• Journal of the Society of Naval Architects of Korea
• /
• v.51 no.6
• /
• 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.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.17 no.1
• /
• pp.78-89
• /
• 1993

A new theory based on the modified momentum and energy conservation has been proposed in order to overcome the drawbacks included in previous theories which are used for the determination of dynamic yield stresses and the investigation of dynamic behavior of metals. Then the improvements suggested by the new theory have been manifested through the analysis of the error included in the measurement of deformed length and through the comparison between the new theory, existing theories, and experimental results performed by previous workers. Meanwhile rod impact test has been performed which uses a compressed- air system for the acceleration of flat-ended cylindrical free-cutting brass rods. From the geomtrical measurements of deformed length, the dynamic yield stress of free-cutting brass has determined.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2008.10b
• /
• 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.

• Journal of Korean Society of Rural Planning
• /
• v.26 no.3
• /
• 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
• /
• v.8 no.9
• /
• 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".

• Proceedings of the Korea Concrete Institute Conference
• /
• 2006.11a
• /
• 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.

• Journal of the Society of Disaster Information
• /
• v.12 no.1
• /
• pp.62-68
• /
• 2016

In this study, the impact problems are brought up and the formulation by isoparametric element is attempted for the purpose of analyzing the response characteristics of laminated plate receiving impact load based on the first-order shear deformation theory expanded from the Mindlin plate theory. The result of static analysis and dynamic analysis is drawn through the numerical analysis rectangular and circular plates of antisymmetric Angle-Ply laminated plate using the finite element method and the analysis on each displacement is compared.

• 제어로봇시스템학회:학술대회논문집
• /
• 1999.10a
• /
• 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.

• Journal of KSNVE
• /
• v.9 no.3
• /
• 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.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.15 no.3
• /
• 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.