• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.385-388
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• 2000

Electromagnet ic wave falling on solid surface acts on the medium with a force. This force brings about a redistribution of surface charges and the surface potential is varied. By measuring this potential variations, the surface electrical properties on conductors, semicionductors and dielectrics can be tested. In this paper, two dimensional photocharge voltage on the $LiNbO_3$ wafer induced by He-Ne laser beam, the temperature characteristics and the capacitive coupling test structure for the photocharge voltage measurement for the dielectrical materials are shown.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.304-307
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• 2003

Usually, the thrust of a Linear Pulse Motor(LPM) is calculated by magnetic equivalent circuit modelling method. Analytical thrust deviation exists to calculating magnetic flux density by using Permeance Modelling Method, Finite Element Method, and Velocity Electric Motive Force method. For calculating accuracy thrust by using these every method, tire thrust is calculated and compared by Lorentz Force method, Magnetic coenergy Method, and Maxwell correspondence forte Method. And that becomes Important factor at the comparison of each capacity and parameter of motor. So this study wants to compare and analyze measurement data and calculating data of the static thrust of LPM. and then we can get more accuracy method, calculating the static thrust of LPM.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.113-113
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• 2003

Four main factors, cling force, wicking force, water retention and water transport, affecting the clinginess of the sportswear fabric have been identified and measured by combining a new equipment and a statistical analysis. A classification model based on those factors has been developed in order to evaluate and standardize fabric wear comforts during heavy physical acting. Ten sportswear fabrics assumed different in their wear characteristics have been employed to investigate the relationship between the measurements and actual performance. It has been shown that the subjective evaluation ratings were well agreed with the measurement.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.265-268
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• 2005

A new method for measurement of the pore size in a nanohoneycomb structure using atomic force microscopy (AFM) was proposed. Porous type anodic aluminum oxide (AAO) was fabricated as a nanohoneycomb structure to measure the pore size. For measuring pore sizes from AFM images, a criterion was set in porous type AAO. The pore sizes from AFM images were compared with those from SEM images, and the results showed good agreement. The relationship between the pore size and widening time was found to be linear in the range of this study. It was understood as the synchronized effects of the impurity gradient in outer oxide of AAO, mechanical packing and mass transfer increase.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.985-990
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• 2001

The widened Seoul-Bridge is the first continuous 8-span prestressed concrete(PSC) girder bridge in domain. The construction sequence of the bridge consists of S steps in a large way. The measuring in construction stage includes the determination of the allowable fluctuation value of beam stress in each step and the measurement beam stress during prestessing. The measured tendon prestress force was compared with the design value. When it was compared with the analytic result, the difference between the measured stress and the analytic stress was below allowable error. The friction loss and the anchorage slip loss of the tendon prestress force was lower than the design loss value.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.242-245
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• 2003

A garter spring, which is a long, special, close-coiled extension spring with its ends joined to form a ring, is used in tulip contactor between vacuum circuit breaker and bus bar in switchgear. To carry short-time current and resist welding at the contact surface in the tulip contactor, the garter spring must transmits an uniform contact force to the contact surface through the contact chips arranged in the circumference of bus bar. In this paper, the system for measurement of the contact force by the garter spring is developed. Using the developed measurement system, the design of the connection structure including the garter spring is reviewed to obtain the uniform contact forces in all of contact chips.

• Journal of Sensor Science and Technology
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• v.29 no.5
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• pp.336-341
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• 2020

The deflection and null balance methods are used for precision force measurement in the precision industry. Since both methods are based on deformation, the performance of the load cell mechanism is important. In this study, the design variables were obtained via the free body diagram of a lever-linked Roberval mechanism (combined with a flexible hinge link and a Roberval mechanism), and the design characteristics were analyzed according to the weight method. Based on the design characteristics, the optimal design was conducted according to the weight method and FEM was used to verify its reliability.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.601-610
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• 1993

With the purpose of labour reduction in tea plucking operation with portable type machine, the influence of frame angles and tea leaves weight on the grasping forces of each finger were investigated. At the measurement of the grasping force of each finger except for thumb, grip strength dynamometers were attached at the grasping position of the frame instead of handle grips. A series of measurement was carried out changing frame angles of the tea plucking machine and the weight of tea leaves. With the obtained results of the experiments , the influences of the frame angles and the weight of the tea leaves on the grasping forces of each finger were analyzed. Some reasonable suggestions for the labour reduction in the tea plucking operation with portable type machine were obtained in the aspect of normalizing the balance of the grasping force on each finger and these suggestions are expected to contribute the labour reduction of the tea plucking operation.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.2
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• pp.10-19
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• 1996

This paper presents a finger-shaped multisensor system which can measure the tyep and position of a target surface by contactl. The multi-sensor system consists of a sphere-shpaed optical tactile sensor located at the finger tip and a force/torque sensor located at the joint of a finger. The optial tactile sensor determines the type and position of the target surface using the shape and position of the CCD image of the touching area generated by a contact between the sensor and the taget surface. The force/torque sensor also determines the position and surface normal vector by applying the distributionof forces and torques t the contact point to the equations of finger shape. The measurements on the position and surface normal vector at a contact point obtined by two individual sensors are fused using a statistical method. The integrated sensor system has 0.8mm error in position measurement and 1.31$^{\circ}$ error in normal vector measurement. The developed sensor system has many applications, such as autonomous compliance control, automatic grasping and recognition, etc.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.203-206
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• 2006

The drawbeads, which is used for controlling the flow of the sheet by imposing the tension and for preventing the springback in the sheet metal forming process, affects a lot the formability because of the differences in the restraint and opening forces according to the drawbead shapes and dimensions. In this study, the experimental device enabling to measure the drawbead restraining forces and the drawbead opening forces associated with various drawbead shapes and dimensions and their theoretical evaluation are introduced and verified through the experimental measurement of those of a circular drawbead.