• Journal of Ocean Engineering and Technology
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• v.30 no.3
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• pp.221-226
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• 2016

An attitude controller for a 6-DOF hovering autonomous underwater vehicle (HAUV) is implemented. We add a vertical thruster, an underwater camera, a wireless communication device, and a DVL to the HAUV that was developed a year ago. The HAUV is composed of 5 thrusters, 2 servo-motors, and 4 apparatus parts. Two rotating thrusters control the surge, heave, and roll of the vehicle. The vertical thruster controls the pitch, and two horizontal thrusters control the sway and yaw of the vehicle. The HAUV’s movement in each direction is controlled by 6 PID controllers. Each PID controller controls the propulsive force and angle of a thruster. In a horizontal and vertical movement experiment, we showed the feasibility of the proposed controller by maintaining a given depth and heading angle of the HAUV.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.1
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• pp.48-56
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• 2008

Nowadays, CMG(Control Moment Gyros) becomes one of the essential actuators for satellite attitude control. The method to define the key requirements of CMG is suggested to avoid CMG's singularity problem for the limited envelope of angular momentum of 2H. Furthermore, the analysis and simulation are carried out to provide a necessary guideline when three CMGs are used for spacecraft control purpose. An improved configuration of redundant four CMG cluster, slightly different from the conventional configuration, is proposed not only to avoid the CMG singularity problem, but to improve agility about roll or pitch-axis.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.2
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• pp.45-58
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• 2011

Gravure off-set printing recently is used in electronics display market. This method has advantages of mass production and high printing speed. It is also fine pattern can be implemented. We have manufactured low-curable conductive Ag pastes for gravure off-set printing. When printing, the pastes be used different silver powder shape because of the printing characteristics. The pastes were prepared with silver powder by silver powder shape and size, epoxy resin, solvent and homogenized on a standard three-roll mill. And the pastes exhibited a shear-thinning flow at viscosity profile. Moreover the adhesive strength and resistivity of silver film had a good characteristics. With the manufactured paste in this study, touch panel had is manufactured and it had $4{\times}10-5{\Omega}.cm$.

• The Journal of Korea Robotics Society
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• v.5 no.4
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• pp.309-317
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• 2010

This paper proposes an efficient measurement system for the velocity and direction of the wind using the dual rotor wind power generator in vessel. Conventional digital measurement system recognizes the direction and the velocity of the wind using the electric compass or synchronous motor and Vane probe method using hall sensors. But each system has its own short-comings: the synchronous motor has a larger measurement error than the magnetic compass and magnetic compass is weak for the external disturbances such as fluctuation of the vessel. To compensate these short-comings, this paper proposes a new compensation algorithm for the fluctuation errors according to the external interference and the unexpected movement of the vessel along the roll and pitch directions. The proposed system is implemented with the dual compasses and a synchronous motor. The proposed independent power generation system can be operated by itself and can raise the efficiency of the wind power generation systems of 30 ~ 400 W installed along the vertical and horizontal axes. The proposed system also realizes the efficient and reliable power production system by the MPPT algorithm for the real-time recognition of the wind direction and velocity. An advanced switching algorithm for the battery charging system has been also proposed. Effectiveness of the proposed algorithm has been verified through the real experiments and the results are demonstrated.

• The Journal of Korea Robotics Society
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• v.5 no.4
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• pp.294-301
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• 2010

In order to produce a convenient robot for the aged and the lower limb disabled, it is needed for the research detecting implicit walking intention and controlling robot by a user's intention. In this study, we developed sensor module system to control the walking- assist robot using FSR sensor and tilt sensor, and analyzed the signals being acquired from two sensors. The sensor module system consisted of the assist device control unit, communication unit by wire/wireless, information collection unit, information operation unit, and information processing PC which handles integrated processing of assist device control. The FSR sensors attached user's the palm and the soles of foot are sensing force/pressure signals from these areas and are used for detecting the walking intention and states. The tilt sensor acquires roll and pitch signal from area of vertebrae lumbales and reflects the pose of the upper limb. We could recognize the more detailed user's walking intention such as 'start walking', 'start of right or left foot forward', and 'stop walking' by the combination of FSR and tilt signals can recognize.

