• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.159-164
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• 2000

In SRM drive, The accuracy of the switching angles is dependent upon the resolution of the encoder and the sampling period of the microprocessor. As the speed increased, the amount of the switching angle deviation from the preset values is increased by the sampling period. Therefore, in this paper the low cost liner encoder for the practical and stable SRM drive is proposed and the control algorithm to provide the switching signals using the simple digital logic circuit is presented. and it is verified from the experiments that the proposed encoder and logic controller can be a powerful candidate for the practical low cost SRM drive.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.1
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• pp.109-118
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• 2016

The antioxidant potential of mistletoe (Viscum album L. var. coloratum Ohwi; VAL) extract in uncooked pork patties was evaluated. Three concentrations of VAL extract (0.1 [T1], 0.5% [T2] and 1.0% [T3]) along with 0.02% ascorbic acid as a positive control (V) were added to ground pork and pork patties were prepared. Incorporation of VAL extract decreased (p<0.05) the pH of the pork patties throughout the storage time and reduced (p<0.01) the thiobarbituric acid reactive substance values after day 14 of storage. Total plate counts of the VAL extract-treated samples and V-treated samples were also significantly lower (p<0.01) than that of the control (C) throughout the storage period. In addition, odor scores of the VAL extract-treated patties were lower than those of the C- or V-treated samples on 3rd day of the storage period. These results demonstrated that the VAL extract acts as a natural antioxidant in uncooked pork products.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.3
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• pp.295-301
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• 2005

The fine particles in the range of $30\~500nm$ are monitored at Hanyang University campus in Ansan using house made DMA (differential mobility analyzer) and commercial CPC (condensation particle counter, TSI inc.) in SMPS mode. The monitoring period is March 16th 2004 through May 7th, 2004. During the monitoring period, Aitken nuclei mode $(30\~100nm)$ particle concentration has a tendency of increase in the morning and evening hours. However, the accumulation mode $(100\~500nm)$ particle concentration stays rather stable than that of Aitken mode.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.65-65
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• 2000

For Video on Demand(VoD) servers, a design of an efficient scheduler is important to the support a large number of clients having various playback speeds and receiving rates. In this paper, we propose the scheduling algorithm to handle establishing deadlines and selection using the earliest deadline first. To establish deadlines and selections, the period of the receiving rates for each client is located between the over-max receiving rate and the over-playback rate. To avoid video starvation and the buffer overflow of each client, the proposed algorithm guarantees providing the admission control. Because of establishing deadlines and selection, period of each client receiving is between one over max receiving rate and one over play back rate. Using Virtual Buffer in server, scheduling load is reduced. The efficiency of the proposed algorithm is verified using a Petri Net_Based simulation tool, Exspect.

• Child Studies in Asia-Pacific Contexts
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• v.5 no.1
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• pp.39-49
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• 2015

Not all parents are skilled in scaffolding their young children's numeracy learning. The present study investigated the effectiveness of a parent training program in promoting Filipino young children's number sense via card game playing at home. Participants were 161 young children and their parents; families were of a relatively low socioeconomic status. During the 10-week intervention period, parents in the experimental group received training on how to use number game cards to help their children acquire various numeracy concepts; parents in the control group received no special instructions. Children in the experimental group showed greater improvements in their performance on six number sense tasks (namely numeral identification, object counting, rote counting, missing number, numerical magnitude comparison, and addition) over the intervention period than did children in the control group. Findings of the present study suggest that providing simple training to parents on strategies for fostering their young children's number sense at home is important for giving children a good early start in basic number knowledge.

• Journal of Navigation and Port Research
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• v.29 no.2
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• pp.151-157
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• 2005

During the period of every summer to early autumn seasons, ships have been wrecked or grounded from effect of a typhoon in the water areas around Korean Peninsula Typhoon Rusa killed more than 100 people in September 2002. Super Typhoon Maemi passed southeast of South Korea in September 12-13, 2003, with a strong gale blowing at a record 60 m/s and caused much ship groundings, collisions and sinkings over 3000 in dockyards, harbors and places of refuge. These are things that could have been prevented had there merely been prior warning. This study outlines the occurrence characteristics of maritime accidents caused by a typhoon in South Korea for the period from 1962 to 2002. The distribution of the accident records is also compared with the trajectories, winds, central pressures of typhoons, passed during the 1990-2003. It is shown that attack frequency of typhoon and number of marine accidents is the highest in August and the marine accidents due to typhoon have a close relation to the distribution of accumulated wind and pressure fields.

• Proceedings of the KIEE Conference
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• 1998.07g
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• pp.2237-2239
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• 1998

A limitation is assumed that In this paper, a generalized method is proposed to extract a period of a motion of on object. To detect a periodic motion, we put restrictions on a stationary camera and on a motion of an object. We ca derive the necessary and sufficient condition that an image sequence consists of the projection of the periodic motion by the affine transformation that is a reasonally good approach to the perspective projection. The difficulty of detecting its periodic motion is to select its have period in sequence and to define its width.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.9
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• pp.567-569
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• 2005

NARX(Nonlinear AutoRegressive with eXogenous input) neural network was used for prediction of nuclear reactor behavior which was influenced by control rods in short-term period and also by the concentration of xenon and boron in long-term period in load following operations. The developed model was designed to predict reactor power, xenon worth and axial offset with different burnup states when control rods and boron were adjusted in load following operations. Data of the Korea Next Generation PWR were collected by ONED94 code. The test results presented exhibit the capability of the NARX neural network model to capture the long term and short term dynamics of the reactor core and the developed model seems to be utilized as a handy tool for the use of a plant simulation.

• Journal of Electrical Engineering and Technology
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• v.3 no.2
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• pp.184-191
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• 2008

Electrical endurance is the critical characteristic of Magnetic contactors(MCs), which are widely used in such power equipment as elevators, cranes, and factory control rooms in order to close and open control circuits. Testing time, however, is not short in typical cases in which some method of reducing the testing period is required. This study shows the method of determining the stress level of electrical ALT(Accelerated Life Test) through optical temperature sensor and the relationship between 0.05 s and 0.1 s for on-time. The tool used for analyzing the test result is MINITAB. I will propose the method of determining the optimized stress level through optical temperature sensor, which will contribute to minimize the testing time and development period and also raise the product reliability.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.46.4-46
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• 2001

This paper presents a Five-Switch Converter (FSC) circuit that can operate like a full-bridge PWM converter for driving the DC motor in bidirectional. One of the main advantages of this circuit is to reduce the on-off switching number of power MOSFET. In stead of turning on-off simultaneously two of the four power MOSFET´s in a switching period, this circuit operates only one power MOSFET, while continuously leaving another two on and the other two off in the switching period. Consequently ...