• Title/Summary/Keyword: energy deficit

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Three-Dimensional Computational Flow Analysis on Meteorological-Tower Shading Effect (풍황탑 차폐영향 분석을 위한 3차원 전산유동해석)

  • Rhee, Hui-Nam;Kim, Tae-Sung;Jeon, Wan-Ho;Kim, Hyun-Goo
    • Journal of the Korean Solar Energy Society
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    • v.33 no.1
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    • pp.1-6
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    • 2013
  • It is difficult to avoid measurement errors caused by the shading effect of the meteorological tower, which is used for wind resource assessment according to the IEC Standard. This paper presents a validation of the computational flow analysis results by comparing the results with the wind tunnel experiment conducted for Reynolds numbers in the $10^4$ to $10^5$ range, for the preparation of a database for use in an automatic method of correcting met-tower shading errors. A three-dimensional simulation employing the MP (Modified Production) $k-{\varepsilon}$ turbulence model predicted a wind speed deficit in the wake region according to minimum wind speed ratio, within an MAE (Mean Absolute Error) of 2.4%.

An Energy Budget Algorithm for a Snowpack-Snowmelt Calculation (스노우팩-융설 계산을 위한 에너지수지 알고리즘)

  • Lee, Jeong-Hoon;Ko, Kyung-Seok
    • Journal of Soil and Groundwater Environment
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    • v.16 no.5
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    • pp.82-89
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    • 2011
  • Understanding snowmelt movement to the watershed is crucial for both climate change and hydrological studies because the snowmelt is a significant component of groundwater and surface runoff in temperature area. In this work, a new energy balance budget algorithm has been developed for melting snow from a snowpack at the Central Sierra Snow Laboratory (CSSL) in California, US. Using two sets of experiments, artificial rain-on-snow experiments and observations of diel variations, carried out in the winter of 2002 and 2003, we investigate how to calculate the amount of snowmelt from the snowpack using radiation energy and air temperature. To address the effect of air temperature, we calculate the integrated daily solar radiation energy input, and the integrated discharge of snowmelt under the snowpack and the energy required to generate such an amount of meltwater. The difference between the two is the excess (or deficit) energy input and we compare this energy to the average daily temperature. The resulting empirical relationship is used to calculate the instantaneous snowmelt rate in the model used by Lee et al. (2008a; 2010), in addition to the net-short radiation. If for a given 10 minute interval, the energy obtained by the melt calculation is negative, then no melt is generated. The input energy from the sun is considered to be used to increase the temperature of the snowpack. Positive energy is used for melting snow for the 10-minute interval. Using this energy budget algorithm, we optimize the intrinsic permeability of the snowpack for the two sets of experiments using one-dimensional water percolation model, which are $52.5{\times}10^{-10}m^2$ and $75{\times}10^{-10}m^2$ for the artificial rain-on-snow experiments and observations of diel variation, respectively.

The Development for Blending Brake System of Electrical Multiple Unit used by Electric Brake (전기제동을 이용한 전동차의 혼합제동장치의 개발방향)

  • Lee, Woo-Dong
    • Proceedings of the KIEE Conference
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    • 2008.04c
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    • pp.155-157
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    • 2008
  • An electric multiple unit(EMU) consists of car body, bogie and brake equipment which is directly related to safety and performance of the motorcar. The blending brake mixed an electric brake and a friction brake is to reduce the energy by applying the restoration energy caused when the motorcar is stopped to car lines and to curtail the maintenance cost by saving the friction brake use. We have developed the advanced EMU since 2004, based on the experiences on the standard EMU in 1999, and we develop the installation which minimizes the use rate of the friction air brake by maximizing the electric brake use in the existing blending brake. We could accomplish the goal by improving the motorcar's Performance and solving the restoration energy's deficit by the friction brake. Actually, when it comes to the test results of standard EMU, except the service brake, in most conditions, we use electric brake to meet the requirements of the necessary brake power, exclusive when the motorcar leaves and stops. Therefore, in this paper, we consider the design concept of motorcar's blending brakes and suggest the way to develop the blending brake using the electric brake maximumly, which is caused by adequately controling the electric brake and the restoration brake.

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The Study on Treatment of Attention Deficit Hyperactivity Disorder by Oriental Medicine Music Therapy (주의력결핍 과잉행동 장애의 원인(原因) 및 병기(病機)에 따른 한방음악치료의 기법(機法)에 관한 연구)

  • Lee, Seung-Hyun;Kim, Yeo-Jin
    • The Journal of Pediatrics of Korean Medicine
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    • v.23 no.1
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    • pp.115-126
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    • 2009
  • Objectives The purpose of this study is to introduce oriental medicine music therapy related to the treatment of ADHD. Methods This study observed ADHD from the oriental medical point of view and tried to treat this disease with the oriental medicine music therapy. Results ADHD is caused by excess of Yang energy, flaming-up of fire, blood deficiency of the heart and the spleen, deficiency of the kidney essence, and instability of emotions. The ADHD patients with the case of excess of Yang energy and flaming-up of fire, patients were played Fire-Gi rhythm as a treatment, and they listened to Metal-Gi music. Whereas, the ADHD patient with blood deficiency of the heart and the spleen, invigoration of vital energy music therapy can be used. Another case of ADHD patients with deficiency of the kidney, Water-Gi rhythm and replenishing vital essence music therapy can be used. According to the patients' seven modes of emotions, the proper music should be chosen. Conclusions Oriental medicine music therapy can be a new type of treatment for ADHD patients.

