• Journal of Korean Society for Atmospheric Environment
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• v.12 no.1
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• pp.55-66
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• 1996

One-hour average concentrations of ground-level ozone from around 80 monitoring stations in Korea during 1991 to 1993 were analyzed to examine characteristics of the ozone concentration variations. Two types of variations were observed: one was for the Capital area typified by Kwanghwmun, and the other was for the south and east seashore region typified by Tongkwangyang. In the Capital area including Seoul, Inchon, Kyonggi-do and Chunchon, mean daily 1-hout maximum was the highest in June following high monthly averages in spring. But frequent precipitation prevented further rise of daily maximum in July and August even though there were frequent episodes of high concentration exceeding 100ppb. In the south and east seashore region, average concentration was the highest throughout the year, and daily maximum and minimum simultaneously changed owing to small contributions from photochemical reactions. The typical annual variation was spring peak, summer down, and fall rise. Spring peak accompanied an usual observations of background variations at remote sites in the Northern Hemisphere. Riess of average and daily maximum with lower daily minimum in fall were attributable to photochemical reactions.

• Current Photovoltaic Research
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• v.4 no.4
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• pp.131-139
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• 2016

This paper shows the series power device in the massive roof-top PVs and domestic loads. D-UPFC as the series power device controls the distribution voltage during voltage rise (or fall) condition. D-UPFC consists of the bi-directional ac-ac converter and the transformer. In order to verify the D-UPFC voltage control, the distribution model is used in the case study. D-UPFC enables the voltage control in the distribution voltage range. Dynamic voltage control from voltage rise and voltage fall conditions is performed. Scaled-down experimental test of the D-UPFC is verified the voltage control and it is well performed without high voltage spikes in the inductive load.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1564-1572
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• 2010

In this study, the falls detection and direction classification system was implemented using 3-axial acceleration signal. The acceleration signals were acquired from the 3-axial accelerometer(MMA7260Q, Freescale, USA), and then transmitted to the computer through USB interface. The implemented system can detect falls using the newly proposed algorithm, and also classify the direction of falls using fuzzy classifier. The 6 subjects was selected for experiment and the accelerometer was attached on each subject's chest. Each subject walked in normal pace for 5 seconds, and then the fall down according to the four direction(front_fall, back_fall, left_fall and right_fall) during at least 2 second. The falls was easily detect using the newly proposed algorithm in this study. The acquired signals were analyzed after 1 second from generating falls. The fuzzy classifier was used to classify the direction of falls. The mean value of the falls detection rate was 94.79%. The classifier rate according to falls direction were 95.83% in case of front falls, 100% incase of back falls, 87.5% in case of left falls, and 95.83% in case of right falls.

• Korean Journal of Veterinary Research
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• v.46 no.3
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• pp.255-261
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• 2006

Experimental animals have been used to biological and medical purposes and the animals must be, for these purposes, healthy and clean to microbial infection. However, the animals can be easily exposed to pathogenic microorganism via several routes. Of the routes, environmental conditions are the most important factors to keep the animals healthy and clean, especially air condition. Monitoring of air-condition has been required to keep the animal healthy and clean. However, any guideline is not available for experimental conditions with pigs. Therefore, the sampling times and points were compared in different conditions to establish an optimal protocol for monitoring of air borne bacteria. Tryptic soy agar(TSA), blood agar containing 5% defibrinated sheep blood and Sabraud dextrose agar(SDA) were used as media to capture total bacteria, pathogenic bacteria and fungi, respectively. Two methods, compulsive capture using an air-sampler and capturing fall-down bacteria were used to capture the microorganisms in the air. The points and time of capturing were different at each experiment. Air borne microorganisms were captured at three and five points in the open and closed equipments, respectively. Air was collected using an air-sampler for 1 min and 5 min and the agar plates as open status were left from 30 min to 2hr. At first, we monitored an experimental laboratory which dealt with several pathogenic bacteria and then, a protocol obtained from the investigation was applied to open or close experimental conditions with pigs. Number of bacteria was high from 10:00 to 15:00, especially on 13:30-15:30 but sharply decreased after 17:00. The tendency of the number of bacteria was similar between two methods even though the absolute number was higher with air sampler. Critical difference in the number of cells was observed at 5 min with air sampler and 2 hr with fall-down capturing method. However, 1 min with air sampler and 1 hr with fall-down capturing were the best condition to identify bacterial species collected from the air. Number of bacteria were different depending on the sampling points in closed condition but not in opened condition. Based on our results, a guide-line was suggested for screening air-borne microorganism in the experimental conditions with pigs.

