyeon SHIN 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Effect of Bamboo salt-pro on carries-inducing properties of Streptococcus mutans

Shin, Hye-Young,You, Hyeon-Hee,Shin, Tae-Yong,Kim, Hyung-Min,You, Yong-Ouk Kyung Hee Oriental Medicine Research Center 2003 Oriental pharmacy and experimental medicine Vol.3 No.1

We studied the effect of Bamboo salt-pro on the growth and acid production of S. mutans. The growth of S.mutans was reduced by the presence of the Bamboo salt-pro (1 mg/ml) and NaCl (1 mg/ml) significantly, and the positive control group (1 % of NaF) also exhibited antibacterial activity significantly. Bamboo salt-pro (1 mg/ml) reduced the rate of acid production by S. mutans. Bamboo salt alone did not demonstrate such a reduction in acid production at the concentration of 1 mg/ml. The inhibitory action of Bamboo salt-pro on acid production was found at a concentration of 1 mg/ml, but bamboo salt alone was not at a concentration of 1 mg/ml. In addition, we investigated the anti-inflammatory effect of Bamboo salt-pro on human mast cell line HMC-1. Bamboo salt-pro (0.1 and 0.01 mg/ml) inhibited significantly the secretion of inflammatory cytokine, tumor necrosis factor-a with $59.47{\pm}0.15%$, $51.98{\pm}0.16%$ respectively. Our results suggest that Bamboo salt-pro importantly contributes to the prevention or treatment of periodontitis and other oral diseases and inflammatory diseases.