• 드라이브 ㆍ 컨트롤
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• 제10권3호
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• pp.27-33
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• 2013

Solenoid valve has used in various industrial field extensively. A solenoid valve has different size, shape and method of operation accordantly to industrial field. Many researchers study on kinds of solenoid valve such as flow rate, dynamic, magnetic field, valve shape and operating method. But the flow rate characteristic and dynamic response time performance on the diaphragm valve are not studied. This paper describes the flow rate characteristic and dynamic response time performance on the diaphragm valve. At first, the diaphragm valve is simulated in AMESim simulation tool. AMESim model found that an effect of valve performance depends on parameter. The parameter is the diaphragm orifice area. And the performance test bench confirms the effect in this parameter. Finally, it finds out the flow rate characteristic and dynamic response time performance on the diaphragm valve.

• 한국재료학회지
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• 제20권12호
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• pp.640-644
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• 2010

Information technology devices, such as cellular phones, MP3s and so on, due to restrictions of space, require thin and small micro-speakers to generate sound. The reduction of the size of micro-speakers has resulted in the decrease of sound quality, due to such factors as frequency range and sound pressure level. In this study, the acoustical properties of oval microspeakers has been studied as a function of pattern shape on the diaphragm. The other conditions of micro-speakers, except for the pattern, was not changed. When the pattern is present on the diaphragm and the shape of pattern was a whirlwind, the resonance frequency was reduced due to the decrease of tensile strength of diaphragm. The patterns presented in the semi-minor axis of diaphragm did not effect a change of resonance frequency. However, increasing the number of patterns in the semimajor axis of diaphragm became a reason for the decrease of resonance frequency on edge side. When the depth of pattern on edge side was increased, the resonance frequency was decreased due to reduction of geometrical stiffness. If the height of edge and dome were increased, the resonance frequency and geometrical stiffness rapidly increased. After reaching the maximum values, they began to decrease with the continuous increase of height.

• Steel and Composite Structures
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• 제20권3호
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• pp.487-500
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• 2016

In order to investigate the flexural bearing capacity of panel zone of diaphragm-through joint between concrete filled square steel tubular column and steel beam, four specimens were tested under static tension loads to study the mechanical properties and bearing capacity of diaphragm-through joints with a failure mode of panel zone. Finite element models of these specimens were developed to simulate the test and compare the predicted failure modes, load-displacement curves and bearing capacities with the experimentally observed. It was found that the tensile load from the steel beam flange is mainly shared by the square steel tube and the diaphragm. The diaphragm plastic zone appears along the cross-section lines enclosed by the square steel tube and the influence of steel beam web on the plastic zone of the steel tube is significant and cannot be neglected. Computational models of yield lines on square steel tube and diaphragm are established based on the distribution pattern of the plastic zone, and an analytical method for the evaluation of the bearing capacity of the joint is proposed. The theoretical results and the experimental data are compared and found in good agreement.

• Steel and Composite Structures
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• 제7권4호
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• pp.303-320
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• 2007

The objective of this study is to clarify the structural features of members consisting of connection, as a series of the previous study on the CFT column-to-beam tensile connection with combined cross diaphragm. This connection has the merits that the stress is distributed evenly on the beam flange and the diaphragm and the stress concentration is reduced, by improving the stress transfer route and restraining abrupt deformation of diaphragm. The finite element analysis was performed to find out the stress transfer through sleeve which is an important member of the connection with combined cross diaphragm. The length and thickness of sleeve were used as variables for the analysis. As the analysis results, the length and thickness of sleeve didn't influence on the capacity of the connection and played a role of a medium to transfer the stress from the diaphragm to the filled concrete. It is proposed that the appropriate length of sleeve be the same value as the diameter of sleeve and the appropriate ratio of sleeve diameter to sleeve thickness be 20. Two equations for evaluation of the load-carrying capacity of the connection were also proposed through the modification of the evaluation equation suggested in the previous study.

