• 제목/요약/키워드: Safe position

검색결과 319건 처리시간 0.028초

우주상황인식을 위한 인공우주물체 추락 예측 소프트웨어 개발 (Development of a Software for Re-Entry Prediction of Space Objects for Space Situational Awareness)

  • 최은정
    • 우주기술과 응용
    • /
    • 제1권1호
    • /
    • pp.23-32
    • /
    • 2021
  • 1톤 이상의 인공우주물체 중 통제가 불가능한 인공우주물체의 추락은 지상에서의 인명 및 자산 피해가 발생할 가능성이 높기 때문에 국가적으로도 '인공우주물체 추락·충돌 대응 매뉴얼'에 따라 우주물체 추락 상황에 대한 위기를 관리한다. 따라서 인공우주물체 추락 상황 및 위험도를 판단하기 위한 신속하고 정확한 인공우주물체 추락 예측 정보를 제공하는 것이 매우 중요하다. 인공우주물체 추락 예측 방법은 국내외 여러 기관들에서 수행하고 있으나, 국가적으로 신뢰할 수 있는 국내 독자적인 툴의 확보는 국가 우주위험 재난 위기 상황에서 매우 필수적이다. 본 연구에서는 인공우주물체의 추락 상황에서 관측으로부터 생성된 우주물체의 접촉궤도요소 또는 해외에서 공개되는 평균궤도요소를 활용하여 인공우주물체의 추락 예상 시각 및 지점을 정밀하게 예측할 수 있는 소프트웨어를 개발하였다. 개발된 소프트웨어는 그레이스 1호(Grace-1) 위성과 그레이스 2호(Grace-2), 톈궁 1호(Tiangong 1) 위성과 창정 5B호 로켓 잔해(CZ-5B)와 같은 실제 통제 불가능한 인공우주물체의 추락 상황에서 독자적인 우주물체 추락 예측 정보를 제공하여 검증하였다.

급·배기구 면적 변화가 누출 수소 환기에 미치는 영향에 관한 수치해석적 연구 (Numerical Study on the Effect of Area Changes in Air Inlets and Vent Ports on the Ventilation of Leaking Hydrogen)

  • 이창용;조대환
    • 해양환경안전학회지
    • /
    • 제28권2호
    • /
    • pp.385-393
    • /
    • 2022
  • 수소는 지구 온난화의 주범인 온실가스(GHG) 배출을 감소시키고 선박용 친환경 연료로서 대두되고 있다. 수소는 가연 하한계(Lower Flammability Limit, LFL)가 4 ~ 75 %이고 폭발 위험성이 큰 물질이다. 그래서 선박용으로 사용되려면 누출에 대비한 안전성이 충분히 확보되어야 한다. 본 연구에서는 수소탱크 저장실에서 수소 누출이 발생한 경우, 급·배기구의 면적 변화가 환기 성능에 미치는 영향을 분석하였다. 급·배기구의 면적은 1A = 740 mm × 740 mm이며 저장실 표면에 크기 및 위치 변경이 쉽도록 설정하였다. CFD 상용 소프트웨어인 ANSYS CFX ver 18.1을 이용하여 급·배기구의 면적을 1A, 2A, 3A, 5A로 변경하였고, 면적 변화에 따른 저장실 내의 수소 몰분율을 분석하였다. 그 결과 급기구 면적이 배기구 면적 증가에 비해 누출 수소의 농도를 더 감소시켰으며 단일 급기구보다 최소 2A 이상에서 환기 성능이 향상되었다. 급기구의 면적이 증가할수록 수소 층화가 저장실 상부부터 균일하게 형성되었지만 LFL 범위는 벗어나 있었다. 그러나 배기구는 면적을 단순히 증가하는 것만으로는 환기 성능에 미치는 영향은 미비하였다.

