• 제목/요약/키워드: necessary support pressure

검색결과 70건 처리시간 0.023초

윈들라스 메커니즘을 적용한 트레일 워킹화 개발을 위한 생체역학적 분석 (Biomechanical Analysis for the Development of Windlass Mechanism for Trail-walking Shoe)

  • 박종진;박승범
    • 한국운동역학회지
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    • 제25권4호
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    • pp.489-498
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    • 2015
  • Objective : The purpose of this study was to analyze the effects of the windlass mechanism in trail-walking shoe prototypes that can effectively support arches. A study of these effects should help with the development of a first-rate trail-walking shoe development guide for the distribution of quality information to consumers. Methods : The subjects were ten adult males who volunteered to participate in the study. Shoes from three companies, which will be referred to as Company S (Type A), Company M (Type B), and Company P (Type C), were selected for the experiment. The subjects wore these shoes and walked at a speed of 4.2 km/h, and as they tested each shoe, the contact area, maximum pressure average, and surface force were all measured. Results : Shoe Type A showed a contact area of $148.78{\pm}4.31cm^2$, Type B showed an area of $145.74{\pm}4.1cm^2$, and Type C showed an area of $143.37{\pm}4.57cm^2$ (p<.01). Shoe Type A demonstrated a maximum average pressure of $80.80{\pm}9.92kPa$, Type B an average of $85.72{\pm}11.01kPa$, and Type C an average of $89.12{\pm}10.88bkPa$ (p<.05). Shoe Type A showed a ground reaction force of $1.13{\pm}0.06%BW$, Type B a force of $1.16{\pm}0.04%BW$, and Type C a force of $1.16{\pm}0.03%BW$ (p<.05). Conclusion : The Type A trail-walking shoe, which was designed with a wide arch from the center of the forefoot to the front of the rearfoot showed excellent performance, however, more development and analysis of the windlass mechanism for a variety of arch structures is still necessary.

비선형 베어링 요소를 이용한 탄성 추진 축계정렬에 관한 고찰 (A Study on Elastic Shaft Alignment Using Nonlinear Soaring Elements)

  • 정준모;최익흥;신상훈
    • 대한조선학회논문집
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    • 제42권3호
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    • pp.259-267
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    • 2005
  • The effects of hull flexibility on shaft alignment are growing as ship sizes are increased mainly for container carrier and LNG carrier. In order to consider hull flexibility on a propulsion shafting system, standardization of ship service conditions is necessary because hull deformation is continuously variable according to ship service conditions. How to summarize ship service conditions is suggested based on practically applicable four viewpoints : hull, engine, loading and sea status. Effects of the external forces acting on a ship propulsion shafting system are generally commented. Several design criteria regulated by classification societies are pointed at issue which seems to have Insufficient technical background. A qualitative verification is carried out to point out the invalidity of the assumption of effective supporting position. In this work, an elastic nonlinear multi-supporting bearing system is introduced as a key concept of the elastic shaft alignment. Hertz contact theory is proved to be more proper one than projected area method in calculation of the nonlinear elastic stiffness of the bearing, The squeezing and oil film pressure calculations in the long journal bearing like an after stern tube bearing are recognized as a necessary process for elastic shaft alignment design.

다중병합을 지원하는 SOA기반의 BPIL워크플로우 시스템 (SOA based BPIL workflow system to support multi integration)

  • 이기호;정창성
    • 전기전자학회논문지
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    • 제11권4호
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    • pp.283-292
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    • 2007
  • Due to the development and proliferation of internet technology, cooperation and interaction between companies have become very important. However, different heterogeneous systems have been used as information systems for companies because of various types of pressure in the business environment. Therefore, business process integration and interaction are recognized as essential elements, not optional elements. In addition, it is important to make a business process which is valuable as an intellectual property in a storable form and share. So, many business process languages for service integration and GUI type's automatic systems using the same and making business process easily have been introducing. However, to integrate previously created web service[1] workflows, or to use a web service workflow for another workflow production like an activity, that is, research to support multi integration language and system is not ongoing except for research to make and connect adapter between workflow engines.[2] Also, research for current languages and systems that integrate the BPEL[3] process into a workflow in the industrial world does not exist. This means that integration between workflows being used at companies is difficult, and becomes the biggest obstacle to service integration, which is necessary for cooperation and interaction between companies. To solve this problem, in this paper, I defined BPIL based on XML[4], which can store business processes. Also, using this, BPIL workflow system based on SOA[5] which supports multiple integration and workflow profiling was designed and prototype was embodied.

