• Interaction and multiscale mechanics
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• 제5권3호
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• pp.267-284
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• 2012

In most of the design offices, analysis of the frame is carried out without considering the effect of the rigidity of mat. The analysis of the superstructure without modelling the foundation properly and conversely analysing the foundation system without considering the stiffness of the superstructure may mislead the estimation of the forces. This paper examines the parameters, which affect the interaction and they are grouped into relative stiffness factors ${\kappa}_{rs}$ and ${\kappa}_{sb}$. An interaction analysis is performed for the five storeyed space frame of 3 bays ${\times}$ 5 bays, using ANSYS finite element code. The soil was treated as an isotropic, homogenous and elastic half space medium and the following conclusions were drawn from the analyses. The differential settlement is reduced due to interaction and the performance of the mat depends on ${\kappa}_{sb}$ values. The moments $M_x$ and $M_y$ in the corner column at all the storey levels are higher in the case of the interaction analysis than in the conventional analysis. The axial forces in the peripheral columns increased and to that extent, the inner column axial loads are reduced. In the beam, more variation is seen in the support moments than in the span moments.

• 한국해양공학회지
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• 제30권3호
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• pp.151-160
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• 2016

The diffraction and radiation of linear waves by an array of truncated floating multiple buoys are solved using the interaction theory based on a matched eigenfunction expansion method (MEEM). The interaction processes between multiple buoys are very complex and numerous, because the scattered and radiated waves from each buoy affect the others in the array. Our primary aim is therefore to construct the rigorous wave exciting forces and hydrodynamic forces to deal with the problem of multiple interactions. This present method is applied to a square array of four buoys with two incidence angles, and the results are given for the wave excitation forces on each buoy, heave RAO for each buoy heaving independently, and wave elevations around the buoys and wave run-up. The analytical solutions are in good agreement with the numerical solutions obtained from commercial code (WAMIT).

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.641-644
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• 2005

The study on the interaction forces of some biological materials is important to understanding biological phenomena and their application to practical purpose. This paper introduces a measuring technique for biological adhesive forces using the AFM(Atomic Force Microscope). Since no standardized thesis on adhesive forces exist, the adhesive forces is defined as adhesive forces against a hardened surface of biological materials. To grant the results are meaningful, which is based on the understanding the surface characteristics of biological materials using the AFM, a nominal value of average adhesive force per unit area should be measured. Therefore the modified AFM probe with small micro glass bead was proposed so that it can guarantee the required contact area for measuring the average adhesive forces. A pyrex glass substrate with circular patterns, which was fabricated by micromachining technique, is introduced in order to controll the contact area. The two types of mussel adhesive proteins, Celltak and recombinant-MGFP5, were tested by the proposed measuring method. The test results show that the adhesive force of the mussel adhesive proteins can be reliably measured by use of this method.

• 전자공학회논문지A
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• 제33A권7호
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• pp.15-22
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• 1996

In the soliton transmission system for a long-length and high bit rate data transmission systme using the nonlinear/dispersive optical fibers, the improtant problem is the loss characteristics and is the limited transmission rate by interaction forces. In this paper, It is explained the reasons of moved time position for the soliton peak value due to interaction force sof adjacent solitons. And for the analysis of interaction force affection level in the losslessmedia, we define the percent parameter of error rate due to the interaction forces and propose the optimum time distance of adjacent solitons by peak value tracking methods. With the results, initial percent of error is approximately 50% when itme difference between adjacent solitons is 5 times of funddametnal soliton pulse width. And it is confirmed that maximum transmission length of th esolitons is approximately 38 times of fundamental soliton period, which the maximum allowable percoent of error is 50%.

• Structural Engineering and Mechanics
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• 제13권4호
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• pp.455-464
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• 2002

There is a growing demand to assess the remaining strength and endurance of existing composite steel and concrete bridge beams due to the aging infrastructure, increases in permissible vehicle weights and increases in their frequencies. As codes are generally dedicated to the design of new structures, new procedures are required to aid in the assessment of existing bridges to ensure that they are utilised to the full. In this paper, simple expressions are presented to perform partial-interaction analyses directly from full-interaction analyses, so that the beneficial effect of partial-interaction on the shear forces on the shear connectors can be utilised in assessment to extend the fatigue life of simply supported bridge beams and to determine the effect of remedial work if necessary. Use of the assessment technique is described by way of an illustrative example.

• 동력기계공학회지
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• 제14권5호
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• pp.48-55
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• 2010

When a large ship is advancing in waves, ship undergoes the hydroelastic response, which has influences on structural stability and the fatigue destruction etc. of the ship. Therefore, to predict accurate hydroelastic response, it is necessary to analyze hydroelastic response including fluid-structure interaction. In this research, a ship is divided into many hull elements to calculate the fluid forces and wave exciting forces on each elements using three-dimensional source distribution method. The calculated fluid forces and wave exciting forces are assigned to nodes of hull elements. The neighbor nodes are connected with elastic beam elements. We analyzed hydroelastic responses, and those are formulated by using finite element method. Particularly, to estimate the influence of forward speed on the hydroelastic responses, we use two different methods : Full Hull Rotation Method(FHRM) and Sectional Hull Rotation Method(SHRM).

