주택화재시 피난개시시간에 따른 피난안전해석

백열선 ; 최영상 김천대학교 2010 김천대학교 논문집 Vol.31 No.-

This study was performed to analysis evacuation safety in housing fire with different response time. The evacuation simulation has included the impact of smoke layer hight, heat and toxic gases by fire simulation program (CFAST). In this study, the effect of the response time has been investigated by using evacuation simulation program (building EXODUS). The evacuation simulation were conducted with five steps of response time for 4 occupants. As a results, the smoke layer hight was 1.7m from floor in the living room (compartment 3) 40 second after fire. For 150 seconds of response time and 170 second after fire, the first mortuary was occurred at the end of living room (compartment 3) near exit. Three mortuary were occurred 170 second after fire, they started from compartment 1 and 6 where are far from exit. From this study, earlier evacuation start is more important for safety in housing fire where is no fire alarm and automatic fire extinguishing system such as sprinkler.

화재규모에 따른 고시원의 화재안전해석

백열선 ; 최영상 김천대학교 2009 김천대학교 논문집 Vol.30 No.-

다중이용시설에서의 화재는 불특정다수가 이용하기 때문에 신속한 초기대응과 피난이 이루어지기 곤란하여 많은 재산과 인명피해가 발생하는 특징이 있다. 특히 여러번의 고시원 화재를 겪으면서 다중이용업소의 안전관리에 관한 특별법이 마련되어 시행되고 있으나 고시원시설은 신고의 의해 영업이 가능한 신종자유업종으로 분류되어 관리감독부서가 명확하지 않아 효율적인 안전관리가 어려운 현실이다. 대다수의 고시원은 통로가 좁고 불타기 쉬운 내장재를 사용함에 따라 화재연소속도가 빠르고 피난이 어려운 단점을 가지고 있다. 따라서 화재 종류와 규모에 따라 어떤 위험이 존재하는지에 대한 정확한 해석이 필요하다. 본 연구에서는 고시원방안에서 침대 메트릭스와 소파에 화재가 발생한 경우에 연기의 확산속도와 유독성 가스의 분포를 조사하여 어떤 위험이 발생하는지 CFAST 로 화재시물레이션을 수행하고 그 결과를 분석하였다. Since the public facilities are used by incidental many, it is difficult to react early and evacuate when fire breaks out. Due to these reasons, the fire causes many property damage and causalities in public facilities. Because there are many fire incidences in Gosiwon, the specialized law of safety that is specific for the public facilities has been made. However, Gosiwon is a new branch that is easily allowed to in business with a license or a permission from the government, and the execu-tive department is not clear that safety law is not really possible to enforce effi-ciently. Most of the Gosiwon's hallways are narrow, and they are made up of inflammable materials. The burning rate of the material is rapid, causing difficulty in evacuating. It is necessary to identify and analyze the risk and damage that can be caused by different types and sizes of fire. Therefore, in this study, we studied and analyzed the burning of mattress and furniture in Gosiwon rooms, the impact of smoke, heat and spreading of toxic gases with CFAST conflagration simulation.

급성 포름알데히드 가스 흡입에 의한 흰쥐 후각상피의 형태학적 변화

백선용,전재기,문용석,황승영,노환중,고의경,왕수건 대한해부학회 1998 Anatomy & Cell Biology Vol.31 No.3

생체분해성 망막압정을 이용한 망막고정에 대한 실험적 연구

김용백,민병무,김창식,박근성,김승영,길숙종,조항진,이성복,노승무,송규상,강대영,조준식,양준묵,정경수,최선웅,이진호,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

