• 전기학회논문지
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• 제56권1호
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• pp.1-7
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• 2007

Generally, an electric railroad feeding system has many problems due to the different characteristics in contrast with a load of general three-phase AC electric power system. One of them is harmonics problem caused by the switching device existing in the feeding system, and moreover, the time-varying dynamic loads of rail way is inherently another cause to increase this harmonics problem. In Korea power systems, the electric railroad feeding system is directly supplied from the substation of KEPCO. Therefore, if voltages fluctuation or unbalanced voltages are created by the voltage and current distortion or voltage drop during operation, it affects directly the source of supply. The trainloads of electric railway system have non-periodic but iterative harmonic characteristics as operating condition, because the electric characteristic of the electric railroad feeding system is changed by physical conditions of the each trainload. According to the traditional study, the estimation of harmonics has been performed by deterministic way using the steady state data at the specific time. This method is easy to analyze harmonics, but it has limits in some cases which needs an assessment of dynamic load and reliability. Therefore, this paper proposes the probabilistic estimation method, moments matching method(MW) in order to overcome the drawback of deterministic method. In this paper, distributions for each harmonics are convolved to obtain the moments and cumulants of TDD(Total Demand Distortion), and this can be generalized for any number of trains. For the case study, the electric railway system of LAT(Intra Airport Transit) in Incheon International Airport is modeled using PSCAD/EMTDC dynamic simulator. The raw data of harmonics for the moments matching method is acquired from simulation of the LAT model.

• 한국생산제조학회지
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• 제20권4호
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• pp.502-508
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• 2011

In this paper, we proposed vertical feeding mechanism for a slide parts feeder using the slide type method. This parts feeder of the slide type method have been proposed to suppress the dust generation from the feeding objects. The proposed parts feeder mechanism is composed with the casing hopper, the vertical feeding unit, the in-line feeder and linear shooter unit. And, these mechanisms did modularity through optimum design by means of mechanical and dynamical analysis using the RecurDyn(multi-body dynamics) analysis module. Also were carried out the virtual prototype using the 3-D CAD program. And it had been manufactured as the prototype of the slide parts feeder. The field test for validation of performance was performed directly at the inspection line of bolt and screw. In the field test, this slide parts feeder showed an efficiency of about 1.2 times the bowl feeder. It also showed an epoch reduction in the dust generation compared to the vibration bowl feeder. So this slide parts feeder will be applied useful in the vision inspection system for a screw and bolt.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.1236-1238
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• 2001

The electrified railway has various power supply schemes. Although the identical trains are operated in same condition and the impedance of track are equal, the genealogy impedance of track is changed according to composition method of feeding scheme. So, the collection voltage of train and supplying power from railway substation are greatly unlike. For simulation of collection voltage and power supply according to feeding scheme, using 6-port network analysis proposed previously simulate collection voltage and supply power according to feeding scheme(Parallel Post feeding system, normal feeding system and tie feeding system) and compare and investigate each characteristics.

• 동아시아식생활학회지
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• 제4권1호
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• pp.113-122
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• 1994

This study was designed to assess the current status of infant feeding through an retrospective survey on feeding method. The survey was executed for 417 mothers bringing up a child below 24 months in Seoul and Kyunggi-Do province from September to October, 1993. Analysing a few influential environmental factors while assessing the level of knowledge today's mother have on infant feeding. Incidence of breast feeding was 27.8% of the interviewed mothers, which showed lower percentages than those of previous surveys. This research proved the major influencing factor generally depended on its mother rather than babies. Generally mothers knew the information of infant feeding, but their knowledge actually didn't work. The source of mothers' informations on the infant nutrition showed the grandmother, books and magazines, doctor were many by the order. among the reasons of resent formula and mixed feeding, lack of breast milk' was the commonest as 50.5% and the next reason was 'because of job' as 12.6%.

• 한국직업건강간호학회지
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• 제17권2호
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• pp.155-165
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• 2008

Purpose: The purpose of this study was to investigate the condition, recognition of breast feeding of 273 nurses. Method: Data was collected using a structured questionnaire form April to June 2007. The subjects were 273 nurses in Kyunggido. The data analysis was done with descriptive statistics, $x^2$-test procedures using SPSS/WIN 12.0 PC. Result: There are 23.9% of child day care center, 5.2% of rest room for women, 16.8% of breast feeding room in workplace. Rate of breast-feeding practice was 78.4% of nurses. The reasons why they could not perform the breast-feeding include mother's job(45.4%), lacking breast milk(25.8%). The characteristics of nurses found to be related breast-feeding include age, number of employers. Conclusion: The results showed that the rest supports of the work environment was insufficient to perform breast-feeding in the workplace. These results suggest that nursing intervention for employed mother's breast-feeding practice behavior promotion should focus on characteristics influencing factors on workplace. Also, efficient breast-feeding education program for employed mothers should be developed by continuous qualitative researches based on breast-feeding experiences of employed mothers.