불교철학과 대순사상의 사유체계에 대한 일고찰 - 우주관·인간관·이상사회관을 중심으로 - (Reflection on the Thinking System of Buddhist Philosophy and Daesoon Philosophy)

  • 이덕진
    • 대순사상논총
    • /
    • 제20권
    • /
    • pp.223-272
    • /
    • 2009
  • Both Daesoon philosophy and Buddhist philosophy have strong aspirations for establishing a world comprised of human-beings. In other words, Daesoon philosophy and Buddhist philosophy put human-beings in the place of 'subject character(主語的 人格)' instead of 'predicate character(述語的 人格).' This is because a human is the master rather than a guest of the universe and the world. In this regard, it is safe to say that both Daesoon philosophy and Buddhist philosophy have a common goal of reaching 'an infinitely open life managed by a human-being, the master.' Daesoon philosophy and Buddhist philosophy also share the idea that everything in the universe is an organistic world that is closely connected, like a network. In this aspect, the two philosophies consider the whole world rather than the individual, and seek ways for people to live together actively while expanding the scope of community to the world. Even if 'the morality of living together (相生)' and 'the realization of mercy(同體大悲)' are completely different languages on the surface, it is not difficult to understand the homogeneity inherent in such expressions. Daesoon philosophy and Buddhist philosophy show endless reliability towards all humans and are declarative and reasonable, but both herald human beings as eligible to become the main characters of the future world and lead to the birth of independent human beings while inducing them to the highest position in the universe by liberating humans from the limitations they find. 'Heaven on Earth' as stated in Daesoon philosophy refers to an ideal society where humans and God harmonize, and God and humans complement each other. Also, the world will achieve political stability and equality, realizing an economically prosperous world. Furthermore, social justice will be realized and cultural and religious conflicts resolved. As humans acknowledge there is a way to live together in a universal nature, the environmental issue no longer becomes the top priority for human beings and a world where the morals of human beings reach the highest level will be established. From the original Buddhist perspective, King Jeonrhyun, the proxy of Buddha, realizes the ideal of Buddhism in the mundane world. The world controlled by King Jeonrhyun can be described as having liberty, equality, peace, justice, prosperity, morality, order, legality, democracy, welfare, etc. Therefore, the ideal Buddhist world is materially prosperous, physically healthy and socially just, as well as a world where moral maturity and mental freedom are achieved.

  • PDF

What makes Consumers to Prolong their Consumption on Perishable Food beyond Its Expiration Date?

  • Suh, Hyunsuk;Ju, Hyoungjun
    • Asia Marketing Journal
    • /
    • 제15권2호
    • /
    • pp.133-173
    • /
    • 2013
  • Consumers empty perfectly safe to intake perishable foods everyday if they are older than what prints on expiration date. The variation in expiration dating is freshness labeling represented in various terms such as sell by, package, best before, and so on. Regardless of the terms used and meanings are attached, consumers tend to conceive of freshness labeling on food as end of its shelf-life. Consequently, the food waste becomes a big issue for businesses in food sector. In an effort to demonstrate flexibility on this, KFDA(Korea Food & Drug Administration) introduced "best before" date in domestic market place to reduce food waste, based on the food safety test conducted by KCA(Korea Consumer Agency 2009). The results indicated freshness labeling on food should not be considered as the end of its life. Current study examined the underlying mechanisms(i.e. risk perception, self-construals, and indecisiveness) that influence consumers' intention on prolonged consumption of food beyond its stamped date when the KCA test results are shown to them. In addition, the moderating effect of regulatory focus is tested in the causal relationships between underlying mechanisms and different groups of prolonged consumption intention. Study participants are divided into three groups of prolonged consumption intention: no-change, moderate-change, and wide-change. The group with moderate-change in intention being as our point of reference, logistic regression analyses are conducted on 276 sample population. The results indicated that consumers with high source credibility risk are likely to show wide-change in intention on prolonged consumption while physical risk did not show significance. The consumers with independent self-construal are likely to show no-change in intention on prolonged consumption while interdependent self-construal did not show significance. Indecisiveness showed association a group with wide-change in intention on prolonged consumption. The moderating effect of regulatory focus showed valid results in most situations; the promotion-focused consumers showed wide-change in intention, while prevention-focused consumers showed no-change in intention. Furthermore, the moderating effect of promotion-focus showed a dominant position over the causal effect of indecisiveness in which decisive consumers(i.e. no-change in intention); if they are promotion-focused they tend show for the wide-change in intention instead. It is important to note that for those promotion-focused consumers(or situations), promotion-related arguments are more effective, while for those prevention-focused consumers(or situations) prevention- related arguments are more effective means of persuasion.

