• Structural Engineering and Mechanics
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• v.66 no.3
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• pp.387-397
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• 2018

In this paper, a general closed-form solution for evaluating the dynamic behavior of a Timoshenko beam on elastic foundation under a moving harmonic line load is formulated in the frequency-wavenumber domain and in a moving coordinate system. It is found that the characteristic equation is quartic with real coefficients only, and its poles can be presented explicitly. This enables the substitution of these poles into Cauchy's residue theorem, leading to the general closed-form solution. The solution can be reduced to seven existing closed-form solutions to different sub-problems and a new closed-form solution to the subproblem of a Timoshenko beam on an elastic foundation subjected to a moving quasi-static line load. Two examples are included to verify the solution.

• Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.1-6
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• 2024

In this study, the swimming behavior of a small box jellyfish (Carybdea brevipedalia), which consists of inhaling external seawater and expelling it through its mouth to generate forward thrust, was characterized using particle image velocimetry (PIV). The flow rate and structure during the suction and discharge process were quantitatively analyzed. During swimming, there was a change in the ratio of the internal area during inhalation and expulsion. Specifically, there was a 1.10-fold difference between the maximum area after inhalation and the minimum area after discharge. The maximum distance traveled after discharge was inversely proportional to the size of the inner area, with a 2.48-fold difference in the minimum distance traveled after suction. Depending on the propulsion stage, the inner area decreased and then increased in proportion to the moving distance and speed. The moving distance of the small box jellyfish was measured for each period. The speed for each swimming stage increased and then decreased at intervals of 0.15 to 0.2 seconds, and the suction and discharge cycle period was measured at approximately 0.5 seconds. Collectively, our findings provide a methodological basis for studying the swimming behavior of small and highly active trailing jet jellyfish, as well as the biological mechanisms that determine this behavior.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.12
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• pp.843-851
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• 2011

A two-dimensional immiscible water meniscus deformation phenomena on a moving tip in a channel has been investigated by using lattice Boltzmann method involving two-phase model. We studied the behavior of a water meniscus between the tip and a solid surface. The contact angles of the tip and a solid surface considered are in the range from $10^{\circ}$ to $170^{\circ}$. The velocity of the tip used in the study are 0.01, 0.001, and 0.0001. The shapes of tip considered are rectangular and circular. The behavior of water confined between the tip and a solid surface depends on the contact angles of the tip and a solid surface, and the tip velocity. When the tip is moving, we can observe the various behaviors of shear deformation of a water meniscus. As time goes on, the behavior of a water meniscus can be classified into three different patterns which are separated from the tip or adhered to the tip or sticked to a solid surface according to the contact angles and the tip velocity.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.18-24
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• 2002

The vibrational system in this study consists of a cantilever pipe conveying fluid, the moving mass upon it, and an attached tip mass. The equation of motion is derived by using the Lagrange equation. The influences of the velocity and the velocities of fluid flow in the pipe have been studied on the dynamic behavior of a cantilever pipe using a numerical method. While the moving mass moves upon the cantilever pipe, the velocity of fluid flow and the nozzle angle increase; as a result, the tip displacement of the cantilever pipe, conveying fluid, is decreased. After the moving mass passes over the cantilever pipe, the tip displacement of the pipe is influenced by the potential energy of the cantilever pipe and the deflection of the pipe; the effect is the result of the moving mass and gravity. As the velocity of fluid flow and nozzle angle increases, the natural frequency of he system is decreased at the second mode and third mode, but it is increased at the first mode. As the moving mass increases, the natural frequency of the system is decreased at all modes.

• Journal of Families and Better Life
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• v.4 no.1
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• pp.109-125
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• 1986

In recent years, conoeptualizations of the residential crowding phenomena have developed form deterministic approaches to functionalistic ones which emphasize the interaction of environmental , social, and personal variables. The influences of each variables which are believed to mediate the crowding perception have been tested. This study examines the association of the influence of socio-demographic variables, residential setting and previous residential experience with the residential crowding. Futhermore, the residential adoptation behavior in response to the crowding phenomena is analyzed. The results of a survey are as follows; 1)The most important variables which influence residential crowding are the residential setting variables such as the floor space and the measure of persons per room. Also the household income and the family structure influence the residential crowding. No previous residential experience effects were found. 2)The residential adoptation behavior is influenced by sex, age and socio-economic status of the family. Female and the age group of 20s and 30s tend to prefer such alternatives as moving or residential alterations and additions. On the other hand, male and the age group of 40s and 50s tend to prefer staying without nay alternatives or structural family adoptation. The group of higher socio- economic status tend to show higher preference to moving and alterations, and the lower ones tend to stay or take the alternative of the structural family adoptation. Years of education and the family structure do not influence the residential adopation behavior.

