• Journal of Oriental Neuropsychiatry
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• v.15 no.2
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• pp.53-70
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• 2004

Objective : This study was designed to assess the protective effects of Bambusae caulis and St. John's Wort on the animal model of depression, induced by chronic mild stress(CMS) Method : Male Wistar rats were used for this experiment. The subjects were divided into 4 groups ( 1. CMS-drugs: Bambusae caulis administered during CMS treatment, 2. CMS-drugs: St. John's Wort administered during CMS treatment, 3. CMS-vehicle: Water administered during CMS treatment, 4. normal control group without CMS treatment ). After 3 weeks of CMS treatment, they were executed open field test and weight, sucrose intake were measured. Result : 1. CMS Bambusae caulis group showed significant difference of locomotor activities and marginal difference of start latency in comparison with other groups in open field test. 2. There was no change of weights between CMS Bambusae caulis, St. John's Wort groups and CMS control group. 3. CMS St. John's Wort group showed upper level of sucrose intake than CMS Bambusae caulis group and CMS control group. Conclusion : These results suggest that Bambusae caulis may have protective antidepressant effects in CMS model rats. And these effects could be explained by the elevated locomotor activities in open field test.

• Journal of the Korean Institute of Gas
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• v.19 no.1
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• pp.1-5
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• 2015

In general, natural gas is used as GHP(Gas Engine Driven Heat Pump) fuel. On this study, the influences of different natural gas heating value on GHP were evaluated. As a result of engine test & field test using low heating value gas($9,800kcal/Nm^3$) as fuel, the engine power was reduced slightly, however the performance of start-up, the stability of operation and the characteristics of emission gas were almost similar. So it is considered that the normal operation of GHP is possible without any tuning when the low heating value($9,800kcal/Nm^3$) of natural gas was used as fuel.

• The Korean Journal of Community Living Science
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• v.24 no.4
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• pp.583-589
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• 2013

This study was to provide the information for optimum utilization of the air-conditioning system in the human health and energy saving perspective. Subjects were 17 male and female college students(7 males and 10 females) with normal weight. They wore a short sleeved shirt, knee length trousers, socks, and underwear(0.4clo). They were asked to choose the preferred temperature from different environmental temperatures($28^{\circ}C$, $25^{\circ}C$). The physiological responses were measured and the subjective sensation was voted during the step changes of environmental temperature, starting at $28^{\circ}C$ to $25^{\circ}C$ with $1^{\circ}C$ decrease every 20 minutes. The preferred temperature was $25.9{\pm}0.4^{\circ}C$ for males and $26.9{\pm}0.2^{\circ}C$ for females at $28^{\circ}C$ and $24.8{\pm}0.6^{\circ}C$ for males and $25.6{\pm}0.1^{\circ}C$ for females at $25^{\circ}C$. The preferred temperature decreased about $1.3^{\circ}C$ while the environmental temperature changed $3^{\circ}C$. During the environmental step changes, mean skin temperature decreased more in females while the oxygen uptake and rectal temperature were kept constant for both males and females. We found the preferred temperature was affected by the exposed temperature and the thermal sensation in the condition. Subjects preferred a lower environmental temperature when they were exposed to a lower temperature with cooler sensation. Therefore, in the perspective of human health and energy saving, it is recommended to start setting the air-conditioning temperature higher than the preferred temperature.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.904-907
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• 2013

Demand Controller is a control device that if current electric power consumption seems to exceed the targeted amount of electric power, block the connected load devices. When this ON/OFF way is applied to electric power management of electric furnace, start and stop operation of inverter and an electric heater which supplying electric power is being performed repeatedly. This has a problem of life-shortening of inverter and an electric heater by electrical damage. In addition, when electric power supplying is blocked, attemperation is not allowed until return to normal operation condition. In this paper, we develop power management system for electric furnace using the electric furnace remote controller. This system provides the automatic control for approved electric power to electric furnace organically and prevent electric damage of inverter and an electric heater through continuous electric power supply within the targeted amount of electric power.

• Korean Journal of Community Nutrition
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• v.3 no.1
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• pp.21-33
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• 1998

The purpose of this study was to investigate the weight control attempts and related factors among 220 female college students in Seoul. Factors examined included body image, body satisfaction, interest in weight control, beliefs related to weight control, social norms, social expectations regarding subjects' body size and weight change. Data were analyzed using t-test and chi-square test(at $\alpha$=0.05). The average height and weight of subjects were 160.7cm, 52.2kg respectively. BMI and body fat(%) were 20.2 and 25.2%, respectively. One hundred seventy two students(78.2%) had attempted to control their weight, mainly to lose weight, and were categorized as the weight control attempt group. Subjects used diet modification as well as unhealthy method to control weight. 48.2% in the attempt group were underweight or normal weight(by BMI), suggesting that their weight control attempts were was unnecessary. Students in the attempt group described their own size as heavier than those in the no-attempt group(p<0.01) or other girls of their age(p<0.05) ; more dissatisfied with their body size(p<0.01), and showed more interest in weight control(p<0.01). Several differences in beliefs were also noted(p<0.001). The attempt group believed less strongly in the harmful effects or difficulties in weight control and believed more strongly in the advantages of weight control. With respect to social factors, the attempt group perceived that their family and friends wanted them to be smaller than they were(p<0.001), perceived that significant others felt that they should lose weight(p<0.05). These results suggest that educational programs for college female students should start focusing on the harmful effects of excessive dieting and information about desirable weight control methods. Students should be helped to have a correct body image. In addition, educational programs should incorporate strategies to change beliefs regarding weight control, as well as modifying social expectations from significant others.