• Proceedings of the KAIS Fall Conference
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• 2002.11a
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• pp.238-242
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• 2002

본 논문에서는 3차원 마이크로구조물을 위한 새로운 Thick Photoresist(TPR) 공정 기술을 개발하였다. 일반적으로 Thin Photoresist는 얇은 두께로 코팅을 할 수 있다. 그러나 SU-8과 같은 TRP은 몇 십 ㎛ 또는 그 이상으로 코팅이 가능하고 높은 종횡비를 얻을 수 있다. SU-8과 같은 TPR을 사용하여 마이크로구조물을 제작할 때 TPR의 crack들은 bake시의 갑작스런 tool down에 의한 stress에 의해 나타나는데, 이러한 crack들은 마이크로구조물의 도금을 어렵게 만든다. 본 논문에서는 TPR의 코팅, baking 시간 조절, cool down과 PEB(Post Expose Sake) 시간 조절을 통하여 stress에 의해 발생되는 crack이 없는 3차원 마이크로구조물을 제작할 수 있는 새로운 공정 기술을 개발하였다.

• The Journal of Korea Robotics Society
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• v.7 no.2
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• pp.83-91
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• 2012

In this paper, we propose a cable climbing robot which can climb up and down the cables in the bridges. The robot mechanism consists of three parts: a wheel based driving mechanism, adhesion mechanism, and safe landing mechanism. The wheel based driving mechanism is driven by tooth clutches and motors. The adhesion mechanism plays the role of maintaining adhesion force by a combination of pantograph, ball screw, and springs even when the power is lost. The safe landing mechanism is developed for guaranteeing the safety of the robot during operations on cables. It can make the robot fall down with reduced speed by dissipating the gravitational forces. The robot mechanism is designed and manufactured for validating its effectiveness.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.12
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• pp.198-208
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• 1995

BiCMOS circuit consist of CMOS part which constructs logic function, and bipolar part which drives output load. Test to detect stuck-open faults in BiCMOS circuit is important, since these faults do sequential behavior and are represented as transition faults. In this paper, proposes a method for efficiently detecting transistor stuck-open faults in BiCMOS circuit by transforming them into slow-to=rise transition and slow-to-fall transition. In proposed method, BiCMOS circuit is transformed into equivalent gate-level circuit by dividing it into pull-up part which make output 1, and pull-down part which make output 0. Stuck-open faults in transistor are modelled as transition fault in input line of gate level circuit which is transformed from given circuit. Faults are detceted by using pull-up part gate level circuit when expected value is '01', or using pull-down part gate level circuit when expected value is '10'. By this method, transistor stuck-open faults in BiCMOS circuit are easily detected using conventional gate level test generation algorithm for transition fault.

• Journal of Chest Surgery
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• v.22 no.2
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• pp.364-370
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• 1989

22 Cases of traumatic diaphragmatic injuries treated at the Department of Thoracic and Cardiovascular Surgery in Chon-Buk National University Hospital from Jan. 1979 to Oct. 1988 were reviewed in this study. Of the 22 cases, 18 were male and 3 were female, a ratio of 4.5:1. This ratio revealed high incidence in male patient. The age distribution ranged from 2 to 60 years and mean age was 31 years. The modes of injury were as follows: 11 stab wound, 5 traffic accident, 2 fall down, 2 fighting injury, 1 compression wound by sand bag, and 1 slip down injury. Useful diagnostic tools were chest X-ray with or without radiopaque dye swallowing, which was the most commonly diagnostic, UGI series, and thoracoscope. Operations were performed in 22 cases, and 18 cases were through thoracotomy. The herniated organs through the ruptured diaphragm were stomach, omentum, liver, spleen, colon, and small bowel. There were associated injuries, and the most commonly associated was rib fracture. There was no postoperative death.

• Journal of the Korean Institute of Rural Architecture
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• v.7 no.1
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• pp.129-136
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• 2005

In this paper, barrier panels against falling stones have been studied experimentally with various specimens. Test results show that stiffened barrier panels show more sufficient capacity than unstiffened barrier. Each type barrier panel can be used for various situations. New barrier panel is good for increasing strength and improving environment and maintaining cost down.

• Journal of radiological science and technology
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• v.25 no.1
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• pp.39-48
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• 2002

Earthquake are not frequent in korea but exist. The purpose of this study is to make a fixation(tie up) device against earthquake for radiologic department installation. It is considered that the device will prevent the X-ray equipment fall down, slip, Jumping therefor save the X-ray equipment itself and making possible to examine patients even when occuring earthquake, Discussion on how to make and how to set up was researched.