  • PDF

레이저 센서의 환경적 특성 분석에 기반한 선박 자동계류장치용 변위 및 속도 측정시스템 설계 (Design of a Displacement and Velocity Measurement System Based on Environmental Characteristic Analysis of Laser Sensors for Automatic Mooring Devices)

  • 김진만;김헌희
    • 해양환경안전학회지
    • /
    • 제29권7호
    • /
    • pp.980-991
    • /
    • 2023
  • 항만 내 선박과 부두의 사고를 예방하기 위하여 통항 및 접안 안전성 평가를 통하여 안전한 부두가 건설되어 관리하고 있으나, 선박의 접안 및 계류 과정에서 선박이 부두에 충돌하거나 로프로 인한 인명사고의 발생 등 예측할 수 없는 사고들이 종종 발생한다. 자동계류장치는 선박의 신속하고 안전한 계류를 위한 자동화된 시스템으로 로봇 매니퓰레이터와 흡착 패드로 구성된 탈/부착 메커니즘을 가지고 있다. 본 논문은 자동계류장치의 흡착 패드의 위치 및 속도제어에 필요한 선체와의 변위 및 속도 측정 시스템을 다룬다. 자동계류장치에 적합한 측정 시스템을 설계하기 위하여, 본 논문은 우선 센서의 성능 및 실외 환경적 특성 분석을 수행한다. 다음으로 이러한 분석 결과를 토대로 실외 부두환경에서 설치되는 자동계류장치에 적합한 변위 및 속도 측정시스템의 구성 및 설계 방법에 대해 기술한다. 또한 센서의 측정상태 감지 및 속도 추정을 위한 알고리즘을 제시한다. 제안된 방법은 다양한 속도 구간에서의 변위 및 속도 측정 실험을 통해 그 유용성을 검증한다.

췌십이지장절제술 후 발생한 후기 출혈에서 스텐트-그라프트를 이용한 치료의 장기적 임상, 영상의학적 결과 (Long-Term Clinical and Radiologic Outcomes after Stent-Graft Placement for the Treatment of Late-Onset Post-Pancreaticoduodenectomy Arterial Hemorrhage)

  • 김우진;전창호;권훈;김진혁;전웅배;김석;서형일;김창원
    • 대한영상의학회지
    • /
    • 제82권3호
    • /
    • pp.600-612
    • /
    • 2021
  • 목적 간 기능 검사와 영상 소견을 기반으로 하여 췌십이지장절제술 후 발생한 후기 출혈에서 스텐트-그라프트를 이용한 치료의 장기적 영상의학적, 임상적 경과를 보고자 한다. 대상과 방법 2012년 6월부터 2017년 5월까지 췌십이지장절제술 후 발생한 후기 출혈로 스텐트-그라프트 삽입술을 받은 9명의 환자를 후향적으로 분석하였다. 저자들은 시술 직후 술기적, 임상적 결과와 간 기능 검사를 검토하였다. 스텐트-그라프트의 개통성은 CT angiography를 이용하여 평가하였다. 결과 모든 스텐트-그라프트는 즉각적인 동맥 출혈을 멈추면서 간동맥 혈류를 유지할 수 있도록 의도했던 위치에 배치되었다. 기술적 성공은 모든 9명의 환자에게서 이루어졌다. 8명의 환자는 시술 후 생존하여 퇴원하였으며 한 명의 환자는 시술 28일 후 사망하였다. 평균 추적 관찰 기간은 781일이었다(범위: 28~1766일). 추적관찰 CT angiography에서 모든 환자의 스텐트-그라프트는 폐쇄되었다. 그러나 모든 환자들에서 간 경색을 시사할 만한 혈중 아스파르테이트아미노전달효소나 알라닌아미노전달효소 수치의 증가를 보이지 않았다. 결론 스텐트-그라프트 삽입술은 췌십이지장절제술 후 발생한 생명을 위협하는 후기 출혈의 안전하고 효과적인 치료이다. 간 기능과 간 말단부 동맥혈 공급은 추적관찰 CT상 스텐트-그라프트가 높은 확률로 막힘에도 불구하고 유지된다.

