• 한국건축시공학회지
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• 제14권6호
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• pp.615-621
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• 2014

본 연구는 수치해석과 폭발 실증시험을 통해 조립식 PC 아치 탄약고의 설계 및 시공도면을 제시하였다. 제안된 탄약고의 방호성능은 미군의 UFC 3-340-02와 한국군의 국방 군사시설 설계기준(탄약고 설계지침)에서 제시된 최대 회전각도로 판별하였다. 아치형 탄약고의 기초설계를 위해 곡면형태인 반원형과 오발형에 대하여 폭발하중에 대한 방호성능을 수치해석을 통해 살펴본 결과 오발형이 타원형에 비하여 지점회전각이 적어 전반적으로 방호성능이 뛰어남을 확일 할 수 있었다. 이를 통해 아치형 조립식 PC 탄약고의 설계안 및 시공도를 제안하였으며, TNT 133.75kg을 구조체 벽체로부터 00m 이격하여 폭발시켜 실제 시공된 탄약고에 대한 방호성능을 검증하였다. 결론적으로, 본 연구에서 제안된 탄약고는 충분한 방호 여유력을 확보하고 있는 것으로 확인할 수 있었다. 향후 이러한 방호 여유력을 고려하여 재료의 절감을 통한 보다 경제적인 탄약고 설계도 가능할 것으로 사료된다.

• 생명과학회지
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• 제21권12호
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• pp.1698-1704
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• 2011

본 연구는 국화추출물이 산화적 스트레스에 의한 세포와 DNA의 손상에 미치는 영향을 조사하였다. 국화추출물의 DPPH 유리 라디칼과 수산화 라디칼의 제거 활성은 $200{\mu}g$/ml에서 각각 92.8%, 73.8%로 나타났으며, $Fe^{2+}$-chelating 효과는 59.4%로 나타났다. 국화 추출물의 지질과산화 억제능은 대조군의 90.3%의 활성을 보였으며, p21 단백질의 발현 수준은 대조군의 79.6%로 나타나 라디칼 처리군에 비해 높은 것으로 조사되었다. 또한 국화추출물의 DNA 분절화 억제 활성은 대조군의 89.6%를 보였고, DNA tail의 이동은 농도에 따른 차이는 있으나 대조군과 비교적 유사한 수준으로 감소되는 경향을 나타내었으며 phospho-H2AX 단백질의 발현은 라디칼 처리군의 79.8%에 해당하는 수준을 보여 DNA 인산화를 억제하는 데 높은 활성을 나타내었다. 따라서 본 연구의 국화추출물은 산화적 스트레스에 의한 생체 내 독성으로부터 세포와 DNA를 보호하는 데 효과적으로 작용하는 천연 항산화 물질로서의 응용이 기대된다.

• Journal of Microbiology and Biotechnology
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• 제13권3호
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• pp.444-450
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• 2003

In order to develop an effective means to treat P. aeruginosa infections, we have purified P. aeruginosa outer membrane proteins (OMPs)-specific human IgG antibody. In this study, we investigated the protective activity of the purified anti-OMPs IgC against P. aeruginosa infection in a rabbit endophthalmitis model. Rabbits were inoculated by an intravitreal injection with P. aeruginosa, and treated with a single dose of 1 mg anti-P. aeruginosa OMPs IgG. All the control rabbits predominantly developed edematous responses and opacity in the eyes, but the rabbits treated with the antibody showed only very limited degree of edema. Aliquots of the vitreous humor were extracted and analyzed for the number of viable bacteria and endotoxin level. The results showed that the anti-OMPs IgC significantly reduced the bacterial count compared with the control group, and that the endotoxin level of the vitreous from the IgG-treated rabbits was more than 70-fold lower 6 h after the administration than the control animals. These data suggested that the anti-P. aeruginosa OMPs IgG is effective in inhibiting the bacterial growth and thereby in reducing endotoxin levels in the vitreous, warranting further development of the anti-P. aeruginosa OMPs IgG as a therapeutic means for treating Pseudomonas endophthalmitis.

