• Title/Summary/Keyword: School Safety

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A Comparative Study on the Legal System of Building a Rooftop Gardening between Korea and China (한국과 중국의 옥상녹화 제도 비교연구)

  • Zhao, Hong-Xia;Kang, Tai-Ho
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.4
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    • pp.11-17
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    • 2011
  • This study focused on the regulations and support system of green rooftop landscaping between Korea and China. Our research found out regulations and support system to review the supplement point to understand the present state of green rooftop landscaping in the two countries. We aimed to provide basic legal information for the development of green rooftop landscaping regulations. Also, a management plan guide and after-evaluation guide were suggested. First, roof load safety is the foremost factor for the structure of green rooftop landscaping. It includes not only considering the weight of construction materials, but also accurately calculating weight of rain, snow and the rooftop's capacity for people when the rooftop is designed. Second, the appropriate waterproof and root material should be selected basing on climatic conditions. Third, a maintenance and management plan needs to be established to regularly check the plant, facilities, soil and to maintain them. Fourth, the criteria of quality inspection are waterproof and root resistant material, and the growth and development of plants. Waterproof and root resistant materials are a very important part of rooftop greening, so they must be strictly inspected after construction. Fifth, the support system of rooftop greening should be continuously improved. The choice of the object and the amount of support should be strictly stipulated so that the construction of rooftop is promoted when volunteers do rooftop greening.

A Study on the Relationship between Ship Stability and Maneuverability Using Free Running Model Experiments (자유항주 모형실험에 의한 선박의 복원성능과 조종성능 관계 연구)

  • Choe, Bo-Ra;IM, Nam-Kyun
    • Journal of Navigation and Port Research
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    • v.40 no.6
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    • pp.353-360
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    • 2016
  • The International Maritime Organization (IMO) has issued international standards for ship maneuverability and stability. These have been established to improve marine safety and influence the direction of research. The previous literature has been researched, but there are few studies on the relationship between ship maneuverability and stability. This study carried out a fundamental experiment to quantitatively evaluate that relationship. Radius of turn and maximum heel angle depending on changing were analyzed through a turning test using a free running model ship. The test results show the change tendency of decreasing turn radius and increasng maximum heel angle according to a GM decrease. A rough estimate equation is proposed to predict the change tendency on radius of turn and angle of maximum heel as GM decreases. Many ships can suddenly experience reduced GM due to unexpected reasons during sailing. The results in this study can be used as fundamental data to estimate a ship's tactical turn diameter and variable heel angle for steering as GM decreases.

Study on Optimization of Detection System of Prompt Gamma Distribution for Proton Dose Verification (양성자 선량 분포 검증을 위한 즉발감마선 분포측정 장치 최적화 연구)

  • Lee, Han Rim;Min, Chul Hee;Park, Jong Hoon;Kim, Seong Hoon;Kim, Chan Hyeong
    • Progress in Medical Physics
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    • v.23 no.3
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    • pp.162-168
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    • 2012
  • In proton therapy, in vivo dose verification is one of the most important parts to fully utilize characteristics of proton dose distribution concentrating high dose with steep gradient and guarantee the patient safety. Currently, in order to image the proton dose distribution, a prompt gamma distribution detection system, which consists of an array of multiple CsI(Tl) scintillation detectors in the vertical direction, a collimator, and a multi-channel DAQ system is under development. In the present study, the optimal design of prompt gamma distribution detection system was studied by Monte Carlo simulations using the MCNPX code. For effective measurement of high-energy prompt gammas with enough imaging resolution, the dimensions of the CsI(Tl) scintillator was determined to be $6{\times}6{\times}50mm^3$. In order to maximize the detection efficiency for prompt gammas while minimizing the contribution of background gammas generated by neutron captures, the hole size and the length of the collimator were optimized as $6{\times}6mm^2$ and 150 mm, respectively. Finally, the performance of the detection system optimized in the present study was predicted by Monte Carlo simulations for a 150 MeV proton beam. Our result shows that the detection system in the optimal dimensions can effectively measure the 2D prompt gamma distribution and determine the beam range within 1 mm errors for 150 MeV proton beam.