• 한국지반환경공학회 논문집
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• 제4권3호
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• pp.61-67
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• 2003

축산폐수를 처리 시 우선 탈수 후 고상은 퇴비화, 액상을 연속회분식반응기(Sequencing batch reactor, SBR)로 이용하여 처리하는 시스템을 구상하였다. 영양염류 제거를 위한 SBR 공정의 안정적인 운전을 위한 운전모드 결정 실험을 수행하였다. K시 공공축산폐수처리장의 원심분리기에서 나온 유출수를 사용한 실험에서 질소를 제거하기 위한 적정 fill ratio는 1/12, SRT는 15일, 폭기/비폭기 주기는 2시간/1시간이었다. 탈질을 위하여 주입한 외부탄소원으로는 메탄올을 사용하였고 single feeding 방법과 step feeding 방법을 사용하였다. 이 결과 step feeding 방법을 사용시 더 효과적으로 유기물을 사용 탈질효율을 증가시킬 수 있었다.

• 간호행정학회지
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• 제8권4호
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• pp.645-654
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• 2002

Purposes : This study was conducted to examine nursing effects after using a new method of nasogastric tube feeding with recycled PETE bottle making use of gravity, and to compare with those of bolus method using syringe and pressure. Methods : The data collected from patients with nasogastric tube feeding more than a week at an internal medicine unit of C university hospital located in G-city from January 1st, 1998 through June 30th, 2000. For this nonequivalent control group posttest non-synchronized design, 28 patients were assigned to an experimental group and 35 patients to a control group. The homogeneity of two groups and the dependent variables were tested with use of $x^2-test$ and t-test. Results : The duration of hemostatic use was significantly shorter in the experimental group than control group(t=2.63, p=0.02). Also, the patients with PETE bottle feeding had a lower cost of material(t=3.51, p=0.01) and a lower rate of the time of direct nursing care(t=2.44, p=0.04) than those of control group. But, there was no significant difference between two groups in the length of hospital stay. Conclusion : This results indicates that nasogastric tube feeding with PETE bottle is superior to nasogastric tube feeding with syringe. This findings gave us an evidence to enhance nursing effectiveness in clinical setting.

• 여성건강간호학회지
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• 제7권3호
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• pp.382-392
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• 2001

The purpose of this study is to investigate breast-feeding and breast-feeding health behavior among korean first-time mothers and to provide basic data for promoting breast- feeding. Data were collected by interview or self report from 444 first-time mothers who visited health clinic center in the area of metropolitan, medium or small city, countryside. and whose infants were under 12 months old from January 2001 to February 2001. The results show that breast-feeding was 31.5% in a week after childbirth, 25.8% in 4 weeks after childbirth, 22.7% in 2 months, 17.8% in 3 months, 14.3% in 6 months, 2.5% in 12 months after childbirth. Breast-feeding rate was very low in Korea and the duration of breast-feeding was very short. Breast-feeding health behavior did not show significant differences by general characteristics of the subjects except area. The subjects in the health clinic center with MCN project did better breast feeding health behavior than the subject in the health clinic center without MCN project. To raise breast-feeding rate, several strategy could be suggested. Systemic education about importance and advantages of breast-feeding and desirable breast-feeding method should be provided to pregnant women and postpartum women. Childbirth leave in the work should be prolonged, and supportive facility such as nursery room should be installed for working mothers. Hospitals should follow the guideline of 'Baby Friendly Hospital Initiative' which was provided by UNISEF and WHO, including rooming-in after delivery.

• Journal of Animal Science and Technology
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• 제63권6호
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• pp.1453-1463
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• 2021

Feeding is the most important behavior that represents the health and welfare of weanling pigs. The early detection of feed refusal is crucial for the control of disease in the initial stages and the detection of empty feeders for adding feed in a timely manner. This paper proposes a real-time technique for the detection and recognition of small pigs using a deep-leaning-based method. The proposed model focuses on detecting pigs on a feeder in a feeding position. Conventional methods detect pigs and then classify them into different behavior gestures. In contrast, in the proposed method, these two tasks are combined into a single process to detect only feeding behavior to increase the speed of detection. Considering the significant differences between pig behaviors at different sizes, adaptive adjustments are introduced into a you-only-look-once (YOLO) model, including an angle optimization strategy between the head and body for detecting a head in a feeder. According to experimental results, this method can detect the feeding behavior of pigs and screen non-feeding positions with 95.66%, 94.22%, and 96.56% average precision (AP) at an intersection over union (IoU) threshold of 0.5 for YOLOv3, YOLOv4, and an additional layer and with the proposed activation function, respectively. Drinking behavior was detected with 86.86%, 89.16%, and 86.41% AP at a 0.5 IoU threshold for YOLOv3, YOLOv4, and the proposed activation function, respectively. In terms of detection and classification, the results of our study demonstrate that the proposed method yields higher precision and recall compared to conventional methods.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.1226-1228
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• 2001

In this paper, the modified simulation algorithms of the Auto Transformer (AT) feeding electric train were proposed. To obtain terminal voltage of train by using equivalent circuit of the AT feeding system, the iterative method is proposed for which determine the train voltages. The train voltages are iteratively calculated from the system voltage drop and line impedance. In the case study, the proposed method is verified from actual operation data of the Kwa-Chon line. Also it is verified that the proposed method can be extent to the multi-train simulation tool. The terminal voltage of the multi-train can be calculated by using superposition principle and it is easily applied to the proposed method. Therefore, the proposed method can be a solution for the complexity of the circuit analysis in the existing methods.