• Title/Summary/Keyword: internal generation

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Nitric Oxide Generation from Peritoneal Macrophages by Salvia miltiorrhiza Root Water Extract (단삼(丹蔘) 수침액에 의한 복강대식세포로부터 산화질소의 발생)

  • Jo, Hyun-Ju;Moon, Seok-Jae
    • The Journal of Internal Korean Medicine
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    • v.20 no.1
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    • pp.143-152
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    • 1999
  • Dansam, the root of Salvia miltiorrhiza Bge, (Labiatae), has a bitter taste and a slightly 'cold' property, and is nontoxic. In the present study, effect of Dansam on nitric oxide (NO) generation from peritoneal macrophags was examined. Dansam had no effect on NO generation by itself, whereas recombinant interferon-${\gamma}\;(rIFN-{\gamma})$ alone had modest activity. When Dansam was used in combination with $rIFN-{\gamma}$, there was a marked cooperative induction of NO generation in a dose-dependent manner, The optimal effect of Dansam on NO generation was shown at 6 hr after treatment with $rIFN-{\gamma}$. Furthermore, the effect of Dansam was mainly dependent on Dansam-induced tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ secretion. These results suggest that Dansam induces NO generation from macrophages by the result of Dansam-induced $TNF-{\alpha}$ secretion.

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Modeling of Stochastic Properties of Internal Heat Generation of an Office Building for Slab Cooling Storage (사무소건물의 슬래브축냉을 위한 내부발열부하의 확률적 성상 모델화)

  • Jung, Jae-Hoon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.12
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    • pp.836-842
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    • 2011
  • It has been shown that the air-conditioning system with slab cooling storage is effective in cutting peak load and utilizing nighttime electric power. The stochastic properties of internal heat generation which has great influence on the cooling load are examined in this paper. Based on the measured cooling load and electric power consumption in an office building with slab cooling storage, stochastic time series models to simulate these random processes are investigated. Furthermore, a calculated result by an optimal control method of thermal analysis taking into account the internal heat is compared with the measured cooling load.

Algorithm Calculating Optimal DG Capacity Considering Operating Deficit in Hybrid Internal Combustion Generation (하이브리드 내연발전에서 도서 운영 결손액을 고려한 분산전원 최적 용량 산정 알고리즘)

  • Son, Joon-Ho;Kim, Mi-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.10
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    • pp.655-660
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    • 2018
  • Internal combustion generation (ICG) is used to supply power to islands due to geographical characteristics, but there are some problems, such as considerable operating cost, salt pollution, and environmental pollution. For these islands, KEPCO pays a significant amount of operating deficit each year, especially for the fuel and servicing costs, which account for a large portion of this deficit. Integrated ICG (IICG) through an offshore cable between near islands is being considered to decrease servicing costs. Distributed generation (DG) is also being introduced on the islands because of the demand for a low-carbon society. In hybrid internal combustion generation (HICG), DG is introduced into IICG, which can be applied because the DG output is insufficient due to environmental characteristics, and the IICG is used as an auxiliary power source. Therefore, this paper proposes an algorithm to estimate the optimal DG capacity that can be introduced in accordance with the KEPCO operating deficit in the HICG. According to simulations, the optimal DG capacity depends on the fuel cost and load capacity. The validity of the proposed algorithm was confirmed for multiple islands with different peak loads.

A Study on Optimal Control of Slab Cooling Storage Considering Stochastic Properties of Internal Heat Generation (내부발열의 확률적 성상을 고려한 슬래브축냉의 최적제어)

  • Jung, Jae-Hoon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.6
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    • pp.313-320
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    • 2015
  • In this paper, a method to obtain the probability distribution of room temperature and cooling load is presented, when the internal heat generation is applied to the system as a disturbance in the air conditioning system with slab cooling storage. The probability distribution of room temperature and the cooling load due to the disturbance were examined in one room of an office building. When considering only the electric power consumption as a probability component, it was found that the effect on room temperature and cooling load is small, because the probability component of the measured electric power consumption in the building is small. On the other hand, when considering the stochastic fluctuations of electric power consumption together with the heat generated by human bodies, the mean value of the cooling load was about 2,300 W and the ratio of the standard deviations was 19% (10 o'clock in second day). It was revealed that the stochastic effects of internal heat generation acting on the air conditioning system with slab cooling storage are not small.