A Study on the Weight-Reduction Design of High-Speed Maglev Carbody made of Aluminum Extrusion and Sandwich Composite Roof (알루미늄 압출재와 샌드위치 복합재 루프를 적용한 초고속 자기부상 열차의 차체 경량화 설계 연구)

  • Kang, SeungGu;Shin, KwangBok;Park, KeeJun;Lee, EunKyu;Yoon, IllRo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.10
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    • pp.1093-1100
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    • 2014
  • The purpose of this paper is to suggest a weight-reduction design method for the hybrid carbody of a high-speed maglev train that uses aluminum extrusion profiles and sandwich composites. A sandwich composite was used on the roof as a secondary member to minimize the weight. In order to assemble the sandwich composite roof and aluminum extrusion side frame of the carbody using welding, a guide aluminum frame located at the four sides of the sandwich composite roof was introduced in this study. The clamping force of this guide aluminum frame was verified by three-point bending test. The structural integrity and crashworthiness of the hybrid carbody of a high-speed maglev train were evaluated and verified according to the Korean Railway Safety Law using a commercial finite element analysis program. The results showed that the hybrid carbody composed of aluminum extrusion frames and a sandwich composite roof was lighter in weight than a carbody made only of aluminum extrusion profiles and had better structural performance.

Study on activities of some occupational health nurses in Kyungnam area (경남지역 일부 산업간호사의 업무수행에 관한 연구)

  • Kim, Young-Sook;Shon, Hae-Sook;Kang, Jeong-Hak;Lee, Chang-Hee;Lee, Chae-Un
    • Journal of Preventive Medicine and Public Health
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    • v.28 no.3 s.51
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    • pp.576-587
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    • 1995
  • Authors purposed to observe activities of occupational health nurses and it's related factors, and to suggest the way that induct better occupational health nurses' activities with questionaire to 87 occupational health nurses who individually work as health manager in the plant. The questionaire included type of plant and number of workers, general characteristics, work conditions, activities, etc. Major findings are as follows. 1. 82.8% of occupational health nurses were third decade. 93.1% graduated junior college or college. And 82.8% were not married. 2. General work conditions: 40.2% were belonged to safety-health section, 98.85% were mere clerks. 60.9% worked less than weekly 44 hours, and an annual salary of 50.6 % was between 10 million and 14 million won. 3. Work condition related to health manager work: there was separated health care room in 94.3%, working period as health manager(occupational health nurse) was less than 5 years in 70.1%, 49.4% had the out-of-health manager work. In 87.4%, occupational physician was appointed, only 6.9% of them were full time, 52.9% of them worked little in the plants. The problems related to workers' health were discussed with industrial nurses in 88.5%. 4. Attitude for their work: 88.5% were thought that their work is important for workers' health care, 57.5% satisfied to work as health manager. In 51.7%, motive to being industrial nurse were the appropriate aptitude. 5. Activities: General medical care in 100% were carried out, in 97.7% works related to general health examination, in 100% works related to special health examination were carried. But works related to use of protective apparatus were carried out in 20.8%. 6. Factors related to level of activities: In cases who solved the health related problems by themselves, the level of activites was significantly higher than in others. In cases there were full time occupational physician, the level of activities was significantly lower. 7. Occupational health nurse's needs: 100% wanted regular education, 89.7% wanted the qualifying examination. As the results, author suggests that the right of self-control is given to occupational health nurses and the work of occupational physician is clearly defined for the induction of the better activities of occupational health nurses.

