• Title/Summary/Keyword: force support system

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Evaluation of Structural Stability of JIB Crane for a Feed Vessel According to the Luffing Angle (러핑각도에 따른 선박용 지브크레인의 구조 안정성 평가)

  • Lee, M.J.;Han, D.S.;Han, G.J.
    • Journal of Power System Engineering
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    • v.12 no.6
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    • pp.24-28
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    • 2008
  • It expects demand of ships which equipped with JIB crane growth to continue. However, demand of JIB crane is increased, domestic shipment company imitated the design of Europe and Japan. And we need to develop the functional system of the JIB crane and modernize it. We need to find the optimum luffing angle for saving energy when JIB crane works. This study analyzed buckling load of JIB and reaction force of support point and stress of JIB according to the luffing angle through finite element analysis when JIB crane loads 40 ton weight. And this study considered the safety factor 1.8 of material. Every design condition was KS A1627 standard. This study used ANSYS 10.0.

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Development of Buffer frame for ATV (ATV용 완충 프레임의 개발)

  • Kim, Joon-An;Jun, Jae-Uhk;Ko, Sung-Woo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.6
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    • pp.159-164
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    • 2011
  • This paper is about the frame for an all terrain vehicle(ATV). An all terrain vehicle, also known as an ATV, has a seat designed to comfortably accommodate a rider over a wide variety of rugged terrain. This study developed and evaluated a buffer system to drive safely and reduce impact force on the load. The Frame includes a main frame portion which has one or more support frames. The buffer system with a double cushion system, one or more of the interaction of the shock absorber is constructed. The 3D modeling of ATV frame is built up with the software CATIA. According to the designing requirement, we analyzed the stress and the deformation of the frame.

Effects of Microgravity on Human Physiology

  • Nguyen, Nguyen;Kim, Gyutae;Kim, Kyu-Sung
    • Korean journal of aerospace and environmental medicine
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    • v.30 no.1
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    • pp.25-29
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    • 2020
  • Space exploration is one of the dreams of humankind. However, the intriguing environment was a challenge for the human body, where we must counter with many extreme conditions such as thermal support, radiation, microgravity. Life, as well as the human body, developed and evolved in the continuous presence of gravity, especially when living creatures transfer from the ocean to the land. Once this gravitational force doesn't impact on the body, the drastic changes occur. Some of these changes were observed immediately, while others progress only slowly. Since the first orbital flight was performed, several hazards for the organs of the human body were identified [1]. These changes in human physiology can reverse when astronauts return to Earth. This article will review the published findings of the effects of microgravity exposure on the human body.

The Opportunity for Educational Innovations and Requirements in Academic System Reform of Medical Schools (의과대학 학제 개편이 필요한가: 학제 개편이 교육 혁신의 동력이 되기 위한 조건)

  • Bo Young Yoon
    • The Korean Journal of Medicine
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    • v.99 no.3
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    • pp.123-126
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    • 2024
  • The amendment to the Higher Education Act enforced on February 20, 2024, abolishing the traditional 2-year pre-med and 4-year medical school programs, marks a significant shift in medical education in Korea. The academic system reform is expected to be a driving force for large-scale curriculum revision, presenting an opportunity to introduce new educational innovations not only in curriculum but also in student assessment and support systems. Addressing these challenges requires collaborative efforts among educators, students, and communities to navigate the evolving landscape of medical education effectively. In this regard, I will illustrate the recruitment and development of educators to implement the reform and the collaboration between communities and medical schools to innovate medical education.

A Case Study on the effects of Elephant Foot Method considering the rate of Changes in Tunnel Cross Section (터널 단면적 변화를 고려한 각부보강 영향성 평가)

  • Lee, Gil-Yong;Oh, Hyeon-Mun;Cho, Kye-Hwan;Oh, Jeong-Ho;Kim, Jong-Ju;Kim, Yong-Seong
    • Journal of the Korean Geosynthetics Society
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    • v.17 no.1
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    • pp.111-118
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    • 2018
  • In case of excavation of the tunnel under weak ground conditions, such as fault zone, leg pile reinforcement with the purpose of suppressing tunnel crown settlement and side wall displacement is commonly applied. There are convergence, crown settlement, leg settlement, and the axial force of leg as a main factor for confirming the safety of support considering the installation angle and length of leg pile reinforcement according to the increase in rate of change of tunnel cross-section. In particular, the influence of right corner settlement, among variables for safety confirmation during excavation, has been analyzed as the dominant factor in the most important priority management showing larger displacement tendency than the increase in rate of the cross-section. And, it was analyzed that the occurrence tendency of axial force on leg pile reinforcement showed the influence of behavior according to the friction support concept mechanism of the pile reinforcement rather than the increase in rate of tunnel cross-section, as it showed a small increase compared to the increase rate of the tunnel cross-section which did not show a great correlation from the viewpoint of the change of the axial force by the length of each leg pile reinforcement with regards to the change in rate of increase in tunnel cross-section. If a certain length of the leg pile reinforcement is selected based on the above grounds, even if the cross-section of the tunnel in poor ground condition is somewhat larger, it has been proved to be a more reasonable method considering the workability and economical efficiency by not extending the length of the leg pile reinforcement by force.