The impact of Caesalpinia Sappan L. on Oxidative Damage and Inflammatory Relevant Factor in RAW 264.7 Cells and HUVEC (소목(蘇木)이 산화적 손상 및 Raw 264.7 cell과 HUVEC에서의 염증 유관 인자에 미치는 영향)

  • Kang, Seong-Sun;Kim, Myung-Sin;Jo, Jae-Jun;Choi, Seong-An;Yang, Eui-Ho;Jeon, Sang-Yun;Choi, Chang-Won;Hong, Soek
    • The Journal of Internal Korean Medicine
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    • v.34 no.1
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    • pp.100-111
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    • 2013
  • Objectives : This study investigated the impact of Caesalpinia sappan L. on oxidative damage and inflammatory relevant factor in RAW 264.7 cells and human umbilical vein endothelial cells (HUVEC). Methods : We determined whether fractionated EtOH extracts of Caesalpinia sappan L. (CSL) inhibit free radical generation such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), reactive oxygen species (ROS) and nitric oxide (NO) and pro-inflammatory cytokines in lipopolysaccharide (LPS)-treated RAW 264.7 cells and HUVEC. Result : 1. DPPH removal capacity was increased by CSL. 2. LPS-induced ROS, and NO inhibitory capacity were increased by CSL. 3. LPS-induced cell death of Raw 264.7 cells was decreased by CSL. 4. The amount of cytokine generation in Raw 264.7 cell was decreased significantly by CSL. 5. The amount of cytokine generation in HUVEC was decreased significantly by CSL. Conclusions : These results suggest that CSL supplement may attenuate oxidative stress by elevated antioxidative processes, and suppress inflammatory mediator activation.

Analysis of the Electric Energy and Exhaust Heat Energy for the Application of Thermo-Electric Generation in a Gasoline Vehicle (열전발전 적용을 위한 가솔린차량의 전력 및 배기열 에너지 분석 연구)

  • 이영재;표영덕;김강출
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.1
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    • pp.99-105
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    • 2002
  • About 70% of energy input to internal combustion engine is rejected to atmosphere by heat. By utilizing this waste heat, a plenty of energy can be conserved in nationwide. One of possible ways is the thermoelectric generation to utilize engine's waste heat to provide auxiliary electric power. Under th is concept, we have been developing the thermoelectric generation system to replace the alternator by converting the waste heat in the engine's exhaust directly to electricity This system may reduce the shaft horse power of the engine, then improves the vehicle fuel economy and the exhaust emissions. In the present study, the characteristics of the electric energy and exhaust heal energy in city and highway mode driving conditions are analysed by using a gasoline passenger car. These results would be used to determine the optimum design parameters of the thermoelectric generation system.

THERMAL STRESSES IN A SEMI-INFINITE SOLID CYLINDER SUBJECTED TO INTERNAL HEAT GENERATION

  • DESHMUKH, KISHOR CHINTANAMRAO;QUAZI, YUSUF IQBAL
    • Communications of the Korean Mathematical Society
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    • v.30 no.4
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    • pp.505-513
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    • 2015
  • The present paper deals with the determination of displacement and thermal stresses in a semi-infinite circular cylinder defined as $0{\leq}r{\leq}b$, $0{\leq}z<{\infty}$, due to internal heat generation within it. A circular cylinder is considered having arbitrary initial temperature and subjected to time dependent heat flux at the fixed circular boundary (r = b) whereas the zero temperature at the lower surface (z = 0) of the semi-infinite circular cylinder. The governing heat conduction equation has been solved by using integral transform method. The results are obtained in series form in terms of Bessel functions. The results for displacement and stresses have been computed numerically and illustrated graphically.

Modeling of internal wave generation near a shelf slope by ocean finite element method

  • Lee, Kwi-Joo;Joa, Soon-Won;Eom, Ki-Chang
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.42 no.1
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    • pp.38-43
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    • 2006
  • The 3-D modeling of ocean finite element method(OFEM) using $k-{\varepsilon}$ turbulent model and tetrahedron grids has been used to investigate the internal wave generation during the expansion of the deep water from the open sea to the shelf with a simple shape, which can be widely used in the fields of submarine development, ocean environment and meteorology, etc. In this paper, the detailed configuration of internal wave with its length and height and also the distribution of salinity and turbulent kinematic energy, etc. were derived. It is hoped that this OFEM method can be successfully applied to the numerical calculation of internal wave for and the oceanographic problems (tidal flows around underwater hill, plateau, Georges Bank, etc.) and ocean engineering problems(flow past artificial sea reefs) in future.

INFLUENCE OF INCLUSION ON INTERNAL DEFECT IN MULTI-STAGE EXTRUSION

  • Yoshida Y.;Fukaya Y.;Yukawa N.;Ishikawa T.;Ito K.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.10b
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    • pp.51-54
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    • 2003
  • Internal defects such as chevron crack occasionally occur in the process of cold extrusion or cold drawing. It is known that the existence and property of inclusion greatly influences the generation of the internal crack. However, in the plastic working field, research about the effect of the inclusion on the fracture is not theoretically analyzed. This paper describes effects of the physical property of inclusion on the internal fracture generation in the process. Prediction of fracture was evaluated by critical damage value calculated by the equation of Cockcroft & Latham and its change by the inclusion physical property such as size and stiffness was investigated.

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