콩 단백질/펙틴/몬모릴로나이트 나노복합 필름의 특성 및 산소 투과도 연구

정세환,김성철,조규순,신용섭,장상희,홍기헌,이태진,신부영 嶺南大學校 工業技術硏究所 2004 工業技術硏究所論文集 Vol.32 No.2

In this study, Mechanical property, thermal property, watervapor, and oxygen permeability of biodegradable Soy protein/Pectin-montmorillonite nanocomposite, prepared with Na^(+)-MMT, have been studied. X-ray diffraction and TEM experiments an polymer/silicate composite samples demonstrated that the intercalation of polymer chains leads to increase in the spacing between silicate layers. In addition, it were found that the intercalated Soy protein/Pectin/montmorillonite nanocomposite were prepared. It was found that the addition of only a small of clay was enough to improve the thermal stability and mechanical property of Soy protein/Pectin/montmorillonite nanocomposite. watervapor of Soy protein/Pectin/montmorillonite nanocomposite was generally lower than that of Soy protein/Pectin. oxygen permeability of Soy protein/Pectin/montmorillonite nanocomposite was generally lower than that of Soy protein/Pectin.

건설현장 근로자들의 안저예방실태와 사고예방과의 개선요인 조사연구

심규범,남철현,최상복,이송권,이정희,이순자,문기내,김문환 慶山大學校 保健福祉硏究所 2003 保健福祉硏究 Vol.8 No.-

This study was conducted to examine aspects of health and safety education and demand level of safety education in construction job sites in order to provide direction of safety education development. The subjects of this study were 566 workers who were working in construction job sites located in Daegu City and Kyungbuk Province. Data were collected from June 1, 2002 to August 30, 2002. The results of this study can be summarized as follows. 1. According to safety education by experience methods, the proportion of education by lecture was highest (90.6%). The proportion of education by field practice was 13.1%. 2. Among the education methods which they thought as the most desirable method, the proportion of audio-visual education was 39.4% and the proportion of education by experience was 37.5%. Those who had more monthly income and higher education level preferred audio-visual education, while those who were younger and less educated preferred education by experience. 3. In the case of the contents of the safety education which they thought as the most important one, the proportion of enhancement of safety awareness and education of risk factors was highest (24.7%). The groups of older workers, having longer working period, and belonging to higher education level preferred these contents. 4. According to the factors which were most important to increase effectiveness of the safety education were workers' voluntary participation (27.7%), 40 to 49 years old (27.7%), and monthly income of one million, five hundred thousand won to one million, nine hundred ninety thousand won (32.0%). The proportions of lower educated workers and working as daily workers were also high. 5. The variable which most influenced the safety education was age. The safety awareness of construction job sites was the second highest influential variable. From above results, it is clear that the workers' participation in the safety education was low since most of the safety educations were formal education by lecture. Although they participated in the education, the education was also not effective because they compulsorily participated in it. Therefore, it can be concluded that effective alternative policies must be formulated.

개량된 초임계수 산화법에 의한 염소계 유기물 (PCB, 4-DCBz)의 완전분해반응

이상환,박기철,박윤열,양종규,김정성,富安博 한국환경과학회 2005 한국환경과학회지 Vol.14 No.5

For the destruction of toxic chlorinated organic compounds, this study proposes improved supercritical water oxidation method (multistep oxidation) using sodium nitrate as an oxidizer. This method solves the problems involved in the existing supercritical water oxidation method. Multistep oxidation means that NaNO₃ is oxidized to N₂ via NaNO₂ and NO. Toxic and hard to destroy organic substances like para-dichlorobenzen(4-DCBz), polychlorinate biphenyl(PCB) ware oxidized to non toxic substances in a condition, in which rapid pressure and temperature rise is restrained as much as possible. 4-dichlorobenzene(4-DCBz) and Polychlorinate biphenyl(PCB) in condition(450℃, p_(w)=0.25g/cm³, 30min) Was discomposed perfectly.

산소의 첨가가 박막 백금측온저항체의 온도저항계수에 미치는 영향

설철규,김영진,장경훈,이건환,이정희 경북대학교 센서기술연구소 1997 센서技術學術大會論文集 Vol.8 No.1

A thin film Pt-RTD(resistance temperature device) was fabricated by using DC magnetron sputtering and laser patterning. A study was fulfilled to adjust the TCR(temperature coefficient of resistance) to 3850 ppm/℃ which is IEC751 standard and the influence of oxygen addition(0 ~ 20 %) on TCR was measured. The resistance of Pt-RTD was set to 1000 Q at 0 ℃ using laser patterning and trimming. The analyses of XRD and AES were used to characterise the platinum thin film. The TCR of Pt-RTD was measured by a high precision oil bath. When the addition of oxygen flow rate was 1 %, TCR was 3850 ppm/℃.

