• Title/Summary/Keyword: energy level

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Self-Consistent Calculation of Electronic Subband Structure at GaInAs/InP Heterojunction (Self-Consistent 방법에 의한 GaInAs/InP 이종접합에서의 전자 부밴드 구조계산)

  • Kong, Joon-Jin;Park, Seong-Ho;Kim, Choon-Won;Han, Baik-Hyung;,
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.1
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    • pp.38-47
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    • 1989
  • Calculated results for subband structures of electrons in GaInAs/InP hegerojunctions are presented, and their sensitivity to two parameters background impurity concentrations in the GaInAs, heterojunction barrier height-is examined. Energy levels, Fermi level and population of the ground energy level are increased with background impurity concentrations. The difference of the ground and first-excited energy levels is also increased with the increase of barrier height. However, the difference of the energy levels is almost invariable with barier height. But, population of the ground energy level decreases, but that of the first-excited energy level shows a slight increase.

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An Ecological Analysis of Iron Status of Middle School Students in Seoul (중학생의 철분 영양 상태에 영향을 미치는 생태학적 변인 분석)

  • 최주현
    • Journal of Nutrition and Health
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    • v.30 no.8
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    • pp.960-975
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    • 1997
  • This study was carried out to evaluate the iron nutrition status of 212 middle school students(106 males and 106 females) residing in Seoul(13-14 years old ) using eating patterns and a measurement of anthropometrical determination and hematological indices. Fasting blood samples were taken from all subjects, serum iron (SI) and total iron binding capacity(TIBC) concentrations were measured, and transferrin saturation(TS) levels were calculated. Iron and other nutrient intakes were estimated by a semi-quantitative frequency questionnaire. The level of TS(%) which was calculated with TIBC and SI in females(20.4$\mu\textrm{g}$/dl) was significantly lower(p<0.050 than that of males (27.4$\mu\textrm{g}$/㎗). The prevalence of iron deficiency was found to be 36.7% when defined by TS(%) (<05%). Mean daily intake of total iron in the study subjects was 14mg and heme iron intake was 5.4mg(38.1%) . There was a significant negative correlation between the level of SI and the income level and a positive correlation with the level of TIBC and the income level. TIBC had a positive correlation with the anthropometric variables(Ht, Wt, BMI, RI and PIBW). SI and TS had a negative correlation with body fat percentage. There was a positive correlation between energy intake and TIBC only among females. The logistic regression analysis revealed that income level, body fat percentage , weight and energy intake were major determinants of low SI levels. Among the determinants of abnormal TIBC levels were weight , height, income level and energy intake. Finally , among those of low TS% were iron and energy intake and income level. These observations suggest that physical status, body fat percentage energy and iron intakes and income level are risk factors for iron-deficiency anemia among the middle school students in Seoul.

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Instruction-Level Power Estimator for Sensor Networks

  • Joe, Hyun-Woo;Park, Jae-Bok;Lim, Chae-Deok;Woo, Duk-Kyun;Kim, Hyung-Shin
    • ETRI Journal
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    • v.30 no.1
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    • pp.47-58
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    • 2008
  • In sensor networks, analyzing power consumption before actual deployment is crucial for maximizing service lifetime. This paper proposes an instruction-level power estimator (IPEN) for sensor networks. IPEN is an accurate and fine grain power estimation tool, using an instruction-level simulator. It is independent of the operating system, so many different kinds of sensor node software can be simulated for estimation. We have developed the power model of a Micaz-compatible mote. The power consumption of the ATmega128L microcontroller is modeled with the base energy cost and the instruction overheads. The CC2420 communication component and other peripherals are modeled according to their operation states. The energy consumption estimation module profiles peripheral accesses and function calls while an application is running. IPEN has shown excellent power estimation accuracy, with less than 5% estimation error compared to real sensor network implementation. With IPEN's high precision instruction-level energy prediction, users can accurately estimate a sensor network's energy consumption and achieve fine-grained optimization of their software.

