• 제목/요약/키워드: Safety drop zone

검색결과 8건 처리시간 0.024초

데이터 기반의 세종시 교통안전망 강화 방안 연구 (Data-based Traffic Safety Strategy for Sejong City)

  • 강현정;김태홍
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2021년도 추계학술대회
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    • pp.147-149
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    • 2021
  • 세종특별자치시의 교통량 폭증으로 인한 교통 문제 증가 추세는 시설 인프라의 투자로는 해결하기 어려운 수준에 이르러 데이터 기반의 지능형 교통환경 구축이 필수적이다. 교통데이터를 활용해 교통안전정책을 수립한 국내·외 사례를 알아보고 세종특별자치시 교통정보 및 데이터 활용 실태 등을 분석하여 CCTV를 활용한 주차정보 제공, 스마트 교통신호제어시스템 구축, 안전지키미 드롭존 설치방안을 제안한다. 본 연구가 향후 세종특별자치시의 교통 안전망 강화 정책 수립의 기반이 되기를 기대한다.

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Centrifuge modeling of dynamically penetrating anchors in sand and clay

  • An, Xiaoyu;Wang, Fei;Liang, Chao;Liu, Run
    • Geomechanics and Engineering
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    • 제30권6호
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    • pp.539-549
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    • 2022
  • Accidental anchor drop can cause disturbances to seabed materials and pose significant threats to the safety and serviceability of submarine structures such as pipelines. In this study, a series of anchor drop tests was carried out to investigate the penetration mechanism of a Hall anchor in sand and clay. A special anchor drop apparatus was designed to model the inflight drop of a Hall anchor. Results indicate that Coriolis acceleration was the primary cause of large horizontal offsets in sand, and earth gravity had negligible impact on the lateral movement of dropped anchors. The indued final horizontal offset was shown to increase with the elevated drop height of an anchor, and the existence of water can slow down the landing velocity of an anchor. It is also observed that water conditions had a significant effect on the influence zone caused by anchors. The vertical influence depth was over 5 m, and the influence radius was more than 3 m if the anchor had a drop height of 25 m in dry sand. In comparison, the vertical influence depth and radius reduced to less than 3 m and 2 m, respectively, when the anchor was released from 10 m height and fell into the seabed with a water depth of 15 m. It is also found that the dynamically penetrating anchors could significantly influence the earth pressure in clay. There is a non-linear increase in the measured penetration depth with kinematic energy, and the resulted maximum earth pressure increased dramatically with an increase in kinematic energy. Results from centrifuge model tests in this study provide useful insights into the penetration mechanism of a dropped anchor, which provides valuable data for design and planning of future submarine structures.

점안용 우황약침액의 안전성 및 유효성 평가 (The Experimental Study of Safety and Efficacy in Using Bovis Calculus Pharmacopuncture Solution as Eye Drop)

  • 서형식
    • 대한약침학회지
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    • 제12권3호
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    • pp.61-72
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    • 2009
  • Objectives : This experimental study was performed to investigate the safety and efficacy of Bovis Calculus pharmacopuncture solution manufactured with freezing dryness method to use eye drop. To identify the use of it as eye drop, the eye irritation test of rabbits and the antibacterial test of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, and Candida albicans were performed. Methods : 1. The eye irritation test of this material was performed according to the Regulation of Korea Food & Drug Administration(2005. 10. 21, KFDA 2005-60). After Bovis Calculus pharmacopuncture solution was administered in the left eye of the rabbits, eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 2. After administering Bovis Calculus pharmacopuncture solution on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis, MIC(Minimum Inhibition Concentration) and the size of inhibition zone were measured. Anti-bacterial potency was also measured using the size of inhibition zone. Results : 1. After Bovis Calculus pharmacopuncture solution was administered in the left eye of the rabbits, it was found that none of nine rabbits have abnormal signs and weight changes. 2. After Bovis Calculus pharmacopuncture solution was medicated in the left eye of the rabbits, no eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 3. There was no response to MIC on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) after Bovis Calculus pharmacopuncture solution was medicated. Conclusions : The present study suggests that Bovis Calculus pharmacopuncture solution is a nontoxic and non-irritant medicine, which does not cause eye irritation in rabbits, but dosen't have antibacterial effects on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis. These study result recommends that more research on other herbal medicines of eye drop for Keratitis are required.