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Effect of Dietary Energy and Protein Contents on Buffalo Milk Yield and Quality during Advanced Lactation Period

  • Bovera, F.;Calabro, S.;Cutrignelli, M.I.;Di Lella, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.5
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    • pp.675-681
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    • 2002
  • Among Italian buffalo farmers, it is widely held that administering diets with high energy and protein concentrations is an effective way to increase milk production. In order to assess the validity of this opinion, we verified milk yield and physico-chemical characteristics from buffaloes that, from the $5^{th}$ month of lactation, were fed two total mixed rations (TMRs) which, given the same intake, should have led to satisfaction of protein requirements though with a slight energy deficit (diet A) or excessive amounts of energy and protein (diet B). Estimate of the energy and protein value of the diets and that of the corresponding requirements was carried out both by using two software programs derived from the Cornell Net Carbohydrate and Protein System (1992), and with the method set up by INRA researchers (1988). The results obtained show that the two diets administered did not result in significant changes to the quantity of milk produced. However, with Diet B the protein concentration in the milk was significantly (p<0.01) higher, although this was partly offset by the higher concentration (p<0.05) of non-protein nitrogen (NNP). The Group B buffaloes also showed significantly higher blood urea levels (p<0.01), with concentrations exceeding those considered physiological for lactating buffaloes. Finally, while administering Diet A the Body Condition Score (BCS) was close to 6.5 (Wagner et al., 1988), whereas in buffaloes which used Diet B it sometimes increased by over 0.5 points. As regards which of the two methods compared is more suitable for expressing dietary energy and protein value and corresponding requirements, we feel that due to the high variability in the Italian Mediterranean buffalo's milk production aptitude, it would be premature to express a judgement on methods which rest on a common scientific base and do not differ substantially.

Development of Optimal Reservoir System Operation Model for Water Supply by Applying MIP Technique and Reappraisal of Water Supply Capability of Nakdong River Basin (MIP에 의한 댐군연계운영 최적화모형 개발과 개발 모형에 의한 낙동강수계 용수공급능력 재평가)

  • Choe, Yeong-Song;An, Gyeong-Su;Park, Myeong-Gi
    • Journal of Korea Water Resources Association
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    • v.33 no.4
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    • pp.447-459
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    • 2000
  • Since the development of water resources is getting more difficult than ever before because of human-sociological condition, it would be necessary to develop a practically applicable technique for the management of water resources based on demand-side concept that could reduce unusable release for more effective and appropriate allocation of limited water resources. The objective of the study is to develop an optimal reservoir system operation model for water supply and energy augmentation by the combination of water budget analysis method in downstream area by MIP technique. The applicable study of the developed model was carried out and water supply capability of Nakdong river basin was re-evaluated by the developed model. The model has been found successful to guarantee appropriate water supply to the basin by means of deficit-supply management method and also turned out to be more practical tool for an optimal reservoir system operation model than other existing models.

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Assessment of Nutrient Intake and ADHD Score in Atopic Dermatitis Preschoolers (아토피 피부염 미취학 아동의 식행동, 영양 섭취 상태 및 주의력 결핍 과잉 행동 점수 평가)

  • Kang, Myung-Hwa;Kim, Eun-Young;Choi, Mi-Kyeong
    • Journal of the East Asian Society of Dietary Life
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    • v.19 no.4
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    • pp.493-502
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    • 2009
  • This study aimed to examine the relationship between nutrient intake and attention deficit hyperactivity (ADH) of children suffering atopic dermatitis. We examined clinical symptoms as well as the status of ADH and the dietary intake of 47 children with atopic dermatitis aged between 4 and 6 against 84 children in the control group. Family history of the atopic dermatitis group was significantly higher than the control group. There was no significant difference between the diet habit of the two groups. The daily energy intake of the atopic dermatitis group and the control group were 1,189.7 kcal and 1245.0 kcal, respectively. There was no significant difference between the nutrient intake of the two groups. In regards to the clinical symptom items, the point for 'anxieties' was 0.5 in the atopic dermatitis group, which was significantly higher than 0.3 of the control group (p<0.05). In terms of the detailed items in ADH assessed by kindergarten teachers, the point for 'changeable feeling' was 0.8 in the atopic dermatitis group, which was significantly higher than 0.5 of the control group (p<0.05). As for the correlation among nutrient intake, the ADH score and clinical symptoms, total fat intake (p<0.05) and animal fat intake (p<0.05) showed a significantly negative correlation with the point of ADH assessed by the teachers, while the intake of fiber (p<0.05) displayed a significantly negative correlation with the point of ADH assessed by the parents. Since atopic dermatitis and ADH may be caused by the same dietary factors, it will be necessary to conduct more studies in this field in the future. In addition, appropriate nutrition management will be necessary for children in the growing period who suffer from atopic dermatitis.

