• Proceedings of the KSME Conference
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• 2000.04a
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• pp.556-561
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• 2000

This paper deals with the control of an active bending actuator fur a catheter. The bending actuator with 40mm in length utilizes three zigzag SMA (shape memory alloy) springs which are equally located in the circumference between inner $({\phi}2.5 mm)$ and outer $({\phi}3.0mm)$ tube. It is purposed on realization of desired bending angle $(90^{\circ})$ and direction $(360^{\circ})$. It is also installed in front of the catheter and used to guide a path at extremely bent or branched blood vessel. The performance-analysis of the bending actuator are investigated fur the purpose of optimizing the control of the bending actuator. The analog joy stick is used to command a bending angle and direction for the fast and accurate response. According to the commands of the joy stick, tensile force of each SMA spring is computed and obtained by controlling the temperature of each SMA spring using PWM (pulse width modulation) of supplied electric power.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.396-399
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• 1995

In this study, Acquisition system is proposed to acquire 3 dimensional data of the free surface model using direct pulse control to machining center. Todo this, I/F to connect between manual operating handle and computer is made, and 3 dimensional shape measuring algorithm using Z-map is applied. The 3 dimensional shape data of the free surface model measured by laser displacement sensor and electric touch probe are achieved directly. Performance of the proposed system is evaluated through measurement of various shape model.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.210-214
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• 2007

Silicon nanoparticles are widely studied as a material with great potential for wide applications. For application to present industry, it should be easy to control the characteristics of nanoparticle including the size and structure. In this paper, we investigated the formation of Si nanoparticle using pulse plasma technology. Plasma technology is already quite common in device industry and the size of nanoparticle can be easily controlled according to plasma pulse duration. An inductively-coupled plasma chamber with RF power (13.56 MHz) was used with DC-biased grid $(-200\sim+200\;V)$ installed above the substrate. In order to measure the shape and size of nanoparticle, TEM was used. It was found that the size of nanoparticles can be controlled well with the plasma pulse duration and the collection efficiency is increased with the use of either negative or positive DC-bias.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.198-202
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• 2009

Split Hopkinson pressure bar(SHPB) is used to obtain compressive stress-strain data and deformation characteristics of brittle materials such as rock and concrete. SHPB demands both dynamic stress equilibrium condition and nearly constant strain rate before the failure of the specimen. Pulse shape technique, which places a thin metal disk between launched impact bar and incident bar, should be adopted to satisfy both conditions. In this study, metallic disks with various shapes were used to control the incident impact wave. The results show that the peak value of stress and the length of waves increased with decreasing thickness and diameter of the pulse shaper. In order to investigate shape and strain rate-dependency of the pulse shapers, dynamic compressive stress-strain curves were obtained and analyzed.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.45-48
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• 2003

This research presents an approach to simultaneously detect the faults and measure the length of the electric cables. This approach is easy to use and inexpensive. Moreover, it can be applied to any kinds and sizes of the electric cable. This paper uses 750V $4{\times}4$ Sq.mm. cables. The concept is to send the 2 kHz pulse into the electric cable. When the pulse bumps into the fault, it bounces back. Then, the total time the pulse travels back and forth and the shape of the pulse after bumping are inspected using the pulse detector and pulse converter. Next, the signal obtained is modulated with 10 MHz carrier pulse to segregate into several small pulses before sending to 8-bit counter. The length of the electric cable can be obtained using microcontroller and the location of the faults can be seen on the LCD screen. This approach can be used to inspect the electric cables with the length of at least 15 m.