• Korean journal of applied entomology
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• v.33 no.1
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• pp.33-38
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• 1994

The expenment was conducted to study the foraging behavior of Amblyseius hngisp~nosus for eggs of Tetranychus urticoe. When preys were abundant, A. longispinosus repeated a series of foraging process (feeding, after-feeding movement, restmy, and searching) The time (Mean\ulcorner SD) spent for these components were 6 83+ 1.73. 3 OOi 1.66. 93.57+ 30 19. and -0.00 min., respectively. Afterfeeding movement was chractetired as a complex one-way circular moving path with a slow speed (0.09 mm/sec) and area-restricted Escaping movement was fast (0 31 mm/sec), more straight in direction, and edge-oriented walking. Positions of prey consumption of A. longispinosus were distributed in clump. KEY WORDS Foraging behavior, nlovlng path, Arnblyseius longispinosus, Tetranychus urtlcae.

• Information Systems Review
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• v.11 no.1
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• pp.181-196
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• 2009

New domains in the analysis of the behavior of moving objects, particularly within human social settings, are generating research interest due to significant advances in the accuracy and production cost of global positioning system (GPS) devices. However, although potential applications have been described in multiple research areas, practical and viable business implementations of GPS technology remain challenging. This paper combines the potential of GPS capabilities with the analytical power of OLAP and data visualization to examine data on the movements of visitors in a zoological garden. Based on this example, the benefits and limitations of the application of GPS technology to the analysis of human spatial behavior are discussed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.3
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• pp.21-30
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• 1989

In this study, the dynamic behavior of a continuous bridge under moving load is studied considering roughness of the road surface. Vehicle model includes the spring effects of axes, and due to these effects, equations of motions for the vehicle and bridge are derived in coupled form. And then iteration method is used to solve the equations. In experimental study a bridge model is constructed considering the similarity rule in order that the model exhibits dynamic behavior similar to that of prototype. Three types of roughness such as uneven random roughness, uplift on the approach and piece-wise constant roughness are used to describe road roughness. Through the numerical analysis and experiments, the effects of surface roughness, sprung mass, and velocity on the dynamic behavior of the bridge are examined.

• Structural Engineering and Mechanics
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• v.59 no.6
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• pp.1019-1035
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• 2016

This paper proposes a new foundation model called "Dynamic foundation model" for the dynamic analysis of plates on foundation subjected to a moving oscillator. This model includes a linear elastic spring, shear layer, viscous damping and the special effects of mass density parameters of foundation during vibration. By using finite element method and the principle of dynamic balance, the governing equation of motion of the plate travelled by the oscillator is derived and solved by the Newmark's time integration procedure. The accuracy of the algorithm is verified by comparing the numerical results with the other numerical results in the literature. Also, the effects of mass and damping ratio of system components, stiffness of suspension system, velocity of moving oscillator, and dynamic foundation parameters on dynamic responses are investigated. A very important role of these factors will be shown in the dynamic behavior of the plate.

• Nuclear Engineering and Technology
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• v.49 no.8
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• pp.1654-1659
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• 2017

The boundary layer of a two-dimensional forced convective flow along a persistent moving horizontal needle in an electrically conducting magnetohydrodynamic dissipative nanofluid was numerically investigated. The energy equation was constructed with Joule heating, viscous dissipation, uneven heat source/sink, and thermal radiation effects. We analyzed the boundary layer behavior of a continuously moving needle in Blasius (moving fluid) and Sakiadis (quiescent fluid) flows. We considered Cu nanoparticles embedded in methanol. The reduced system of governing Partial differential equations (PDEs) was solved by employing the Runge-Kutta-based shooting process. Computational outcomes of the rate of heat transfer and friction factors were tabulated and discussed. Velocity and temperature descriptions were examined with the assistance of graphical illustrations. Increasing the needle size did not have a significant influence on the Blasius flow. The heat transfer rate in the Sakiadis flow was high compared with that in the Blasius flow.