• Title/Summary/Keyword: Adequate level

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An Analysis on the Adequate Level of Capacity Price from a Long-Term Generation Expansion Planning Perspective: the Case of Korea

  • Kim, Hyoungtae;Lee, Sungwoo;Kim, Tae Hyun;Shin, Hansol;Kim, Wook
    • Journal of Electrical Engineering and Technology
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    • v.13 no.6
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    • pp.2203-2211
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    • 2018
  • Capacity payment mechanism has been adopted as the incentive scheme to achieve resource adequacy in Korean electricity market, however, the level of capacity price has been controversial due to its insufficient extent to incur financial loss for certain generators. Therefore, a new method is proposed to estimate the proper level of capacity price incorporating profitability of market participants and resource adequacy in this paper. The proposed method is successfully applied to test system based on Korean power system.

Vibro-acoustic analysis of un-baffled curved composite panels with experimental validation

  • Sharma, Nitin;Mahapatra, Trupti R.;Panda, Subrata K.
    • Structural Engineering and Mechanics
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    • v.64 no.1
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    • pp.93-107
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    • 2017
  • The article presents the vibration and acoustic responses of un-baffled doubly curved laminated composite panel structure under the excitation of a harmonic point load. The structural responses are obtained using a simulation model via ANSYS including the effect various geometries (cylindrical, elliptical, spherical and hyperboloid). Initially, the model has been established by solving adequate number of available examples to show the convergence and comparison behaviour of the natural frequencies. Further, the acoustic responses are obtained using an indirect boundary element approach for the coupled fluid-structure analysis in LMS Virtual.lab by importing the natural frequency values. Subsequently, the values for the sound power level are computed using the present numerical model and compared with that of the available published results and in-house experimentally obtained data. Further, the acoustic responses (mean-square velocity, radiation efficiency and sound power level) of the doubly curved layered structures are evaluated using the current simulation model via several numerical experimentations for different structural parameters and corresponding discussions are provided in detail.

A Study on Size Effect for Compressive Strength of Concrete considering Strength Level (강도수준에 따른 콘크리트 압축강도의 크기효과에 관한 연구)

  • 김희성;진치섭;어석홍
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.239-244
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    • 1999
  • The reduction phenomena of the compressive strength of concrete with respect to the size of specimens have been extensively investigated. However, adequate analysis technique have not been developed until now. Existing researches have shown that the larger member size, the smaller the strength. This indicated the necessity of nonlinear fracture mechanics theory in order to analyze the fracture behaviors of concrete. The are some models that predict the size effect of compressive strength of cylindrical specimens. Theses equations, however, are developed not considering the difference of fracturing mechanism which depends on both geometry of specimen and the strength level of concrete. In this paper, a model to predict compressive strength of cylindrical concrete specimens with respect to diameters, h/d ratios, and the strength level of concrete, is suggested. For this purpose, theoretical and statistical analyses are conducted. Experimental constants used in the model of new size effect are formulated in terms of strength levels of concrete based on existing experimental data.

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Requirement Analysis for Development of EVMS in Nuclear Power Plant (원전건설 성과관리시스템(EVMS) 개발을 위한 요건 분석)

  • Won, Seo-Kyung;Park, Weon-Seob;Chong, Young-Whan;Kim, Jae-Yong;Kim, Yun-Myung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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    • pp.271-272
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    • 2013
  • The Korean nuclear industry acquired technology for each construction stage including engineering, procurement, construction and commissioning from advanced nuclear countries. While the levels of technology and quality have greatly improved, the same cannot be said for the level of project management. In particular, the level of project performance measurement and forecasting project risk still remain at the single project management level. Thus, this paper reviewed the concept of the EVMS method and requirement for the system. The adoption of the EVMS, an advanced project management method, can enable efficient management of project risks and promote an adequate environment for project implementation.