Biodegradable retinal fixation devices obtain mechnical fixation of the retina with desirable chorioretinal scarring and with the potential for local, sustained release of antimetabolites and steroids to inhibit proliferative vitreoretinopathy. We manufactured a biodegradable retinal tack with barb that was designed in order to prevent intrusion from implantation of retinal tacks. This study was carried to evaluate the efficacy for retinal fixation and the capability for sustained release of drugs with a newly designed biodegradable retinal tack Biodegradable retinal tacks were made of polymers of glycolic acids and were designed with barbs in a shape to prevent the disinsertion. Biodegradale retinal tacks are divided into 3 parts, a conical portion that is inserted into the sclera, a cylinder portion that remains in the vitreous, and a neck portion between the pin and the cylinder. The tapered conical end was manufactured to allow easy insertion through the retina and choroid into the sclera. A cylinder portion was manufactured with a tapered angle that fixes firmly into the orifice of 19 gauge spinal needle. A neck portion, 0.4 mm in diameter, was designed to prevent disinsertion from following implantation of retinal tack. The applicator was a 19 gauge spinal needle and its orifice was prepared to 15°angle to accept the tapered cylinder portion of the retinal tack. The retinal tacks, secured in the needles, were passed through the formed vitreous and inserted into the retina, choroid, and sclera and were released by pushing the internal needle, usually within 2-3mm of the medullary ray of the posterior rabbit retina A retinal tack was placed in each of 8 pigmented rabbit eyes. Slit-lamp biomicroscopy, indirect ophthalmoscopy and fundus photography were performed periodically from 1 day to 8 weeks after surgery. Eight eyes were enucleated and studied by light microscopy at 8 weeks. Biomicroscopic evaluation of the animals revealed edemas adjacent to the retinal surfaces immediately after insertion of the biodegradable retinal tacks in all the animals. These edemas disappeared after 1 week. The first noticeable change in the size of retinal tacks was shown after 2weeks. The size of the retinal tacks gradually got smaller, decreasing to about one-half at 4 weeks and about one-third at 8 weeks. All retinal tacks remained in inserted places without any movement for an 8 week period. On light microscopy, epiretinal proliferations were seen to extend into the vitreous cavity. Cellular capsules that lined the inner aspect of the scleral defect caused by tack insertion were found. However the adjacent retina had a normal cytologic appearance and architecture in all specimens. We manufactured a biodegradable retinal tack that is designed to prevent intrusion from implantation of retinal tacks. All biodegradable retinal tacks reduce in size with time, but no retinal tacks extruded from the inserted place. The newly designed biodegradable retinal tack can be used for retinal fixation and may be used as a vehicle for the introduction of pharmacologic agents to prevent the cellular events that promote proliferative vitreoretinopathy.

Layering시 복합레진 층간의 계면 결합에서 oxygen inhibition layer가 필수적인가?

김선영,조병훈,백승호,이인복 大韓齒科保存學會 2008 Restorative Dentistry & Endodontics Vol.33 No.4

본 연구의 목적은 여러 가지 계면조건의 변화를 통해서 layering 시 복합레진 층간의 결합에 oxygen inhibition layer (OIL)가 필수적인지를 고찰해보는 것이다. 가로 × 세로 × 두께가 16 × 28 × 2.5 ㎜인 알루미늄판에 지름 3.7 ㎜의 구멍을 형성하여 몰드를 제작하고 다음과 같이 복합레진 (Z-250, 3M ESPE)을 충전하여 광중합하였다. 1 군: 하층판에 복합레진을 충전하고 광중합 한 후, 상층판을 접합하고 레진을 충전하여 광중합을 하였다 (OIL를 남김). 2군: 하층판에 복합레진을 충전하고 팡중합 한 후 acetone에 적신 cotton으로 문질러서 OIL를 제거하고 상층판을 접합하여 복합레진을 충전하고 광중합을 하였다 (OIL를 제거). 3군: 하층판에 복합레진을 충전하고 Mylar strip을 접합하여 공기와의 접촉을 차단한 후 광중합을 하였다. Mylar strip을 제거하고 상층판을 접합 후 복합레진을 충전하여 광중합을 하였다 (OIL형성을 억제). 4군: 하층판에 복합레진을 충전하고 광중합 한 후 glycerin을 OIL표면에 도포하고 다시 광중합하였다. 상층판을 접합하여 복합레진을 충전하고 광중합을 하였다 (OIL를 중합). 5군 (대조군): 하층판과 상층판의 경계에 복합레진층의 계면이 위치하지 않도록 복합레진을 bulk충전하였다 (계면 형성 없이 bulk 충전한 복합레진). 24시간 100% 습도에서 보관 후 상층판과 하층판 사이의 계면 전단결합강도를 측정하고 파절 양상을 관찰하였다. 계면을 통한 중합과정의 확산을 관찰하기 위하여 제조한 광개시제가 들어있지 않은 실험적 복합레진 (Exp_Com)을 몰드에 충전하고 상부에 flowable 복합 레진 (Aelite Flow) 또는 접착레진 (ScotchBond Multipurpose)을 접촉시킨 후 광조사하였다. 몰드내의 미중합된 Exp_Com을 acetone bath 에서 5 분 동안 제거한 후 몰드내에 다시 Aelite Flow를 충전하고 광중합을 시행하였다. 경화된 복합레진 시편의 단면을 관찰하여 ExP_Com 층의 두께를 측정하였다. OIL를 배제하거나 중합시킨 2-4 군은 OIL이 존재하는 1 군과 통계적으로 유의한 결합강도의 차이를 보이지 않았으며, Mylar strip을 이용하여 OIL의 생성을 억제했던 3 군과 glycerin을 도포하여 OIL를 중합시킨 4 군은 계면을 생성하지 않은 대조군인 5 군과도 통계적으로 유의한 차이를 보이지 않았다. 중합과정의 확산에 의해 중합개시제가 포함되지 않은 Exp_Com내에 중합된 층이 생겨난 것을 시각적으로 확인할 수 있었으며, Exp_Com의 중합층 두께는 flowable 레진의 경우 20,95 (0.90) um였고 접착레진의 경우 42.13 (2.09) 였다. This study was aimed to investigate whether an oxygen inhibition layer (OIL) is essential for the interfacial bonding between resin composite layers or not. A composite (Z-250, 3M ESPE) was filled in two layers using two aluminum plate molds with a hole of 3.7 ㎜ diameter. The surface of first layer of cured composite was prepared by one of five methods as followings. thereafter second layer of composite was filled and cured: Group 1 - OIL is allowed to remain on the surface of cured composite; Group 2 - OIL was removed by rubbing with acetone-soaked cotton; Group 3 - formation of the OIL was inhibited using a Mylar strip; Group 4 - OIL was covered with glycerin and light-cured; Group 5 (control) - composite was bulk-filled in a layer. The interfacial shear bond strength between two layers was tested and the fracture modes were observed. To investigate the propagation of polymerization reaction from active area having a photo-initiator to inactive area without the initiator, a flowable composite (Aelite Flow) or an adhesive resin (Adhesive of ScotchBond Multipurpose) was placed over an experimental composite (Exp_Com) which does not include a photoinitiator and light-cured. After sectioning the specimen, the cured thickness of the Exp_Com was measured. The bond strength of group 2, 3 and 4 did not show statistically significant difference with group 1. Groups 3 and 4 were not statistically significant different with control group 5. The cured thicknesses of Exp_Com under the flowable resin and adhesive resin were 20.95 (0.90) um and 42.13 (2.09), respectively.

