• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.4
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• pp.55-60
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• 2010

Rodents can recognize objects by using their whiskers. Not only rodents but also mammals use their whiskers to recognize objects. However, rodents can discriminate surface roughness in micrometer resolution throughout their whisker sensing. Rats can distinguish an target object's shape, roughness and surface pattern by moving their whisker back and forth freely. Mechanoreceptors surrounding the whisker in their follicle measure deflection and vibration of the whisker. In this paper, we designed biomimetic whiskers modeling rodent whiskers and showed the characteristic properties to extract the information of surface roughness.

• Computers and Concrete
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• v.10 no.4
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• pp.419-434
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• 2012

This paper presents a finite element (FE) model for predicting the nonlinear response and behavior of a reinforced concrete T-beam deficient in shear under cyclic loading. Cracking loads, failure loads, response hysteresis envelopes and crack patterns were used as bench mark for comparison between experimental and FE results. A parametric study was carried out to predict the optimum combination of the open and close crack shear transfer coefficients (${\beta}_t$ and ${\beta}_c$) of the constitutive material model for concrete. It is concluded that when both shear transfer coefficients are equal to 0.2 the FE results gave the best correlation with the experimental results. The results were also verified on a rectangular shear deficient beam (R-beam) tested under cyclic loading and it is concluded that the variation of section geometry has no effect on the optimum choice of the values of shear transfer coefficients of 0.2. In addition, a parametric study based on the variation of concrete compressive strength, was carried out on the T-beam and it is observed that the variation of concrete compressive strength has little effect on the deflection. Further conclusions and observations were also drawn.

• Journal of KIBIM
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• v.6 no.3
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• pp.42-48
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• 2016

Structural members are designed to maintain the load-carrying capacity as well as structural strength, and the structural serviceability such as the deflection, cracks, and vibration to give the occupants uncomfortable environment should be checked. Recently, the importance of the vibration has been issued since the Techno Mart accident due to vibration resonance. This study provides a passive vibration control system using the repulsion force of magnets to reduce dynamic vibrations. The systems is devised by importing the constraint condition by a hinge to operate magnets installed at two adjacent locations. The effectiveness of the proposed system is investigated by the vibration control test of a steel beam with and without the control system. It is illustrated in the test that the system is activated by the control forces executed by the magnets and can be utilized in reducing the dynamic responses. The system can be applied to pedestrian bridge and traffic bridge. The applicability is expected in the future by optimizing the factors to affect the dynamic responses like the intensity, mass, locations of magnets.

• Journal of Drive and Control
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• v.18 no.2
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• pp.38-45
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• 2021

In recent years, the demand for an onboard scale system which can directly monitor load distribution and overload of vehicles has increased. Depending on the suspension type of the vehicle, the onboard scale system could use different types of sensors, such as, angle sensors, pressure sensors, load cells, etc. In the case of a vehicle equipped with leaf spring suspension system, the load of the vehicle is measured by using the deflection or displacement of the leaf spring. Leaf springs have hysteresis characteristics that vary in displacement depending on the load state. These characteristics cause load measurement errors when moving or removing cargoes. Therefore, this study aimed at developing an onboard scale device for cargo vehicles equipped with leaf springs. A sectional modeling method which can reduce measurement errors caused by hysteresis characteristics was also proposed.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.537-544
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• 2003

Mass movement of anchored walls is defined and its characteristics were discussed. A beam on elasto-plastic foundation modeling of soldier pile and woodlagging tieback walls or anchored walls was developed and used in practice. However, the behavior of an anchored wall can not be predicted well, if the locations of anchor bonded zone are near the wall. Mass movement is defined as the movement of anchor bonded zone due to the excavation without the change in the anchor load. Case histories of anchored walls were analyzed and the normalized mass movement chart were developed. This mass movement chart can provide the idea how to locate anchors to minimize the deflection of the wall. The further the anchor bonded zone is located from the wall, the less the movement of the wall due to excavation occurs.

• International Journal of Concrete Structures and Materials
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• v.6 no.2
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• pp.111-121
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• 2012

The research presented in this paper analytically examines the fire performance of flat plate buildings. The modeling parameters for the mechanical and thermal properties of materials are calibrated from relevant test data to minimize the uncertainties involved in analysis. The calibrated models are then adopted to perform a nonlinear finite element simulation on a flat plate building subjected to fire. The analysis examines the characteristics of slab deflection, in-plane deformation, membrane force, bending moment redistribution, and slab rotational deformation near the supporting columns. The numerical simulation enables the understanding of structural performance of flat plate under elevated temperature and, more importantly, identifies the high risk of punching failure at slab-column connections that may trigger large-scale failure in flat plate structures.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.302-306
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• 1993

In this study, a new model for flexible disk grinding process will be proposed. A grinding mechanism with a grinding disk attached to the rubber platen has been introduced. Since the spinning axis is fixed and only the disk is deflected with respect to this axis, earlier model is not adequate to represent this proces. A new dynamic process model includes an assumption that the disk is deflected locally around the middle of its radial span between the spinning axis and the disk tip instead of several continuous deflection points along the radial span of the disk. Detailed kinematic analysis is proposed as for the removed portion during the process. Cutting force comonent and depth of cut profile trend is compared with the measured result.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.73-76
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• 2007

Electro-Active paper (EAPap) is a new smart material that has a potential to be used in biomimetic actuator and sensor. It is made by cellulose that is abundant material in nature. EAPap is fascinating with its biodegradability, lightweight, large displacement, high mechanical strength and low actuation voltage. Actuating mechanism of EAPap is known to be the combined effects of ion migration and piezoelectricity. However, the electromechanical actuation mechanisms are not yet to be established. This paper presents the modeling of the actuation behavior of water infused cellulose samples and their composite dielectric constants calculated by Maxwell-Wagner theory. Electro-mechanical forces were calculated using Maxwell stress tensor method. Bending deflection was evaluated from simple beam model and compared with experimental observation, which result good correlation with each other.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.495-499
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• 2014

In this study, the finite element modeling for the signal cable and pneumatic hose of the industrial robot is developed. The modulus of elasticity of signal cable and pneumatic hose is predicted by deflection test. Finite element model for the signal cable and pneumatic hose is developed by using the modulus of elasticity obtained from the tests. The developed finite element model is estimated through the vibration analysis. This study shows that the developed finite element model can be effectively utilized in the dynamic analysis.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.11
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• pp.1006-1011
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• 2004

Carbon nanotubes have outstanding properties which make them useful for a number of high-technology applications. Especially, single-walled carbon nanotube (SWNT), working under physical conditions (in aqueous solution) and converting electrical energy into mechanical energy directly, can be a good substitute for artificial muscle. The carbon nanotube structure simulated in this paper is an isotropic cantilever type with an adhesive tape which is sandwiched between two SWNTs. For predicting the geometrical and physical parameters such as deflection, slope, bending moment and induced force with various applied voltages, the analytical model for a 3 layer bimorph nanotube actuator is developed by applying Euler-Bernoulli beam theory. The governing equation and boundary conditions are derived from energy Principles. Also, the brief history of carbon nonotube is overviewed and its properties are compared with other functional materials. Moreover, an electro-mechanical coupling coefficient of the carbon nanotube actuator is discussed to identify the electro-mechanical energy efficiency.