Cone beam형 전산화 단층영상을 이용한 하악전치부 영양관의 연구

강정호,김규태,최용석,황의환 대한구강악안면방사선학회 2006 Imaging Science in Dentistry Vol.36 No.3

Purpose : To evaluate location, distribution, diameter, and length of the nutrient canals on mandibular anterior region using a cone beam computed tomography (CBCT). Materials and Methods : Mandibular CBCT was performed on 33 adults (18 males and 15 females) with no history of systemic disease, and any other dental surgery history. Location, distribution, diameter, and length of the nutrient canals on mandibular anterior region were radiographically evaluated. A statistical comparison was done by SPSS. Results : In the location and distribution of nutrient canals, they were found in 6.8% at labial portion above root apex, in 93.28% at lingual portion above root apex in 46.2% at labial portion below root apex, and in 53.6% at lingual portion below root apex. Nutrient canals at lingual portion above root apex were most frequently observed between central and lateral incisors, and those at labial and lingual portion below root apex were most frequently observed between central incisors. The mean diameters of nutrient canals were 0.54 mm at labial portion above root apex, 0.61 mm at lingual portion above root apex, 0.66 mm at labial portion below root apex, and 0.76 mm at lingual portion below root apex. The mean lengths of nutrient canals were 2.63 mm at labial portion above root apex, 3.74 mm at lingual portion above root apex, 4.51 mm at labial portion below root apex, and 6.77 mm at lingual portion below root apex. Conclusion : CBCT is useful device to evaluate the anatomical structure of nutrient canals on mandibular anterior region.

Simvastatin이 골결손부 회복에 미치는 영향

강정호,김규태,최용석,이현우,황의환 대한구강악안면방사선학회 2008 Imaging Science in Dentistry Vol.38 No.3

Purpose : To observe and evaluate the effects of Simvastatin-induced osteogenesis on the wound healing of defective bone. Materials and Methods : 64 defective bones were created in the parietal bone of 32 New Zealand White rabbits. The defects were grafted with collagen matrix carriers mixed with Simvastatin solution in the experimental group of 16 rabbits and with collagen matrix carriers mixed with water in the controlled group. The rabbits were terminated at an interval of 3, 5, 7, and 9 days, 2, 4, 6, and 8 weeks after the formation of defective bone. The wound healing was evaluated by soft X-ray radiography. The tissues within defective bones were evaluated through the analysis of flow cytometry for the manifestation of Runx2 and Osteocalcin, and observed histopathologically by using H-E stain and Masson’s trichrome stain. Results : 1. In the experimental group, flow cytometry revealed more manifestation of Runx2 at 5, 7, and 9 days and Osteocalcin at 2 weeks than in the controlled groups, but there was few difference in comparison with the controlled group. 2. In the experimental group, flow cytometry revealed considerably more cells and erythrocytes at 5, 7, and 9 days in comparison with the controlled group. 3. In the experimental group, soft x-ray radiography revealed the extended formation of trabeculation at 2, 4, 6, and 8 weeks. 4. Histopathological features of the experimental group showed more fibroblasts and newly formed vessels at 5 and 7 days, and the formation of osteoid tissues at 9 days, and the newly formed trabeculations at 4 and 6 weeks. Conclusion : As the induced osteogenesis by Simvastatin, there was few contrast of the manifestation between Runx2 and Osteocalcin based on the differentiation of osteoblasts. But it was considered that the more formation of cells and erythrocytes depending on newly formed vessels in the experimental group obviously had an effect on the bone regeneration.

전류제어형 PWM 컨버터를 이용한 On-Line 무정전 전원장치에 관한 연구

김홍성,소정환,김한성,최규하 건국대학교 산업기술연구원 1995 건국기술연구논문지 Vol.20 No.-

Recently, according to the increasing critical loads such as commutation system, life support system in hospital, Computer, the supplying of stable power becomes more and more important. However line fault such as power failure, the variation of voltage or frequency frequently occurs since Utility supplies power to many kinds of loads through the same transmission line. Therefore it is indespensable to stabilize power source like UPS(Uninterruptible Power Supply). UPS system is divided into of-line type and on-line system is studied which can improve various drawbacks of off-line system. And the application of PWM converter to on-line UPS system is proposed and the PWM converter of input characteristics is investigated. As current control method, triangular method is adopted and PI controller is used for DC voltage regulation. And RMS control method is used for PWM inverter. This system is verified by digital simulation using ACSL package.

SS41 용접재의 피로크랙 진전거동에 관한 연구

최병기,권택용,정환규 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.1

SS41 is welded automatically and is investigated some effects of the welding residual stress in the growth and propagation of fatigue crack, so as to study the fatigue behaviour in the welding residual stress field. The summarized results are as follows; 1) In case of the load range is constant, as the stress ratio is changing to 0.1, 0.33 and 0.5 the propagation life is constant but the growth life decreases. And than, when maximum load or minimum load is constant, as the stress ratio increases the growth life and propagation life. 2) It was shown that the fatigue crack propagation ratio da/dN was almost constant regardless of the stress ratio change at constant load amplitude and that the larger stress ratio, the slower was the fatigue crack propagation ratio. 3) The opening ratio U is influenced by Kmax but it isn't only the function of Kmax because data range is very large. 4) The growing and propagation fatigue crack in the welding residual stress field is similar to original specimen after passing the original residual stress field.

