• 제목/요약/키워드: Safety case

검색결과 6,027건 처리시간 0.032초

사면의 안정해석에 관한 연구 (Stability Analysis of the Slopes)

  • 강우욱;조성섭;지인택
    • 한국농공학회지
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    • 제31권1호
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    • pp.58-70
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    • 1989
  • The paper compared the Bishop methed to the Fellenius method in the analysis of slope stability. Laboratory model test was carried out in the case of seepage flow considered. The results obtained from this study were summarized as follows; 1. The slice pieces of 10 were enough to analysis the slope stability. 2. The safety factor. by the Fellenius method was lower than the Bishop method by the 96 to 97% in the case of no seepage flow and by the 95 to 96% in the case of seepage flow considered. 3. Besides the parameter of soil and slope, the safety factor of slope was influenced by the height of slope. This phenomena was distinct in the height of height less than 10 meters. 4. In the case of clay, there was no difference in the safety factor of slope between Fellenius and Bishop rnethod. The safety factors of slope with the seepage flow considered were lower than those with no see-page flow. 5. The influence of cohesion on the safety factor was more significant in the Bishop method than in the Fellenius method. 6. The slope failure of model test of A and B soil samples with high permeability coefficient was taken place slightly in vicinity of toe by the concentration of stress and gradually increased 7. Under condition of same slope height, the shapper the slope, the shorter the radius and the center of critical circle appered downward and finally failure of slope occured inside the slope.

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Integrated control of an air-breathing hypersonic vehicle considering the safety of propulsion system

  • Chengkun, Lv;Juntao, Chang;Lei, Dai
    • Advances in aircraft and spacecraft science
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    • 제10권1호
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    • pp.1-18
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    • 2023
  • This paper investigates the integrated control of an air-breathing hypersonic vehicle considering the safety of propulsion system under acceleration. First, the vehicle/engine coupling model that contains a control-oriented vehicle model and a quasi-one-dimensional dual-mode scramjet model is established. Next, the coupling process of the integrated control system is introduced in detail. Based on the coupling model, the integrated control framework is studied and an integrated control system including acceleration command generator, vehicle attitude control loop and engine multivariable control loop is discussed. Then, the effectiveness and superiority of the integrated control system are verified through the comparison of normal case and limiting case of an air-breathing hypersonic scramjet coupling model. Finally, the main results show that under normal acceleration case and limiting acceleration case, the integrated control system can track the altitude and speed of the vehicle extremely well and adjust the angle deflection of elevator to offset the thrust moment to maintain the attitude stability of the vehicle, while assigning the two-stage fuel equivalent ratio to meet the thrust performance and safety margin of the engine. Meanwhile, the high-acceleration requirement of the air-breathing hypersonic vehicle makes the propulsion system operating closer to the extreme dangerous conditions. The above contents demonstrate that considering the propulsion system safety will make integrated control system more real and meaningful.

Efficacy and Safety of Gabapentin in the Treatment of Chronic Cough: A Systematic Review

  • Shi, Guanglin;Shen, Qin;Zhang, Caixin;Ma, Jun;Mohammed, Anaz;Zhao, Huan
    • Tuberculosis and Respiratory Diseases
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    • 제81권3호
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    • pp.167-174
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    • 2018
  • Despite recent clinical guidelines, the optimal therapeutic strategy for the management of refractory chronic cough is still a challenge. The present systematic review was designed to assess the evidence for efficacy and safety of gabapentin in the treatment of chronic cough. A systematic search of PubMed, Embase, Cochrane Library databases, and publications cited in bibliographies was performed. Articles were searched by two reviewers with a priori criteria for study selection. Seven relevant articles were identified, including two randomized controlled trials, one prospective case-series designed with consecutive patients, one retrospective case series of consecutive patients, one retrospective case series with unknown consecutive status, and two case reports comprising six and two patients, respectively. Improvements were detected in cough-specific quality of life (Leicester Cough Questionnaire score) and cough severity (visual analogue scale score) following gabapentin treatment in randomized controlled trials. The results of prospective case-series showed that the rate of overall improvement of cough and sensory neuropathy with gabapentin was 68%. Gabapentin treatment of patients with chronic cough showed superior efficacy and a good safety record compared with placebo or standard medications. Additional randomized and controlled trials are needed.

