• 대한조선학회논문집
• /
• 제51권6호
• /
• pp.503-509
• /
• 2014

This paper describes the time-domain numerical method for prediction of slamming loads on a ship in waves using the strip theory. The slamming loads was calculated considering the relative vertical velocity between the instantaneous ship motion and wave elevation. For applying the slamming force on a ship section, the momentum slamming theory and the empirical formula-based bottom slamming force were used corresponding to the vertical location of wetted body surface. Using the developed method, the vertical bending moments, relative vertical velocities, and impact forces of S175 containership were compared in the time series for various section locations and wave conditions.

• 대한기계학회논문집
• /
• 제17권1호
• /
• pp.78-89
• /
• 1993

본 연구에서는 Gillis 이론의 이와같은 단점을 보완하기 위하여 Gillis에 의 하여 제시된 수정운동량 보존법칙과 Hawkyard에 의하여 제시된 에너지보존법칙을 일반 화한 수정에너지보존법칙을 동시에 고려하여 재료의 동적항복응력을 결정할 수 있으며, 봉충격시험편의 충돌완료 후의 변형형상간의 관계를 고려할 수 있는 이론을 제시하였 다. 또한 기존의 실험결과로부터 제시된 이론의 타당성을 분석하였으며, 시험편의 변형형상의 측정오차가 동적항복응력의 결정에 미치는 영향을 분석하였다. 한편 압 축공기를 이용한 시험편 가속정치에 의하여 봉충격시험을 수행하여 괘삭황동(free -cutting brass)의 고변형률속도하에서의 변형특성과 동적항복응력을 결정하였다.

• 한국산업정보학회:학술대회논문집
• /
• 한국산업정보학회 2008년도 추계 공동 국제학술대회
• /
• pp.249-254
• /
• 2008

Since Lau and Murnighan first introduced the concept of faultlines in 1998, there are many extended studies related to faultlines theory. It is obvious that faultlines theory adds valuable explanations in addition to what numerous previous demographic studies have explored. However, previous research has not been able to fully integrate the characteristics embedded in the workplace environments, and the influence of faultlines in IT industries has yet to be explored. So it is not reasonable and convincing to extend the findings from previous faultlines research to other industries in the global world. In this study, IT related influence is given considerable weight into traditional faultlines theory and the impact of IT-based faultlines is revealed. Our study indicates that IT-based faultlines have negative impact on task conflict, process conflict and relationship conflict, and also have negative impact on individual outcomes such as individual performance and satisfaction. The influence of IT-based faultlines on people s intend to remain in the current organization is found to be insignificant. Our empirical study reconfirmed that faultlines are important indicator in group works and also that faultlines are intimately related to various conflicts and individual outcomes. We hope our research findings would be beneficial to the organizations concerned with effective and efficient group work.

• 농촌계획
• /
• 제26권3호
• /
• pp.115-126
• /
• 2020

This study designed an extended technology acceptance model incorporating and combining TPB, TAM, UTAUT, and IDT, which are known to be useful in explaining technology acceptance intention, to analyze antecedents affecting smart farm acceptance intention from the perspective of policy handlers. In the model of this study, nine independent variables were set, including subjective norm, perceived behavioral control, attitude, perceived usefulness, performance expectation, effort expectation, social impact, promotion condition, and fitness. The effect of these variables on farm acceptance intention was analyzed. The study found that four factors, including perceived behavioral control, perceived usefulness, social impact, and fitness, had positive effects on the acceptance intention of smart farms. Of these, perceived usefulness had the highest impact. In conclusion, all the TPB, TAM, UTAUT, and IDT applied to the research hypothesis to explain the smart farm acceptance intention included on or more variables with significant effects. In other words, these theories were evaluated as useful to explain the acceptance intention of smart farms.

