• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.5
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• pp.842-856
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• 1994

The various services that a broadband integrated services digital network (B-ISDN) carries, have a wide range of delay, delay jitter and cell loss probability requirements. Design of appropriate control schemes for B-ISDN is an extremely important and challenging problem. In this paper, we proposed multiplexing algorithm with both delay and loss priorities in order to satisfy the diverse requirements. For the implementation of cell lose priority, we assumed that voice cells are generated as non-discardable(i.e., high priority) and discardable (i.e., low priotity)cells. The low priority voice cell may be discarded inside the network if congestion occurs. The cell dropping scheme is shown to reduce cell losses as well as delays for both voice and data. Such a load shedding scheme is expected to improve significantly utilization of B-ISDN.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1327-1329
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• 2000

The thyristor among the power-semi-conductor elements, which has large current capacity and high voltage, is used widely nowadays. When the thyristor was being used to the long time, this element may be able to arise the system trip caused by changing the characteristic and dropping the performance. Therefore, it would be necessary to analyze the characteristic of element to maintain the stable operation of the system. In oder to analyze this characteristic, it would be need to test forward direction, reverse direction and leakage current by supplying the half-sine wave voltage. Among these testing, transient current condition is generated from the testing of leakage current. This transient current may be the main factor of the error in the precise measurement of leakage current. Therefore, this paper analyzes the relationship between supply voltage and transient current in measuring leakage current of the SCR, and then suggests the condition and cause of transient current as appearing the leakage current in the testing the leakage current.

• Women's Health Nursing
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• v.11 no.2
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• pp.142-147
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• 2005

Purpose: The objectives of this study were to investigate the current breast feeding rates in Jeju Province and to identify factors which influence breast feeding duration after birth. Method: The subjects were 189 women with a child between 12 months and 24 months old. Data was collected using a structured questionnaire from October 2003 to January 2004. Measures used in this study included general characteristics, delivery related characteristics, breast feeding related characteristics and the feeding type over a 12-month period after birth. Result: The study showed that the breast feeding rate in the first month was 63.1%, later dropping to 30.9% in the sixth month. In addition, only 14.2% of subjects were still breast feeding the baby at twelve months of age. The mean of breast feeding duration was 4.77 months. The factors which influenced breast feeding duration were wanted pregnancy, breast feeding education, planning of breast feeding and breast feeding experience. Conclusion: Considering the low rate of long-term breast feeding, the importance of breast feeding should be emphasized to promote and support the continuation of breast feeding in addition to at its initial stage. Based on the results, programs on breast feeding promotion and continuation need to be developed.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2489-2494
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• 2008

The two-dimensional circular cylinder freely falling in a channel has been simulated by using Immersed boundary - lattice Boltzmann method in order to analyze the characteristics of motion originated by the interaction between the fluid and the solid. The wide range of the solid/fluid density ratio has been considered to identify the effect of the solid/fluid density ratio on the motion characteristics such as the falling time, the terminal velocity and the trajectory in the vertical and horizontal directions. In addition, the effect of the gap between the cylinder and the wall on the motion of two-dimensional circular cylinder freely falling has been revealed by taking into account a various range of the gap size. The Reynolds number in terms of the terminal velocity is diminished as the cylinder becomes close to the wall at the initial dropping position, since the repulsive force induced between the cylinder and wall constrains the vertical motion. Quantitative information about the flow variables such as the pressure coefficient and vorticity on the cylinders is highlighted.

• Journal of the Korea Society of Computer and Information
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• v.10 no.4 s.36
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• pp.275-283
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• 2005

In this paper, we propose an overlay transmission method of end-to-end host to solve decrease in transmission rate caused by congestion in the application using multicast. In this proposed method, we've selected an overlay end-to-end host (OEH) for overcast transmission for each node, and the OEH can transmit duplicative packets. When the loss rate is more than the overcast threshold, the receivers of node in congestion are dropping from current layers and the OEH of lower nodes can request overcast transmission to OEH of non-congestion nodes for receiveing packets. In simulation results, it was known that the proposed method improves transmission rates over those of existing methods.

