지하철 진동이 주변지반 및 인접구조물에 미치는 영향

강호정 漢陽大學校 1986 국내석사

새의 조형성에 관한 연구 -장신구 제작을 중심으로-

강호정 창원대학교 2015 국내석사

인간의 삶은 탄생의 순간부터 많은 관계 속에서 살아간다. 가족, 친구, 동료, 사회적인 모임이나 단체에 소속되어 본인이 원하던 원하지 않던 사회의 일원으로 긴 삶을 살아간다. 이 사회적인 인간관계 속에서 우리는 즐거움, 슬픔, 분노, 기쁨과 같은 여러가지 감정의 소용돌이 속에서 인생이란 여정을 걷고 있다. 또한 자신들이 속한 사회, 가정, 단체 등에서 많은 책임과 의무에 이끌려 자아에 의해 때론 타인에 의해 주어진 환경의 틀에 갇혀서 길들여지고 그것을 당연한 숙명처럼 받아들이면서 삶을 살아가고 있다. 보람되고 행복도 느끼겠지만 누구나 한번 씩 책임과 의무라는 족쇄에서 벗어나 맘껏 자유를 꿈꾼다. 현대 사회를 살아가는 한 일원으로써 이와 같은 삶의 지루함이나 속박에서의 일탈을 꿈꾸고 자유에 대한 욕망을 갈구하고 희망이라는 날개 짓을 염원하기도 한다. 새는 하늘을 날 수 있는 동물로써 예로부터 인간에게 동경의 대상이 되어왔다. 그리고 생김새가 가녀리고 연약한 존재로 새의 이미지가 다채로운 모습으로 표현하기에 충분하고 인간의 욕망을 대신해 줄 수 있는 매개체로 복잡한 인간의 감정을 표현하기에 충분한 소재라고 판단된다. 본인이 연구하는 작품은 새의 모티브를 전제로 비상과 희망이라는 상징성을 벗어나서 비상을 꿈꾸는 인간의 생활모습 즉, 언제나 반복되는 일상, 가족에 일에 때론 국가에 대한 책임과 의무에 힘들어 하고 숙명처럼 살아가는 우리들의 일상생활을 표현하고자 한다. 또 그 속에서 작으나마 나의 존재를 표현하고 그곳이 부정적인 면만 있는 것이 아니고 작은 어울림 속에서의 조화도 있으며, 책임과 의무를 다하여 이루어낸 보람과 자부심도 있고, 인간관계에서의 사랑과 정이라는 따스함도 표현하였다. 작품에서의 중심은 인간이다. 인간을 새의 형상을 통하여 표현하여 인간의 삶을 비추어 재조명하는데 목적을 두고 있기 때문이다. 작품제작에 있어서 새의 형태를 사실적으로 묘사하기 보다는 새가 가진 유선형을 강조하여 간결하고 단순화시켜서 조형적 요소와 특징을 강조하여 금속의 차갑고 딱딱한 소재를 부드럽고 따스함을 전달하는데 목적을 두고 때론 어우러지게 때론 숨어 버리게 때론 튀어나오게 포근하게 감싸 안긴 듯 표현하여 새를 통해 삶의 형태를 고찰하고자 하였다. 이와 같은 연구는 앞으로의 작업 방향과 삶에 있어서 자아성찰과 자아실현을 위해 끊임없이 노력하고 고뇌하는 인간의 본성에 대한 연구를 바탕으로 자아를 완성하고 성숙되어 삶에 대한 올바른 인식과 태도를 본인을 포함한 많은 이들에게 인식되는 기회가 되기를 바란다.