• Journal of Radiation Protection and Research
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• 제36권3호
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• pp.140-147
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• 2011

PET-CT 사용에 따른 피폭선량을 감소시키기 위한 행위적, 환경적 요인을 구체화하여 국내 실정에 맞는 방사선안전관리에 대한 가이드라인을 개발하고자 하였다. 연구방법론적 설계는 질적조사와 양적조사를 병행한 다단계-다방법론적 접근으로 선행연구 분석, 전문가 자문, 설문조사를 수행하였다. 분석대상은 대한핵의학회(2010년) 기준, 국내 설치된 109대 PET-CT 담당 방사선종사자의 응답지 139부이다. 연구도구는 설문지이고 크론바하 알파(Cronbach's ${\alpha}$)계수는 "방사선방어 환경구비 및 설치의 필요성" 0.818, "방사선방어 행위의 필요성" 0.916, "방사선방어 환경구비 및 설치수준" 0.722, "방사선방어 행위수준" 0.885로 모두 높게 나타났다. 환경 및 행위 중심의 방사선안전관리 가이드라인으로 도출된 점검항목은 방사선방어 환경점검으로 환자 5항목, 보호자 4항목, 방사선사 3항목, 공통적으로 적용되는 8항목으로 총 20항목이 구성되었고, 방사선방어 행위점검으로 환자 12항목, 보호자 1항목, 방사선사 7항목, 공통적으로 적용되는 6항목으로 총 26항목으로 구성되었다. 구체적인 점검목록은 <표 5-6>에 나타나 있다. 국내에서는 PET-CT사용에 따른 방사선피폭을 감소하기 위한 자체적인 안전관리 가이드라인이 부재한 상태이므로 본 연구에서 개발된 가이드라인은 국내 실정에 맞고 개입이 가능한 환경과 행위측면에 대해 각 피폭 대상별로 구체적인 점검내용으로 구성한 것에 의의가 있다고 본다.

• 한국산업보건학회지
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• 제33권1호
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• pp.12-18
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• 2023

Objectives: Personal protective equipment (PPE) is an essential means for protecting workers against hazardous agents or risks that threaten their safety and health. Governmental organizations related to safety and health in the workplace regulate the PPE rules to protect workers and to minimize damage from hazardous agents. This study discussed current PPE rules overseen by the Korea Ministry of Environment and explores future perspectives on the matter. Methods: This study was based on a review of PPE regulations with which every stakeholder should comply in the workplace. Both South Korean regulations enforced by the Ministry of Employment and Labor and the Ministry of Environment and cases from other countries were reviewed. Results: Regulations related to the PPE required for handling chemical substances in the workplace are enforced by the Occupational Safety and Health Act, Enforcement Decree, Enforcement Rules, and Notification of Protective Equipment Certification under the Ministry of Employment and Labor. The Ministry of Environment also regulates the PPE standards for 97 substances requiring preparation for accidents and adjustment of work conditions, but a recent amendment (partially amended on September 30, 2022) loosened some unreasonable or excessive provisions. It requires workers simply to carry or otherwise keep PPE handy instead of wearing it for some tasks in which hazardous chemicals are not handled directly. Conclusions: It is important to regularly review provisions that need to be improved or supplemented to help all stakeholders. Considerations should be also made to build a reasonable regulatory system that can induce more mature safety management in each workplace.