정신분열병과 Neurotensin 수용체 유전자 다형성의 연합 연구

이유상,김형배,한진희,채영규,이정식,이혜순,주연호,김형섭,최인근,양병환 大韓神經精神醫學會 1999 신경정신의학 Vol.38 No.6

연구목적: Neurotensin(NT)은 NT수용체와 결합하여 그 효과를 나타내는 neuromodulator 혹은 neurotransmitter로서 대뇌에서 도파민의 분비를 조절하는데 중요한 역할을 한다. 근래의 연구에 의하면 NT와 그 수용체는 대뇌에서 항정신병 약물의 효과를 매개하는 것으로 생각되고 있으며 약물치료를 받지 않은 정신분열병 환자의 뇌척수액에서 NT의 양이 적으로 보고되고 있어 이들은 정신분열병과 깊은 관련을 가지고 있을 것으로 추정된다. 최근 NT수용체의 유전자의 3`인접영역에서 정보가치가 높은 4 염기반복 다형성이 발견되어 이를 유전 표지자로 하여 정신분열병과의 연합을 알아보았다. 방 법: 서로 혈연관계에 있지 않은 정신분열병 환자 120명(남자 91명, 여자 29명)과 정상 대조군 106명(남자 84명, 여자 22명)을 대상으로 하였다. PANSS를 사용하여 양성 및 음성을 알아보았다. 말초혈액에서 DNA를 분리한 후에 중합효소연쇄반응을 사용하여 3`인접영역에 있는 4 염기 반복 다형성을 증폭하였고 silver staining한 후에 유전자형을 관찰하였다. chi-square 검증과 Bonferroni`s correction을 사용하여 환자군과 정상 대조군간의 대립유전자 빈도의 차이를 알아보았다. 또한 양성 및 음성 환자군으로 나누어 차이를 알아보았다. 결 과: 총 23개의 대립유전자가 관찰되었으며, 399bp의 대립유전자(A10)의 빈도가 환자군보다 정상대조군에서 통계적으로 유의하게 높았다(χ²=16.49, df=1, p<0.001). 음성 정신분열병 환자군과 정상대조군 사이의 비교에서는 정상대조군의 A10의 빈도가 환자군보다 유의하게 높았다(χ²=21.33, df=1, p<0.001). 성별 비교에서 남자 정신분열병 환자군은 대조군에 비하여 A10의 분포가 유의하게 적었다. (χ²=13.71, df=1, p<0.001) 결 론: NT 수용체 유전자와 정신분열병사이에 음성연합이 관찰되었다. NT 수용체 유전자가 일부 정신분열병의 발병과정에서 확실하지는 않지만 어떤 종류의 보호기능을 할 수도 있다는 것을 암시한다. Objectives: Neurotensin(NT), of which functions are evoked by its interaction with neurotensin receptors(NTR), coexists with mesolimbic dopamine and regulates endogenous dopamine release. Recent studies have shown that NT with NTR exerts neuroleptic-like activity within the central nervous system and may play an important role in the pathogenesis and in the treatment of schizophrenia. We have examined the gentic association between schizophrenia and tetranucleotide repeat polymorphism in the 3-flanking region of the NTR gene to investigate the possible contribution of the NTR gene to the schizophrenia susceptibility. Methods: Among 23 alleles identified, the subjects were 120 patients(male 91, female 29)with schizophrenia and 106 normal healthy controls(male 84, female 22). They were unrelated native Korean. PANSS was used to determine positive or negative subgroup in the schizophrenic patients. Using polymerase chain reaction and polyacrylamide gel electrophoresis, tetranucleotide repeat polymorphism(CCTT and CTT) in the 3`-flanking region of NTR gene was observed. For a comparison of NTR gene`s allelic frequencies between patients with schizophrenia and normal healthy controls, chi-square test and Bonferroni`s correction was performed. Results: The frequency of A10 allele(base pair size=399)was significantly higher in normal healthy controls than schizophrenia(χ²=16.4902, df=1, p<.000). In the comparison between schizophrenic patients with negative symptoms and normal controls, the frequency of A10 allele was significantly higher in normal healthy control subjects than patients with schizophrenia(χ²=21.33, df=1, p<0.001). In the case of male, the frequency of A10 allele of schizophrenia was significantly higher than normal controls(χ²=13.71, df=1, p<0.001). Conclusions: NTR gene was negatively associated with schizophrenia. NTR gene`s tetranucleotide repeat polymorphism may provide some protective function against schizophrenia.

금식시 흰쥐 소장 점막 유당분해효소에 대한 갑상선 호르몬의 영향 및 이의 유전적 조절 기전

이국래,이동호,이한주,윤정환,김재규,정운태,정현채,송인성,김정룡 大韓消化器病學會 1996 大韓消化器病學會誌 Vol.28 No.6