• Title/Summary/Keyword: 에너지예측

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A Case Study on the Exogenous Factors affecting Extra-large Egg Production in a Layer Farm in Korea (산란계 사육농장 특란 생산에 미치는 외부 요인 분석을 위한 사례 연구)

  • Lee, Hyun-Chang;Jang, Woo-Whan
    • Korean Journal of Poultry Science
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    • v.41 no.2
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    • pp.99-104
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    • 2014
  • The objective of this study is to analyze the production of extra-large egg and assess the impacts of exogenous factors in feeding the layer chicken. The main results of this study are as follows; First, feeding rations on the basics of statistics, internal maximum and minimum temperature and, the age at first egg affect the production of extra-large egg. Second, implicating the standardized coefficients from the conclusion of regression model estimating suggest that the amount of feed has the greatest impact on production followed by the age at first egg. Third, by using the elasticity of output and the volatility in the production, the result suggest that among the independent variable factors in the external volatility, the biggest one goes to feed ration, and the age at first egg follows. In order to control the production volatility in the extra-large egg production of the farms, it is necessary to manage an efficient feeding based on feed ration, age at first egg and, the maximum and minimum temperature inside the farm. Taken together, the results demonstrates that it should be concentrated by controlling the exogenous factors affecting extra large egg production and the management system construct, to increase extra-large egg production and the income of farmers at the same time.

Infrared Characteristics of Some Flash Light Sources (섬광의 적외선 특성 연구)

  • Lim, Sang-Yeon;Park, Seung-Man
    • Korean Journal of Optics and Photonics
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    • v.27 no.1
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    • pp.18-24
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    • 2016
  • To effectively utilize a flash and predict its effects on an infrared device, it is essential to know the infrared characteristics of the flash source. In this paper, a study of the IR characteristics of flash light sources is carried out. The IR characteristics of three flash sources, of which two are combustive and the other is explosive, are measured with an IR characteristic measurement system over the middle- and long-wavelength infrared ranges. From the measurements, the radiances over the two IR ranges and the radiative temperatures of the flashes are extracted. The IR radiance of flash A is found to be the strongest among the three, followed by those of sources C and B. It is also shown that the IR radiance of flash A is about 10 times stronger than that of flash B, even though these two sources are the same type of flash with the same powder. This means that the IR radiance intensity of a combustive flash source depends only on the amount of powder, not on the characteristics of the powder. From the measured radiance over MWIR and LWIR ranges for each flashes, the radiative temperatures of the flashes are extracted by fitting the measured data to blackbody radiance. The best-fit radiative temperatures (equivalent to black-body temperatures) of the three flash sources A, B, and C are 3300, 1120, and 1640 K respectively. From the radiance measurements and radiative temperatures of the three flash sources, it is shown that a combustive source radiates more IR energy than an explosive one; this mean, in turn, that the effects of a combustive flash on an IR device are more profound than those of an explosive flash source. The measured IR radiances and radiative temperatures of the flash sources in this study can be used to estimate the effects of flashes on various IR devices, and play a critical role for the modeling and simulation of the effects of a flash source on various IR devices.

Study of the ENC reduction for mobile platform (모바일 플랫폼을 위한 전자해도 소형화 연구)

  • 심우성;박재민;서상현
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2003.05a
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    • pp.181-186
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    • 2003
  • The satellite navigation system is widely used for identifying a user's position regardless of weather or geographic conditions and also make effect on new technology of marine LBS(Location Based Service), which has the technology of geographic information such as the ENC. Generally, there are conceivable systems of marine LBS such as ECDIS, or ECS that use the ENC itself with powerful processor in installed type on ships bridge. Since the ENC is relatively heavy structure with dummy format for data transfer between different systems, we should reduce the ENC to small and compact size in order to use it in mobile platform. In this paper, we assumed that the mobile system like PDA, or Webpad can be used for small capability of mobile platform. However, the ENC should be updated periodically by update profile data produced by HO. If we would reduce the ENC without a consideration of update, we could not get newly updated data furthermore. As summary, we studied considerations for ENC reduction with update capability. It will make the ENC be useful in many mobile platforms for various applications.

