• International Journal of Aeronautical and Space Sciences
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• v.16 no.4
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• pp.537-547
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• 2015

A Monte Carlo (MC) simulation was conducted to predict the reliability of a newly developed pyrotechnic pin puller. The reliability model is based on the stress-strength interference model that states that failure occurs if the stress exceeds the strength. In this study, the stress is considered to be the energy consumed by movement of a pin shaft, and the strength is considered to be the energy generated by pyrotechnic combustion for driving the pin shaft. Failure of the pin puller can thus be defined as the consumed energy being greater than the generated energy. These energies were calculated using a performance model formulated in the previous study of the present authors. The MC method was used to synthesize the probability densities of the two energies and evaluate the reliability of the pin puller. From a probabilistic perspective, the calculated reliability was compared to a deterministic safety factor. A sensitivity analysis was also conducted to determine which design parameters most affect the reliability.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.649-651
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• 2016

Wireless Sensor Network(WSN) consists of spatially distributed sensors to monitor physical conditions, such as temperature, light and motion, and to pass their data through the network to a base station. Each battery equipped node is consumed to pass their data to their neighbors. We are gathering the amount of energy that was consumed to gather data and to pass it This paper describes processes of energy consumption of WSN in Matlab.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.1
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• pp.46-50
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• 1983

A reverse voltage commutating thyristor chopper was described. The chopper consists of commutating capacitor charging circuit and commutating thyristor. By superimposing the charged voltage on capacitor to load voltage. Powerful reverse voltage could be induced on main thyristor cathode. And in that wise the chopping action was performed without all the reactors of the proposed circuit. An energy recovery circuit was employed in the chopper circuit for recovering the energy that was consumed in main thyristor commutation. The operating principles of the chopper circuit was analyzed and experimental results were as following. I) All reactors were eliminated. ii) By applying energy recovery circuit to the chopper, 67% of the consumed energy was recovered to source. iii) Turn off time of the proposed chopper was derived as T=RC ln2.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.717-722
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• 2007

Most of DC 1500V electric railway substations have adopted diode rectifiers to supply stable DC power. However, the diode rectifiers operate in the first quadrant of the voltage-current plane and thus need regenerative inverters which transfer the surplus regenerative power caused by regenerative braking of electric train sets into the grid. In order to select the proper capacity and installation position of regenerative inverter, it needs to investigate the consumed and regenerative energy of the electric traction substations in advance. This paper presents an analysis of regenerative energy in two substations operating in Seoul Seolleung and Kwangju Yangdong substations. DC line voltage and feeder currents are measured for a day to calculate consumed and regenerative power far four feeders. We calculated an amount of regenerative energy consumed in other feeders and estimated the cost reduction in energy consumption due to the reuse of regenerative energy

• Nutrition Research and Practice
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• v.11 no.2
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• pp.155-163
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• 2017

BACKGROUND/OBJECTIVES: The commercial foodservice industry in Korea has shown rapid growth recently. This study examined Korean adults' consumption of commercially-prepared meals based on where the food was prepared. SUBJECTS/METHODS: Data from a 24-hour dietary recall of the 2001 and 2011 Korea National Health and Nutrition Examination Surveys were analyzed. A total of 10,539 subjects (n = 6,152 in 2001; n = 4,387 in 2011) aged 19-64 years were included for analysis. Commercially-prepared meals were classified into four food source groups based on where the food was prepared: Korean restaurants, Chinese/Western/Japanese restaurants, fast-food restaurants, and retail stores. Subjects' energy intake, including the amount and proportion of calories, was examined for each food source. The analysis was also conducted by gender for age-stratified groups: 19-29, 30-49, and 50-64 years old. RESULTS: Korean adults' energy intake from commercially-prepared meals increased in the amount of calories (551 kcal to 635 kcal, P < 0.01), but not in the proportion of daily calories (27% to 28%) from 2001 to 2011. The most frequent food source of commercially-prepared meals was Korean restaurants in both years. The amount and proportion of calories from retail stores increased from 83 kcal to 143 kcal (P < 0.001) and from 4% to 7% (P < 0.001), respectively, during the same period. Males aged 30-49 years (34%) and females aged 19-29 years (35%) consumed the highest proportion of daily calories from commercially-prepared meals in 2011. CONCLUSIONS: Korean adults consumed about one-fourth of their energy intake from commercially-prepared meals. In particular, males aged 30-49 years and females aged 19-29 years consumed more than one-third of their energy intake from commercially-prepared meals. Korean restaurants played a significant role in Korean adults' energy intake. Retail stores increased influence on Korean adults' energy intake. These results could be useful for developing health promotion policies and programs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.1
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• pp.1-11
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• 2013