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Moxibustion for Benign Prostatic Hyperplasia: A Systematic Review and Meta-analysis (전립선 비대증에 대한 뜸치료의 효과 : 체계적 문헌고찰과 메타분석)

  • Bae, Go-eun;Lee, Seung-hwan;Hong, Jin-woo;Lee, In;Kim, So-yeon;Choi, Jun-young;Han, Chang-woo;Yun, Young-ju;Park, Seong-ha;Kwon, Jung-nam
    • The Journal of Internal Korean Medicine
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    • v.39 no.3
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    • pp.372-388
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    • 2018
  • Objective: This study evaluates the effectiveness and safety of moxibustion for benign prostatic hyperplasia (BPH). Methods: Using the keywords "benign prostatic hyperplasia", "benign prostatic hypertrophy", "benign prostatic enlargement", "prostatic hyperplasia", and "moxibustion", we searched papers in numerous databases, including National Discovery for Science Leaders (NDSL), Korean Traditional Knowledge Portal (KTKP), Oriental Medicine Advanced Searching Integrated System (OASIS), Research Information Sharing Service (RISS), PubMed, Embase, and CENTRAL. The search range included randomized controlled trials (RCTs). Papers not matched with inclusion criteria were excluded. The methodological quality of each RCT was assessed using the Cochrane risk-of-bias tool. Where appropriate, meta-analyses were performed. Results: Initially, 77 studies were found. Of these, 11 duplicate studies were removed and 27 were excluded following title and abstract screening. After the remaining 39 papers were scanned, 13 RCTs were selected and analyzed. Among these 13 RCTs, five compared moxibustion therapy and oral medication, seven compared moxibustion plus acupuncture therapy and oral medication, and one compared moxibustion plus acupuncture therapy and sham-moxibustion. The meta-analysis showed positive results for the use of moxibustion therapy in terms of International Prostate Symptom Score (IPSS), Quality Of Life (QOL), Maximum Flow Rate (Qmax), Prostate Volume (PV), and the efficacy rate. The meta-analysis showed positive results for the use of moxibustion plus acupuncture therapy in terms of IPSS, QOL, and the efficacy rate. Conclusions: This meta-analysis of clinical trials suggests that moxibustion is effective intreating BPH patients. The results of this study could be applied to clinical treatment of BPH. However, additional large-scale clinical researches should be conducted.

Preliminary Assessment of Groundwater Artificial Recharge Effect Using a Numerical Model at a Small Basin (수치모델을 이용한 소분지에서의 지하수 인공함양 효과 예비 평가)

  • Choi, Myoung-Rak;Cha, Jang-Hwan;Kim, Gyoo-Bum
    • The Journal of Engineering Geology
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    • v.30 no.3
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    • pp.269-278
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    • 2020
  • In this study, the effects of groundwater artificial recharge through vertical wells in the upper small basin are preliminarily evaluated by using field injection test and a 3-D numerical model. The injection rate per well in a model is set to 20, 37.5, 60, and 75 ㎥/day based on the results of field injection test, groundwater levels, and hydraulic conductivities estimated from particle size analysis, and a numerical model using MODFLOW is conducted for 28 cases, which have diverse injection intervals, in order to estimated the changes of groundwater level and water balance after injection. Groundwater level after injection does not show a linear relationship with the injection rate per well, and the cumulative effect of artificial recharge decreases and the timing of maximum water level rise is shortened as the injection interval becomes longer. In four cases of continuous injection with total injection rate of 1,200 ㎥, it is revealed that the recharge effect is analyzed as 36.5~65.3% of the original injection rate. However, it will be more effective if the artificial recharge system combined with underground barrier is introduced for the longer pumping during a long and severe drought. Additionally, it will be possible to build a stable artificial recharge system by an establishment of efficient scenario from recharge to pumping as well as an optimization of recharge facilities.

