• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.361-364
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• 2009

KEPRI has studied planar type SOFC stacks using anode-supported single cells and kW class co-generation systems for residential power generation. A 1kW class SOFC system consisted of a hot box part, a cold BOP part and a water reservoir. A hot box part contains a SOFC stack made up of 48 cells with $10{\times}10cm^2$ area and ferritic stainless steel interconnectors, a fuel reformer, a catalytic combustor and heat exchangers. Thermal management and insulation system were especially designed for self-sustainable operation. A cold BOP part was composed of blowers, pumps, a water trap and system control units. When a 1kW class SOFC system was operated at $750^{\circ}C$ with hydrogen, the stack power was 1.2kW at 30 A and 1.6kW at 50A. Turning off an electric furnace, the SOFC system was operated using hydrogen and city gas without any external heat source. Under self-sustainable operation conditions, the stack power was about 1.3kW with hydrogen and 1.2kW with city gas respectively. The system also recuperated heat of about 1.1kW by making hot water. Recently KEPRI developed stacks using $15{\times}15cm^2$ cells and tested them. KEPRI will develop a 5 kW class CHP system using $15{\times}15cm^2$ stacks by 2010.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.3
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• pp.563-572
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• 2001

A conventional motor in a crane has a taco generator to feed back the number of turns to a main controller. The taco generator is contacted to a motor shaft through the coupling. Errors in a crane have often occurred because the coupling has worn out while the motor is turning. In this paper, we design the device of the frequency to voltage transducer in a motor. The device is composed of a rotary encoder, a speed measurement using PIC16F84 controller, a display, and a direction-decision block. The rotation of a motor is recognized by the rotary encoder and microcontroller counts the number of turns of a motor. The emergency signal is generated if the frequency goes over or below the speed limit of a motor. And the device can acknowledge the rotation direction of the motor after 6。 rotation. The simulation results and the test for a implemented device have shown that the transducer of a frequency to a voltage can replace a taco generator in a crane.

• Korean Journal of Agricultural Science
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• v.42 no.1
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• pp.63-71
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• 2015

Path planning is an essential part for traveling and mowing of autonomous lawn mower tractors. Objectives of the paper were to analyze operation patterns by a skilled farmer, to extract and optimize waypoints, and to demonstrate generation of formatted planned path for autonomous lawn mower tractors. A 27-HP mower tractor was operated by a skilled farmer on grass fields. To measure tractor travel and operation characteristics, an RTK-GPS antenna with a 6-cm RMS error, an inertia motion sensing unit, a gyro compass, a wheel angle sensor, and a mower on/off sensor were mounted on the mower tractor, and all the data were collected at a 10-Hz rate. All the sensor data were transferred through a software program to show the status immediately on the notebook. Planned path was generated using the program parameter settings, mileage and time calculations, and the travel path was plotted using developed software. Based on the human operation patterns, path planning algorithm was suggested for autonomous mower tractor. Finally path generation was demonstrated in a formatted file and graphic display. After optimizing the path planning, a decrease in distance about 13% and saving of the working time about 30% was achieved. Field test data showed some overlap, especially in the turning areas. Results of the study would be useful to implement an autonomous mower tractor, but further research needs to improve the performance.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.1
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• pp.113-118
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• 2012

Mulching vinyl is used on field crops to reduce herbicides and this causes multiple effects. The mulching vinyl must be collected for the next crop season, but was left alone due to a shortage of labor. The used mulching vinyl that was left alone acted as one of the main sources of environmental pollution on farms. In order to solve these problems, a self-propelling vinyl remover was developed. The self-propelling vinyl remover consists of a travelling part and rotating of remover wheel. Each output device has a 1.5ps engine and a 2.5ps engine. The vinyl was twisted 17~47cm/times length. The bobbin's diameter was 160mm and it's stable travelling speed was 0.5m/s. The revolution of the remover wheel bobbin was 60rpm to maintain the wheel's linear velocity. As seen at performance test at the field which had 950mm ridge intervals and 10a area, the average working speed was 0.56m/s and the turning time was 15seconds. Therefore, the working performance was 40.1min/10a.

• Journal of Korean Academy of Nursing
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• v.30 no.3
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• pp.647-658
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• 2000

The purpose of this study was to determine the effect of Korean traditional dance movement training on balance, gait and leg strength in elderly women who are forced to remain at home. Fifteen elderly women of an experimental group between the ages 65 and 75 years who have normal vision and passed the hearing and Romberg test, participated in the 12 weeks' dance movement training. Fourteen subjects of a control group were selected. Korean traditional dance movement training was developed on the basis of Korean traditional dance and music by the authors. It took approximately 50 minutes to perform the dance movement program. The subjects of the experimental group practiced dance training for 3 times a week during 12 weeks. During the 50 minutes workout, the subjects practiced 15 minutes of a warm-up dance, 25 minutes of a conditioning dance, and 10 minutes of a cool-down dance. The intensity for the conditioning phase was between 60% and 65% of age-adjusted maximum heart rates. The balance, gait and leg strength were measured prior to and after the experimental treatment. Total balance scores of the experimental group were significantly higher than those of the control group. Scores of sternal nudge, one leg standing balance and reaching up among 13 items have significantly increased after the dance movement training. Total scores of gait of the experimental group were significantly higher than those of the control group following the korean traditional dance movement training. Scores of experimental group in step height, path deviation and turning while walking among 9 items have increased significantly following 12 weeks of dance movement training. The leg strength of experimental group was significantly higher than those of the control group following the Korean traditional dance movement training. The balance, gait and leg strength have significantly correlated in the experimental group following the Korean traditional dance movement training. The results suggest that Korean traditional dance movement training can improve balance, gait and leg strength in home bound elderly women.

