• Journal of IKEEE
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• v.23 no.3
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• pp.878-882
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• 2019

XOR(exclusive-OR)-XNOR(exclusive NOR) circuit is a basic component of 4-2 compressor for high performance arithmetic operation. In this paper we propose an energy efficient XOR-XNOR circuit. The proposed circuit is reduced the internal parasitic capacitance in critical path and implemented with 8 transistors. The circuit produces a perfect output signals for all input combinations. Compared with the previous circuits, the proposed circuit has a 14.5% reduction in propagation delay time and a 1.7% increase in power consumption. Therefore, the proposed XOR-XNOR is reduced power-delay- product (PDP) by 13.1% and energy-delay-product (EDP) by 26.0%. The proposed circuits are implemented with standard CMOS 0.18um technology and verified through SPICE simulation with 1.8V supply voltage.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.181-194
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• 2002

Parasitism is a one-sided relationship between two organisms in which one benefits at the expense of the other. Parasitic dinoflagellates, particularly species of Amoebophrya, have long been thought to be a potential biological agent for controlling harmful algal bloom(HAB). Amoebophrya infections have been reported for over 40 species representing more than 24 dinoflagellate genera including a few toxic species. Parasitic dinoflagellates Amoebophrya spp. have a relatively simple life cycle consisting of an infective dispersal stage (dinospore), an intracellular growth stage(trophont), and an extracellular reproductive stage(vermiform). Biology of dinospores such as infectivity, survival, and ability to successfully infect host cells differs among dinoflagellate host-parasite systems. There are growing reports that Amoebophrya spp.(previously, collectively known as Amoebophrya ceratii) exhibit the strong host specificity and would be a species complex composed of several host-specific taxa, based on the marked differences in host-parasite biology, cross infection, and molecular genetic data. Dinoflagellates become reproductively incompetent and are eventually killed by the parasite once infected. During the infection cycle of the parasite, the infected host exhibits ecophysiologically different patterns from those of uninfected host in various ways. Photosynthetic performance in autotrophic dinoflagellates can be significantly altered following infection by parasitic dinoflagellate Amoebophrya, with the magnitude of the effects over the infection cycle of the parasite depending on the site of infection. Parasitism by the parasitic dinoflagellate Amoebophrya could have significant impacts on host behavior such as diel vertical migration. Parasitic dinoflagellates may not only stimulate rapid cycling of dissolved organic materials and/or trace metals but also would repackage the relatively large sized host biomass into a number of smaller dinospores, thereby leading to better retention of host's material and energy within the microbial loop. To better understand the roles of parasites in plankton ecology and harmful algal dynamics, further research on a variety of dinoflagellate host-parasite systems is needed.

• Journal of Nutrition and Health
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• v.14 no.4
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• pp.200-208
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• 1981

A survey was conducted from January 23 to 31 and February 14 to 18, 1981, in Whaseounggun, Kyunggj-do, to investigate the dietary and nutritionary status, and prevalence of parasitic infection of the fertile women, in an attempt to provide an integrative perspective on the rural family health programmes. The results are summarised as follows; The total number of fertile women, randomly selected, was 197 ; 21 women were in the latter half of pregnancy; 38 women, lactating, the remaning, non-pregnant. Average age of the subjects was 31.4 years; average number of children, 2.7; average number of abortion, 0.9; average family number in home, 5.5. The families had a mean income of \ 2,470,000 per fear. The majority, 83.8% of the families, were engaged in farming. 61.4% of the subjects had completed schooling 6 years or less. The mean energy intake of the lactating women was 73.4% of the recommended allowance, while that of non-pregnant and pregnant women reached 86.9 to 88.6% of the recommendation. In the average diet of the subjects, carbohydrates contribute 74.6 to 81.7% of the total energy intake; protein 11.3 to 11.9%; fat 7.0 to 13.9%. Protein intake of non-pregnant, pregnant, and lactating women met 72.6%, 60.8%, and 65.2% of allowance, respectively; and those proteins were mainly derived from vegetable sources. The subjects ingested less than one-half of the allowances for iron, calcium, vitamin A, and riboflabin ; in contrast, thiamin and ascorbic acid levels were adequate or fairly acceptable. There were significant correlations of meal balance and food diversity scores to the mean intake levels of protein, calcium, iron, vitamin A, thiamin, and riboflavin. Only 10% of the pregnant women and 11.4% of non-pregnant and lactating women reached the acceptable level of hemoglobin. Positive prevalence of parasitic infection was found among about one-third of the subjects, 30.3% of women. Hematologic findings had no significant correlation to parasitic infection.

• Journal of Nutrition and Health
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• v.14 no.4
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• pp.190-199
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• 1981

