• Journal of KSNVE
• /
• v.8 no.3
• /
• pp.533-541
• /
• 1998

Recently, optical disk drives are increasingly demanded to have higher speed as well as high information density, especially for applications like CD ROM drives. To this end, improvement of their optical pickup structure and control is recognized the very challenging issue. In this paper, the pickup is first analytically modelled in a plane to describe its coupled auto-focusing and auto-tracking motions. Subsequently, the model is linearized and combined with actuator dynamics for the auto-focusing system. With its unmeasurable parameters being estimated based on experimental data, an approximate I-DOF linear model is obtained neglecting the coupling term. To design the high speed and robust positional servo controller realistic design specifications are addressed, and H control method is employed based on the approximate model. Finally, taking the pickup in a commerical high speed CD ROM drive as an example performance of the designed controller is verified through realtime experiments.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.11
• /
• pp.152-161
• /
• 1996

This paper descrisbes the implementation of a 20D DCT that can be used for video conference, JPEG, and MPEG-related applications. The implemented DCT consists of two 1-D DCTs and a transposed memory between them, and uses ROM-based multipliers instead of conventional ones. As the system bit length, the minimum bit length that satisfies the accuracy specified by the ITU standard H.261 was chosen through the simulations using the C language. The proposed design uses a dual port RAM for the transposed memory, and processes two bits of input-pixel data simultaneously t ospeed up addition process using two sets of ROMs. The basic system architecture was designed using th Synopsys schematic editor, and internal modules were described in VHDL and synthesized to logic level after simulation. Then, the compass silicon compiler was used to create the final lyout with 0.8um CMOS libraries, using the standard cell approach. The final layout contains about 110, 000 transistors and has a die area of 4.68mm * 4.96mm, and the system has the processing speed of about 50M pixels/sec.

• The Journal of Korean Physical Therapy
• /
• v.22 no.1
• /
• pp.1-7
• /
• 2010

Purpose: Stretching exercises are commonly used in conjunction with sports and rehabilitation. Weassessed the immediate effects of stretching on passive stiffness of the hamstring muscles and knee range of motion (ROM) using three stretching techniques. Methods: A total of 45 participants were recruited. Isokinetic equipment was used to measure the passive stiffness of hamstring muscles and an inclinometer was used to measure active and passive ROM of the knee joint pre and post stretching. Stiffness was then calculated based on the incline of the torque-angle relationship. The test conditions for Group I were $3{\times}30$ seconds of static stretches using the hamstring muscle, Group II were $3{\times}30$ seconds of static stretches using the hamstring muscle with ankle dorsiflexion, and Group IIII had $3{\times}30$ seconds of active stretching. Results: Group II had significantly higher excursion of active ROM and Group IIIhad significantly higher excursion of passive muscle stiffness. All of the groups had significantly higher active and passive ROM and significantly lower muscle stiffness after stretching. The participants showed no change in hamstring muscle stiffness on the following day. Conclusion: Stretching has significant acute effects on ROM and muscle stiffness and canbe used in warm-up protocols for reducing muscle stiffness before a variety of exercise programs.

• Physical Therapy Korea
• /
• v.20 no.1
• /
• pp.47-54
• /
• 2013

The purpose of this study was to compare the immediate effects of upper trapezius muscle stretching in more tensed position (MTP) and less tensed position (LTP) on the change of range of motion (ROM) for neck rotation, and the ROM for conjunct neck motions at end-range of neck rotation toward the painful side in patients with unilateral neck pain. Eighteen patients with unilateral neck pain were recruited for the study's MTP group, and 18 age-, weight- and gender-matched patients with unilateral neck pain were recruited for LTP group. The ROM changes in active neck primary and conjunct motions were measured using a cervical ROM inclinometer in the sitting position. Our results showed that both upper trapezius stretching method in MTP and LTP were significantly effective in increasing the ROM of neck rotation toward painful side in patients with unilateral neck pain. However, a significantly greater increase in the ROM for neck rotation and a further decrease in conjunct neck extension during neck rotation toward the painful side were shown in MTP group, compared to LTP group. The upper trapezius stretching in MTP is useful in increasing the ROM of neck rotation and decreasing the range of conjunct neck extension during neck rotation toward the painful side in patients with unilateral neck pain.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.18 no.4
• /
• pp.111-116
• /
• 2018

In this thesis, the range of motion of the joint was measured using a flexible sensor without using a goniometer, and the measured values were transferred to a smart device. Current range of joint motion measurement is measured by a person using a goniometer. Since the method of measuring by a person is different according to the measuring method and position of the measuring person, it is difficult to make consistent measurement, and an error may occur. The sensor for measurement is a flexible sensor that measures the resistance value that changes according to the movement of the joint. The sensed value can be transmitted to the smart device wirelessly through the ROM sensor node. Also, the sensed analog values were converted to digital values using an ADC. The converted value can be transmitted to the smart device wirelessly through the sensor node. The developed ROM measuring device can perform more consistent measurement than the measurement using general articulator and real time monitoring by interlocking with smart device, so that rapid diagnosis according to the movement of the joint can help the patient's rapid treatment and rehabilitation medical advancement will be.

• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.36D no.5
• /
• pp.36-43
• /
• 1999

A new design of a Direct Digital Frequency Synthesizer(DDFS) is presented, where a pipelined Coordinate Rotate Digital Computer(CORDIC) circuit is employed to calculate amplitude values of all the phase angles of sinusoidal waveforms produced. a near-optimal number of pipeline stages is determined based on an error analysis of calculated amplitude values in terms of the number of bits. The DDFS was implemented using a field programmable gate array, yielding a stable operating frequency of 11.75MHz. The measurement results show higher resolution, faster operating speed and simpler fabrication process, compared to ROM-based counterparts. The CORDIC-based DDFS yields 5 times higher resolution than conventional ROM-based versions.

• Convergence Security Journal
• /
• v.15 no.3_1
• /
• pp.99-105
• /
• 2015

A typical SRAM-based PUF is used in random number generation and key exchange process. The generated out puts should be preserved, but the values are changed owing to the external environment. This paper presents a new D-PUF logic employing a dual anti-fuse OTP memory to the SRAM-based PUF. The proposed PUF can enhance the reliability of the logic since it can preserve the output values. First, we construct the OTP memory using an anti-fuse. After power up, a SRAM generates the random values owing to the mismatch of cross coupled inverter pair. The generated random values are programed in the proposed anti-fuse ROM. The values that were programed in the ROM at once will not be changed and returned. Thus, the outputs of the proposed D-PUF are not affected by the environment variable such as the operation voltage and temperature variation, etc. Consequently, the reliability of the proposed PUF will be enhanced owing to the proposed dual anti-fuse ROM. Therefore, the proposed D-PUF can be stably operated, in particular, without the powerful ECC in the external environment that are changed.

• Journal of Korea Water Resources Association
• /
• v.31 no.1
• /
• pp.105-113
• /
• 1998

Reservoir operation during flood period can be divided into two parts: One is for an operating policy during flood period to consider water conservation and flood control, and the other is for flood time on a random water level at flood forecasting, This study is concerned with reservoir operation and discusses general reservoir operation at flood time. Flood control has problems such as the uncertainty of hydrologic models. technical limitations and some constraints. Therefore, we may prepare the quantitative flood control methods based on the assured flood control storage for reservoir operation. Transformed Reservoir Flood(TRF) Reservoir Operation Method(ROM) is a procedure which determines the adequate releases with considering dam safety for flood inflows over non-damaging discharge. Based on the TRF ROM which was explained in our published paper. the study discusses the TRF ROM with additional investigations and the general reservoir operation rules at flood time.

• Journal of Korean Academy of Nursing
• /
• v.31 no.6
• /
• pp.1067-1076
• /
• 2001

This study was to developed to create a CD-ROM and an educational program for the prevention of sexual harassment and violence and to contribute to the perception and add to the coping of the victims of sexual harassment and violence as well as the child, parents, and teachers. Method: The study's methods were literature reviews, surveys, and assessments of the negotiation process for educational needs of sexual harassed and abused children. Result: The sexual harassment and violence prevention program will contain four subjects : 1) sexual development of a preschool child, 2) characteristics of sexual harassment and violence of a preschool child, 3) safe sex, early detection of sexual violence syndrome, and coping strategies. The CD-RON was composed from three sites. The first was a child site, the second was a parent/teacher site, and the third was a game site for evaluations. The child site consisted of 10 possible scenarios of sexual harassment and violence that a child could experience. The parent/teacher site consisted of knowledge and information for prevention and coping strategies for sexual harassment and violence. At the end of each situation question and answer sections that were used for formative evaluation. Also, the game site could be a summative evaluation. Conclusion: The effects of this program and the CD-ROM were based of the promotion of reverence for humanity and gender equality for preschool childen. Eventually, children, parents, and teachers will have prevention and coping ability that will reduce the occurrence of sexual harassment and violence in Korea

• Proceedings of the IEEK Conference
• /
• 2002.07c
• /
• pp.2051-2054
• /
• 2002

In this research, we had two experiments. In the first experiment we focused on the comparison of loaming between two groups of hearing impaired students (multimedia training group and traditional print-based method group). The results from the first experiment indicated that there was no numerical difference in test scores between the two groups of students but the students enjoyed learning with computer. We then carried out the second experiment. This time, we focused more on measuring the qualitative nature of the learning using multimedia technology. The results of the second experiment indicated that the two methods of teaching and learning affected students similarly since the average scores of both groups showed no statistically significant difference. About 89% of the students in the second experiment enjoyed learning from the CD-ROM. This result was based not just on the CD-ROM Life in Saskatchewan, but included any kinds and subjects of CD-ROM used in the classroom. Although multimedia training is as good as, but no better than, the traditional print-based method, multimedia can be used as a valuable supplement in adaptive technology.