• The Journal of Asian Finance, Economics and Business
• /
• 제8권9호
• /
• pp.341-349
• /
• 2021

This study is conducted to fill the research gap in proposing and testing the relationship between "Attitudes about the overall image of the destination", "Subjective norms" and "Perceived behavioral control". Simultaneously, we examine the relationship between these variables and tourists' "intent to choose a destination.". While most previous studies only deal with the relationship between destination image and intended behavior of tourists, this study uses the theory of planned behavior (Ajzen, 1991) to explain the intended behavior of tourists. In addition, the Theory of Destination Image (Echtner & Ritchie, 1991) is used to explain the factor "attitudes about the overall image of the destination", contribute to supplementing and perfecting the Theory of Planned Behavior. This study uses a Structural Equation Modeling (SEM) to analyze a sample of 993 observations, the subjects of which are international tourists to Vietnam, to test the relationship between second-order constructs. The test results show that "Subjective norms" and "Perceived behavioral control" have an impact on "Attitudes about the overall image of the destination". Moreover, all these three factors have an impact on "Intent to choose destination", in which the factor "Perceived behavioral control" has the greatest impact on "intention to choose destination".

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
• /
• pp.857-860
• /
• 2006

In the present study, the method and procedure for analysis of impact damage behavior for concrete under penetration and perforation of projectile is investigated. Conservation law, equation of motion, initial and boundary conditions, and FEM formulation are introduced and derived respectively. Specially, the constitutive equation which rate-dependent damage combined with rate-dependent plasticity within the appropriate framework of theory of thermodynamics is examined. This paper aimed at the review with respect to impact damage models for concrete to develop that model. This paper is a basis research for the development of impact damage model for concrete.

• 한국재난정보학회 논문집
• /
• 제12권1호
• /
• pp.62-68
• /
• 2016

본 연구에서는 충격 문제를 거론하며 Mindlin 판 이론을 확장한 1차 전단 변형 이론에 근거하여 충격 하중을 받는 적층판의 응답 특성의 해석을 목적으로 아이소파라메트릭요소에 의한 정식화를 시도한다. 유한요소법을 이용하여 역대칭 Angle-Ply 적층판의 사각판과 원형판의 수치해석을 통해 정적해석과 동적해석의 결과를 도출하여 각 변위에 대한 분석결과를 비교한다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1999년도 제14차 학술회의논문집
• /
• pp.274-277
• /
• 1999

This paper is concerned with estimating the mass of a loose part in the steam generator of a nuclear power plant. Although there is the basic principle known as “Hertz Theory”for estimating mass and energy of a spherical part impacted on an infinite flat plate, the theory is not directly applicable because real plants do not comply with the underlying ideal assumptions. (Say, the steam generator is of a cylindrical and hemisphere shape.) In this work, a practical method is developed based on the basic theory and considering amplitude and energy attenuation effects. Actually, the impact waves propagating along the plate to the sensor locations become significantly different in shape and frequency spectrum from the original waveform due to the plate and surrounding conditions, distance attenuation and damping loss. To show the validity of the present mass estimation algorithm, it has been applied to the mock-up impact test data and also to real plant data. The results show better performance comparing to the conventional Hertz schemes.

• 소음진동
• /
• 제9권3호
• /
• pp.485-492
• /
• 1999

The effects of boundary conditions on vibration characteristics for the ring stiffered composite cylindrical shells are investigated by theoretical and experimental method. In the theoretical procedure, the Love's thin shell theory combined with the discrete stiffener theory to consider the ring stiffening effect are adopted to derive the frequency equation. In experiment, the impact exciting method is used to obtain the vibraton results. Five different boundary conditions: clamped-clamped, simply supported-simply supported, free-free, clamped-free, clamped-simply supported are considered in this study.

• 대한기계학회논문집
• /
• 제15권3호
• /
• pp.735-750
• /
• 1991

본 연구에서는 적층 복합판의 충격 해석을 위하여 Reddy의 고차 전단 변형 이 론에 기초를 두고, 정적 압입 실험에 의한 접촉 법칙을 고려한 동적 유한 요소 해석 (dynamic finite element analysis)을 행하여 충격 실험에 의한 결과와 1차 전단변형 이론에 의한 해와 비교 검토하므로서, 그 유용성과 우수성을 입증하고, 적층 복합재의 충격 응력 및 응력파 전파 특성에 대하여 연구하고자 한다.