• International Commerce and Information Review
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• v.9 no.3
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• pp.273-284
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• 2007

New retailers, especially giant retailers, so called "mart" or "discounter" which introduced around 1996, when Korea's domestic retail market was opened to the world, have brought big transitions. Consequently, new comers like discounters and CVS drove out department stores, mom & pops and traditional retailers. Literatures showed two reverse opinions for the giant retailers; rising consumers' benefit, or dropping small retailers' businesses. This study have conducted to find the situation of market concentration in retail market, and to learn the new market condition in it. According to the study, in 2005, CR3's of Korea's whole retail industry was counted 12.8%, and CR5 of that was 13.9%. CR3 of discount store business was 39%, department stores' 55%, and TV home shopping businesses' was 75%. In addition to those results, indices growing worse. So, we can say this industry already get into the oligopolistic industrial organization. Generally, under monopolistic or oligopolistic market structure, consumers' benefit may shrink and businesses' surplus profit may jump. So, it means, it's good time to turn government's policy for the retail industry in Korea to fair competition policy instead of development policy.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.2 s.314
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• pp.11-18
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• 2007

Back propagation algorithm based on a gradient-decent method has been widely used to the training of a neural network. However, this algorithm have some problems such as dropping the minimum value in a local area according to an initial value and setting the number of units in a hidden layer when training the neural network. Accordingly, to solve the above-mentioned problems, this paper proposes a genetic algorithm using the training method of the neural network. Thus, the improved genetic algorithm using a new crossover and mutation method is proposed to discriminate 3 bit parity. Experiments confirm that the proposed system is effective for training speed after demonstrating for generation gap, the number of units in the hidden layer, and the number of individuals.

• International Journal of Industrial Entomology and Biomaterials
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• v.28 no.2
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• pp.66-70
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• 2014

In order to the feasibility of silk materials as protein delivery system, silk beads incorporated with bovine serum albumin (BSA) were prepared by dropping silk fibroin extract into dope solution composed of ethanol and dichloromethane. Structural and morphological characteristics of silk beads were examined using scanning electron microscopy (SEM), infrared spectrometry, and X-ray diffractometry. Swelling ratio of silk beads was also measured. Release behavior of prototypical protein, BSA, was studied by observing the electropheretic phenomenon and release profile. SEM showed that silk beads are spherical with porous interior structure. Infrared spectrometry and X-ray diffraction confirm that the silk beads have a ${\beta}$-sheet conformation. The swelling capability of silk beads increased with the incorporation of the protein. The protein was released from the beads with slow release following an initial burst release. Therefore, silk beads show promise as materials for encasing protein drugs to be delivered to targets in the human body.

• Journal of Aquaculture
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• v.17 no.4
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• pp.262-267
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• 2004

Physiological responses (oxygen consumption, ammonia excretion, hemoglobin, red blood cell and white blood cell) of cultured eel, Anguilla japonica to vibration stress were studied in an indoor experimental system. Vibration of 76-93 dB (V) from an electric vibrator was provided in 15-minute intervals during daytime (0800-1800) over a ten day period. Oxygen consumption before the beginning of the experiment (0 day) was 83.9 mg $O_2$$.$kg$^{-1}$ ㆍhr$^{-1}$ . After 1, 5 and 10 days of stress respiration rate decreased by 37.5, 53.7 and 70.5%, respectively. Ammonia excretion showed a similar pattern to that of oxygen consumption. Ammonia excretion decreased by 80.1 % following 10 days of vibration stress. Blood hemoglobin concentration also decreased at 1, 3 and 10th day were 29.4% on day 1,83.9% on day 3 and 87.9% by day 10, while red blood cell counts at day 1 and day 10th were 59.8% and 84.7% lower than initial counts, respectively. The white blood cell count increased by 191.2% at day 7, dropping to 41.5% at day 10. Physiological activity was reduced by 50% following 3.4 days of vibration stress.

• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.351-357
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• 1988

The electrochemical reduction of uranyl ion at the dropping mercury electrode and/or mercury microelectrode has been studied in propanediol-1,2-carbonate (PDC) by voltammetric techniques. The position of peak potentials, the nature of limiting currents, their dependency on temperature and on concentrations, reversibility of electrode reactions, and influence of addition of phenol are described. The influence of PDC in aqueous solution of uranyl ion was also described. The values of kinetic parameters, viz., transfer coefficient, formal constant for the electrode reactions bave been determined by Koutecky's method as extended by Meites and Israel. The values of ${\Delta}H,\;{\Delta}G\;and\;{\Delta}S$ have also been calculated.