알레르기성 비염환자의 부비동조직에서 IL1, 4, 5의 발현에 대한 면역조직화학적 연구

강호정 東亞大學校 大學院 2000 국내석사

배경 : 알레르기성 비염과 만성 부비동염이 동반된 경우를 임상에서 흔히 경험하게 되는데, IgE와 관련된 제 1형 과민성반응이 만성부비동염의 병인에 영향을 미치는 것으로 알려져 있으나 이의 실험적 증명은 충분히 이루어지지 않았다. 목적 : 알레르기성 비염이 동반된 만성 부비동염 환자의 부비동 점막내에서 IL1, 4 및 5의 발현유무 및 정도를 면역조직화학법을 이용하여, 비알레르기성 환자군과 비교함으로써 만성 부비동염의 병인에 미치는 알레르기성 반응의 역할을 규명하고자 하였다. 재료 및 방법 : 본원 이비인후과를 내원한 환자중 증상, 국소소견 및 방사선학적 소견상 만성 부비동염으로 진단되어 부비동 내시경수술을 시행받은 환자 10명을 대상으로 하였다. 이들 중 5명은 알레르기성 비염의 병력이 있고 MAST검사 및 알레르기 피부반응 검사에서 알레르기성 비염으로 진단받은 환자였고(실험군), 나머지 5명은 알레르기검사상 알레르기비염의 소견이 없는 만성 부비동염 환자였다(대조군). 두 군 모두에서 H&E 염색 및 cytokines(IL1, 4, 5)에 대한 면역조직화학검사를 시행하여, 침윤하고 있는 호산구세포의 수치 및 cytokines의 발현유무 및 정도를 관찰하였다. 결과 : 알레르기환자군에서 호산구수치는 120±60으로 비알레르기군의 5±1보다 높게 관찰되었다. IL1은 주로 혈관조직과 상피조직에서 양성으로 염색되고, 점막하 세포에서도 일부 염색되었는데, 두군에서 유의한 차이는 없었다. IL5는 주로 점막하세포와 상피조직에서 양성으로 염색되고, 알레르기군이 비알레르기군보다 높게 발현됨이 관찰되었다. IL4는 두 군 모두에서 염색이 되지 않았다. 결론 : 비록 대상자수가 적어 통계학적 의의는 적어나, 부비동 점막을 대상으로 한 본 연구에서도 알레르기성 부비동염의 병인에 있어서 제 1형 과민성 반응의 역할이 중요함을 확인할 수 있었다. We often encounter allergic rhinitis patients with an accompaning sinusitis. Typer Ⅰ allergies are believed to be involved in allergic sinusitis. However there is not enough evidence for this. We purposed to determine the role of IgE mediated allergic reactions in allergic sinusitis by investigating the immunohistochemical differences of IL1,4,5 between patients with allergic sinusitis and control subjects with non allergic chronic sinusitis. Ten chronic paranasal sinusitis patients confirmed by symptom, local finding and radiologic finding were included for this study. All patients underwent endoscopic sinus surgery and ethmoid sinus mucosa was taken for specimen. Among them, five allergic patients were selected by history of allergic rhinitis and confirmed by positive allergic reactions in MAST and skin tests. Specimens were stained and we measured the number of eosinophils and the concentration of cytokines(IL 1,4,5). The number of eosinophils was higher in paranasal sinus mucosa front patients with allergic sinusitis IL1 positive cells were expressed in epithelium and vessels, and partially submucosal cells. But There was no significant difference in concentration of Ⅲ between two groups. IL5 positive cells were expressed in vessels, submucosal cells, and the concentraion of IL5 was higher in the mucosa of allergic sinusitis. Expression of IL4 was not detected in both groups. 12. Yamaguchi Y, .Suda T, Sudal et al : Purified interleukin-5 supports the terminal differentiation and proliferation of murine eosinophilic precursors. J Exp Med 167:43-56 (1988) 13. Shirasaki H, Asakura K. Narlta s et al : A study of experimental allergic sinusitis on guinea pigs. Oto Rhinol Laryngol(Tokyo) 38:232-237 (1995).