• 한국학교ㆍ지역보건교육학회지
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• 제14권2호
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• pp.47-57
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• 2013

Backgrounds: According to a high interest in health these days, a bicycle is being highlighted as a means of leisure activity and auxiliary transportation means. Along with an increase in this interest, there is tendency that even the width of bicycle utilization gets diverse and that bicycle accident is also rapidly growing. Purpose: The purpose of this study was to suggest a prevention measure available for reducing occurrence of bicycle accidents by analyzing the Epidemiological characteristics according to age and injury severity in bicycle-injured patients. Methods: This study analyzed 115 materials suitable for this study by examining a medical record of patients, who received the hospitalized treatment owing to bicycle accident from January 1, 2011 to December 31 at one general hospital in S city. Results: The male-and-female ratio of bicycle-injured patients stood at about 7:3. The average age was 38.14(${\pm}21.59$) years old. The largest injury happened in 40-59 years old(31.3%). The averagely hospitalized period was 17.33(${\pm}18.12$) days. Injury severity was the ratio of 2:8 in a mild case versus a serious case. As for drinking and smoking characteristics according to age, the injury occurred the most in between 40 and 59 years old for people with drinking and smoking and in under 19 years for people without drinking and smoking. According to injury severity, the ratio of serious case got higher in the higher age. This was indicated(${\chi}^2$=15.675, p=0.001) to be statistically significant. Conclusion: In this study, a bicycle accident was indicated to have high injury risk in young children, adolescents, and old-age group. Prevention measure and publicity are demanded for reducing injury occurrence such as the prevention education for bicycle accident and wearing protective gear focusing on the ages of corresponding to groups with risk of injury occurrence. In addition, the security of safe movement route is necessarily demanded in order to increase application level as an auxiliary transportation means.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1996년도 재료학회 추계학술발표회
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• pp.171-173
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• 1996

Ag coating on the textured YBCO was prepared by means of a Ag$_2$O brushed coating method. The contact between Ag coating and textured YBCO was examined by sharp knife cut and by the observation of SEM. The critical current densities of different textured YBCO samples, which included YBCO with and without Ag coating, and YBCO with Ag coating after hot moist text, were compared. The Ag coating does not influence the oxygen absorption of textured YBCO, but Ag coating can protect YBCO well from moisture and $CO_2$

• 한국염색가공학회지
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• 제7권2호
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• pp.55-62
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• 1995

Plasma polymerization of Perfiuoropropene(PFP) and n-Hexane was carried out in a tubular type reactor by means of 13.56MHz radio frequency generator at the fixed RF discharge power of 25W and at the pressures of 100mTorr, 140mTorr and 200mTorr. The thin films were deposited on PAN fabrics in order to improve the dimemsional stability of woven states in hot water laundry. IR spectroscopy was used for the analysis of the structures of the thin films deposited and SEM for examination of surfaces of the fabrics. the PAN fabrics, which were coated by thin films at several experimental conditions, were immersed in boiling water for 2 hours and then the dimension stability of woven states were evaluated. In spite of very thin films, the results of surface modification were satisfactory. In general the performace of thin films by PFP was superior to that of n-Hexane.

• 한국산업융합학회 논문집
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• 제4권3호
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• pp.263-266
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• 2001

In this paper, intelligent methods using digital protection relay in power SCADA system is developed in order to protect power systems by means of timely fault detection during operation and control at starting for induction motor which have various load environments and capacities in power systems. The digital protective relay was designed with DSP CPU(TMS320C31) to protect and measure more quickly and precisely. The test result on the basis of KEMC 1120 and IEC60255, show that the operation time error of the digital motor protection relay is improved within ${\pm}5%$. Also, we can control motors at starting according to starting types with simple method as programmable sequence editor. So we can improve the demerits of high cost and much manhour for rework.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.552-554
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• 2003

The second harmonic component is commonly used for blocking differential relay in power transformers. However, it is difficult to distinguish between inrush and internal winding fault with differential current protective relaying. This paper proposed a new method using Nuro-Fuzzy System based on HCM(Hard C-Means). The proposed system is more objective and systematic than existing model. The data used in input are 3-phase primary voltage and fundamental harmonic of differential current. Various states of transformer are simulated using BCTRAN and HYSDAT of EMTP. As a result of the application of algorithm in various cases, the exact discrimination between internal winding fault and inrush is performed.