노인 인구에서 신경인지기능저하와 혈청 지질농도와의 상관성

유영선,최석주,정성수,김지은,윤성욱,전동욱,백준형,박성우,이정구,추일한,김영훈 大韓神經精神醫學會 2008 신경정신의학 Vol.47 No.6

Objectives : In this study, the authors evaluated the correlation between eurocognitive impairments and serum lipids levels among Korean elderly over the age of 65. Methods : A total of 609 elderly individuals participated in this study. Screening for cognitive impairments were carried out using the Mini-Mental Status Examination-Korean version (MMSE-KC). There were 197 subjects above 1.5SD Of MMSE- KC and they were evaluated using the Korean versions of the Consortium to Establish a Registry for Alzheimer's Disease (AD) (CERAD-KC) and Geriatric Depression Scale (GDS-K). Results : There was a correlation between old age/low levels of education and AD (p<0.05, P<0.01). There was an inverse correlation between the serum level of total cholesterol and the word list recognition test scores. The serum levels of LDL cholesterol were inversely correlated with the scores on the constructional praxis test, word list recall test and word list recognition test. Inverse correlations between the serum level of triglyceride and scores on the word list recall test and word list recognition test were also observed. Conclusion : There were inverse correlations between the serum levels of lipids and language/memory function in subjects with AD.

Inconel 718 상향 엔드밀링시 절삭력에 미치는 공구형상오차의 영향

이영문,양승한,장승일,백승기,김선일,이동식 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.5

In an end milling process, the undeformed chip section and cutting forces vary periodically with the phase change of the tool. However, the real undeformed chip section area deviates from the geometrically ideal one owing to the cutter runout and tool shape error. In the current study, a method of estimating the real undeformed chip section area which reflects the cutter runout and tool shape error is presented during up-end milling processes of Inconel 718. The specific cutting forces, K_r and K_t are defined as the radial and tangential cutting forces divided by the modified chip section area, respectively. Both of the K_r and K_t values become smaller as the helix angle increases from 30˚ to 40˚. Whereas they become larger as the helix angle increases from 40˚ to 50˚. The K_r and K_t values show a tendency to decrease with increase of the modified chip section area.