• Journal of the Korean Professional Engineers Association
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• v.19 no.4
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• pp.22-29
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• 1986

1) The recipe for tea is to mix tea leaves or tea buds with odorous pharmaceuctial materials, which are boiled and drunk, addition of honey only to that odorous pharmaceutical meterials without adding tea buds to that can be used. 2) Viewed from the part of tea plant the fruit of it accoupies most. The cereal does as much. 3) what we have referred to from the records on this subject are "Guogapylyong" which is of the yuan dynasty and "Jeungbo-Salymkeongje" which is of the Yi dynasty, based on which no trace of pure tea can be found but odorous pharmaceutical kinds of tea only were widely spread. 4) The characteristics of tea are to help make stomach strong, mind cleared, the lungs copious, counteract, and quench thirstiness. The tea help build liver as well as bring about health. 5) As a result of sense test, those kinds of tea were much better than contemporary kinds of teas as far as flovor and sweetness are concerned. Those teas had complex tastes, while teas of to day have simple one. 6) Because the history not so clear before the periods of Unified Sila that the recordings of teas are rare, we can hardly know about tea. Our ancestors really began to drink teas from the period of Unified Sila on. This country turning to the Koryo dynasty, tea drinking manner began to prevail so much that drinking tea became a ceremony. Daring the Yi dynasty it was much camplicated to make and boil the leaf tea. As a result of the previous fact pure tea came to have disappeared and odorous pharmaceutical became prevailent. 7) For value of exploiting Kungjuk tea (ginger tea seasoned with phyllostachy and addition of honeyl) was the highest among many. The worth of developing all the teas among all the beverages was regarded as that high of 51%, while even the tea regarded as worthless obtained 4％ of support, which is the lowest.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.2
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• pp.141-152
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• 1996

Many eastern females concern themselves about the condition and the color of their skin. The purpose of the present study is to classify the skin trouble and the change of the facial color due to hormonal cycle in female. We examined the actual cricumstances by questionnaires, and made patch tests of methyl nicotinate, representing rubefacient, to estimate the epidermal penetratin rate, and measured the facial color change during the menstrual cycle period to invest the correlation factors between skin trouble due to cosmetics and facial color change. Fifty-two percent of subjects had skin trouble relating to cosmetics. One second of subjects with skin trouble due to cosmetic complained the change of sysptom by menstrual cycle. The changes of systptom were related on premenstrual period. The skin trouble developed mainly on the first trimester of the pregnancy. In patch test of methyl nicotinate, most cases showed decreased threshold of the reaction on minstruation, and other cases showed increased reactivity of the skin of menstruation. In facial color measurements, it proves in the appearance of red spot, darkness, increasing the value and turning the hue to yellowish, Also it demonstrates that premenstruation hue turn red and value level decrease. During the period, facial color turns pale and hue progress to yellow. This fact coincides with the questionnaire. We have quqntified through questionnaire, which demonstrates it has good correlation with done to the subjects among the internal environment factors hormonal cycle influences the facial color change and the skin trouble due to cosmetics. Through this paper the development of an more fragmented make-up and skin care products is required to increase the interest to females, to make true the creation of beauty.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.515-520
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• 2020

The design and actual implementation of the four-bar parallel link was studied in the paper. The parallel four-section link is widely used as a basic kinematic mechanism for transmitting the rotation of one axis to the rotational motion of the other axis. However, the parallel 4 link has a problem that phase reversal occurs at the turning point during the movement. In order to prevent the link reversal, it is known that a double parallelogram-type link is formed by attaching an additional phase reversal suppression link with an offset. However, as a result of the actual fabrication experiment, the movement is not smooth at the transition point. In order to solve this problem, in this study, a link for smooth movement is added in addition to a link that provides an offset to prevent phase reversal, so that the phase reversal does not occur at a specific point when the driven shaft rotates along the drive shaft. The test result confirms the validity of our suggestion.

• Journal of Convergence for Information Technology
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• v.10 no.3
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• pp.31-37
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• 2020

The study was investigate the effect of Climacteric Symptom and Self Esteem on depression in middle woman. A questionnaire was completed by 125 D & S city middle aged womans from January to February 2019. data was analyzed using SPSS/WIN 21.0. In addition descriptive statistics and t-test, ANOVA and Pearson's correlation coefficients and multiple regression were used in the data analysis. Differences in depression according to general characteristics of middle-aged women showed significant difference in economic status and health status instability. The variables affecting depression are Climacteric Symptom(β=.409, p<.001), Self Esteem(β=-.368 p<.001), economic status(β=.067 p=353), health status(β=-.094 p=.174). It should be used in the development of social policy nursing policy for menopausal women by confirming the symptoms of menopausal symptoms and depression in middle-aged women and accepting menopausal period as a turning point of natural life.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.54-62
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• 2017

This study was carried to develop the chip-harvester and to analysis the operation productivity and cost for effective collection and forwarding of forest biomass. Main target specification of chip-harvester is speed of 8km/h, maximum climbing capacity of $30^{\circ}$ and maximum load capability of 2000 kg. Body structure is articulate type to reduce turning radius. Driving equipment is six-wheel drive, and a rear wheel is tandem bogie type to increase grip force. As a result of the driving test about developed chip-harvester, driving speed was 6.9 km/hr and 8.1 km/hr in ${\pm}10%$ slope with loaded and 7.3 km/hr and 7.9 km/hr in ${\pm}10%$ slope without load. As a result of the operation productivity and cost, operation productivity of grinding and forwarding was approximately $10m^3$ per day, and operation cost was 393,126 won per day.