비행성능 최적화를 위한 헬리콥터 로터 설계

姜鎬廷 建國大學校 大學院 2009 국내석사

회전익 항공기는 수직이착륙, 호버링 등 좁은 공간에서의 비행이 가능한 특성으로 인해 산악 지형에 적합한 항공기 형태이며, 민간용이나 군용으로서 활발하게 사용되고 있다. 회전익 항공기는 회전하는 로터에 의해 양력과 추력을 동시 얻는 특성으로 인하여, 고정익 항공기기에 비해 형상 및 성능을 결정하는 요소가 복잡하고 다양하다. 그렇기 때문에 공력, 구조, 로터 동역학 등의 복합적인 분야를 고려하여 해석하는 것이 필요하다. 본 연구에서는 회전익 항공기의 사이징 및 성능해석 프로그램을 개발하고, 트림 프로그램과 연계 해석이 가능하도록 프로그램을 통합하였으며, 통합된 프로그램을 이용하여, 회전익 항공기 로터 블레이드의 최적 형상 설계를 수행하였다. 형상 설계의 변수로는 블레이드의 형상 변수들과 에어포일의 형상을 선정하였으며, 블레이드 형상에 대한 해석은 성능해석 프로그램을 통하여 수행하고, 에어포일 형상에 대한 해석은 panel method 기반의 프로그램을 사용하여 진행하였다. 본 연구를 통하여 개발된 프로세스는 회전익 항공기 전체 형상에 관한 최적화 연구에 적용될 수 있을 것이다. Rotorcraft have a special characteristics about hovering, vertical takeoff and Landing. In this reason, It is suitable aircraft for using the mountainous area. Therefore rotorcraft is used in civil and military. Rotorcraft is obtained Lift and thrust by the rotor. for this reason, configuration and performance selection factors are more complicated then fixed wing aircraft. therefore, multidisciplinary design was required for rotorcraft design that considering the aerodynamics, structure and rotor dynamics. In this study, rotorcraft sizing and performance analysis program is developed. That program is integrated with trim analysis program. Using that integrated program, rotorcraft rotor blade optimum design is performed. blade configuration and airfoil shape are selected on design variables. Blade configuration is analyzed by performance analysis program, airfoil shape is calculated by panel method based program. Developed design process through this study, will be apply to rotorcraft optimum configuration design.

Avian myeloblast virus reverse transe transcriptase 활성 저해 세균의 분리

강호정 濟州大學校 大學院 2008 국내석사

To screen antiretroviral compounds from microbial metabolites, 300 soil microorganism strains focusing Actinomycete family were collected and purified in Jeju. Those microbial isolates were cultivated and their culture filtrates were used as the samples for screening antiretroviral compounds. Inhibitory activity of microbial culture filtrate against avian myeloblast virus(AMV) reverse transcriptase (RT) was determined. About 87% of the 300 isolates showed AMV RT inhibitory activity in the primary screening test. Those isolates that showed higher than 60% inhibition of RT activity were chosen and their inhibitory activities were confirmed repeatedly using their cell-free culture filtrate. The inhibition rates of BLK268, BLK115, BLK418 and BLK338 were 98.7± 0.3%, 97.9± 0.2%, 97.9± 2.7%, and 95.9± 1.6%, respectively. The isolates BLK311, BLK90, BLK462-2, BLK248-2, CB249-2, and BLK107 showed morer than 80% inhibition, and BLK4, BLK86, BLK123, and BLK39 higher than 70% inhibition of AMV RT activity. Among those isolates, six strains including BLK39, BLK90, BLK107, BLK115, BLK268 and BLK418 were chosen for further study. In order to confirm the dependence of the inhibitory activity on microbial metabolite concentration, the cell-free culture filtrates were diluted several folds and added to the RT activity assay system. The results demonstrated that RT inhibition rate increased in general as the dilution rate decreased. The heat stability of active microbial metabolites were also investigated. When the culture filtrates were preincubated for 1 hour at 30℃ or less, no decrease in the inhibitory activity was observed. But most of the isolates lost the inhibitory activity rapidly at temperatures higher than 50℃, whereas the isolate BLK90 maintained relatively high inhibitory activity at above 50℃. The unknown isolates were identified through 16S rRNA gene analysis. The nucleotide sequences of 16S rDNA from BLK39, BLK90, BLK107, BLK115, BLK268 and BLK418 were determined and compared with those of other known microbial species. The isolates BLK 39, BLK115, BLK268 and BLK418 showed more than 96% sequence homology with Streptomyces species. Meanwhile, the 16S rDNAs of isolate BLK90 and BLK107 were similar to those of gram negative bacteria which belong to the genus Erwinia or Pantoea. Morphological features of these bacteria were consistent with the results of rDNA sequence analysis. Further research about inhibition mechanism and chemical nature of those bacterial metabolites are suggested.