• 한국가스학회지
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• 제21권3호
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• pp.33-38
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• 2017

국내 CNG Bi-fuel Kit를 개조한 차량들은 대부분 Diaphragm 감압방식을 적용한 기계식 레귤레이터를 장착하여 운행 중에 있다. 하지만 Diaphragm의 재질 특성 및 기계식 압력제어 방식의 특성 상 다양한 문제점들이 발생되고 있으며, 이를 개선하기 위한 연구들이 진행되고 있다. 본 연구에서는 CNG 차량용 레귤레이터의 압력제어방식에 따른 성능특성 확인 및 비교 분석 진행을 통해 개선방안을 도출하고자 하였다. 실험 결과에 따르면 Diaphragm을 적용한 감압방식이 Piston을 적용한 방식보다 일반적인 성능에서 유리하였으나 주변 온도환경 변화에 따른 변동 폭이 큰 것을 확인하였다. 또한 전자식 압력제어를 통해 레귤레이터의 일반적인 성능을 향상시킬 수 있음을 확인하였다.

• 한국강구조학회 논문집
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• 제25권2호
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• pp.187-196
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• 2013

CFT구조의 기둥-보 접합부는 강관의 국부좌굴을 방지하기위해 다이아프램이 필요하다. 외측다이아프램 형식은 관통다이아프램 형식보다 콘크리트의 충전성이 좋으나 시공성과 건축설비와 공조하는 측면에서 불편함이 있다. CFT구조 접합부의 상부 다이아프램은 외측다이아프램 형식으로 하고 하부 다이아프램은 관통다이아프램 형식으로 하였다. 이것은 건축물에서 바닥슬래브가 있으므로 상부 다이아프램은 바닥슬래브와 일체가 되고 하부 다이아프램으로 관통다이아프램을 적용하여 건축설비와의 마찰을 피하고자 한 것이다. 결과적으로 충전성을 개선시킨 CFT구조의 구조성능은 상, 하부 모두 관통다이아프램을 적용한 구조와 비교하면 동일하다는 것을 알 수 있다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제5권1호
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• pp.17-23
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• 2005

This paper describes the simulation of a micromachined dome-shaped-diaphragm acoustic transducer built on a $1.5{\mu}m$ thick silicon nitride diaphragm ($2,000{\mu}m$ in radius, with a circular clamped boundary on a silicon substrate) with electrodes and piezoelectric ZnO film in a silicon substrate. Finite element analysis with ANSYS 5.6 has been performed to analyze the static and dynamic behaviors of the transducer under both pressure and voltage loadings.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1996년도 제24회 추계학술대회
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• pp.195-201
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• 1996

The dynamic characteristics of externally pressurized journal bearing have been studied theoretically. The Reynolds' equation has been solved by FDM, and the dynamic coefficients have been calculated by using perturbation method. The bearing is compensated by orifice or double-pad diaphragm control valve. The effects of diaphragm initial gap and stiffness are considered. As the results of analysis, it is shown that a control valve has better performance than orifice.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.151-152
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• 2022

When reinforcing an existing building with the Concrete Filled Tube(CFT) structure, it is impossible to form a diaphragm inside with the existing method. Therefore, in this study, a construction method was proposed so that the internal diaphragm could be welded on four sides by using a slot to transmit force.

• Journal of Yeungnam Medical Science
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• 제14권1호
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• pp.46-52
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• 1997

생리적 특성이 독특한 횡경막의 운동시 당원이 용양상과 운동 후 경구 투여한 당이 당원으로 재축적되는 과정을 적색비복근과 비교하여 횡경막의 생리적 특성의 일단을 규명하고자 시도한 연구 결과를 요약하면 다음과 같다. 대조군에서 횡경막의 당원농도는 적색비복근보다 높은 경향을 보였으며, 운동군에서 운동부하 첫 1시간에 횡격막의 당원농도는 약 1/2로 감소하였고 그 후 지속되는 1시간동안에는 별 차이를 보이지 않았으며 적색비복근의 당원농도와는 유의한 차이를 발견할 수 없었다. 그러나 당원 감소속도를 분석한 결과 횡격막이 적색비복근보다 빠른 경향을 보였다. 횡격막의 당원 재축적량 및 재축적속도를 분석한 결과 운동부하군에서 최대축적량은 적색비복근보다 낮았으며 재축적속도는 대조군에서는 양근에서 비슷하였으나 운동부하군에서는 적색비복근이 빨랐다. 당투여에 의한 골격근의 당원축적은 주로 근원섬유사이에 분포함을 전자현미경 관찰을 통해서 알 수 있었다. 이상의 결과로 미루어보아 횡격막은 운동부하시 당원의 소모는 비교적 빠른 경향이었으나 당투여에 의한 재축적은 느린 것을 알 수 있었다.