Health and Safety Management Issues of Migrant Workers in Manufacturing Industries and Workplace Enhancement (제조업사업장 외국인근로자 안전관리 실태와 개선방안연구)

  • Kawshalya, Mailan Arachchige Don Rajitha;Weerasinghe, S.D.N.A.M. Amila Madhushanka;Kim, Sang-Hoon;Lim, Hyung-Duk
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.2_2
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    • pp.257-262
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    • 2022
  • With the shortage of labor force in small and medium-size industries, the Korean Employment Permit System (EPS) continues to bring migrant workers. However, the question remains of the health and safety management of their migrant workers. Considering that a significant part of safety and health problems are caused by migrant workers due to a lack of information on identifying risk and inexperience in the field. Telephone interviews were conducted to investigate the migrant workers' perspectives on workplace safety practices. The survey focused on workers' accident histories, understanding of safety practices, and responding to industrial accidents. A total of 66 accidents occurred among 30 participants. 10 accidents were not reported to the employer (company), which the foreign workers judged to be minor injuries that should not be reported as accidents. 80.0% of the participants expressed dissatisfaction with the PPE they were using. Among various reasons lack of understanding due to language barriers, lack of awareness of the importance of safety, communication difficulties were major reasons for the caused accidents and potential health issues. It is necessary to improve the safety and health support system by providing practical support through specialized educational institutes with experts in the field. A legal framework and a proper safety management system need to be maintained. This study suggests changing the current policy to improve the health and safety of migrant workers by, establishing specialized educational institutes with locally grown foreign experts in the field.

Stability Analysis and Design of the Pretension Soil Nailing System (프리텐션 쏘일네일링 시스템의 안정해석 및 설계)

  • Park Si-Sam;Kim Hong-Taek;Choi Young-Geun
    • Journal of the Korean Geotechnical Society
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    • v.20 no.7
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    • pp.197-206
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    • 2004
  • The ground anchor support system may not be occasionally used because of space limitations in urban excavation sites nearby the existing structures. In this case, soil nailing system with relatively short length of nails could be efficiently adopted as an alternative method. The general soil nailing support system, however, may result in excessive deformations particularly in an excavation zone of the existing weak subsoils. Pretensioning the soil nails then could play important roles to reduce deformations mainly in the upper part of the nailed-soil excavation system as well as to improve local stability. In this study, a newly modified soil nailing technology named as the PSN (Pretension Soil Nailing), is developed to reduce both facing displacements and ground surface settlements in top-down excavation process as well as to increase the global stability. Up to now, the analytical procedure and design technique are proposed to evaluate maximum pretension force and stability of the PSN system. Also, proposed are techniques to determine the required thickness of a shotcrete facing and to estimate probability of a failure against the punching shear, Based on the proposed procedure and technique, effects of the radius of a influence circle and dilatancy angle on the thickness of a shotcrete facing, bonded length and safety factors are analyzed. In addition, effects of the reduction of deformations expected by pretension of the soil nails are examined in detail throughout an illustrative example and the $FLAC^{2D}$ program analysis. And a numerical approach is proposed PSN system using the shear strength reduction technique with the $FLAC^{2D}$ program.

Free congregate site meal service systems for elderly at urban area (도시지역 노인을 위한 무료 급식시설의 급식 서어비스 현황조사)