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Characteristics of Electric-Power Use in Residential Building by Family Composition and Their Income Level (거주자 구성유형 및 소득수준에 따른 주거용 건물 내 전력소비성향)

  • Seo, Hyun-Cheol;Hong, Won-Hwa;Nam, Gyeong-Mok
    • Journal of the Korean housing association
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    • v.23 no.6
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    • pp.31-38
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    • 2012
  • In this paper, we draws tendency of the electricity consumption in residential buildings according to inhabitants Composition types and the level of incomes. it is necessary to reduce energy cost and keep energy security through the electricity demand forecasting and management technology. Progressive social change such as increases of single household, the aging of society, increases in the income level will replace the existing residential electricity demand pattern. However, Only with conventional methods that using only the energy consumption per-unit area are based on Energy final consumption data can not respond to those social and environmental change. To develop electricity demand estimation model that can cope flexibly to changes in the social and environmental, In this paper researches propensity of electricity consumption according to the type of residents configuration, the level of income. First, we typed form of inhabitants in residential that existed in Korea. after that we calculated hourly electricity consumption for each type through National Time-Use Survey performed at the National Statistical Office with considering overlapping behavior. Household appliances and retention standards according to income level is also considered.

Effect of FSH-P Dose and Energy Level on Normal Embryo Production in Hanwoo (한우에 있어서 FSH-P 투여량과 에너지수준이 정상수정란의 생산에 미치는 영향)

  • 임석기;전기준;우제석;장선식;박준철;정종원;윤상보
    • Journal of Embryo Transfer
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    • v.12 no.3
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    • pp.301-306
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    • 1997
  • The present study was carried out to investigate effect of FSH -P dose and energy level on normal embryo production after superovulation in Hanwoo. The results obtained were as follows ; 1. There was a significant effect of dose of FSH-P on normal embryo production in Hanwoo(P$\pm$5.9), 40(4.9i5.7), 50mg(2.2$\pm$2.6). 2. The plasma P$_4$ levels on the first treatment day were higher group( >4ng /ml) than lower group( <=4ng /ml), produced significicantly(P<0.05) higher number of normal embryos. 3. There was a significant effect of energy level on normal embryo production in Hanwoo(P$\pm$6.0), number of normal embryos were higher than TDN 70%(5.1$\pm$6.5) and TDN 130%(4.4$\pm$2.6) 4. The donor returned to normal estrus after superovulation were 44.8, 28.4 and 29.9 days by TDN 70, 100 and 130%, respectively.

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Multi-unit Level 3 probabilistic safety assessment: Approaches and their application to a six-unit nuclear power plant site

  • Kim, Sung-yeop;Jung, Yong Hun;Han, Sang Hoon;Han, Seok-Jung;Lim, Ho-Gon
    • Nuclear Engineering and Technology
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    • v.50 no.8
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    • pp.1246-1254
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    • 2018
  • The importance of performing Level 3 probabilistic safety assessments (PSA) along with a general interest in assessing multi-unit risk has been sharply increasing after the Fukushima Daiichi nuclear power plant (NPP) accident. However, relatively few studies on multi-unit Level 3 PSA have been performed to date, reflecting limited scenarios of multi-unit accidents with higher priority. The major difficulty to carry out a multi-unit Level 3 PSA lies in the exponentially increasing number of multi-unit accident combinations, as different source terms can be released from each NPP unit; indeed, building consequence models for the astronomical number of accident scenarios is simply impractical. In this study, a new approach has been developed that employs the look-up table method to cover every multi-unit accident scenario. Consequence results for each scenario can be found on the table, established with a practical amount of effort, and can be matched to the frequency of the scenario. Preliminary application to a six-unit NPP site was carried out, where it was found that the difference between full-coverage and cut-off cases could be considerably high and therefore influence the total risk. Additional studies should be performed to fine tune the details and overcome the limitations of the approach.

