• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.3
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• pp.33-39
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• 1994

The purpose of this research is to examine precise linear motion and rotary motion. A six-degrees-of-freedom fine motion mechanism is introduced to drive an object precisely in directions of X, Y and Z-axes and around them : three rectangular linear motion and rotary ones. An experimental mechanism is introduced in which a $70$\times$70$\times$70$\times$(${mm}^3$) cube object is driven by six PZT actuator. The study is to establish the six-degrees-of-freedom fine motion mechanism of linear motion and rotary motion using PZT actuator.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1134-1139
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• 2005

Seismic motion amplification owing to the input motion level at bedrock is one of the important topics to understand various geomaterials behavior. The extremely valuable borehole records at Port Island were obtained during the 1995 Hyogoken Nanbu Earthquake and also before and after the main event. In this study, the seismic motion amplification at the soft reclaimed ground was discussed. Comparison of measured records with numerical simulation results were made with focus on seismic motion amplification characteristics at the soft reclaimed ground.

• Journal of the Ergonomics Society of Korea
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• v.29 no.1
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• pp.73-82
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• 2010

The purpose of this study is to understand motion characteristics of older drivers during reaching seat belt compared to young drivers and to provide design guidelines in order to reduce discomfort for the elderly. The whole body kinematics of each subject was captured using 12-camera motion analysis system. Subjective ratings on discomfort levels were obtained simultaneously using a questionnaire. This paper first presents the result of motion characteristics of elderly drivers' reach motion to seat belt. Compared to young drivers, older drivers performed seat belt reach motions less efficiently and moved slower due to mostly the movement error. Older drivers also made use of reduced joint range of motion in cervical left rotation, lumbar left rotation and right shoulder adduction, which can be explained by their reduced active range of motions (AROMs). To compensate for their reduced joint range of motion, older drivers rotated pelvis more.

• Journal of Biosystems Engineering
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• v.37 no.5
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• pp.279-286
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• 2012

Purpose: This study has been conducted to investigate the applicability of motion analysis of tillage blade for estimation of tillage characteristics of crank-type and rotary-type rotavators. Methods: The interrelation between tillage traces from motion analysis and field test results including rotavating depth, pulverizing ratio and inversion ratio at the same work conditions were analyzed for both crank-type and rotary-type rotavators. The work conditions include working speed of prime mover tractor and PTO speed of rotavators. For the motion analysis, joint conditions of main connecting component were specified considering the actual working mechanism of rotavator. Results: There were important correlations for the trend between motion analysis and field test results. Conclusions: Although further study is needed for applying motion analysis to estimate the accurate tillage related parameters such as rotavating depth, the soil pulverizing ratio and inversion ratio, it could be used to compare the tillage characteristics of various rotavators quickly and simply.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.250-253
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• 2001

This paper describes the effect of step bilge on motion characteristics of FPSO. The purpose of the present study is to investigate motion responses of FPSO with two types of step bilge. Model test result shows that the performance of the bottom type step bilge, that is designed to avoid collision, is as good as that of the side type step bilge.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.266-269
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• 2001

This paper describes the effect of hull form on motion characteristics of FPSO. The purpose of the present study is to investigate seakeeping performance of ship type FPSO in comparison with those of barge type FPSO. Model test result shows that the barge type FPSO is better in heave and pitch motion, while the ship type FPSO is superior in roll motion.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.3
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• pp.273-283
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• 2019

The authors has predicted the maneuvering characteristics of a fishing vessel in deep water using Kijima's empirical formula in a previous study. Since the Kijima's empirical formula was developed by a regression analysis of merchant vessels which have dimensions ($C_b$, L/B, etc.) that are different from those of fishing vessels, it was possible to make a prediction approximately even with inaccurate estimation. In this study, the authors estimated the turning-motion characteristics of a model ship of fisheries training ship in shallow water based on the results of its previous study. The turning-motion characteristics of the model ship in shallow water was found out through quantitative analysis according to the water depth to ship draft ratio (H/d). In conclusion, the turning-motion characteristics of the model ship had significant changes immediately after an H/d 1.5, and this result will be helpful for sailing in shallow water.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.247-250
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• 1996

In this paper, we have examined the impedance characteristics of a tipper link of human being in a positioning motion. Firstly, we have shown the characteristics of the human arm using a bilinear model. From the bilinear model, we have observed that both the driving torque of the forearm and the visco-elasticity of the elbow joint can be controlled by muscles, respectively. Then, we have defined several indexes to show the impedance characteristics. Using the proposed indexes, we have examined the impedance characteristics in the positioning operation. As a result, we can not observe the difference of the impedance characteristics, even if the ease of the positioning motion is varied.

• The Research Journal of the Costume Culture
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• v.25 no.4
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• pp.529-542
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• 2017

The purpose of this study is to utilize technology as basic data for smart clothing product research and development. This technology can recognize user's motion according to characteristics types and functions of wearable smart clothing products. In order to analyze the case of motion recognition products, we searched for previous research data and cases referred to as major keywords in leading search engines, Google and Naver. Among the searched cases, information on the characteristics and major functions of the 42 final products selected on the market are examined in detail. Motion recognition for smart clothing products is classified into four body types: head & face, body, arms & hands, and legs & feet. Smart clothing products was developed with various items, such as hats, glasses, bras, shirts, pants, bracelets, rings, socks, shoes, etc., It was divided into four functions health care type for prevention of injuries, health monitor, posture correction, sports type for heartbeat and exercise monitor, exercise coaching, posture correction, convenience for smart controller and security and entertainment type for pleasure. The function of the motion recognition smart clothing product discussed in this study will be a useful reference when designing a motion recognition smart clothing product that is blended with IT technology.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.7
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• pp.495-505
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• 2009

A two-dimensional circular cylinder freely falling in a channel has been simulated by using immersed boundary - lattice Boltzmann method (IB-LBM) in order to analyze the characteristics of motion originated by the interaction between the fluid flow and the cylinder. The wide range of the solid/fluid density ratio has been considered to identify the effect of the solid/fluid density ratio on the motion characteristics such as the falling time, the transverse force and the trajectory in the streamwise and transverse directions. In addition, the effect of the gap between the cylinder and the wall on the motion of a two-dimensional freely falling circular cylinder has been revealed by taking into account a various range of the gap size. As the cylinder is close to the wall at the initial dropping position, vortex shedding in the wake occurs early since the shear flow formed in the spacing between the cylinder and the wall drives flow instabilities from the initial stage of freely falling. In order to consider the characteristics of transverse motion of the cylinder in the initial stage of freely falling, quantitative information about the cylinder motion variables such as the transverse force, trajectory and settling time has been investigate.