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상태기반정비에 의한 증기터빈 저널베어링의 정비주기 최적화 (Maintenance Frequency Optimization of the Steam Turbine Journal Bearings by Condition-based Maintenance)

  • 이혁순;정혁진;송우석
    • 한국압력기기공학회 논문집
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    • 제7권2호
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    • pp.7-13
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    • 2011
  • Turbine journal bearings are designed to support the weight of the rotors on a hydrodynamic oil film and to provide dynamic stability to the rotor system. The life time of journal bearings is infinite theoretically because the journal bearings are separated from the shaft journal by oil film. But poor design, assembly, operation and maintenance can cause problems to the journal bearings. The FMEA(Failure Mode and Effects Analysis) results of the journal bearings show that frequent maintenance of the journal bearings can cause failures and reduction of the bearing life. Therefore, the maintenance periods and history of the journal bearings with the bearing FMEA results are reviewed in order to establish the optimized maintenance period of the journal bearing for the nuclear power plants. Consequently it is necessary to maintain a best condition of lubrication system, reject time-based maintenance and perform the condition-based maintenance of journal bearings in order to maintain optimum condition of the journal bearing.

비노인군과 노인군 고혈압 환자의 고혈압 관리 (Hypertension Management of Non-Elderly and Elderly)

  • 김진학;정은숙;심문숙
    • 한국보건간호학회지
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    • 제31권2호
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    • pp.284-295
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    • 2017
  • Purpose: This study was conducted to compare the hypertension management between a non-elderly group and elderly group of hypertension patients in Community residents. The study also sought to generate strategies for increasing the hypertension management of residents using Community health center. Methods: Data on the general characteristics and hypertension management from 381 hypertension patients between non-elderly and elderly, living in P city, Gyeonggi Province and C city, Chungnam Province. South Korea, were collected based on a structured questionnaire, The data were analyzed using the SPSS 20.0 statistics program. Results: The use of a Community health center in the non-elderly and elderly groups showed a statistically significant difference in facility excellence and cheaper cost. Hypertension management was measured every day, The daily blood pressure and physician counseling was performed according to the changes in blood pressure. The management of hypertension medication in a community health center provided for hypertensive patients can be evaluated as an efficient service. Conclusion: The self-management ability of hypertension needs to be improved. In particular, especially, the elderly managed by the Community health center have good accessibility and a good alternative for the treatment cost. Therefore, it is necessary to provide support and measures to make hypertension management safer.

Theoretical and Experimental Considerations of Thermal Humidity Characteristics

  • Choi, Seok-Weon;Cho, Ju-Hyeong;Seo, Hee-Jun;Lee, Sang-Seol
    • International Journal of Aeronautical and Space Sciences
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    • 제3권1호
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    • pp.9-18
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    • 2002
  • Thermal humidity characteristics were considered theoretically and experimentally. A Simply well-fitted correlation of a saturated vapor pressure-temperature curve of water was introduced based on Antoine equation to make theoretical prediction of relative humidity according to temperature variation. Characteristics of dew point were also examined theoretically and its relation with temperature and humidity was evaluated. The exact mass of water vapor in a specified humidity and temperature condition was estimated to provide useful insight into the idea about how much amount of water corresponds to a specified humidity and temperature condition in a confined system. A simple but well-fitting model of dehumidification process was introduced to anticipate the trend of relative humidity level during GN2(gaseous nitrogen) purge process in a humidity chamber. Well-suitedness of this model was also verified by comparison with experimental data. The overall appearance and specification of two thermal humidity chambers were introduced which were used to perform various thermal humidity tests in order to yield useful data necessary to support validity of theoretical models.

DVD 드라이브 내에서의 유동 및 유동소음 특성에 관한 수치적 연구 (A Numerical Study on the Characteristic of Airflow and Aeroacoustic Noise in DVD Drive)

  • 유승원;이종수;민옥기;김수경
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 추계학술대회논문집
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    • pp.759-764
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    • 2000
  • The accurate prediction of aeroacoustic analysis is necessary for designers to control and reduce airflow-induced sound pressure levels in high speed rotating DVD drives. This paper focuses on the numerical prediction of airflow-induced sound in DVD drives. Computational fluid dynamics(CFD) is first conducted to evaluate flow field characteristics due to the high-speed disk rotation, and to support the acoustic analysis. The acoustic analogy based on Ffowcs Williams-Hawkings(FW-H) equation is adopted to predict aeroacoustic noise patterns. The integral solution for quadrupole volume source is included to identify the turbulence noise generated inside the DVD tray. The strength of sound pressure level with respect to rotating speed is discussed to meet upfront demand on the high fidelity product development. The present study also focuses on the noise directivity and examines how much the sound noise is sensitive to change in rotating speed. Near-field noise is strongly affected by the flow field characteristic, which is caused by the complex shape of the tray. For a mid-field, the quadrupole noise play as a counterpart of thickness noise or loading noise, so it generates different sound noise patterns compared with those in the near field.