Theoretical analysis of erosion degradation and safety assessment of submarine shield tunnel segment based on ion erosion

  • Xiaohan Zhou;Yangyang Yang;Zhongping Yang;Sijin Liu;Hao Wang;Weifeng Zhou
    • Geomechanics and Engineering
    • /
    • 제37권6호
    • /
    • pp.599-614
    • /
    • 2024
  • To evaluate the safety status of deteriorated segments in a submarine shield tunnel during its service life, a seepage model was established based on a cross-sea shield tunnel project. This model was used to study the migration patterns of erosive ions within the shield segments. Based on these laws, the degree of deterioration of the segments was determined. Using the derived analytical solution, the internal forces within the segments were calculated. Lastly, by applying the formula for calculating safety factors, the variation trends in the safety factors of segments with different degrees of deterioration were obtained. The findings demonstrate that corrosive seawater presents the evolution characteristics of continuous seepage from the outside to the inside of the tunnel. The nearby seepage field shows locally concentrated characteristics when there is leakage at the joint, which causes the seepage field's depth and scope to significantly increase. The chlorine ion content decreases gradually with the increase of the distance from the outer surface of the tunnel. The penetration of erosion ions in the segment is facilitated by the presence of water pressure. The ion content of the entire ring segment lining structure is related in the following order: vault < haunch < springing. The difference in the segment's rate of increase in chlorine ion content decreases as service time increases. Based on the analytical solution calculation, the segment's safety factor drops more when the joint leaks than when its intact, and the change rate between the two states exhibits a general downward trend. The safety factor shows a similar change rule at different water depths and continuously decreases at the same segment position as the water depth increases. The three phases of "sudden drop-rise-stability" are represented by a "spoon-shaped" change rule on the safety factor's change curve. The issue of the poor applicability of indicators in earlier studies is resolved by the analytical solution, which only requires determining the loss degree of the segment lining's effective bearing thickness to calculate the safety factor of any cross-section of the shield tunnel. The analytical solution's computation results, however, have some safety margins and are cautious. The process of establishing the evaluation model indicates that the secondary lining made of molded concrete can also have its safety status assessed using the analytical solution. It is very important for the safe operation of the tunnel and the safety of people's property and has a wide range of applications.

쇄골하정맥을 통한 매립혈액투석카테터 삽입시 상지 거상법의 유용성: 2예 보고 (Placement of a Subclavian Tunneled Hemodialysis Catheter with the Patient's Arm Raised May Reduce the Risk of Complications: Two Cases Report)