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Measurement of the Quantity of Hydrogen Peroxide Produced in the Ultrasound-irradiated Aqueous Solution of Organic Compounds (초음파를 조사(照射)한 유기화합물 수용액 속에서의 과산화수소 생성량의 측정)

  • Mo, Se-Young;Chang, Hong-Ki;Lee, Kyung-Jae;Jang, Gun-Eik;Sohn, Jong-Ryeul
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.1
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    • pp.61-71
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    • 2000
  • When irradiate the power ultrasound into the aqueous solutions, water vapor is decomposed by the heat of very high temperature in the cavitation bubble to produce OH (hydroxyl radical) and H (hydrogen radical), and these radicals play a role in decomposing the substances in aqueous solution by oxidation and/or reduction, and in producing the hydrogen peroxide. Accordingly it is possible to predict that the quantity of hydrogen peroxide produced may correlate with the sonolysis mechanism of the substance in aqueous solution. Thus to confirm this prediction, the quantities of hydrogen peroxide produced from each of the air saturated distilled water and three aqueous solutions of TCE, benzene, and 2,4-DCP that are prepared by dissolving them into distilled water are measured. As a result, it showed that the quantity of hydrogen peroxide produced from the distilled water and three aqueous solutions are increased in order of distilled water>TCE solution>2,4-DCP solution>benzene solution, and decrease with decrease in concentration of organic substance, which coincide with the sonolysis mechanisms reported that TCE in aqueous solution is decomposed directly by the pyrolysis in and around the cavitation bubbles when its concentration is high and by the radical reaction when low, however, benzene and 2,4-DCP are decomposed not only by the pyrolysis but also by the radical reactions. Effects of such experimental parameters as the acoustic frequency and power and as the concentration showed that the higher the acoustic frequency and the lower the acoustic power, the less the quantity of hydrogen peroxide was produced. This result coincide with the theory of ultrasound for the relation between the cavitation that is the energy source of the power ultrasound in aqueous solution and these experimental parameters.

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The Association between Bone Mineral Density, Bone Turnover Markers, and Nutrient Intake in Pre- and Postmenopausal Women (폐경 전.후 여성의 골밀도 및 골대사 지표에 영향을 미치는 요인)

  • Park, Ji-Youn;Choi, Mi-Youn;Lee, Seon-Heui;Choi, Yoon-Ho;Park, Yoo-Kyoung
    • Journal of Nutrition and Health
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    • v.44 no.1
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    • pp.29-40
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    • 2011
  • The purpose of this study was to examine the association among bone mineral density (BMD), biochemical bone markers, nutrients, and salt intake in premenopausal and postmenopausal women. We evaluated 431 subjects who visited a health promotion center of a university hospital between January 2008 and July 2009. We excluded those who were taking medications or who had an endocrine disorder affecting osteoporosis. The subjects were divided into premenopausal (n = 283) and postmenopausal (n = 143) women. We evaluated the correlation among BMD of the lumbar spine, femoral neck, and total femoral, as well as biochemical bone markers, hormone, serum profiles, general characteristics, nutrient intakes, and food intake frequencies. From a stepwise multiple regression analysis, lumbar spine BMD was positively correlated with weight (p < 0.001) and negatively correlated with osteocalcin (OC)(p < 0.001), Femoral neck BMD was positively correlated with weight (p < 0.001) and negatively correlated with C-telopeptide (CTx) and alkaline phosphatase (ALP)(p < 0.001, p < 0.05). In premenopausal women, femoral total BMD was positively correlated with BMI (p < 0.001) and negatively correlated with CTx (p < 0.001). In postmenopausal women, lumbar spine BMD was positively correlated with calcium intake (p < 0.01) and negatively correlated with sodium intake (p < 0.01). Femoral neck and femoral total BMD were both positively correlated with weight (p < 0.001), and femoral neck BMD was negatively correlated with age and ALP (p < 0.001, p < 0.05). Femoral total BMD was negatively correlated with age and OC (p < 0.001, p < 0.01). These results suggest that reducing sodium intake may play an important role delaying bone resorption and preventing a decrease in BMD.

Development of Strategies to Improve Water Quality of the Yeongsan River in Connection with Adaptation to Climate Change (기후변화의 적응과 연계한 영산강 수질개선대책 개발)

  • Yong Woon Lee;Won Mo Yang;Gwang Duck Song;Yong Uk Ryu;Hak Young Lee
    • Korean Journal of Ecology and Environment
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    • v.56 no.3
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    • pp.187-195
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    • 2023
  • Almost all of the water from agricultural dams located to the upper of the Yeongsan river is supplied as irrigation water for farmland and thus is not discharged to the main stream of the river. Also, most of the irrigation water does not return to the river after use, adding to the lack of flow in the main stream. As a result, the water quality and aquatic health of the river have become the poorest among the four major rivers in Korea. Therefore, in this study, several strategies for water quality improvement of the river were developed considering pollution reduction and flow rate increase, and their effect analysis was performed using a water quality model. The results of this study showed that the target water quality of the Yeongsan river could be achieved if flow increase strategies (FISs) are intensively pursued in parallel with pollution reduction. The reason is because the water quality of the river has been steadily improved through pollution reduction but this method is now nearing the limit. In addition, rainfall-related FISs such as dam construction and water distribution adjustment may be less effective or lost if a megadrought continues due to climate change and then rainfall does not occur for a long time. Therefore, in the future, if the application conditions for the FISs are similar, the seawater desalination facility, which is independent of rainfall, should be considered as the priority installation target among the FISs. The reason is that seawater desalination facilities can replace the water supply function of dams, which are difficult to newly build in Korea, and can be useful as a climate change adaptation facility by preventing water-related disasters in the event of a long-term megadrought.