도시고속도로 공사구간의 적정 완화구간 길이 산정 (The Proper Length of Transition Area for Work Zones on Urban Freeways)

  • 이미리;이청원;김도경
    • 대한교통학회지
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    • 제31권4호
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    • pp.58-66
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    • 2013
  • 도시고속도로는 교통량이 많고 주행속도가 높아 도로점용 공사 시 교통사고 위험 뿐만 아니라 차로 수 감소, 차로 변경, 가감속 등의 증가로 마찰이 증대되어 교통정체를 야기한다. 본 연구는 공사구간을 효율적으로 운영관리 하기 위해서 이동성과 안전성의 두 가지 측면을 만족하는 공사구간 적정 완화구간 길이 산정을 목적으로 한다. 분석을 위해 차로수별 3가지 시나리오를 구성하였고, 각 시나리오별로 완화구간 길이를 100-500m까지 100m 간격으로 변화시키며 적정 완화구간 길이를 결정하였다. 그 결과, 편도 3, 4차로 도로의 1차로 점용 공사 시 300m, 편도 2차로 도로의 1차로 점용 공사 시 200m로 나타났다. 편도 차로 수에 따라 동일한 완화구간 길이로 운영하는 것보다는 차로 수에 따라 다르게 운영하는 것이 우수하다는 결과를 도출하였다.

점안용 소염약침액의 안전성 및 유효성 평가 (The Experimental study of safety and efficacy in using Soyeom Pharmacopuncture solution as eyedrops)

  • 강은교;서형식
    • 대한약침학회지
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    • 제12권1호
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    • pp.21-33
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    • 2009
  • Objective : This experimental study was performed to investigate the safety of Soyeom Pharmacopunture solution manufactured by extraction of alcohol and water. To identify the use of it as eyedrops, the eye irritation test of rabbits and antibacterial test of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, and Candida albicans was performed. Methods : 1. The eye irritation test of this material was performed according to the Regulation of Korea Food & Drug Administration(2005. 10. 21, KFDA 2005-60). After Soyeom pharmacopuncture solution was administered in the left eye of the rabbits, eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 2. After administering Soyeom Pharmacopuncture solution on bacterial species (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis, MIC(Minimum Inhibition Concentration) and the size of inhibition zone were measured. Anti-bacterial potency was also measured using the size of inhibition zone. Results : 1. After Soyeom pharmacopuncture solution was administered in the left eye of the rabbits, it was found that none of nine rabbits have abnormal signs and weight changes. 2. After Soyeom pharmacopuncture solution was medicated in the left eye of the rabbits, no eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 3. There was no response to MIC on bacterial species (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) after Soyeom pharmacopuncture solution was medicated. Conclusions : The present study suggests that Soyeom pharmacopuncture solution is a non-toxic and non-irritant medicine, which does not cause eye irritation in rabbits, but dosen't have anti-bacterial effects on bacterial species which cause Keratitis. These study result recommends that more research on other herbal medicines of eye drop for Keratitis are required.

Simulation study on effects of loading rate on uniaxial compression failure of composite rock-coal layer

  • Chen, Shao J.;Yin, Da W.;Jiang, N.;Wang, F.;Guo, Wei J.
    • Geomechanics and Engineering
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    • 제17권4호
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    • pp.333-342
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    • 2019
  • Geological dynamic hazards during coal mining can be caused by the failure of a composite system consisting of roof rock and coal layers, subject to different loading rates due to different advancing velocities in the working face. In this paper, the uniaxial compression test simulations on the composite rock-coal layers were performed using $PFC^{2D}$ software and especially the effects of loading rate on the stress-strain behavior, strength characteristics and crack nucleation, propagation and coalescence in a composite layer were analyzed. In addition, considering the composite layer, the mechanisms for the advanced bore decompression in coal to prevent the geological dynamic hazards at a rapid advancing velocity of working face were explored. The uniaxial compressive strength and peak strain are found to increase with the increase of loading rate. After post-peak point, the stress-strain curve shows a steep stepped drop at a low loading rate, while the stress-strain curve exhibits a slowly progressive decrease at a high loading rate. The cracking mainly occurs within coal, and no apparent cracking is observed for rock. While at a high loading rate, the rock near the bedding plane is damaged by rapid crack propagation in coal. The cracking pattern is not a single shear zone, but exhibits as two simultaneously propagating shear zones in a "X" shape. Following this, the coal breaks into many pieces and the fragment size and number increase with loading rate. Whereas a low loading rate promotes the development of tensile crack, the failure pattern shows a V-shaped hybrid shear and tensile failure. The shear failure becomes dominant with an increasing loading rate. Meanwhile, with the increase of loading rate, the width of the main shear failure zone increases. Moreover, the advanced bore decompression changes the physical property and energy accumulation conditions of the composite layer, which increases the strain energy dissipation, and the occurrence possibility of geological dynamic hazards is reduced at a rapid advancing velocity of working face.