• 한국항해항만학회지
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• 제31권7호
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• pp.569-578
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• 2007

The primary objective of this study is to present a modified method of hydroelastic analysis and application of it to the VLFS with submerged plate. The modal analysis method is applied to the VLFS with the submerged plate using the modified hydrodynamic coefficients. Namely, the wave exciting forces are modified by the transmission wave coefficients, while the interaction factor is used for the modification of radiation forces. To validate the proposed method, comparisons between the numerical calculations and experimental data have been carried out for the deflections of VLFS, and it shows good agreement between the calculation and experiment. The results presented in this study demonstrate that the elastic response of the VLFS is strongly affected by the hydrodynamic interaction induced by the submerged plate. As a result, we can confirm that the submerged plate is useful for reducing the hydroelastic deflection of VLFS, and the proposed method is valuable for predicting the elastic response of VLFS with attached the submerged plate.

• Structural Engineering and Mechanics
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• 제41권6호
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• pp.711-734
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• 2012

The foundation of a tall building frame resting on settable soil mass undergoes differential settlements which alter the forces in the structural members significantly. For tall buildings it is essential to consider seismic forces in analysis. The building frame, foundation and soil mass are considered to act as single integral compatible structural unit. The stress-strain characteristics of the supporting soil play a vital role in the interaction analysis. The resulting differential settlements of the soil mass are responsible for the redistribution of forces in the superstructure. In the present work, the nonlinear interaction analysis of a two-bay ten-storey plane building frame- layered soil system under seismic loading has been carried out using the coupled finite-infinite elements. The frame has been considered to act in linear elastic manner while the soil mass to act as nonlinear elastic manner. The subsoil in reality exists in layered formation and consists of various soil layers having different properties. Each individual soil layer in reality can be considered to behave in nonlinear manner. The nonlinear layered system as a whole will undergo differential settlements. Thus, it becomes essential to study the structural behaviour of a structure resting on such nonlinear composite layered soil system. The nonlinear constitutive hyperbolic soil model available in the literature is adopted to model the nonlinear behaviour of the soil mass. The structural behaviour of the interaction system is investigated as the shear forces and bending moments in superstructure get significantly altered due to differential settlements of the soil mass.

• 한국시뮬레이션학회논문지
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• 제26권3호
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• pp.47-54
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• 2017

본 연구에서는 선박조종시뮬레이터를 이용하여 선박의 크기에 따른 두 선박의 간섭력의 운동특성을 분석하였다. 파나막스급 컨테이너선이 자선보다 크기가 작은 계류선을 근접통항하는 경우에 계류선에서 간섭력의 피크점과 운동패턴의 변화가 뚜렷하게 나타났다. 이땐 선박의 정횡 상태 전후에서 전후력과 회두모멘트가 반대방향으로 바뀌므로 계류선의 움직임에 각별한 주의가 요구된다. 반대로 파나막스급 컨테이너선이 자선보다 큰 계류선을 통과하는 경우에는 근접상황이 발생하는 초기에 통과선에서 간섭력의 피크점이 나타났고, 통과선에는 정횡 이후 약 1L(통과선의 전장)의 구간동안 지속적으로 흡인력이 발생했다. 또한, 통과선과 계류선의 선체간의 수평거리가 2B(통과선의 폭)이하로 줄어들면, 통과선의 초기에 발생하는 간섭력이 급격히 증대된다.

• Molecules and Cells
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• 제45권1호
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• pp.26-32
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• 2022

Living cells generate, sense, and respond to mechanical forces through their interaction with neighboring cells or extracellular matrix, thereby regulating diverse cellular processes such as growth, motility, differentiation, and immune responses. Dysregulation of mechanosensitive signaling pathways is found associated with the development and progression of various diseases such as cancer. Yet, little is known about the mechanisms behind mechano-regulation, largely due to the limited availability of tools to study it at the molecular level. The recent development of molecular tension probes allows measurement of cellular forces exerted by single ligand-receptor interaction, which has helped in revealing the hitherto unknown mechanistic details of various mechanosensitive processes in living cells. Here, we provide an introductory overview of two methods based on molecular tension probes, tension gauge tether (TGT), and molecular tension fluorescence microscopy (MTFM). TGT utilizes the irreversible rupture of double-stranded DNA tether upon application of force in the piconewton (pN) range, whereas MTFM utilizes the reversible extension of molecular springs such as polymer or single-stranded DNA hairpin under applied pN forces. Specifically, the underlying principle of how molecular tension probes measure cell-generated mechanical forces and their applications to mechanosensitive biological processes are described.