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Improvement in Performance of Cu2ZnSn(S,Se)4 Absorber Layer with Fine Temperature Control in Rapid Thermal Annealing System (Cu2ZnSn(S,Se)4(CZTSSe) 흡수층의 급속 열처리 공정 온도 미세 조절을 통한 특성 향상)

  • Kim, Dong Myeong;Jang, Jun Sung;Karade, Vijay Chandrakant;Kim, Jin Hyeok
    • Korean Journal of Materials Research
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    • v.31 no.11
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    • pp.619-625
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    • 2021
  • Cu2ZnSn(S,Se)4 (CZTSSe) based thin-film solar cells have attracted growing attention because of their earth-abundant and non-toxic elements. However, because of their large open-circuit voltage (Voc)-deficit, CZTSSe solar cells exhibit poor device performance compared to well-established Cu(In,Ga)(S,Se)2 (CIGS) and CdTe based solar cells. One of the main causes of this large Voc-deficit is poor absorber properties for example, high band tailing properties, defects, secondary phases, carrier recombination, etc. In particular, the fabrication of absorbers using physical methods results in poor surface morphology, such as pin-holes and voids. To overcome this problem and form large and homogeneous CZTSSe grains, CZTSSe based absorber layers are prepared by a sputtering technique with different RTA conditions. The temperature is varied from 510 ℃ to 540 ℃ during the rapid thermal annealing (RTA) process. Further, CZTSSe thin films are examined with X-ray diffraction, X-ray fluorescence, Raman spectroscopy, IPCE, Energy dispersive spectroscopy and Scanning electron microscopy techniques. The present work shows that Cu-based secondary phase formation can be suppressed in the CZTSSe absorber layer at an optimum RTA condition.

RPSMDSM: Residential Power Scheduling and Modelling for Demand Side Management

  • Ahmed, Sheeraz;Raza, Ali;Shafique, Shahryar;Ahmad, Mukhtar;Khan, Muhammad Yousaf Ali;Nawaz, Asif;Tariq, Rohi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.6
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    • pp.2398-2421
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    • 2020
  • In third world countries like Pakistan, the production of electricity has been quickly reduced in past years due to rely on the fossil fuel. According to a survey conducted in 2017, the overall electrical energy capacity was 22,797MW, since the electrical grids have gone too old, therefore the efficiency of grids, goes down to nearly 17000MW. Significant addition of fossil fuel, hydro and nuclear is 64.2%, 29% and 5.8% respectively in the total electricity production in Pakistan. In 2018, the demand crossed 20,223MW, compared to peak generation of 15,400 to 15,700MW as by the Ministry of Water and Power. Country faces a deficit of almost 4000MW to 5000MW for the duration of 2019 hot summer term. Focus on one aspect considering Demand Side Management (DSM) cannot oversea the reduction of gap between power demand and customer supply, which eventually leads to the issue of load shedding. Hence, a scheduling scheme is proposed in this paper called RPSMDSM that is based on selection of those appliances that need to be only Turned-On, on priority during peak hours consuming minimum energy. The Home Energy Management (HEM) system is integrated between consumer and utility and bidirectional flow is presented in the scheme. During peak hours of electricity, the RPSMDSM is capable to persuade less power consumption and accomplish productivity in load management. Simulations show that RPSMDSM scheme helps in scheduling the electricity loads from peak price to off-peak price hours. As a result, minimization in electricity cost as well as (Peak-to-Average Ratio) PAR are accomplished with sensible waiting time.

Plant Toxins and Detoxification Methods to Improve Feed Quality of Tropical Seeds - Review -

  • Makkar, H.P.S.;Becker, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.3
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    • pp.467-480
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    • 1999
  • Many antinutritional and toxic factors abound in tropical seeds, which are also generally rich in nutrients and therefore more prone to attack from herbivores. Antinutritional and toxic factors are considered to defend seeds against environmental vagaries and thus help to protect them. These factors though good for the plant, cause deleterious effects or are even toxic to animals and man. The conventional seeds cultivated for oil or non-oil purposes, and general aspects of antinutritional factors are not presented here as these have already been discussed widely by many workers. Deficits in conventional protein and energy sources in the tropics have stimulated a quest for alternative feeds both for animals and humans. This article attempts to highlight two new oilseed crops, Jatropha curcas and Moringa oleifera, and in addition deals with some under-utilized seeds with potential as animal feed. Most of these seed plants are adapted to various marginal growing conditions in the tropics and can help to mitigate the prevailing deficit in protein and energy sources. Antinutritional and toxic factors in seed or seed meal, various approaches to detoxify seed meal, and future research and development priorities for their exploitation as animal feeds are presented.