A Study on Industries's Leading at the Stock Market in Korea - Gradual Diffusion of Information and Cross-Asset Return Predictability- (산업의 주식시장 선행성에 관한 실증분석 - 자산간 수익률 예측 가능성 -)

  • Kim Jong-Kwon
    • Proceedings of the Safety Management and Science Conference
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    • 2004.11a
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    • pp.355-380
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    • 2004
  • I test the hypothesis that the gradual diffusion of information across asset markets leads to cross-asset return predictability in Korea. Using thirty-six industry portfolios and the broad market index as our test assets, I establish several key results. First, a number of industries such as semiconductor, electronics, metal, and petroleum lead the stock market by up to one month. In contrast, the market, which is widely followed, only leads a few industries. Importantly, an industry's ability to lead the market is correlated with its propensity to forecast various indicators of economic activity such as industrial production growth. Consistent with our hypothesis, these findings indicate that the market reacts with a delay to information in industry returns about its fundamentals because information diffuses only gradually across asset markets. Traditional theories of asset pricing assume that investors have unlimited information-processing capacity. However, this assumption does not hold for many traders, even the most sophisticated ones. Many economists recognize that investors are better characterized as being only boundedly rational(see Shiller(2000), Sims(2201)). Even from casual observation, few traders can pay attention to all sources of information much less understand their impact on the prices of assets that they trade. Indeed, a large literature in psychology documents the extent to which even attention is a precious cognitive resource(see, eg., Kahneman(1973), Nisbett and Ross(1980), Fiske and Taylor(1991)). A number of papers have explored the implications of limited information- processing capacity for asset prices. I will review this literature in Section II. For instance, Merton(1987) develops a static model of multiple stocks in which investors only have information about a limited number of stocks and only trade those that they have information about. Related models of limited market participation include brennan(1975) and Allen and Gale(1994). As a result, stocks that are less recognized by investors have a smaller investor base(neglected stocks) and trade at a greater discount because of limited risk sharing. More recently, Hong and Stein(1999) develop a dynamic model of a single asset in which information gradually diffuses across the investment public and investors are unable to perform the rational expectations trick of extracting information from prices. Hong and Stein(1999). My hypothesis is that the gradual diffusion of information across asset markets leads to cross-asset return predictability. This hypothesis relies on two key assumptions. The first is that valuable information that originates in one asset reaches investors in other markets only with a lag, i.e. news travels slowly across markets. The second assumption is that because of limited information-processing capacity, many (though not necessarily all) investors may not pay attention or be able to extract the information from the asset prices of markets that they do not participate in. These two assumptions taken together leads to cross-asset return predictability. My hypothesis would appear to be a very plausible one for a few reasons. To begin with, as pointed out by Merton(1987) and the subsequent literature on segmented markets and limited market participation, few investors trade all assets. Put another way, limited participation is a pervasive feature of financial markets. Indeed, even among equity money managers, there is specialization along industries such as sector or market timing funds. Some reasons for this limited market participation include tax, regulatory or liquidity constraints. More plausibly, investors have to specialize because they have their hands full trying to understand the markets that they do participate in

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Extraction of Primary Factors Influencing Dam Operation Using Factor Analysis (요인분석 통계기법을 이용한 댐 운영에 대한 영향 요인 추출)

  • Kang, Min-Goo;Jung, Chan-Yong;Lee, Gwang-Man
    • Journal of Korea Water Resources Association
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    • v.40 no.10
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    • pp.769-781
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    • 2007
  • Factor analysis has been usually employed in reducing quantity of data and summarizing information on a system or phenomenon. In this analysis methodology, variables are grouped into several factors by consideration of statistic characteristics, and the results are used for dropping variables which have lower weight than others. In this study, factor analysis was applied for extracting primary factors influencing multi-dam system operation in the Han River basin, where there are two multi-purpose dams such as Soyanggang Dam and Chungju Dam, and water has been supplied by integrating two dams in water use season. In order to fulfill factor analysis, first the variables related to two dams operation were gathered and divided into five groups (Soyanggang Dam: inflow, hydropower product, storage management, storage, and operation results of the past; Chungju Dam: inflow, hydropower product, water demand, storage, and operation results of the past). And then, considering statistic properties, in the gathered variables, some variables were chosen and grouped into five factors; hydrological condition, dam operation of the past, dam operation at normal season, water demand, and downstream dam operation. In order to check the appropriateness and applicability of factors, a multiple regression equation was newly constructed using factors as description variables, and those factors were compared with terms of objective function used in operation water resources optimally in a river basin. Reviewing the results through two check processes, it was revealed that the suggested approach provided satisfactory results. And, it was expected for extracted primary factors to be useful for making dam operation schedule considering the future situation and previous results.