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Development of Pressurizer Level Control System using Centrifugal Charging Pump and Letdown Orifices for YGN 5&6

  • Jeong, Won-Sang;Shon, Suk-Whun;Seo, Ho-Taek;Seo, Jong-Tae;Lee, Sang-Keun
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05a
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    • pp.484-490
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    • 1996
  • The Pressurizer Level Control System (PLCS) logic for YGN 5&6 was developed to incorporate the design changes on the Chemical and Volume Control System (CVCS). The YGN 5&6 CVCS uses the centrifugal charging pumps and letdown orifices replacing the positive displacement pumps and letdown control valves in the YGN 3&4 and UCN 3&4. The purpose of this study is to develop new PLCS as well as validate newly developed control logic and its implementation method in the simulation computer code. The analysis results show that the new PLCS has adequate ability to control the pressurizer level in response to the design bases events, and the simulation computer code is useful for YGN 5&6 NSSS design code.

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A Study on the Optimum Mix and Exposing Method of the Fine-Size Exposed Aggregate PCC Pavements (소입경 골재노출콘크리트포장의 최적 배합 및 노출기법에 관한 연구)

  • Kim, Young-Kyu;Lee, Seung-Woo;Yoo, Tae-Seok;Kim, Hyung-Bae
    • International Journal of Highway Engineering
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    • v.11 no.2
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    • pp.1-15
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    • 2009
  • Surface of exposed aggregate concrete pavements is consists of exposed coarse aggregate by removing upper 2$\sim$3mm mortar of concrete slab. Exposed aggregate concrete pavements have advantages of maintaining low-noise and adequate skid-resistance level during the performance period. In order to provide the successful exposed concrete aggregate pavement, uniform distribution of the coarse aggregate on pavement surface through adequate the mix design and exposing method. The mix design in concrete pavement is generally designed on the basis of strength, but mix design of exposed aggregate pavement employed in this study includes the consideration of noise and skid resistance, as well as strength. Smaller of maximum coarse aggregate is known to be effective for reduce noise level. Optimum mix design and exposing method of fine-size exposed aggregate portland cement concrete pavement that can reducing the noise and maintain the adequate level of skid resistance are proposed in this study. To consider the variation of optimum exposing time due to the hardening speed of mortar by climatic condition, quantitative is also suggested measurement of hardening state.

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The Macro Mineral Contents in High Fat Diet-Induced Obese Rats Fed Various Amounts of Zinc (고지방식이 유도 비만쥐에서 아연 수준이 다량 무기질 함량에 미치는 영향)

  • Kim, Hyun-Sook;Sung, Chung-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.8
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    • pp.1032-1036
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    • 2009
  • This study was conducted to investigate the effect of dietary zinc on macro mineral contents of high fat diet-induced obese rats. The obese group was divided into three groups by zinc levels of diet, such as low (50% requirement), adequate (100%) and high (200%) levels of dietary zinc. The calcium, magnesium, sodium and potassium contents in serum and organs were measured by ICP. There were no significant differences in the food intake, weight gain and feed efficiency ratio among the different dietary zinc levels. Also, the liver, kidney and spleen weight did not show the significant differences among each level of dietary zinc. However, serum sodium and potassium concentrations in the low zinc diet group were significantly higher than in the other diet groups. In high zinc diet group, the calcium contents of liver was significantly higher than in the other diet groups, magnesium and potassium contents of liver were higher than in the low zinc diet group. The sodium contents of liver and magnesium and potassium contents of spleen were significantly lower in the low zinc diet group than in the other diet groups. In conclusion, the macro mineral contents of serum, liver and spleen in obese rats were changed by dietary zinc levels. Especially, the low zinc diet group considerably changed of macro mineral contents in organs. Therefore, it may be suggested that adequate level of dietary zinc in obese individuals should be required.

Degree of Enteral Tube Feeding in the Intensive Care Unit and Change in Nutritional Status (병원 중환자의 경관유동식 공급 현황 및 영양상태 변화)