• Journal of Veterinary Clinics
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• v.26 no.5
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• pp.476-479
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• 2009

Enucleation of a 9-year-old, spayed female Pekingese's right eye was scheduled because of recurrent eyeball rupture caused by chronic corneal ulcer and descemetocele. Scoliosis of the thoracic vertebra was observed on thoracic radiography. Complete blood count, electrolytes, serum chemistry profiles were within normal ranges except of alkaline phosphatase, which was markedly improved, compared with that of five months ago. Severe respiratory sinus arrhythmia was observed before induction of anesthesia, it disappeared after induction. Retrobulbar block was performed with 0.5% bupivacaine, 2% lidocaine, 0.1% epinephrine combination (4 : 1 : 0.2 ratio of volume) before start of surgery. After retrobulbar block, heart rate decreased from 110 to 76 beats/min and sinus arrhythmia recurred. It was considered as oculocardiac reflex caused by increase of intraorbital pressure from retrobulbar block, atropine (0.025 mg/kg, IV) was administered and intermittent positive pressure ventilation was started. Three minutes after atropine administration, abnormal waveform of the electrocardiograph was appeared, it suspected as ventricular or supraventricular tachycardia, so lidocaine (2 mg/kg, IV) was administered. Then, heart rate was maintained around 130 beats/min, and the surgery was finished without the other problems. Although, retrobulbar block is performed to provide analgesia and to prevent oculocardiac reflex in ophthalmic surgery, occasionally it could induce oculocardiac reflex by infiltrated volume.

• School Mathematics
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• v.9 no.1
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• pp.29-44
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• 2007

The aim of statistics education is to enhance statistical thinking. Variability is the key components of statistical thinking. The research has been reviewed preceding research about variability of data. Proceeding from what has been considered above, this research developed learning materials that investigated the concept of variability as it relates to Freudenthal's context by having students sort a particular context. The research is executed the case study evidently aimed at Junior High School 3rd Grade Student's Understanding of Variability. The study of variability in data can be an important start to reach a testing of statistical hypothesis; students reduce data and draw graphs by relating probability distribution to relative frequency and normal distribution. Thus, this study offers basic materials into developing both contents and methods of education need to consider with this sense of purpose held by students to achieve this goal.

• International Journal of Aeronautical and Space Sciences
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• v.6 no.1
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• pp.71-76
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• 2005

The KOMPSAT-1 satellite, launched into a circular sun synchronous orbit on Dec. 21, 1999, entered its$6^{th}$year of successful operation this year. The purposes of the mission are to collect earth images (6.6 m resolution), multi-spectral images of the ocean, and to collect information on the particle environment of the low earth orbit. For normal operation, KOMPSAT-1 orbits are determined using GPS navigation solutions. However, at the start of the life of KOMPSAT-1, the 11-year solar activity cycle was at a maximum. Solar flux was maintained at this level until 2002, and thereafter reduced to a moderate level by 2004. Thus, the OD (Orbit Determination) accuracy has varied according to the solar activity. This paper presents the degree to which the OD accuracy could be degraded during a high solar activity period compared with that of a (relatively) low solar activity period. We investigated the effect of the use of solve-for parameters such as a drag coefficient ($C_D$), solar radiation coefficient ($C_R$), and the general accelerations ($G_A$) on OD accuracy with solar activity. For the evaluation of orbit determination accuracy, orbit overlap comparison is used since no independent orbits of comparable accuracy are available for comparison. The effect of the use of a box-wing model instead of a constant cross-sectional area is also investigated.

• Journal of ILASS-Korea
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• v.25 no.1
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• pp.8-14
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• 2020

Recently, 1-D model-based engine development using virtual engine system is getting more attention than experimental-based engine development due to the advantages in time and cost. Injection rate profile is the one of the main parameters that determine the start and end of combustion. Therefore, it is essential to set up a sophisticated model to accurately predict the injection rate as starting point of virtual engine system. In this research, procedure of 1-D model setup based on AMESim is introduced to predict the dynamic behavior and injection rate of diesel injector. As a first step, detailed 3D cross-sectional drawing of the injector was achieved, which can be done with help of precision measurement system. Then an approximate AMESim model was provided based on the 3D drawing, which is composed of three part such as solenoid part, control chamber part and needle and nozzle orifice part. However, validation results in terms of total injection quantity showed some errors over the acceptable level. Therefore, experimental work including needle movement visualization, solenoid part analysis and flow characteristics of injector part was performed together to provide more accuracy of 1-D model. Finally, 1-D model with the accuracy of less than 10% of error compared with experimental result in terms of injection quantity and injection rate shape under normal temperature and single injection condition was established. Further work considering fuel temperature and multiple injection will be performed.

• Nuclear Engineering and Technology
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• v.20 no.4
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• pp.253-264
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• 1988

Our experience of neutron noise analysis in French-type 900 MWe pressurized water reactor (PWR) is presented. Neutron noise analysis is based on the technique of interpreting the signal fluctuations of ex-core detectors caused by core reactivity changes and neutron attenuation due to lateral core motion. It also provides advantages over deterministic dynamic-testing techniques because existing plant instrumentation can be utilized and normal operation of the plant is not disturbed. The data of this paper were obtained in the ULJIN unit 1 reactor during the start-up test period and the statistical descriptors, useful for our purpose, are power spectral density (PSD), coherence function (CF), and phase difference between detectors. It is found that core support barrel (CSB) motions induced by coolant flow forces and pressure pulsations in a reactor vessel were indentified around 8 Hz of frequency.