ASME 코드 케이스 N-597-2의 직관 국부허용두께의 새로운 제안 (A New Proposal for the Allowable Local Thickness of Straight Pipes in ASME Code Case N-597-2)

  • 박재학;신규인;박치용;이성호
    • 한국안전학회지
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    • 제22권1호
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    • pp.13-18
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    • 2007
  • Structural integrity assessment of thin-walled pipes and pipe items has become one of the major issues in the nuclear power plant. ASME Section XI Code Case N-597-2 provides a criterion for acceptance of the pipes. But the code case has several limitations for application and sometimes gives too conservative or non-conservative results. So it is necessary to understand fully the technical bases of the code case. In the code case N-597, the allowable local thicknesses of thinned straight pipes are given for three different cases. Because of the different technical base, each case gives different thickness values and sometimes gives contradictory values. In this paper attempts were made in order to propose a unified rule for the allowable local thickness and in order to remove or relax the restrictions on the application of the code case. For this purpose elastic stress analyses were made using the finite element method and the stress results were examined. Based on the obtained bending stress results, a very simple procedure was proposed to obtain the consistent allowable local thickness for the thinned straight pipes.

SAFETY MANAGEMENT ON CONSTRUCTION MANAGEMENT: A CASE STUDY REVIEW

  • Eric Chan
    • 국제학술발표논문집
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    • The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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    • pp.249-255
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    • 2011
  • Poor safety management in construction management may adversely affect cost, schedule and quality of a project. Heavy fines upon safety offence becomes a burden to the budget; losing working hours as a result of safety incident impacts on the schedule, and compromising quality is always an indirect consequence when workers perform duties in an unsafe site environment. Therefore, promotion of safety management becomes the top priority in any construction manager's agenda. Working safely will benefit construction project and lead to a "real" success. This paper is a case study, based upon "Geller's 10 principles for achieving a total safety culture", reviewing how a Hong Kong leading construction company fosters the safety culture and possesses a pleasant safety record over years. Its safety performance is not only well ahead the local industry, but also ranges top within the Asia Pacific region and comparable to those mature Western industries. The review concluded that safety culture is one of the major components in construction management and collaboration is the essence to realize this positive culture within an organization. Safety management is not merely a "top down" approach, but requires the positive "bottom up" actions from the other end. The successful story of this company can demonstrate the contribution of safety management in construction management.

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물류 안전과 기업 생산성 향상에 대한 사례 연구 (A case study of logistics safety and enterprise productivity innovation)

  • 김순조;안태용;강경식
    • 대한안전경영과학회지
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    • 제9권5호
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    • pp.7-16
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    • 2007
  • Safety and health problem are essential element of enterprise productivity Innovation within 21th century Global struggle for existence. It is not only to protect workers but it also should prevent workers from various forms of danger. In this paper, specifically, through Case Study about safety and damage government official System course danger exclusion technique of physical distribution, I wish to present direction of continuance possibility management hereafter.

유도탄 사출시 비산물로 인한 인체 안전과 영향성에 관한 연구 (A Study of the Human Body Safety and Effectiveness for Scattering Objects on Missile Ejection Round)

  • 정성학;윤효석
    • 한국안전학회지
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    • 제29권4호
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    • pp.180-183
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    • 2014
  • The purpose of this study is to assess for scattering object for the missile ejection round due to analysis of the human body effectiveness safely. To achieve this goal the measurement method of scattering objects by comparative 2 measurement methods studied, the risk of scattering of the object is evaluated. Result of this study, applied in Europe and Japan, based on the safety criteria for the human body effectiveness when missile ejection round. data showed is not effectiveness to the operator's body safely. Data showed that satisfies the safety criteria for missile ejection round in Europe and Japan through the similarity for the case studies. In case of these safety criteria does not exist regulation in South Korea, this study will be referred as guidelines are considered.