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코로나19(COVID-19) 방역상황에서 공중보건의사의 업무 수행 현황과 지원방안 (Current Status of Work Performance and Support Plan for Public Health Doctors in the COVID-19 Quarantine)

  • 김진숙;오수현
    • 디지털융복합연구
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    • 제20권3호
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    • pp.367-376
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    • 2022
  • 본 연구의 목적은 코로나19 방역상황에 투입된 공중보건의사(PHD)의 업무 수행 현황을 조사하고, 향후 효과적인 국가 감염병 방역을 위한 공중보건의사 지원방안을 제시하는 것이다. 연구결과, 공중보건의사는 주로 검체채취, 문진 및 진료, 치료를 수행했던 것으로 나타났다. 방역에 투입된 공중보건의사의 39%는 음압시설이 없는 곳에서 근무했고, 개인 보호 장비와 복리후생 지원도 열악했던 것으로 나타났다. 또한 높은 감염위험성, 정신적 고통, 의사결정과정에서 배제, 공무원과의 갈등, 업무지침 문제, 사전교육 부족 등을 경험한 것으로 조사되었다. 따라서 향후 효과적인 감염병 관리를 위해서는 공중보건의사에게 적절한 직급 부여, 방역 관련 의사결정 과정 참여, 적절한 보상과 규정 명시, 교육과 정신건강 지원이 필요하다.

Orthodontic Acrylic Resin의 중합조건 변화가 최대하중에 미치는 영향 (The Effect of Changes in Polymerization Conditions of Orthodontic Acrylic Resin on Maximum Load)

  • 이규선
    • 대한치과기공학회지
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    • 제35권2호
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    • pp.127-136
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    • 2013
  • Purpose: In order to find out the impact of changes in polymerization conditions of orthodontic acrylic resin on maximum load. Methods: While maintaining mixing ratio 3:1 of polymer and monomer in spray-on way in the production condition of polymerization temperature $25^{\circ}C$ or $37^{\circ}C$ for 10 minutes or 30 minutes of polymerization time by pressure $3kfg/cm^2$ or $6kfg/cm^2$ in the lab maintaining $25^{\circ}C$ of room temperature, the change in maximum load rise rate was tested by producing 5 acrylic resin specimens for orthodontics per group to meet the standards of $25mm{\times}2mm{\times}2mm$ and using INSTRON with the 3rd bar 2mm in diameter and parallel support bending device of $15{\pm}0.1mm$ as test equipment showing 30.00mm/min of crosshead speed, $50{\pm}16$ N/min of load ratio in the laboratory of $24^{\circ}C$ room temperature and as a result, the following results were obtained. Results: 1. When increasing pressure from $3kfg/cm^2$ to $6kfg/cm^2$, maximum load was lowered by -4.285%. 2. When increasing polymerization time from 10 minutes to 30 minutes, maximum load rose by 3.848%. 3. When increasing polymerization temperature from $27^{\circ}C$ to $37^{\circ}C$, maximum load rose by 5.854%. Conclusion: Considering the above test results that polymerization time and polymerization temperature when polymerizing acrylic resin for orthodontics according to changes in working conditions had an impact on the rate of rise of maximum load values but the rate of rise was lowered when increasing pressure from $3kfg/cm^2$ to $6kfg/cm^2$, we came to a conclusion that high pressure more than necessary does not affect the rate of rise of maximum load.

아동의 학업스트레스와 진로성숙의 구조관계 연구 (A Study on the Structural Relationship between Children's Academic Stress and Career Maturity)

  • 김정은;김지숙
    • 문화기술의 융합
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    • 제10권1호
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    • pp.633-640
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    • 2024
  • 본 연구는 아동의 학업스트레스, 또래애착, 부모성취압력 및 진로성숙도 간의 구조관계와 직접효과, 간접효과를 분석하는데 그 목적이 있다. 본 연구 대상은 한국육아정책연구소의 아동패널 13차 연구에 참여한 초등학생 총 1,357명의 패널데이터를 활용하였다. 자료분석은 SPSS 24과 AMOS 24.0 프로그램을 사용하였다. 연구결과로 아동의 학업스트레스는 또래애착과 부적상관관계, 부모성취압력과 정적상관관계, 진로성숙도와는 부적상관관계를 나타냈다. 각 변수들은 모두 직접적인 영향관계가 있는 것으로 나타났으며 아동의 학업스트레스는 또래애착과 부모성취압력을 매개로하여 진로성숙도에 간접효과가 있었다. 결론적으로 아동의 진로성숙도 향상을 위한 학교사회복지지원이 필요할 것으로 사료된다.