The study on interval calculation of cross passage in undersea tunnel by quantitative risk assesment method (해저철도터널(목포-제주간) 화재시 정량적 위험도 평가기법에 의한 피난연결통로 적정간격산정에 관한 연구)

  • Yoo, Ji-Oh;Kim, Jin-Su;Rie, Dong-Ho;Shin, Hyun-Jun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.17 no.3
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    • pp.249-256
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    • 2015
  • Quantitative Mokpo-Jeju undersea tunnel is currently on the basis plan for reviewing validation. As for the cross section shape for express boat of 105 km line, sing track two tube is being reviewed as the Euro tunnel equipped with service tunnel. Also, 10 carriage trains have been planned to operate 76 times for one way a day. So, in this study, quantitative risk assessment method is settled, which is intended to review the optimal space between evacuation connection hall of tunnel by quantitative risk analysis method. In addition to this, optimal evacuation connection hall space is calculated by the types of cross section, which are Type 3 (double track single tube), Type 1 (sing track two tube), and Type 2 (separating double track on tube with partition). As a result, cross section of Type 2 is most efficient for securing evacuation safety, and the evacuation connection space is required for 350 m in Type 1, 400 m in Type 2, and 1,500 m in Type3 to satisfy current domestic social risk assessment standard.

Gas/particle Partitioning of PAHs Segregated with Particle Size in Equilibrium States (대기 중 PAHs의 입경별 가스/입자 분배평형에 관한 연구)

  • Park, Jin-Soo;Lee, Dong-Soo;Kim, Jong-Guk
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.12
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    • pp.1270-1276
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    • 2005
  • When gas/particle partitioning of PAHs in the atmosphere approached an equilibrium state, the slope of linear regression between gas/particle partitioning coefficient($logK_p$) and subcooled liquid vapour pressure($logP_L^O$) was -1. But it was alleged that the slope of equilibrium state might not be -1 in real atmospheric environment due to heterogeneous characteristics of particulate matter. In This study, it would be found if gas/particle partitioning of PAHs segregated with particle size in equilibrium state was based on the hypothesis mentioned above. We have calculated the slopes of $logK_p$ v.s. $logP_L^O$ after collecting 10 set samples which consisted of particulate and vaporous phases. The slope was close to -1 in equilibrium states. But despite of equilibrium state, all slopes segregated with particle size were not close to -1 and those were gentler with larger particle size. The difference of slopes in equilibrium states was almost against the assumption of gas/particle partitioning theory. When the gas/particle partitioning was due to adsorption, the desorption enthalpy was different in each particle size. When it was absorption, the activity coefficient was different. The difference of desorption enthalpy and activity coefficient in each particle size indicate the heterogeneous characteristics of the bulk particle. This may be the reason for slope variation with particle size even though in an equilibrium state.

Methodology of Shape Design for Component Using Optimal Design System (최적설계 시스템을 이용한 부품에 대한 형상설계 방법론)

  • Lee, Joon-Seong;Cho, Seong-Gyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.672-679
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    • 2018
  • This paper describes a methodology for shape design using an optimal design system, whereas generally a three dimensional analysis is required for such designs. An automatic finite element mesh generation technique, which is based on fuzzy knowledge processing and computational geometry techniques, is incorporated into the system, together with a commercial FE analysis code and a commercial solid modeler. Also, with the aid of multilayer neural networks, the present system allows us to automatically obtain a design window, in which a number of satisfactory design solutions exist in a multi-dimensional design parameter space. The developed optimal design system is successfully applied to evaluate the structures that are used. This study used a stress gauge to measure the maximum stress affecting the parts of the side housing bracket which are most vulnerable to cracking. Thereafter, we used a tool to interpret the maximum stress value, while maintaining the same stress as that exerted on the spot. Furthermore, a stress analysis was performed with the typical shape maintained intact, SM490 used for the material and the minimizing weight safety coefficient set to 3, while keeping the maximum stress the same as or smaller than the allowable stress. In this paper, a side housing bracket with a comparably simple structure for 36 tons was optimized, however if the method developed in this study were applied to side housing brackets of different classes (tons), their quality would be greatly improved.