Reducing the energy that consumed by tag is a key requirement for the wider acceptance of the active RFID systems that use battery constrained tags. When the reader is not interrogating, the active RFID standard protocols try to reduce energy consumption of tags by using sleep mode. On sleep mode tags is active by receiving a specific signals from reader, until tag receive a sleep mode command from the reader, a tag waste energy for remaining in RX mode. Overhearing is a state of a tag in which it wastes energy for maintaining active RX state while there is no frame destined to it. According to our analysis, the amount of energy consumed by a tag due to overhearing is several time larger than that consumed by the effective communication. We propose RANO(Reservation Aloha for No Overhearing) that is designed to inform a tag of its effective communication intervals to eliminate overhearing problem in active RFID communication. The performance of the proposed protocol was evaluated through the real world by changing the number of tags and size of data. The result of an experiment, the proposed protocol performed saving about 22 times less than the standard protocol did.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.10
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• pp.506-510
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• 2002

In this paper, we study on the mutual characteristics between transmitting efficiency of pulse energy and wall plug consumed power of non-thermal Plasma for removing environmental pollutive gas of coal plant. To obtain high pulse energy of our system, we used MPC(magnetic pulse compressor) of power switch and tested their characteristics by adjusting electrode length of reactor and charging voltage in capacitor. As a result, we obtained consumed power of wall plug and a compressed pulse of voltage 110kV, rising time 500ns. Impedance of load on increasing electrode length was decreased, but electrical efficiency was increased. These results indicate we can control critical voltage of pulse corona and electrical efficiency of economic cost in power plant.

• Nutrition Research and Practice
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• v.13 no.1
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• pp.70-75
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• 2019

BACKGROUND/OBJECTIVES: Association between the consumption of sugar-sweetened beverages (SSBs) and obesity is universally a controversial issue. This study was undertaken to examine the beverage consumption pattern of Korean adolescents. SUBJECTS/METHODS: Data was collected from the 2016 Korea Youth Risk Behavior Survey involving 65,528 adolescent respondents. A list of the most frequently consumed beverages was analyzed, and the consumption frequency of carbonated beverages, SSBs, and energy drinks during the past seven-days was assessed. The main reasons for the adolescents to consume the beverages were also determined. RESULTS: The beverage preference of adolescents were carbonated beverages (31.0%), 'fruit and vegetable beverages (17.7%)', 'milk (13.6%)', and 'coffee (12.7%)'. Carbonated beverages and SSBs were consumed more than three times a week by 27.1% and 41.1% of the respondents, respectively. About 86.2% of adolescents did not take of any energy drinks during the last seven-days. Taste was the most common reason that adolescents considered when choosing a drink. Carbonated beverages consumed more frequently by boys than girls, and high school students drank coffee more frequently than middle school students. CONCLUSIONS: Boys had a higher preference for unhealthy beverages than girls, whereas consumption of high-caffeine drinks was greater amongst high-school students than middle school students.

• New & Renewable Energy
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• v.7 no.1
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• pp.29-35
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• 2011

The waste treatment fee and energy production effect of Wonju city RDF plant, the first RDF manufacturing plant in Korea, were investigated in the study. All plant operation data, like total weight of received wastes, produced RDF and separated rejects in processes were fully recorded for mass balance calculation of the plant in 2009. Also all consumed oil and electricity were recorded for energy balance calculation. The results showed that the waste treatment fee not including the RDF sales price of 25,000 won/ton-RDF was 116,573 won/ton-MSW and it went down to 105,298 won when included the RDF price. Produced RDF was 40.2% of total received waste in weight. Three components analysis by mass balance calculation of total received waste showed that Wonju city's MSW was 32.4% of combustible, 37.5% of water and 30.1% of incombustible respectively. Energy effect was found that total amount of produced energy was about 4 times more than that of consumed energy.

• Journal of Korea Spatial Information System Society
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• v.12 no.1
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• pp.1-9
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• 2010

Recently, wireless sensor networks(WSNs) technology has been considered as one of the most critical issues in the ubiquitous computing age. The sensor nodes have limited battery power, so they should consume low energy through their operation for the long-lasting lifetime. Therefore, it is essential to use energy efficient routing protocol. For this, we propose a location-based energy-efficient routing protocol which constructs the energy efficient route by considering the quantity of Energy consumed. In addition, we propose a route reconstruction algorithm to handle the disconnection of message transmission. Finally, we show from performance analysis using TOSSIM that our protocol outperforms the existing location based routing protocols in terms of energy efficiency.