• Herbal Formula Science
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• v.25 no.2
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• pp.209-222
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• 2017

Objectives : The purpose of this study was to investigate the interpretation of the Soyo-san(SYS) prescription in order to obtain the evidence for clinical applications. Methods and Result : We interpreted on the SYS-related contents based on 25 classic books, analyzed it according to followed categories ; meaning of name, alteration of herbal composition according to age, usage, origin, physiological and pathological situation of SYS, description of each herbal drug Conclusion : 1. So(逍) mean diminish(消), 遙 mean roll(搖). It reflected feature of SYS, that alleviate depression without impairing vital energy(正氣). 2. SYS was first mentioned in the prescription of peaceful benevolent dispensary(太平惠民和劑局方), its essential application was harminizing liver depression and spleen deficiency(肝鬱脾虛) 3. SYS originated from Sayuk-san. Sayuk-san was appropriate for soothe the liver and regulate the spleen(疏肝理脾), while SYS was suitable for depressed liver and blood deficiency(肝鬱血虛) 4. Most medical literature insisted that application situation of SYS is blood deficiency(血虛), depressed liver(肝鬱), spleen deficiency(脾虛). And there is strong correlation between three factors. 5. Bupleurum falcatum L.(柴胡), Mentha arvensis L.(薄荷) alleviates liver depression as "pungent dissipate-qi uprais (辛散氣升)" nature. Angelica gigas Nakai(當歸), Paeonia lactiflora Pall.(白芍藥) emoliates the liver by nourishing the blood. Atractylodes japonica Koidz. ex Kitam.(白朮), Poria cocos(茯苓), Glycyrrhiza uralensis Fisch.(甘草), Zingiber officinale Roscoe(生薑) cultivate the basis as tonifying earth(補土).

• Journal of Korean Physical Therapy Science
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• v.2 no.2
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• pp.509-515
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• 1995

The purpose of this study was to assess the rural women's general status in relation with low back pain. This survey was done after teaching them the prevention and treatment of low back pain with Meckenzie Method. 84 rural resident women including rural life guidance. The results were as follows. 1. The average age of rural were $35{\sim}50$ years old and the guidance's age were $21{\sim}25$ years old. The educational level of rural women were highest in primary school(46.67 %) and the home extension worker were college education(83.67 %). 2. 75 % of rural woman complained low back pain while 17.33 % of the home extension worker had back pain. 3. The home extension worker feel the necessity of the education in low back pain(100 %) while 88.89 % of the rural woman agreed. 4. All the rural women and the home extension worker had the concept of back pain and its prevention(100 %). 5. After this education, the confidence in prevention and treatment were each 78.79 % with rural women and 91.84 % with home extension worker. 6. The necessity for the treatment of low back pain were : first, the correction of posture, second, the activity posture correction, third, the supportive roll of back curve. 7. There were no statistical significant outcome specifically.

• Journal of Ocean Engineering and Technology
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• v.22 no.4
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• pp.84-89
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• 2008

It is hard to find experimental data for a model test of small high-speed planning boats. It is difficult to verify the performance seen in a model test for a high-speed boat because the ship-model scale-ratio is very small and the flow velocity of the circulating water channel and the X-carriage speed of the towing tank are restricted. Therefore most hull-form designs for high-speed small boats depend on the sea-trial test result for similar boats or evaluation through numerical calculations. This study investigated the anti-rolling effect of the stern sub-body in a 50-knot doss planning boat. To carry out this work, new model test procedures were set up in the actual sea. Using this method, the anti-rolling effect of the stern sub-body was investigated. A stern sub-body attached to a planning boat was proved to be effective in reducing the roll and pitch angle.

• Journal of Ocean Engineering and Technology
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• v.24 no.4
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• pp.13-22
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• 2010

While a caisson used for breakwater is carried by a floating dock, accompanying stability problem by its existing motions in the dock is quite important and should be pre-checked against sea environmental condition. In the stability analysis, the acceleration, velocity, angle of roll and pitch motions are important to calculate frictional force and separation force. If separation force becomes bigger than frictional force, serious collision may be occurred between caisson and floating dock. In this study, stability evaluation during the transportation of a caisson on floating dock for breakwater was performed by using a commercial program, HydroD and CHARM3D/HARP.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.11
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• pp.1-7
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• 2009

In this paper, a simple analytical model for deriving the threshold voltage of a short-channel intrinsic-body SDG SOI MOSFET is suggested. Using the iteration method, both Laplace equations in intrinsic silicon body and gate oxide are solved two-dimensionally. Obtained potential distributions in both regions are expressed in terms of fourth and fifth-order of the coordinate perpendicular to the silicon channel direction. Making use of them, the surface potential is obtained to derive the threshold voltage in a closed-form. Simulation results show the fairly accurate dependencies of the threshold voltage on the various device parameters and applied bias voltages.