인체 피부표면의 지질양과 지질구성성분의 분석에 관한 연구

강호정 이화여자대학교 대학원 1996 국내석사

인체의 피부표면지질은 phospholipids, sphingolipids, choesterols, cholestrolesters, fatty acids, triglycerides, squalene과 wax ester로 구성되며 이들은 체액손실을 막고 경피흡수를 조절하는 외에도 각질 형성세포간의 결합과 탈락 및 표피분화와 성장조절에도 관여한다고 알려져 있다. 본 연구는 정상인과 여드름 환자를 대상으로 피부표면지질의 추출유기용매와 신체부위에 따른 변화를 알아보고 이러한 지질변화가 건조한 피부와 여드름 발생에 미치는 영향을 알아보기 위하여 전자미세저울로 지질의 양을 측정하고 그 구성성분은 high performance thin layer chromatography와 photodensitometer로 측정한 결과는 다음과 같다. 1.Hexane, hexane/methanol(2:3, 용적비) 및 95% ethanol 세가지 용매에 따른 지질추출량은 통계적으로 유의한 차이가 없었다. 다른 용매에 비해 hexane으로 추출시 cholesterol-3-sulfate 및 총 ceramides는 적었고 (p<0.05) triglycerides는 많았다.(p<0.05) 2.이마의 지질량은 다른 부위에 비해 유의하게 많이 추출되었다.(p<0.01) ceramides은 뺨에서 많이 추출되었고 (p<0.05) cholesterol은 다리에서 많았으며 다리나 뺨보다 복부에서 triglycerides는 많았다. Cholesterol esters와 wax esters는 다리에서 뺨과 이마부위보다 적었다(p<0.05). 3.건조한 피부에서의 지질 추출량은 유의한 차이를 보이지 않았다. 건조한 피부보다 매끄러운 피부에서 tryglycerides는 많았지만(p<0.05) 그외 다른 지질구성성분에는 유의한 차이가 없었다. 4.정상인과 여드름 환자에서 지질추출량 및 그 구성성분에 유의한 차이는 없었다. 이상의 결과로 자극성과 홍반발생이 컸던 hexane/methanol 을 사용했을 때 ceramides와 극성지질(polar lipid)인 cholesterol-3-sulfate가 많이 추출되어 ceramides와 극성지질(polar lipid)이 피부장벽기능에 중요한 역할을 할 것이라는 것을 간접적으로 시사하며 겨울철의 피지선 기능감소가 건조한 피부의 원인이 된다고 생각되었다. 여드름 환자는 1차적인 각질층 지질변화에는 영향을 받지않는 것으로 여겨지며, 피부 표면지질의 추출용매에 따른 결과의 해석과 신체부위별 피부표면지질 구성성분의 차이가 피부기초학 연구에 도움이 되리라 여겨진다. The composition and biosynthesis of lipids in human skin have long been of considerable interest. The human skin surface lipids are derived from two principle sources; the sebaceous glands and the epidermis. The composition of skin surface lipids includes phospholipid, sphingolipid, choesterol, cholestrolesters, fatty acids, triglycerides, squalene and wax esters. And it is known that skin surface lipids may play function roles as follows:control of epidermal growth and differentiation, determinination of cohesion and desquamation of corneocyte, formation of lamellar granules and functioning as permeability barrier. Therefore we sat out to find out the differences of skin surface lipids according to the solvents, different anatomic sites and the posible effect of these lipid alteration on xerosis and development of acne. The skin surface lipids was extracted by cup method and analyzed the lipid composition by high perforance thin layer chromatography. The result were as follows: 1.Total amount of lipids extracted with 3 solvents(hexane, hexane/methanol, ethanol) were not significantly different. Hexane/methanol was more powerful extract solvent of epidermal lipids(ceramides & cholesterol ?3-sulfate) than hexane. Hexane/methanol and ethanol was more irritant than hexane. 2.The amount of skin surface lipids on the forehead was higher than that of the other site. The composition of lipids was different according to the sites(total ceramides in cheek and truglycerides in andomen were higher than other sites. Sterol easter and wax esters in leg were lower than other sites) 3.Triglycerides in smooth legs indicates higher proportion than that in xerotic legs. 4.There were no significant differences in amount and composition of extracted lipids between acne patients and normal surbject. In conclusion, these results might ce helpfuul to elucidate the differences of extracted lipid composition depending on the solvents and anatomin sites. Total ceramides and polar lipids may play an important role in the maintenance of the normal barrier function. it is thought that decreased sebaceous function (triglycerides, cholestrol esters and wax esters) would be significantly associated with xerosis of legs. These results suggest that total ceramides primarily have not been implicated in the follicular retention keratinization of acne.