• Korean Journal of Oriental Medicine
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• v.14 no.3
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• pp.113-119
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• 2008

In pulse diagnosis, the indentation pressure is one of the most important factors as well as the change of pulse shape and the distribution of pressure via time. But, on the oriental medical doctor's indentation pressure control, the understandings of the neurophysiological meanings and mechanisms have been lacked. So, in this paper, we considered on these issues and then proposed a proper system which can imitate the OMD's indentation pressure control mechanisms. As a result, both tactile information and kinesthetic information were found to be essential to the indentation pressure control so that a system, which can measure both the physical indent pressure and the displacement of an indentation arm, has been proposed. With this proposed system, while the indentation was being controlled through the moving step number of the step motor, the physical indentation pres sure and displacement of the indentation arm were measured. From these measured data, the relationships between the moving step number and both physical indentation pressure and displacement were revealed to have linear characteristics in early phase and to have nonlinear characteristics in latter phase. Additionally, three types of graph were generated whose X axis means the moving step number, the physical indentation pressure and the displacement respectively and Y axis means the pulse pressure. By comparing these graphs, we come to conclude that different concepts on indentation pressure control cause different diagnostic results on floating/sinking degrees for the same subject. Consequently, an indentation system for the pulse diagnosis should be able to provide both the tactile information and kinesthetic information, that is, the physical indentation pressure and the displacement of the indentation arm. In future, the proposed system should be optimized to the pulse diagnosis environment and how to combine the both information for more reliable diagnosis should be studied.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.3
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• pp.729-736
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• 2010

In this study, a magnetic stimulation (MS) device with controllable pulse forming technology and pulse shape (MS) is described. The MS device uses an IGBT with appropriate snubbers to switch coil currents up to 6 kA, enabling pulse forming technology control from 5 s to over 100 s. The induced electric field pulses use 2% - 34% less energy and generate 57% - 67% less coil heating compared to matched conventional cosine pulses. MS is used to stimulate rhesus monkey motor cortex in vivo with pulse forming technology of 20 to 100 s, demonstrating the expected decrease of threshold pulse amplitude with increasing pulse forming technology. The technological solutions used in the MS prototype can expand functionality, and reduce power consumption and coil heating in MS, enhancing its research and therapeutic applications.

• Journal of Industrial Technology
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• v.29 no.B
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• pp.127-131
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• 2009

This paper presents the development of smart counting system that is proper for grains with uneven unit weight or shape. This device can detect the small differences of a light beam and count the pulse from wave shape control, when the grain is going on the light screen, which is made by the light beam screen sensor. It can, different from the former conventional device, distinct the uneven grains for counting detect, by using the dedicated hardware and the software algorithm of the light sensor.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.808-812
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• 2003

We need a lot of manpower and we can cut down a labor cost by applying industrial robots the footwear bonding automation process. In this study, we suggest how to program off-line robot path along a shoe's outsole shape in the footwear bonding process by 5-axis microscribe system like robot arms. This microscribe system development consists 5-axis microscribe mechanics, signal processing circuit, and PC with software. It is the system for making database of a shoe's outsole through the movement of a microscribe with many joints. To do this, first read 5-encoders' pulse values while a robot arm points a shoe's outsole shape from the initial status. Then, calculate a relative shoe's outsole by Denavit-Hatenberg's (D-H) direct Kinematics of known length of links and coordinate values. Next, calculate the encoders' pulse values of the robot arm's rotation and transmitting the angle pulse values to the PC through a circuit. Finally, it is able to display a shoe's outsole at real-time by computing the Denvavit-Hantenberg's (D-H) direct kinematics in the PC. With the coordinate values calculated above, we can draw a bonding gauge-line on the upper. Also, we can make off-line robot path programming compute a shoe's bonding area on the upper. These results will be effectively applied for programming a robot path on off-line and automatically.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.168-171
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• 2002

In this study. a solid-state laser system adopting a sequential discharge method in which three flashlamps are turned on sequently was designed and fabricated to examine the pulse width and the pulse shape of the laser beams depending upon the changes in the lamp turn-on time. That is, this study shows a technology that makes it possible to make various pulse shapes by turning on three flashlamps sequently with the aid of a PIC one-chip microprocessor. With this technique, the lamp turn-on delay time can be varied more diversely from a to lamp and the real-time control is possible with an external keyboard, enabling various pulse shapes. In addition, longer pulses can be more widely used for industrial processing and lots of medical purposes.