Energy Consumption and Exercise Effect of University Students During Automatic Stepper Exercise

  • MOON, Hwang-woon;CHOI, Youn-Jin
    • The Korean Journal of Food & Health Convergence
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    • v.7 no.6
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    • pp.17-24
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    • 2021
  • This study investigates the exercise-physiological changes in stages through the movement of the automatic stepper and to analyze the usefulness of the automatic stepper. For 18 male university students, out of 10 levels, 5 level and 10 level of automatic stepper exercise were performed. At each 10, 20, 30 minutes during exercise, 5 and 10 minutes after exercise stop the subjects were examined to analyze the changes in energy consumption after minutes, respiratory exchange rate, heart rate, oxygen consumption per body weight, METs, cumulative energy consumption, and lactic acid to verify the usefulness of the automatic stepper. The mean and standard deviation were calculated using the SPSS, and one-way ANOVA with repeated measure was performed to verify the difference in the mean between time periods. The LSD method was used for the post-hoc test, and the significance level was set to α = .05. There were no significant changes in both 5 and 10 level, but the cumulative energy consumption over time increased significantly. In addition, as a low-intensity exercise intensity is shown, a low increase in lactic acid indicated a safe exercise level. In future studies, in-depth studies of various variables through regular exercise programs are needed for those who need safe exercise.

Ideal Energy Level Alignment Technology for Phosphorescent OLEDs

  • Kim, Sun-Young;Kwon, Jang-Hyuk
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1414-1417
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    • 2008
  • Using a $Ir(ppy)_3$ doped in the TCTA:$Bepp_2$ mixed host and N- and P-doped in TCTA:$Bepp_2$ charge transport layers, an ideal energy level alignment technology is developed. A very low roll-off current efficiency of 7.4 % at a luminance of $10,000\;cd/m^2$ with this technology is demonstrated in green phosphorescent OLEDs.

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A Supercapacitor Remaining Energy Control Method for Smoothing a Fluctuating Renewable Energy Power

  • Lee, Wujong;Cha, Hanju
    • Journal of Electrical Engineering and Technology
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    • v.10 no.1
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    • pp.146-154
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    • 2015
  • This paper proposes a control method for maintaining the energy level for a supercapacitor energy storage system coupled with a wind generator to stabilize wind power output. Although wind power is green and clean energy source, disadvantage of the renewable energy output power is fluctuation. In order to mitigate the fluctuating output power, supercapacitor energy storage system (SCESS) and wind power simulator is developed. A remaining energy supercapacitor (RESC) control is introduced and analyzed to smooth for short-term fluctuating power and maintain the supercapacitor voltage within the designed operating range in the steady as well as transient state. When the average and fluctuating component of power increases instantaneously, the RESC compensates fluctuating power and the variation of fluctuating power is reduced 100% to 30% at 5kW power. Furthermore, supercapacitor voltage is maintained within the operating voltage range and near 50% of total energy. Feasibility of SCESS with RESC control is verified through simulation and experiment.

An Index-Based Context-Aware Energy Management System in Ubiquitous Smart Space (유비쿼터스 지능 공간에서의 지수 기반 상황인지 에너지경영 시스템)

  • Kwon, Ohyung;Lee, Yonnim
    • Knowledge Management Research
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    • v.9 no.4
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    • pp.51-63
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    • 2008
  • Effective energy consumption now becomes one of the area of knowledge management which potentially gives global impact. It is considerable for the energy management to optimize the usage of energy, rather than decreasing energy consumption at any cases. To resolve these challenges, an intelligent and personalized system which helps the individuals control their own behaviors in an optimal and timely manner is needed. So far, however, since the legacy energy management systems are nation-wide or organizational, individual-level energy management is nearly impossible. Moreover, most estimating methods of energy consumption are based on forecasting techniques which tend to risky or analysis models which may not be provided in a timely manner. Hence, the purpose of this paper is to propose a novel individual-level energy management system which aims to realize timely and personalized energy management based on context-aware computing approach. To do so, an index model for energy consumption is proposed with a corresponding service framework.

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