산란계 밀집지역의 산란저하성 질병에 관한 연구 (Studies of the egg drop laying diseases from the mass zone layer)

  • 이정원;엄성심;박인규;배정준;정동석;송희종
    • 한국동물위생학회지
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    • 제28권2호
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    • pp.121-146
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    • 2005
  • Newcastle disease (ND), infectious bronchitis (IB), low pathogenic avian Influenza (LPAI) and fowl typhoid (FT) have been known as egg drop laying diseases because of the serious layer damage from mass zone layer. In this study, such egg drop laying diseases were investigated. To access this study, we peformed to evaluate antibody titers in serum and isolated bacteria and virus from organs and feces on May, July and September in 2003. The distribution of ND from January to May, IB and LPAI from October to February of the next year, and FT from March to September were inspected by the question survey in 21 farms. ND revealed to be positive rates of 490 to 474 $(96.7\%)$ in May, 510 to 506 $(99.2\%)$ in July and 510 to 510 $(100\%)$ in September with hemagglutination inhibition (HI) test. The mean antibody titers were 10.2, 9.9 and 10.2, respectively. With regard to IB, 484 out of 490 samples $(98.7\%)$ in May, 508 of 510 $(99.6\%)$ in July and 509 of 510 $(99.8\%)$ in September showed positive results and the mean antibody titers were gradually increased with 8.2, 9.0 and 9.4, respectively. According to HI test of LPAI, the positive results were shown in 442 of 480 $(92.1\%)$, 394 of 494 $(79.8\%)$ and 402 of 483 $(83.2\%)$ in May, July and September, respectively The mean antibody titers were decreased with 4.6, 4.3 and 4.0. The distribution of LPAI also elicited the positive rates of 480 to 475 $(99.0\%)$ in May, 494 to 485$(98.2\%)$ in July, 483 to 472 $(97.7\%)$ in September as determined by ELISA and the mean S/P ratio were 2.319, 2.557 and 2.380, respectively. Compared ELISA results with HI test of LPAI the positive results were 480 to 422 $(92.1\%),\;475(99.0\%),\;494\;to\;394 (79.8\%),\;485 (98.2\%)\;and\;483\;to\;402(83.2\%),\;472(97.7\%)$. Therefore, the positive rate determined by ELISA was higher than that of HI test with 6.9, 18.4 and $14.5\%$, respectively. When performed RT-PCR for ND using organ and feces samples, the pathotypes were detected $5(15.6\%)\;in\;May,\; 2(5.3\%) in\;July,\;2(7.1\%)$ in September but there is no samples showing positive band for LPAI. In attempt to isolate Salmonella gallinarum, bacteria were obtained from 4 cases (12.5%) in May, 9 (23.6%) in July, 5 (17.8%) in September. Thus the highest rate for isolation revealed to be shown in July When evaluated the antimicrobial susceptibility to 18 isolated strains of 5. gallinarum, bacteria were sensitive to trimethoprim/sulfamethox$(61.1\%),\;kanamycin\;(55.5\%),\;ampicillin\;(55.5\%)$ and amoxacillin/clavulanic acid $(55.5\%)$, cephalothin $(50.0\%)$, but resistant to penicillin $(88.9\%)$, streptomycin $(88.9\%)$, erythromycin $(83_4\%)$ and tetracycline $(61.1\%)$. According to HI test of ND and LPAI using captured 164 wild Korean tree sparrows (Passer nontanus), the positive rates were $47.6\%\;and\;57.3\%$, and the mean HI titers were 5.32 and 4.02, respectively. 71 $(43.2\%)\;and\;58(35.3\%)$ in captured sparrows also showed more than 4 titers for HI test to ND and LPAI, respectively However, the attempt for isolation of viruses failed in all samples.

LNG 저장탱크 내조용 강 용접부의 파괴인성 평가 (Evaluation of Fracture Toughness in Steel Weldment for Inner Wall of LNG Storage Tank)

  • 장재일;주장복;양영철;김우식;홍성호;권동일
    • 한국가스학회지
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    • 제2권1호
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    • pp.7-13
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    • 1998
  • 본 연구에서는 LNG 저장탱크의 안전성을 확보하기 위한 연구의 일환으로서, 실제 탱크의 건설에서와 같은 조건으로 SMAW(Shielded Metal Arc Welding) 방식으로 용접된 $9\%$ Ni강의 X-개선 후판용접부내의 파괴인성의 변화를 평가하고 미세조직을 분석하였다. 이때 파괴인성의 평가는 본 연구자들이 제안한 '개선한 CTOD(crack tip opening displacement) 시험법'으로 행하였으며 열영향부내의 미세조직 및 파면은 광학현미경, 주사전자현미경 및 X-선 회절 분석기로 관찰하였다. 결과로부터 열영향부 내의 CTOD 값은, 평가위치가 용융선(Fusion Line-F.L.)으로 접근할수록 감소하는 경향을 나타내었다. 이는 잔류 오스테나이트의 양이 줄어들고 결정립 미세화 효과가 없어지는 영역인 결정립 조대화영역이 열영향 부내에서 차지하는 분율이 증가함에 따른 것이다. 한편, 잔류 오스테나이트의 열적 안정성이 상대적으로 감소하게 되는 F.L.${\~}$F.L.+3mm에서 온도감소에 따른 인성감소의 정도가 F.L.+5mm${\~}$F.L.+7mm보다 상대적으로 매우 큼을 알 수 있었다.

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