  • 유지민;심동재;김도영;백승환;박창숙;이정휘
    • 대한영상의학회지
    • /
    • 제84권2호
    • /
    • pp.477-482
    • /
    • 2023
  • 매립혈액투석카테터 삽입을 위한 접근로 선택에서 쇄골하정맥은 이후에 동정맥루 접근로 형성을 위해 가능한 사용을 피하는 경로이다. 그러나 반복적 삽관으로 접근 가능한 정맥이 소진되거나 기대여명이 길지 않고 응급 투석이 필요한 경우 쇄골하정맥을 선택할 수 있다. 그러나 쇄골하정맥을 통한 혈액투석카테터 삽입에는 기술적인 어려움이 있다. 쇄골하정맥은 종종 상대정맥과 직각을 형성하여 굵은 혈관초삽입시 혈관 손상을 초래할 수 있다. 상지 거상 상태에서 혈관초를 삽입하는 방법은 각도를 완만하게 유도하여 이러한 문제를 극복하는데 도움을 줄 수 있다. 고식적앙와위 자세로 시술 중 상대정맥 손상이 있었던 환자와 연달아 내원하여 상지 거상 후 안전하게 혈액투석카테터를 삽입한 환자의 각각의 증례를 통해 상지 거상법이 도움이 될 수 있음을 보고하고자 한다.

한국 산업간호교육의 변화추세 분석 (Transition of Occupational Health Nursing Education in Korea)

  • 조동란;전경자;김소연
    • 한국직업건강간호학회지
    • /
    • 제6권2호
    • /
    • pp.144-155
    • /
    • 1997
  • In December 1990, Occupational Safety and Health Law was amended to reinforce employer's responsibilities on employees' health and safety. Among the amended law it was important to expand the role of an occupational health nurse to the role of an occupational health manager. An occupational health manager should take charge of coordinating periodic health examination and environmental hazard evaluation, providing primary care, monitoring employees' health status, giving the workplace walk-through, selecting safe protection equipment, providing health information, counseling and health education, independently. This position of occupational health nurse is equivalent to the role of doctors or occupational hygienists. In 1991, government made a master plan to prevent occupational disease and injury. Under the plan, Korea Industrial Nursing Association (KINA) was established in 1994 with the purpose of improving health services and upgrading career opportunities for members. Therefore, this study was designed to analyze the transition of occupational health nursing education with the changes of law and policy in Korea between 1991 and 1996. In details, it was to analyze the rate of school providing occupational health nursing practice based lecture, lecture hours, lecture contents in undergraduate curriculum, program contents of graduate school, kinds of continuing education, etc. For this purpose, we conducted survey two times. In February 1991, baseline study was conducted with all nursing programs in Korea (19 BSN programs and 43 nursing departments of junior college). From April to May in 1996, the second survey was conducted with all nursing programs (38 BSN programs and 69 junior colleges). The first response rate was 66.1% and the second was 40.6%. Structured questionnaires were mailed to the deans or the community health nursing faculties. In the case of graduate school, telephone survey was conducted with 10 school of public health or environmental health area. Data from the yearbook of Industrial Safety Training Institute (ISTI), the history of Korea Industrial Health Association, and the journals of KINA were also included in the analysis. As the results, we found that there were remarkable improvement in undergraduate and graduate programs, obligatory as well as voluntary continuing education in terms of occupational health nursing expertise between 1991 and 1996. 1) The number of school providing occupational health nursing practice-based lecture was increased with the rate from 7.3% to 25.6%. The rate of school giving over 15 class-hours was increased from 33.3% to 46.6%. 2) Content areas were composed of introduction of occupational health, occupational epidemiology, industrial hygiene, occupational disease and injury, law and policy, health education, concept of occupational health nursing, role of occupational health nurse, occupational health nursing process, etc. Of content areas, occupational health nursing process was more emphasized with the increased rate from 43.9% to 88.4%. 3) In the case of graduate school, occupational health programs were increased from 4 to 10. One of them has developed occupational health nursing program as an independent course since 1991. 4) The law increased educational hours from 28 hours to 36 hours for introductory course at the time of appointment, and from 14 hours to 24 hours every 2 years for continuing education. Course contents were Occupational safety and health law, introduction of occupational health, health education methodology, planning and evaluation, periodic health exam, occupational disease care, primary care, emergency care, management, industrial environment evaluation, etc. In 1996, Korea Industrial Nursing Association has begun to provide continuing education after Industrial Safety Training Institute. 5) Various educational programs in voluntary base were developed such as monthly seminar, CE articles, annual academic symposium, etc. It was shown that changes of law and policy led rapid growth of occupational health nursing education in various levels. From this trend, it is expected that occupational health nurse expertise be continuously to be enhanced in Korea. Legal and political supports should proceed for the development of occupational health nursing in early stage.