  • Im, Hyeon-Suk;Park, Eun-Gyeong;Lee, Jong-Ho
    • Journal of the Korean Dietetic Association
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    • v.7 no.3
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    • pp.217-226
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    • 2001
  • It is important to supply adequate nutrition to critically ill patients, whose gastrointestinal system is properly functioning, through the enteral tube feeding if oral intake is impossible. In this study we investigated the changes in nutritional status with enteral tube feeding according to the volume required. We investigated the volume ordered according to the patient's requirements, volume infused according to the volume ordered in 41 enteral tube feeding patients in intensive care unit from Jannuary to July, 2000. Body weight, serum albumin level, and total lymphocyte count were evaluated to assess nutritional status. The mean fasting period was 5 days before the enteral feeding and patients whose fasting period over 3 days were 51%. The mean enteral tube feeding period was 29 days and method of feeding was nasogastric, bolus feeding 6 times per day. The volume ordered was 69.7% of the patients' recommended calorie and volume infused was 86.6% of their volume prescribed. Accordingly, the volume infused was estimated 61.7% of their volume required. Only 44.6% of their reqiured volume was infused within 3 days after enteral tube feeding was started. It took 16 days in average to meet the patients' recommended calorie; 56% of subjects still did not fully met their requirements by the end point. Among the impeding factors in supplying enteral tube feeding, factors related to the number of feeding were high residual volume in stomach, vomiting, gastrointestinal bleeding, abdominal distension and surgery. Factors related to the acctual infused volume were diarrhea, gastrointestinal bleeding, abdominal distension, airway management and tube reinsertion. Significant correlations were shown between the volume infused and changes in both the patients' weight and serum albumin level. Deviding the subjects into two groups by their infused volume, less than 70% and more than that, we compared the two to come up with a significant difference in their serum albumin level, -0.23 vs 0.21, and their body weight, -4.52 vs 0.12. In enteral tube feeding, the volume delivered in sufficient to the pateints' energy requirement can affect their nutriitional status in critically ill patient; adequate nutritional management plan is essential. It is necessary to make every effort to educate clinical staff and to set up a unified management program to prescribe adequate ammount of energy for the patient's nutritional requirement.

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Clothing Pressure Evaluation of Girdle and Waist Nipper and Related Wearing Conditions (거들 및 웨이스트니퍼 착용에 의한 의복압 평가 및 관련된 착용변인)

  • Lee, Heeran;Hong, Kyunghi;Kim, Yang Weon;Park, Se Jin
    • Science of Emotion and Sensibility
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    • v.16 no.1
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    • pp.1-10
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    • 2013
  • The purpose of this paper is to investigate the adequate clothing pressure of upper and lower body foundation garment and subjective assessment of those compressive foundation depending on various wearing conditions. Eighteen women in their 30s and 40s participated in the experiments for this study to evaluate the level of clothing pressure of girdle and waist nipper. Subjects were divided into two groups by the wearing habits of foundation, one is the group of wearing foundation garment 'tightly' and the other is 'loosely', It was found that the group wearing foundation garment 'loosely' was much more sensitive than the group of 'tightly' in everyday life. The adequate pressure of upper foundation, waist nipper was about $1.5{\pm}0.8$ kPa which is lower than that of the lower body foundation, girdle. And at the same time, the sensitivity of the pressure level was higher when subjects are wearing waist nipper compared with wearing girdle. Therefore, precise pattern making process is necessary to meet the adequate level of pressure of the upper body foundation such as waist nipper, specially for those who used to wear clothing loosely.

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EFFECTS OF DIETARY CELLULOSE LEVEL ON GROWTH PERFORMANCE DEVELOPMENT OF INTERNAL ORGANS, ENERGY AND NITROGEN UTILIZATION AND LIPID CONTENTS OF GROWING CHICKS

  • Siri, S.;Tobioka, H.;Tasaki, I.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.2
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    • pp.369-374
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    • 1992
  • In order to determine the effect of dietary cellulose levels on chick performance, 1-week-old White Leghorn male chicks were fed semi-purified diets containing either 5%, 10%, 15% or 20% cellulose for 3 weeks. All diets were iso-nitrogenous and iso-caloric. Feed intake and body weight were increased as the cellulose level was increased. Feed conversion was lower in the 5% cellulose diet than in the other diets. Compared to the case of 10% to 20% cellulose diets, relative length (per 100 g body weight) of esophagus, duodenum, small intestine and cecum was longer, and relative weight of esophagus, duodenum and crop was also heavier in the chicks fed the 5% cellulose diet. The other internal organs were not affected by the cellulose level. The retention rates of dry matter and nitrogen were lower in the 5% cellulose group than in the other groups. Concentration of carcass phospholipids was higher in the 5% cellulose group, and that of carcass cholesterol was increased as the cellulose level increased. In conclusion, the dietary cellulose level should be more than 5% to give an adequate chick performance, and no ill effect was found even at 20% level.