Study on the Small Fields Dosimetry for High Energy Photon-based Radiation Therapy (고에너지 광자선을 이용한 방사선 치료 시 소조사면에서의 흡수선량평가에 관한 연구)

  • Jeong, Hae-Sun;Han, Young-Yih;Kum, O-Yeon;Kim, Chan-Hyeong
    • Progress in Medical Physics
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    • v.20 no.4
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    • pp.290-297
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    • 2009
  • In case of radiation treatment using small field high-energy photon beams, an accurate dosimetry is a challenging task because of dosimetrically unfavorable phenomena such as dramatic changes of the dose at the field boundaries, dis-equilibrium of the electrons, and non-uniformity between the detector and the phantom materials. In this study, the absorbed dose in the phantom was measured by using an ion chamber and a diode detector widely used in clinics. $GAFCHROMIC^{(R)}$ EBT films composed of water equivalent materials was also evaluated as a small field detector and compared with ionchamber and diode detectors. The output factors at 10 cm depth of a solid phantom located 100 cm from the 6 MV linear accelerator (Varian, 6 EX) source were measured for 6 field sizes ($5{\times}5\;cm^2$, $2{\times}2\;cm^2$, $1.5{\times}1.5\;cm^2$, $1{\times}1\;cm^2$, $0.7{\times}0.7\;cm^2$ and $0.5{\times}0.5\;cm^2$). As a result, from $5{\times}5\;cm^2$ to $1.5{\times}1.5\;cm^2$ field sizes, absorbed doses from three detectors were accurately identified within 1%. Wheres, the ion chamber underestimated dose compared to other detectors in the field sizes less than $1{\times}1\;cm^2$. In order to correct the observed underestimation, a convolution method was employed to eliminate the volume averaging effect of an ion chamber. Finally, in $1{\times}1\;cm^2$ field the absorbed dose with a diode detector was about 3% higher than that with the EBT film while the dose with the ion chamber after volume correction was 1% lower. For $0.5{\times}0.5\;cm^2$ field, the dose with the diode detector was 1% larger than that with the EBT film while dose with volume corrected ionization chamber was 7% lower. In conclusion, the possibility of $GAFCHROMIC^{(R)}$ EBT film as an small field dosimeter was tested and further investigation will be proceed using Monte Calro simulation.

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Topographical Change Monitoring of the Sandbar and Estimation of Suspended Solid Flux in the Nakdong River Estuary - Focused on Jinudo - (낙동강 하구역 사주지형 변동과 부유사(SS) 수송량 산정 - 진우도를 중심으로 -)

  • Lee, I.C.;Lim, S.P.;Yoon, H.S.;Kim, H.T.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.2
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    • pp.70-77
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    • 2008
  • In this study, to establish countermeasure from marine casualties as a basic study fur long-term prediction of topographical change around Jinudo in the Nakdong river estuary, spatio-temporal topographical change monitoring was carried out. Also, in order to estimate the deposition variations concerning SS (Suspended Solid) flux which moved at St.S1 during neap and spring tide, respectively. From the topographical monitoring, it was found that the annual mean ground level and deposition rate were 141 mm and 0.36 mm/day and all parts except the northern part of Jinudo had the active topographical changes and a tendency to annually deposit. From vertical distribution of SS net fluxes, $SS_{LH}$ (latitudinal SS net flux) during spring tide overall flows average 28 $kg/m^2/hr$ (eastward), and $SS_{LV}$ (longitudinal SS net flux) flows average 11.1 $kg/m^2/hr$ (northward). And, $SS_{LH}$ overall flows average 4.8 $kg/m^2/hr$ (eastward), and $SS_{LV}$ flows average 1.5 $kg/m^2/hr$ (northward) during neap tide similar with spring tide. The depth averaged values of the latitudinal and longitudinal SS net fluxes during spring tide were approximately 6 times higher than those during neap tide. As result of, it was considered that topographical change of southern part of Jinudo was affected by resuspension of bottom sediments due to strong current in bottom layer during flood flow.

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