진공 및 산소치환 다이캐스팅에서 공정변수에 따른 주조품 기포 거동 연구

강호정 부산대학교 대학원 2024 국내박사

최근 경량화 극대화를 위해 Al을 적용한 자동차 차체부품의 일체화, 대형화 추세가 강화되고 있으며, 이러한 대면적 주조성형은 주로 대형 다이캐스팅 성형법에 기반하고 있다. 특히 대형 차체 부품의 성형성 향상과 성형 후 열처리를 통한 강도 향상을 위해 고압 다이캐스팅 공법(HPDC)의 단점인 기포결함을 제어해야 한다. 본 연구에서는 기존 다이캐스팅 공법의 단점인 기포결함을 제어하기 위해 CT분석을 통해 porosity의 유형을 판별하고자 하였으며, 이를 바탕으로 산소치환 다이캐스팅 공 법(ORDC) 및 진공 다이캐스팅 공법(VDC)을 적용하여 주조품 내부의 기포결함을 줄여 기계적 특성을 증가시키고자 하였다. 첫 번째 연구에서는 주조품 내부의 porosity를 CT분석의 sphericity을 통해 blow hole과 shrinkage를 분리할 수 있는 기준을 제안하였으며, 이를 바탕으로 기존 공정인 HPDC 공법 뿐만 아니라 3가지 공법(VDC, ORDC, V/ORDC) 공법을 적용하여 시제품을 제조하고, 이를 비교하여 기존 공법 대비 결함이 감소하는 것을 확인하였다. 특히, V/ORDC 공법이 가장 결함이 적었으며, 기계적 특성이 우수하였다. 두 번째 연구에서는 ORDC 공정에서 산소주입량과 게이트 형상에 따른 기포 거동을 연구하였다. 산소 주입량을 10~40 L/min으로 설정하여 시험을 진행하였으며, 산소 주 입량이 증가할수록 기포결함이 감소하였다. 특히, 30 L/min 에서 가장 기포결함이 적 었으며, 기계적 특성이 증가하였다. 하지만, 40 L/min 에서는 기포결함이 소량 증가하 였다. ORDC 공정에서 gate 형상에 따른 기포 결함과 기계적 특성의 비교 결과, ORDC 공정에서는 Comb gate가 Integrated gate보다 가스 함유량이 낮고 기계적 특성이 훨 씬 높았다. 반면, 기존 HPDC 공정에서는 Comb gate가 가스 함유량을 증가시키고 기 계적 특성을 감소시켰다. 세 번째 연구에서는 VDC 공정에서 진공 칠벤트의 벤트 갭의 크기와 사출 팁 및 슬 리브 간의 공차에 따른 기포 거동을 연구하였다. 벤트 갭의 두께가 1.50 mm까지 증가 하면 캐비티 진공도가 향상되고 기포 결함이 감소하여 기계적 특성이 향상되었다. 사 출 팁과 슬리브간의 공차가 증가하면 캐비티 진공도가 반비례하여 감소하고, 기포 결 함이 증가하여 기계적 특성이 감소하였다. 특히, 공차가 0.20 mm에서 0.25 mm로 증 가할 때 슬리브에 외부 공기가 급격히 유입되며, 공차가 0.30 mm일 때 T6 열처리된 시험편의 인장강도와 신율이 가장 낮았다. 본 연구를 통해 CT분석을 통해 porosity의 유형을 판별하였으며, 다양한 다이캐스팅 공법을 적용하여 기포 결함을 효과적으로 제어 할 수 있음을 확인하였다. 특히, VDC와 ORDC 공정의 주요 공정 변수(산소 주입량, gate 형상, 칠벤트 사양, 사출팁과 슬리브 간 공차)에 따라 주조품의 기포결함과 기계적 특성에 중요한 영향을 미친다는 것을 확 인하였다. 이러한 결과는 초대형 차체 부품의 성형성 향상 및 기계적 특성 개선에 기 여 할 수 있을 것으로 판단된다.

