• Steel and Composite Structures
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• 제28권1호
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• pp.51-61
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• 2018

A new I-girder consisted of top concrete-filled tubular flange and corrugated web has been proved to have high resistance to both global buckling of the entire girder and local buckling of the web. This study carries out theoretical analysis and experimental tests for this new I-girder to investigate the stress distribution in the flanges and in the corrugated web. Based on some reasonable assumptions, theoretical equations for calculating the normal stress in the flanges and the shear stress in the corrugated web are presented. To verify the accuracy of the presented equations, experimental tests on two specimens were carried out, and the experimental results of stress distribution were used to assess the theoretical prediction. Comparison between the two results indicates that the presented theoretical equations have enough accuracy for calculating the stress in the new I-girder, and thus they can be used reliably in the design stage.

• 한국농촌간호학회지
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• 제5권1호
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• pp.16-24
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• 2010

Nursing theory is used to explain the goals and functions of nursing and improve practical affairs by providing information and knowledge about the principles which become the foundation of nursing practical affairs. Theoretical analytical compliance with C-T-E (Conceptual-Theoretical-Empirical) structures by Fawcett (1999) whose evaluation method illustrates the relationship of conceptual models, theory, research and structure. The evaluation allows the nurse to visualize the connection, evaluate research, and reduce errors in research. Consequently present doctorate dissertations in nursing science are theoretical propriety, connection in the structure of concepts, theory, research methods, and evaluation to reduce errors in future research plans and division of theoretical development process. So the following verifies logicality, propriety, and reliability which must apply to research in various different fields.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.883-888
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• 2001

The theoretical method is developed to investigate the effects of ring stiffeners on free vibration characteristics and transient response for the ring stiffened composite cylindrical shells subjected to the impulse pressure loading. In the theoretical procedure, the Love's thin shell theory combined with the discrete stiffener theory to consider the ring stiffening effect is adopted to formulate the theoretical model. The concentric or eccentric ring stiffeners are laminated with composite and have the uniform rectangular cross section. The modal analysis technique is used to develop the analytical solutions of the transient problem. The analysis is based on an expansion of the loads, displacements in the double Fourier series that satisfy the boundary conditions. The effect of stiffener's eccentricity, number, size, and position on transient response of the shells is examined. The theoretical results are verified by comparison with FEM results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.267-272
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• 2014

In this paper, we analyze the characteristics for the driving shock resistance of the military vehicle through the bump test. Prior to the experiment, theoretical analysis was performed by using the SRS(shock response spectrum) and VRS(vibration response spectrum) analysis method. And we estimated the characteristics for the driving shock resistance of the military vehicle. Bump test was performed using the acceleration sensor and the driving test at a different speed. We evaluated the characteristics for the driving shock resistance of the military vehicle based on the result. And predicted values were compared with the theoretical analysis. In addition, we evaluated the results of the theoretical prediction of the SRS and the VRS analysis. And we evaluate the suitability of the prediction method at military vehicle shock analysis.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 봄 학술발표회 논문집
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• pp.187-194
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• 1998

• 대한기계학회논문집A
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• 제31권1호
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• pp.11-17
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• 2007

In this paper, we present a design, analysis, fabrication and performance test of the novel DoD metal-jet system for application to the high-density and high-temperature-melting materials. The theoretical analysis of the metal-jet nozzle system is derived by using electro-mechanical analogy. Based on the theoretical analysis results, we design the metal-jet print head system and fabricate the metal-jet system, which can eject the droplet of lead-free metal solder in high-temperature. In the experimental test, we set up the test apparatus for visualization of the droplet ejection and measure the ejected droplet volume and velocity. As a result, the diameter, volume and the velocity of the ejected droplet are about 65 $\mu$m $\sim$ 70 $\mu$m, 145p1 $\sim$ 180 pl and 4m/s, which shows quite good agreement with the theoretical analysis results of the 75 $\mu$m-diameter and 220 pl-volume of droplet. In comparison with the experimental result, the errors of diameter and volume are 7% $\sim$ 13% and 18 $\sim$ 34%, respectively.

• 한국음향학회지
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• 제43권4호
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• pp.391-399
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• 2024

란주반 트랜스듀서에 의해 강제 진동되는 원형 진동판으로부터 방사되는 음장의 분포를 해석하기 위하여 L. Rayleigh에 의해 도출된 진동 원판의 운동방정식을 기초로 구동 영역 및 고정 경계영역의 경계 조건을 적절히 적용하여 이론적 해석모델을 도출하였다. 도출된 해석모델을 이용하여 진동 원판의 표면에 분포하는 진동 변위를 계산하고 이로부터 방사되는 초음파에 의해 형성되는 음장을 계산한 결과, 진동 원판의 넓이에 따라 방사 특성이 크게 변함을 확인할 수 있었다. 비교를 위하여 유한요소법인 COMSOL 프로그램을 사용하여 동일한 시스템에 대한 시뮬레이션을 수행한 결과 이론 계산 결과와 좋은 일치를 보여 본 연구에서 도출한 이론적 해석모델의 유효성을 확인할 수 있었다. 본 연구에서 도출한 이론적 해석모델은 초음파 화학분야 등 관련 디바이스의 설계 및 개발에 활용될 수 있을 것으로 기대된다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.367-369
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• 2008

A theoretical model of equivalent drawbead for sheet metal forming analysis is experimentally verified in this paper. After the theoretical drawbead models improved a material description for the accurate calculation of drawbead forces are briefly introduced, they are verified by showing the good agreement of their drawbead forces with experimental measurements. Furthermore, the excellence of theoretical models is demonstrated by the comparison with those of commercial codes.

• 한국강구조학회 논문집
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• 제10권3호통권36호
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• pp.463-472
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• 1998

본 논문의 목적은 4각형네트워크 패턴을 가지는 단층래티스돔의 좌굴특성을 실험과 이론을 통하여 검토하고, 나아가 4각형 네트워크 단층돔에 대한 신뢰할 수 있는 이론해석법을 개발하기 위한 기초연구를 하는데 그 목적이 있다. 이론해석은 야마다의 연속체치환법과 유한요소법에 의한 프레임해석법으로 한다. 원주방향에 대한 불균일한 강성과 지붕재료의 강성이 돔전체 좌굴특성에 미치는 영향을 검토한다. 이론과 실험에 의한 결과는 불균일한 강성을 가지거나 또는 강성을 갖는 지붕재료를 사용하는 다양한 종류의 단층래티스돔에 대한 일반적인 이론해석법을 개발하기 위한 기초자료로 활용될 것이다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.196-200
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• 2005

단일액체추진제 하이드라진 소형로켓엔진의 이론성능해석을 위한 추진제 연소화합물의 화학평형조성 계산모델이 간략히 제시된다. 성능해석결과는 1 lbf급 추력기의 성능평가 시험결과와 암모니아 몰분율의 관점에서 비교, 분석되고, 노즐팽창비와 추진제 주입압력에 따른 화학평형 조성 및 평균분자량 등이 추가로 제시된다. 이론해석은 단일액체추진제 중 대형급 로켓엔진의 설계변수 도출의 일환으로 시도된다.