A survey of nutrition and incidence of parasites was conducted from January 23 to 31 and February 14 to 18, 1981, to determine the nutritional status of young children under the age of 6 years, in one of the rural family health project areas: Whaseoung-gun, Kyunggi-do, Korea. This study covered a total of 233 children. The results are summarised as follows: Approximately one-half of these families had an annual income between \1,000,000 and \2,500,000. Nearly 84% of the households were involved in farming. Energy intake of children met 70.6% of the requirement: carhohydrates provided 77%, protein provided 11%, and fat provided 12% of the total energy intake. Low intake of iron; calcium; and vitamins, excluding thiamin, was also found. Mean hemoglobin value was $10.6{\pm}1.0gm/100ml.;\;42%$ of subjects were categorized as low group, 22% were in the deficient group, and only 36% were at an acceptable level as indicated by O'Neal. Thus, 22% of the subjects were proven to be anemic by the hemoglobin criteria. Mean hematocrit value was $30.1{\pm}2.8%$, and 80 of 208 children, or 38.4% of subjects, were below 30% of the standard established by O'Neal. The positive prevalence of parasitic infection was 20% , significantly higher than that observed in the Yowido compound (5.5%) in 1980. Hematologic findings had no significant correlation to parasitic infection. The majority, 95.2% of the subjects, met or surpassed 90% of the KlST's standard of height:whtile 28. 6% of the subjects were below 90% of the KIST's standard of weight. The ratio of weight to height for boys 4 to 6 years old was 15.8 to 17.5, in contrast to 16.3 to 16.9 for boys of KHDI project areas, and also in contrast to 17.7 to 17.9 for boys of the same age group from the Yowido apartment compound in Seoul. According to the results of the assessments, the authors found a clear difference in growth values, hematologic findings and dietary patterns between rural areas and advantaged urban areas of Seoul. Our results suggest the need to develop the nutrition and parasite control training of village women for better nutritional care of their young children.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.6
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• pp.539-545
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• 2012

Due to merits cost and efficiency, the transformer-less type photovoltaic (PV) inverters have been popularized in the solar market. However, the leakage current flowing through a parasitic capacitor between PV array and ground can cause adverse effect in the transformer-less PV system. In this paper, a bi-directional PV inverter with high efficiency and low noise is proposed for the PV system with an energy storage device. The proposed inverter is a transformer-less type and performs the bi-directional power control between dc sources and grid with high efficiency. In addition, the proposed inverter can suppress the leakage current and obtain low noise characteristic. Finally, 3-kW prototype was implemented to confirm validity of the proposed inverter.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.3
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• pp.147-152
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• 2019

With the recent emphasis on the importance of energy conservation, studies on high-efficiency elevator systems are being continuously conducted. Therefore, pulse width modulation converters are commonly used in traction drives on elevator systems. Wide bandgap devices have been increasingly commercialized, and their application to power conversion systems, such as renewable and energy storage system, has been gradually increasing. In this study, a SiC inverter for an elevator traction drive is investigated. In particular, an inverter is designed to minimize stray and parasitic inductance. Input and output filters are designed by considering switching frequency. The designed SiC inverter reduces volume by approximately 32% compared with that of a Si inverter, and power converter efficiency is over 98.8%.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_1
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• pp.985-991
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• 2023

This study proposes a solution to the voltage drop in electric vehicle chargers, due to the parasitic resistance and inductance of power cables when the chargers are separated by large distances. A method using multi-level electric vehicle chargers that can output power in stages, without installing an additional energy supply source such as a reactive power compensator or an energy storage system, is proposed. The voltage drop over the power cables, to optimize the charging scheduling, is derived. The obtained voltage drop equation is used to formulate the constraints of the optimization process. To validate the effectiveness of the obtained results, an optimal charging scheduling is performed for each period in a case study based on the assumed charging demands of three connected chargers. From the calculations, the proposed method was found to generate an annual profit of $20,800 for a $12,500 increase in installation costs.

• Journal of Advanced Navigation Technology
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• v.18 no.1
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• pp.56-66
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• 2014

In this paper, the solar cell need the characteristic interpreting because the solar cell changes greatly according to the isolation, temperature and load in the photovoltaic development. Moreover, to get many energy in photovoltaic development need the position tracking of the sun according to the environment change and it is necessary to control the output of solar cells up to the time. Simulation and composed microprocessor and sensor chip an power conversion system with boost converter to experiment results are performed to prove the analysis of the converter operation, and to show the possibility of energy harvesting and photovoltaic development need the position tracking small capacitance, the boost rate of boost converter was similar to 167 percent.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.2
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• pp.64-72
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• 2001

In this paper, forward Zero Voltage Switching Multi Resonant Converter(ZVS MRC) for non-contact charging energy transmission is reposed. The forward ZVS MRC is effective in adsorbing parasitic element as well as minimizing the switching loss. That can accommodate very high frequency. So forward ZVC MRC is applied to non-contact charging energy transmission. Used converter has saperatable transformer and synchronous rectifiers. Coupling coefficient(k), leakage inductance, coupling inductance and resonant frequency are observed for the air gap. By using the observed value, this circuit is designed and implemented. This proposed circuit is simulated by the PSPICE and experimented. The voltage stress of a main switch and the output power of the converter are measured. This paper show that is compatible for non-contact charging energy transmission.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.344-348
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• 2009

One-dimensional modeling was carried-out to predict the capacity loss of a lithium-ion polymer battery during cycling. The model not only accounted for electrochemical kinetics and ionic mass transfer in a battery cell, but also considered the parasitic reaction inducing the capacity loss. In order to validate the modeling, modeling results were compared with the measurement data of the cycling behaviors of the lithium-ion polymer batteries having nominal capacity of 5Ah from LG Chem. The cycling was performed under the protocol of the constant current discharge and the constant current and constant voltage charge. The discharge rate of 1C was used. The range of state of charge was between 1 and 0.2. The voltage was kept constant at 4.2 V until the charge current tapered to 50 mA. The retention capacity of the battery was measured with 1C and 5C discharge rates before the beginning of cycling and after every 100 cycles of cycling. The modeling results were in good agreement with the measurement data.