와이어 로프의 파단특성에 관한 실험적 연구 (An Experimental Study on the Fracture Characteristics of Wire Ropes)

  • 김종현;이근오;태순호
    • 한국안전학회지
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    • 제9권4호
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    • pp.3-10
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    • 1994
  • This study examines fracture characteristics of wire rope of 6$\times$37+FC 14mm B degree, Which has been widely used for the strength support for machinery, cranes and shipping. The examination Is based on the fellowing experimental conditions. Firstly, this study analyzes the effect of the strength of wlre rope. When number of broken wires is occuring at the level of 5%, 10% and 15% degree respectively in the following two cases:1) Case of broken down to each strand equally. 2) Case of broken down to one strand only. Secondly, this study analyzes the effect of corrosion on the strength of wire rope. Corrosion times are 72hours, 144hours and 216hours corrosion respectively under following conditions. 1) Case of only a corrosion without wire breaking. 2) Case of corrosion after 5% degree wire breaking to each strand equally. Some outcomes of these experiment are as follows. 1) From the of tension test, We can find that the ratio of strength reduction case of wire broke down to one strand concentrically is greater than that ratio case of broke down to each strand equally. 2) From the corrosion test, We can also find that the ratio of strength reduction case of corroded after 5% degree wire breaking to each strand equally Is greater than that ratio case of corroded without wire breaking. 3) After comparing theoretical fracture load of wires with experimental fracture load of wires, we can find the fracture load of the case of broken down to each strand equally is most similar to theoretical fracture load. 4) It is proposed that safety rules on wire rope in the Industrial safety and healthy labor of law have to change “breaking over 10% of number of wires in one strand of wire rope(excluded filler wire )”has to be replaced by“breaking over 10% of number of all wires in all strand of wire rope(excluded filler wire)”

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A Case Series of Ingested Open Safety Pin Removal Using a Proposed Endoscopic Removal Technique Algorithm

  • Demiroren, Kaan
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제22권5호
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    • pp.441-446
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    • 2019
  • Purpose: Safety pin ingestion is common in some regions of the world and may lead to severe morbidity and mortality. The aim of this study was to present some practical suggestions for ingested safety pins using an accompanying algorithm, presented for the first time in the literature to the best of our knowledge. Methods: Twenty children with ingested safety pins during a 4-year period were retrospectively included in the study. Results: Median age of patients was 9.5 months (interquartile range, 6.3-14 months), and 70% were girls. On endoscopic examination, safety pins were observed in the stomach (25%), duodenal bulb (20%), upper esophagus (15%), middle esophagus (10%), and second part of the duodenum (10%) but were not observed in 20% of the cases. Safety pins were removed using endoscopy in 15 cases (75%). In four cases (20%), no safety pin was observed on endoscopic examination. In one case (5%) involving a 6-month-old infant, the safety pin could not be removed although it was observed using endoscopy. No surgical intervention was needed for any patient. No complications such as perforation or deaths developed, except for erosions, due to the foreign body removal procedure. Conclusion: Safety pins are easily removed endoscopically. The best option is to remove the safety pin using endoscopy while it is still in the esophagus and stomach. For this reason, endoscopic procedures should be performed as soon as possible in children who have ingested safety pins.

머신러닝/ADAS 정보 활용 충돌안전 제어로직 개발 (Development of Collision Safety Control Logic using ADAS information and Machine Learning)

  • 박형욱;송수성;신장호;한광철;최세경;하헌석;윤성로
    • 자동차안전학회지
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    • 제14권3호
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    • pp.60-64
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    • 2022
  • In the automotive industry, the development of automobiles to meet safety requirements is becoming increasingly complex. This is because quality evaluation agencies in each country are continually strengthening new safety standards for vehicles. Among these various requirements, collision safety must be satisfied by controlling airbags, seat belts, etc., and can be defined as post-crash safety. Apart from this safety system, the Advanced Driver Assistance Systems (ADAS) use advanced detection sensors, GPS, communication, and video equipment to detect the hazard and notify driver before the collision. However, research to improve passenger safety in case of an accident by using the sensor of active safety represented by ADAS in the existing passive safety is limited to the level that utilizes the sudden braking level of the FCA (Forward Collision-avoidance Assist) system. Therefore, this study aims to develop logic that can improve passenger protection in case of an accident by using ADAS information and driving information secured before a collision. The proposed logic was constructed based on LSTM deep learning techniques and trained using crash test data.