• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.270-275
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• 2012

This paper describes design of a variable-N frequency synthesizer for RF PLL with $0.13{\mu}m$ silicon CMOS technology being used as an application of the UWB system like MBOA. To get good performance of speed and noise super dynamic circuits was used, and to get variable-N division ratio MOSFET switching circuits was used. Especially to solve narrow bandwidth problem of the dynamic circuits load resistance value of unit divider block was varied. Simulation results of the designed circuit shows very fast and wide operation characteristics as 5~26GHz frequency range.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.8
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• pp.1181-1189
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• 2009

This research analyzes the relationship between the height of the sleeve cap and the mobility of arm movement. Ten Korean women participated as subjects. For test clothes, the AH/4+3, AH/4+1, and AH/4-1 height of the sleeve cap were varied. The sleeve circumference was adjusted according to the variation of the height of the sleeve cap. To analyze test clothing objectively, the range-of-motion of two selected movements (Arm Adduction/Abduction and Arm Flexion/Extension) was measured by Leighton flexometer and goniometer. Also, a wearer acceptability rating was examined for acceptance by the subject. Anova and Duncan's multiple range tests are used for statistical analysis. According to the results, the mobility of test clothing 2 and 3 improved 14.9% and 27.7% in Arm Adduction/Abduction, and 12.7% and 31.9% in Arm Flexion/Extension compared to the test clothing 1.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.1
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• pp.56-61
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• 2011

This paper describes design of a programmable frequency synthesizer for RF PLL with $0.18{\mu}m$ silicon CMOS technology being used as an application of the UWB system like MBOA. To get good performance of speed and noise super dynamic circuits was used, and to get programmable division ratio switching circuits was used. Especially to solve narrow bandwidth problem of the dynamic circuits load resistance value of unit divider block was varied. Simulation results of the designed circuit shows very fast and wide operation characteristics as 1~14GHz frequency range.

• Research in Community and Public Health Nursing
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• v.20 no.4
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• pp.403-411
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• 2009

Purpose: The purpose of this study is to explore the effects of a group movement exercise program on psychophysiological variables in the institutionalized elderly. Methods: This research adopted the non-equivalent control group pretest-posttest design. Twenty elders were selected as an experimental group, whereas twenty-two elders were as a control group. The group movement program consisted of 35 minutes of dance and three days a week for eight weeks. Resting systolic blood pressure, diastolic blood pressure and heart rate were measured in a relaxed sitting position. The range of flexion and extension of joint was measured with a gonimeter. Life satisfaction and self-efficacy were measured by self-report. Data were analyzed through $x^2$-test, t-test and ANCOVA using SPSS/WIN program. Results: The results were as follows: Resting systolic blood pressure, diastolic blood pressure and resting heart rate decreased significantly by the group movement training. The range of flexion and extension of the shoulder and hip joints increased significantly. The scores of life satisfaction and self-efficacy increased remarkably by the group movement. Conclusion: The results suggest that group movement training can be an effective intervention to improve psychophysiological variables and the range of motion for the institutionalized elderly.

• Journal of Korea Multimedia Society
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• v.12 no.5
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• pp.728-736
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• 2009

We propose a method using the genetic algorithm to solve the maximum set cover problem. It is needed for scheduling the power of sensor nodes in extending the lifetime of the wireless sensor network with variable sensing range. The existing Greedy Heuristic method calculates the power scheduling of sensor nodes repeatedly in the process of operation, and so the communication traffic of sensor nodes is increased. The proposed method reduces the amount of communication traffic of sensor nodes, and so the energies of nodes are saved, and the lifetime of network can be extended. The effectiveness of this method was verified through computer simulation, and considering the energy losses of communication operations about 10% in the network lifetime is improved.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.1
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• pp.147-162
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• 1997

When designing workplaces or arranging controls on panel, devices and controls should be placed within the reach of operator's arm or foot to guarantee effective performances. Most of the existing research on the reach volume were based on measurements of a few subject's arm reach, and limited to Caucasian and Chinese populations. Furthermore, reach volume considering foot or trunk motion have not been investigated. Range of human joint motion and that of two degrees of freedom motion are needed to generate reach volume analytically using the sweeping algorithm. However, range of two degrees of freedom motion has not been measured up to now. Therefore, range of two degrees of freedom motion was measured in this research, where 47 college students were participated voluntarily as subjects. The results showed that the motion of one joint can be limited by the motion of another motion, that is to say, the shoulder flexion was decreased significantly when the shoulder was adducted or abducted. Second, new approximate algorithms generating reach volumes were suggested, in which range of two degrees of freedom motion was used as input data. Depending upon the body segment included such as trunk, arm and leg, three types of reach volume were provided, in which the human body was modeled as a multilink system based on the robot kinematics and the sweeping method was employed. Reach volume generated analytically in this study showed statistically reasonable results when compared with that obtained from direct measurement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1051-1057
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• 2009

USN(Ubiquitous Sensor Network) is used to provide many services such as bridge monitoring, cultural properties monitoring, river monitoring, protection of an old and feeble person, management and control of a city and circumstance monitoring, etc. A RF transceiver is needed for implementing USN. In this paper the implementation and the design of a RF transceiver for sensor nodes operating in 2.4GHz frequency band are presented. The design procedure of AGC, a receiver and a transmitter is described. And the performance of the implemented RF transceiver is also tested. The test results of receiver sensitivity, receiver dynamic range, frequency stability, phase noise, output power of transmitter, flatness and spectrum mask are presented.

• Korean Journal of Optics and Photonics
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• v.12 no.4
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• pp.257-262
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• 2001

A Littman type tunable external-cavity diode laser system was developed. The laser output which is the Oth-order diffracted beam from a diffraction grating in an external cavity is a single longitudinal mode. Its FWHM was measured as less than 9 MHz. With the diode driving current of 140 mA and operating temperature of $25^{\circ}C$, the coarse tuning range of 3.475 urn was measured. A fine tuning experiment in which an external mirror was rotated by a PZT driven by a sawtooth wave was performed, and its tuning range of 0.042 urn was measured. sured.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.3
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• pp.31-39
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• 2001

In this paper, we proposed a new pixel circuit of the CMOS image sensor for high dynamic range operation, which is based on a multiple sampling scheme and a conditional reset circuit. To expand the pixel dynamic range, the output is multiple-sampled in the integration time. In each sampling, the pixel output is compared with a reference voltage, and the result of comparison may activate the conditional reset circuit. The times of conditional reset, N, during the integration will contribute to the increase of the dynamic range by the times of N. The test chip was fabricated with 0.65-${\mu}m$ CMOS technology (2-P, 2-M).

• The Transactions of the Korean Institute of Power Electronics
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• v.16 no.4
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• pp.334-341
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• 2011

This paper presents a design and implementation of DC/DC converter with very wide input voltage ranges for EPBS whose input voltage is from 30V to 400V and output voltage is 48V. This converter is comprised of two stages that one is for control and the other is for only galvanic isolation. The proposed converter uses the hard-switched buck-boost topology for control purpose and soft-switched LLC resonant converter for isolation. The proposed converter has been verified with 300W design.