폐폴리우레탄폼의 자연발화특성에 관한 연구

강호정 부경대학교 산업대학원 2002 국내석사

이산화탄소 소화설비에서 누출로 인한 질식사고의 원인분석과 대책에 관한 연구

강호정 부경대학교 2021 국내박사

A Study on the Cause Analysis and Countermeasures to Asphyxiation Accidents Due to the Leakage from Carbon Dioxide Fire Extinguishing Equipment Ho-Jung Kang Dept. of Interdisciplinary Program of Fire Protection and Disaster Prevention Engineering, Graduate School, Pukyong National University Abstract 1) In this study, the quantity of carbon dioxide leaked from the detached selector valve and the pressure changes during the leakage process were analyzed using the ID transient analysis on the system line of carbon di-oxide fire extinguishing equipment, and through the simulation of carbon dioxide diffusion using the computational fluid dynamics, the diffusion pa-th, the oxygen-carbon dioxide concentration at the operator's position and the effect caused by the pressure generated at the time of leakage were analyzed. Based on these, the carbon dioxide leakage process were analy-zed, and the results are as follows. (1) Due to the pressure of carbon dioxide released into the gas collection pipe room, the upper part of the outer wall of the gas collection pipe room made of gypsum board was damaged, and thus, CO2 was leaked into the adjacent passage. Subsequently, the oxygen concentration at the operator's position was reduced to minimum 5.3%, resulting in the asphyxiation accident due to the lack of oxygen. (2) The cause of the carbon dioxide leakage from the carbon dioxide fire extinguishing equipment is as follows. The locking pin, a countermeasure to prevent CO2 leakage, was partially installed due to the replacement work of the old automatic fire detection system, but upon receiving a false signal, the starter solenoid valve of the electrical room on the other floor was activated, which led to the release of CO2. (3) The cause of the detachment of the selector valve is as follows. As the dimensions of the female and male threads did not match, the approximately two threads were not fastened. During this process, the O-ring was detached, which weakened the strength of the joint further, and thus, the bolted part could not withstand the pressure of CO2, resulting in the detachment of the selector valve. (4) The ID Transient analysis, upon the assumption that the maximum pressure was 3.6 MPa and the atmospheric pressure 600 kPa at the position of the detached selector valve at the time of the accident, showed that the amount of carbon dioxide leaked from the exit port of the valve and that released from 2 open valves were similar, with a mean error of 15%. (5) In order to analyze the diffusion process of leaked carbon dioxide, FLACS v10.7 program was used, and the analysis of the oxygen concentration showed that it was 10% or less at the position of the operator at 25 seconds from the leakage of carbon dioxide and reduced to the minimum of 5.3% at 50 seconds when the leakage was completed, which was the concentration low enough to suffocate the operator. 2) As the asphyxiation accidents due to carbon dioxide has been continuing such as the accident at ○○Electronics in 2018 where the fire extinguishing agent, carbon dioxide, was leaked due to the damage of the selector valve of the fire extinguishing equipment, resulting in 3 casualties, the industrial distribution of carbon dioxide fire extinguishing equipment scattered across business sites, and the status of storage installation, inspection and management were investigated, and the safety measures for carbon dioxide extinguishing equipment suggested as follows. (1) The number of business sites that have the carbon dioxide fire extinguishing equipment is 282, and the industrial distribution for 630 storages and 2,011 protected areas is as follows. In terms of the region, it was divided into 7 such as the Gyeongnam region, Gyeongbuk region, Seoul metropolitan region, Jeonnam region, Jeonbuk region, Chungnam region and Chungbuk region, and the Seoul metropolitan region has the most storages with 242, followed by the Gyeongnam region and the Chungcheong regions. In