  • PDF

On-X 기계판막을 이용한 판막치환술의 단기성적분석 (Early Clinical Experience in Valve Replacement Using On-X Prosthetic Heart Valve)

  • 김인섭;김우식;신용철;유환국;김병열;정성철
    • Journal of Chest Surgery
    • /
    • 제37권9호
    • /
    • pp.742-748
    • /
    • 2004
  • On-X 판막은 비교적 최근 소개된 이엽성 기계판막으로 국립의료원에서 시행한 28명의 환자의 단기 임상성적을 통하여 판막의 안정성과 유용성을 보고하고자 한다. 대상 및 방법: 1999년 5월부터 2003년 5월까지 On-X 판막을 이용하여 32예의 판막치환술을 받은 28명의 연속적인 환자를 대상으로 하였으며 승모판막 치환 12예, 대동맥 판막치환 10예 그리고 승모판막 및 대동맥판막치환 6예이었다. 수술 후 발생한 합병증 및 사망률에 대한 정의 및 분류는 심장 판막수술에 대한 AATS/STS 지침에 근거하여 분석하였다. 전체 추적기간은 64환자-년이었고 평균 27개월이었다 결과: 수술 후 30일 이내의 조기 사망률은 7.14% (2/28)이었으며 만기사망은 없었다. 2년 생존율은 전체적으로 92.86$\pm$4.87% 이며 대동맥판막치환술이 90$\pm$9.49%, 이중판막치환술이 83.3$\pm$1.52%, 승모판막치환술이 100%로 나타났다. 혈전 색전증이 가장 많은 합병증으로 2예가 있었으며 모두 승모판막치환 증례에서 발생되어 Linearized Ratio는 총 3.17%/환자-년이었으며 승모판막만을 보면 6.5%/환자-년이었고 항응고제와 관련 된 출혈, 판막폐쇄증, 판막주위누출, 심내막염 등의 합병증의 모든 예에서 발생되지 않아 판막관련 합병증이 없는 2년간의 빈도는 84.85 $\pm$ 10.75% (freedom from valve related complication)이었다. 수술전 NYHA Class III 이상인 증례가 24예(85.71%)이었으나 수술 후에는 NYHA Class I 또는 II에 속하는 증례가 25예로 89.29%를 보였다. 용혈척도로서 혈색소 수치, 혈장 LDH, 망상적혈구수치, 간접 빌리루빈치는 수술 3개월 후 검사에서 모두 정상수치를 보였다. 수술 후 3개월 추적관찰 시 시행한 심초음파상 승모판막의 최대 압력차는 6.1 $\pm$ 1.8 mmHg, 평균 압력차는 3.0$\pm$0.6 mmHg이었고 유효 개구 면적은 판막 직경 27 mm, 29 mm, 31 mm, 33 mm 각각 2.54$\pm$0.56 $m^2$, 2.39 $\pm$0.73 $m^2$, 2.34 $\pm$0.55 $m^2$, 2.40$\pm$0.63 $m^2$이었다. 대동맥판막의 최대 압력차는 21.1$\pm$14.12 mmHg,평균 압력차는 12.3$\pm$6.52 mmHg. 결론: On-X 판막수술 후 사망률, 판막관련합병증, 도플러 심초음파상 다른 판막들과 큰 차이를 보이지 않은 점과 NYHA Class의 호전과 정상수치를 유지하는 용혈지표를 고려한다면 비교적 좋은 결과를 보였으며 증례의 축적과 장기간의 임상분석이 이루어지면 안전하고 유용한 판막으로 입증될 것이라고 생각한다.