강원지역의 자원관리를 위한 지리정보시스템 개발

서백수,임길재,정영준,송화선,류창희,민경원,서희정 강원대학교 석재복합신소재제품연구센터 1997 석재연 논문집 Vol.2 No.-

강원도는 오랫동안 금속, 비금속, 석재 및 석탄과 같은 지하자원들을 공급하는 국내 주요생산지로 알려져 왔으나, 장기적인 채광과 비 계획적인 생산으로 인하여 매장량이 고갈되고 있으며, 대외적으로 생산 경쟁력 마저 잃어가고 있다. 이러한 문제점에 대한 해결방안의 일환으로 본 연구에서는 강원도내에 산재되어 있는 지하자원의 분포, 자원 생산시설 및 생산량, 경제성, 자원개발, 환경문제 등 자원관리에 필요한 제반사항을 수행할 수 있는 강원지역 자원 종합관리 GIS 시스템을 개발하였다. 이 시스템의 개발은 방대한 양의 정보 조사 및 저장, 오랜 개발기간, 많은 소요인력 및 개발 비용이 요구되기 때문에 본 연구에서는 조기에 자원관리 GIS 시스템을 개발하여 이와 관련된 생산 및 연구 분야에 조기에 적용할 수 있도록, 일차년도에는 현재 석재복합 신소재제품 연구센터의 집중적 연구대상 지역인 태백지역에 대한 탄광지역을 중심으로 자원 종합관리 GIS 시스템을 개발하였다. The Kangwon province has been well-known to be one of major underground resource producing districts which are mainly supplying metals, non-metals, stones, and coals. However, due to the long-term mining and unplanned production, the natural resource reserves have been rapidly drained and oversea production competition has been losing. In this study, we has developed a GIS system for regional resource management in the Kangwon province, which can operate, maintain, and manage the distribution of underground resources, resource production facilities, production and economic development, and environmental issues. The development of this system requires the collection, analysis, evaluation, and storage for a huge amount of research data, and in addition, the long period of time, the big research man power, and big development cost. Accordingly, to shorten the development period of time and to early apply itself to production, this stage of study has been intensively developed a regional resource GIS system for managing the mines scattered in the Tabak province, which is one of hottest RRC's research areas.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

아말감과 복합레진의 수복 과정과 수복 후 발생하는 상아세관액 흐름의 실시간 측정

김선영,조병훈,백승호,임범순,이인복 대한치과보존학회 2009 Restorative Dentistry & Endodontics Vol.34 No.6

본 연구의 목적은 아말감과 복합레진의 수복 과정과 수복 후 상아세관액의 흐름(dentinal fluid flow, DFF)을 측정하기 위함이다. 치근을 절제한 제 3 대구치를 자체 제작한 미세 유체 흐름 측정장치에 연결한 후 1급 와동을 형성하여 아말감과 복합레진 수복을 시행하였다. DFF의 측정은 와동 형성부터 수복 후 30분까지 연속적으로 이루어졌고, 수복 후 3, 7일에 재 측정하였다. 주수 하에 와동 형성 시 DFF는 inward로, 끝난 후에는 outward로 바뀌었다. 아말감 충전 시 DFF는 inward로 바뀌었고 충전 완료 후 미약한 outward DFF를 보였다. 복합레진 수복의 경우, 산 처리 후 수세와 건조 시 각각 inward와 outward DFF를 보였고 primer도포 후 공기 분사는 급격한 outward, 소수성 본딩제를 적용하는 단계에서는 outward 였던 DFF가 감소하여 0에 가까워지거나 약간 inward 흐름을 보였다. 접착제와 복합레진의 광중합은 급격한 inward의 DFF를 일으켰다. 수복 후 30분, 3일, 7일째 수복 재료에 따른 DFF의 감소에 통계적으로 유의한 차이는 없었다 (p>0.05). The aim of this study was to measure the dentinal tubular fluid flow (DFF) during and after amalgam and composite restorations. A newly designed fluid flow measurement instrument was made. A third molar cut at 3 mm apical from the CEJ was connected to the flow measuring device under a hydrostatic pressure of 15 . Class I cavity was prepared and restored with either amalgam (Copalite varnish and Bestaloy) or composite (Z-250 with ScotchBond MultiPurpose: MP, Single Bond 2: SB, Clearfil SE Bond: CE and Easy Bond: EB as bonding systems). The DFF was measured from the intact tooth state through restoration procedures to 30 minutes after restoration, and re-measured at 3 and 7days after restoration. Inward fluid flow (IF) during cavity preparation was followed by outward flow (OF) after preparation, In amalgam restoration, the OF changed to IF during amalgam filling and slight OF followed after finishing. In composite restoration, application CE and EB showed a continuous OF and air-dry increased rapidly the OF until light-curing, whereas in MP and SB, rinse and dry caused IF and OF, respectively. Application of hydrophobic bonding resin in MP and CE caused a decrease in flow rate or even slight IF. Light-curing of adhesive and composite showed an abrupt IF. There was no statistically significant difference in the reduction of DFF among the materials at 30 min. 3 and 7 days after restoration (p > 0.05).