terms of the industrial sector, the manufacturing sector has the most storages with 441, followed by the service and other service sectors. Therefore, in terms of the region, intensive management needs to be centered on the Seoul metropolitan and the Gyeongnam regions while the manufacturing sector should be intensively managed in terms of industry. (2) The number of installation of fire extinguishing agent storage facilities increased 12.7 times from 23 locations before the 1980s to 293 locations in the 1990s. Since the 2000s, the use of carbon dioxide, which accounts for most of the greenhouse gas reduction targets, has been slightly declining due to restrictions in the use of carbon dioxide following the international treaties on global warming. In addition, domestic fire regulations should be improved in line with global standards, where environmental concerns and regulations are being strengthened, and at the same time, new fire extinguishing equipment systems and fire extinguishing agents need to be developed. (3) A number of accidents involving casualties occur in the carbon dioxide fire extinguishing equipment, which is gas-based fire extinguishing equipment. The toxicity of carbon dioxide itself is low, but it can reduce the oxygen concentration depending on the released carbon dioxide concentration, which leads to a high risk of an asphyxiation accident. Thus, the total number of protected areas responding to the leakage of carbon dioxide from the carbon dioxide fire extinguishing equipment is 2,011, and the average number of protected areas covered by one storage is 3. The number of the storages that cover 1 - 5 protected areas is 558 (89%), accounting for the most of storages, and the maximum number of protected areas covered by a single storage is 28. Therefore, a review to strengthen legal regulations is needed, which enforce the location where carbon dioxide fire extinguishing equipment is installed to be limited to the area where there are no people around, and the protected areas to be installed separately. (4) In accordance with the ‘High Pressure Gas Safety Control Act’, carbon dioxide storage containers are managed by setting an inspection period so that those who store high-pressure gas and incombustible gas undergo regular inspections every two years. Accordingly, carbon dioxide fire extinguishing equipment storages are also undergoing regular inspections. Business sites outsourcing the inspection account for 568 (90%) of the total while 53 manufacturing sites (8%) and 2 non-manufacturing sites are conducting self-inspection. Most of the carbon dioxide fire extinguishing equipment storages (582 locations, 92%) have been inspected in the past two years, and thus the inspection cycle is good. However, the possibility of casualties due to the fire extinguishing agent is high, and as the inspection of facilities and containers that considers safety matters related to human casualties is insufficient with the design of fire extinguishing agents mainly focused on suppression of fires in the protected area or protected object even in the fire control, the regulations on the safety management of facilities and the maintenance of installed facilities should be devised. (5) The location of most of fire extinguishing equipment storages is above the ground with 468 sites (74%). The safety device to minimize the human casualties includes ventilation equipment, and the number of the facilities with ventilation equipment is 461 (73%). Among them, 283 facilities have forced ventilation, which is less than half of the total, and due to the nature of the facilities, the ventilation equipment is installed at the upper position, which limits the release of carbon dioxide. Natural ventilation was found in 178 facilities, which turned out to be one of the ventilation methods not providing effective ventilation in the enclosed protected area, rather increasing the risk of accidents, and not having detailed regulations. The number of storage facilities without ventilation is 166 (27%). Specific standards for ventilation