  • Lee, Young-Mee;Lee, Ki-Wan;Myung, Choon-Ok;Park, Young-Sim;Nam, Hae-Won
    • Journal of the Korean Society of Food Culture
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    • v.14 no.4
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    • pp.431-446
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    • 1999
  • The purpose of this study is to examine current foodservice management practices at free congregate meal service for elderly people. Forty seven meal service centers as well as randomly selected Seoul and Kyunggido area were surveyed and interviewed and results were summarized as follows: The cost of each meal(lunch) was ranged from 1,300 won to 1,500 won and 68% of target centers were severed over 100 meals per day. Meal time for lunch begins from 10:30 am to 12:00 because great portion of elderly didn't take breakfast frequently. 52.3% of centers severed meal 5 times per week, just weekdays. 21.3% of centers employeed dietitian, 63.8% of center employeed cook. 95.7% of center were supported labor force by volunteers. Volunteer was important contribution to free meal service. Utilizing the labor force more effectively is thus a major challenge facing manager in each center. Ideal supporting system of free foodstuff, foodbank was still minor source of securing foodstuff. Most of centers(46 centers)served lunch, only one of them served breakfast and lunch. Government was the major financial sponsor, the second of them was religious organization. The large portions of financial support provided only food cost of total meal service budget. Most of center adapted self-service system. Standardized recipes were not developed and meal preparation was controlled under the experience of volunteers. Recording system of nutrition management, production control, storage and inventory control was not adapted by most of sites. It is suggested that in order to meet the change of the patterns of social and family structure, the service of the center should be offended in urban area and it is necessary to develop systematic management models for the center. It was suggested that not only financial support but also systematical support on management by the local government may be necessary to meet the goal of supply nutritionally balanced food at center.

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A scheme on strengthening of R.O.K reserved force (예비전력 정예화 방안)

  • Kim, Jae-Sam
    • Journal of National Security and Military Science
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    • s.5
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    • pp.1-45
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    • 2007
  • Reserved forces of ROKA are in charge of replacement of TOE in the wartime and mission of rear area operation. But there is institutional inertia in the law and organization oriented to fill human resources rather than take mission. We need to prepare for the investment and arrangement of reserved forces as military power that would be replaced standing forces. In this portion, to reinforce reserve forces elite, First, efficient mobilization regulations and systems are suggested. I covered a maintenance of relevant mobilization ordinances which need to legislated and approved by national assembly for wartime and development of mobilization system which might lose the appropriate time for mobilization due to complicated declaration procedures and measures to overcome the panic at the initial stage of the war and organization and employment of nationwide transportation system and mobilization center. To ensure efficient resource management and mobilization of reserve forces with a number of approximately 3 million, there's a necessity of organization for integration and conciliation. To make it real, I suggested establishing and employing the mobilization center, on first phase, employ the mobilization center focusing on homeland divisions, on second phase, it is advisable to convert to national level mobilization system and develop to central mobilization center focusing on national emergency planning committee. During peacetime, in conjunction with Mobilization Cell, mobilization center can conduct resource survey and integrate and manage mobilization resources and take charge of mobilization training of subordinate units, and during wartime, in conjunction with mobilization coordination team and Cell, can ensure the execution of mobilization. Second, Future oriented reserve forces management system such as service system of reserve forces and support system of homeland defense operations. Current service and trainings of reserve forces by the year have very low connection, as it is very complex to manage the resources and trainings, and service and training lack the equity, re-establishment of service system is required. Also in an aspect of CSS and cultivation support for reserve forces, as the scope and limitation of responsibility between the armed forces and autonomous organization is obscure, conditions to conduct actual-fighting exercises are limited. Concentrated budgetting is extremely difficult because reserve forces training fields are scattered nationwide, and facilities and equipments are rapidly getting older. To improve all these, I suggest the organization of homeland defense battalion with a unit of "City-Gun-District" and supporting the local reserve forces. Conduct unit replacement or personal replacement for those who have finished their 1 or 2 years and homeland defense operation duty for those with 3-5 years for consistency and simplification. Third, I suggest Future oriented Reserved Training(FRT) and Training Center oriented training management to establish a reliable reserve training. Reserves carry out expansion of unit, conventional combat mission, homeland defense and logistics support during wartime, and actual-fighting exercise, and disaster relief, peace keeping activities. Despite diverse activities and roles, their training condition still stays definitely poor. For these reasons, Modernization of weapons and facilities through gradual replacement and procurement is essential to enhance mobilization support system.

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Analysis of Moving Vehicle Load Distribution of Curved Steel Box Girder Bridges considering Various Support Conditions (곡선교의 받침특성에 따른 주행차량하중분배 특성분석)

  • Kim, Sang Hyo;Lee, Yong Seon;Cho, Kwang Yil
    • Journal of Korean Society of Steel Construction
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    • v.14 no.6
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    • pp.711-720
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    • 2002
  • A 3-D numerical model, which could demonstrate the static and dynamic responses of a curved bridge more precisely with the moving vehicles, was developed The dynamic response induced by the centrifugal rolling motion of vehicle was identified according to the variations of the partial grade and the curvature of the slab. Dynamic characteristics of the curved bridge with the moving vehicle were analyzed under the condition of support types and two different support systems. Parametric studies were conducted to compare the efficiency of load distribution in the curved bridge. In general, while the vehicle was crossing the curved bridge, negative reaction occurred in the inside of the girder. The final result showed that the support system located outside the girder was more advantageous than other systems, and the characteristics of load distributions differed from the others in the various conditions of support systems.