methods should be strictly set, and detailed regulations for installation of forced ventilation as well as natural ventilation be prepared. (6) The investigation of the status of safety management found 100 (16%) storage sites where workers are directly exposed to the carbon dioxide extinguishing agent at its release, 515 sites (82%) that have not obtained approval for high-pressure gas safety control, 351 sites (56%) without a gas concentration meter and 56 sites (9%) without a firewall, indicating that safety control was partially substandard. When a worker enters a place where there is a carbon dioxide fire extinguishing system or a protected area where gas is released, a gas concentration meter capable of measuring the carbon dioxide or oxygen concentration should be provided, and a respirator that can be used in case of emergency should be ready in a nearby place. When working, in order to prevent the asphyxiation due to carbon dioxide before, during and after work, the carbon dioxide or oxygen concentration should be measured within the protected area and its surroundings, and only then, after ventilation if necessary, a worker should enter the protected area. (7) In the selector valve installed in the fire extinguishing equipment storage, the screw (screw thread) type is the most common with 430 sites (68%) just as in the business site where the accident has occurred. Besides, the welding type is used in 109 sites (17%) and others in 91 sites (14%). The National Fire Safety Code (NFSC) 106 on carbon dioxide fire extinguishing equipment stipulates that a selector valve should be installed at every protected area or protected object, and each selector valve be marked with the protected area or protected object covered by it. However, as it lacks details such as the fastening method of the selector valve, the regulations such as the installation of safe devices and the method of fastening the selector valve should be established in order to reduce the human casualties caused by the leakage from the carbon dioxide fire extinguishing equipment. (8) Carbon dioxide fire extinguishing facilities are installed and maintained on the basis of the National Fire Safety Code 106. However, by focusing on the facilities needed to extinguish fire based on the protected area or object, it relatively lacks the regulations on the life safety. Therefore, in order to prevent human casualties, the following countermeasures are needed. First, before commencement of work, by reviewing the work site drawings and conducting on-site inspection with the person in charge of operating fire safety facilities, the types of fire extinguishing equipment, their arrangement plan, types and forms of fire detectors, the risk of operating the carbon dioxide fire extinguishing equipment, operation of alarm devices, location of emergency exits, and safety measures should be checked. Second, when working in a place where a carbon dioxide fire extinguishing system is installed, the automatic and manual changeover switch must be switched to the ‘manual’ side (with interlocking with the solenoid valve of the control panel stopped) to prevent malfunction, and a locking device is used to prevent unwanted operation in advance. Furthermore, all people in the building are notified of the date, time, location and details of work through in-house broadcasting and bulletin boards, and a supervisor or watcher is deployed at the site to provide safety and health training regarding the harmful effects and danger of carbon dioxide. Third, how to evacuate before carbon dioxide is released within 30 seconds after the alarm system and the detector of carbon dioxide fire extinguishing equipment are activated should be learned in advance along with the evacuation route and assembly points. In addition, before entering the place where carbon dioxide is released, it should be ventilated completely, and if it is necessary to enter the place under the effect of carbon dioxide for the rescue of lives, a respirator must be worn.

피부 각질층의 보습기능에 관한 연구

강호정 이화여자대학교 대학원 1993 국내석사