• Title/Summary/Keyword: Primary decomposition

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The Effect of Cultivated Wild Ginseng Extract on Preadipocyte Proliferation (산양산삼 추출물이 지방세포의 분화에 미치는 영향)

  • Kim, Byoung-Woo;Kwon, Ki-Rok
    • Journal of Pharmacopuncture
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    • v.10 no.3
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    • pp.29-35
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    • 2007
  • Objectives The purpose of this study is to investigate the effects of cultivated wild ginseng extract on primary cultured preadipocyte and adipocytes. Methods Diminish preadipocyte proliferation does primary role to reduce obesity. So, preadipocytes and adipocytes were performed on cell cultures with using Sprague-Dawley rats and treated with 0.01-1mg/ml cultivated wild ginseng extract. Result At all concentrations, cultivated wild ginseng extract wasn't show the suppress proliferation of preadipocytes significantly and failed to show effects on decomposition of adipocytes except high dosage. Conclusion Based on these findings, cultivated wild ginseng is not a suitable choice for the treatment of localized obesity.

Estimation of Thermal Aging Embrittlement of LWR Primary Pressure Boundary Components

  • Kim, Sunki;Kim, Yongsoo
    • Nuclear Engineering and Technology
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    • v.30 no.6
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    • pp.609-616
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    • 1998
  • Cast duplex stainless steels are extensively used for primary pressure boundary components. These components are, however, embrittled due to the precipitation of $\alpha$' phase by spinodal decomposition and other processes when exposed to reactor operating temperature for a design lifetime or life extension conditions. This report presents a procedure for estimating the current condition and the residual life of safety-related stainless steel components by using ANL database and correlations. The database of Charpy impact energy suggests that CF-8M grade is the most susceptible to thermal aging and CF-3 grade is the least. Thus, the integrity of CF-8M alleys may be degraded seriously and the degree of deterioration may exceed acceptance limit after several years of service in the nuclear reactors.

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Development of a Cast Tool Steel with Excellent Performance for Application to Cold-Work Press Dies (냉간프레스금형용 고성능 주강 개발)

  • Kang, Jun-Yun;Park, Jun-Young;Kim, Byunghwan;Kim, Hoyoung
    • Journal of the Korean Society for Heat Treatment
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    • v.31 no.6
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    • pp.290-299
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    • 2018
  • The microstructure of a newly developed alloy tool steel (KV1) for casting cold-work press dies was analyzed using advanced scanning electron microscopy. Its mechanical properties and durability in use as piercing inserts were tested. It contained a continuous network structure which originated from the micro-segregation during solidification and was composed of retained austenite and primary carbides. However, after quenching and tempering, its continuity was destroyed due to the decomposition of austenite. The discontinuous spatial distribution and the smaller amount of primary carbide in the network presented KV1 enhanced ductility compared to the common alloy (HK700). The reduced C and Cr, the addition of V resulted in a small amount of primary carbides which primarily consisted of MC, as well as fine and uniform dispersion of precipitates. Owing to these features, KV1 exhibited delayed initiation of chipping when used for piercing inserts.

Power Allocation in Heterogeneous Networks: Limited Spectrum-Sensing Ability and Combined Protection

  • Ma, Yuehuai;Xu, Youyun;Zhang, Dongmei
    • Journal of Communications and Networks
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    • v.13 no.4
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    • pp.360-366
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    • 2011
  • In this paper, we investigate the problem of power allocation in a heterogeneous network that is composed of a pair of cognitive users (CUs) and an infrastructure-based primary network. Since CUs have only limited effective spectrum-sensing ability and primary users (PUs) are not active all the time in all locations and licensed bands, we set up a new multi-area model to characterize the heterogeneous network. A novel combined interference-avoidance policy corresponding to different PU-appearance situations is introduced to protect the primary network from unacceptable disturbance and to increase the spectrum secondary-reuse efficiency. We use dual decomposition to transform the original power allocation problem into a two-layer optimization problem. We propose a low-complexity joint power-optimizing method to maximize the transmission rate between CUs, taking into account both the individual power-transmission constraints and the combined interference power constraint of the PUs. Numerical results show that for various values of the system parameters, the proposed joint optimization method with combined PU protection is significantly better than the opportunistic spectrum access mode and other heuristic approaches.

Adaptive V1-MT model for motion perception

  • Li, Shuai;Fan, Xiaoguang;Xu, Yuelei;Huang, Jinke
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.1
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    • pp.371-384
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    • 2019
  • Motion perception has been tremendously improved in neuroscience and computer vision. The baseline motion perception model is mediated by the dorsal visual pathway involving the cortex areas the primary visual cortex (V1) and the middle temporal (V5 or MT) visual area. However, few works have been done on the extension of neural models to improve the efficacy and robustness of motion perception of real sequences. To overcome shortcomings in situations, such as varying illumination and large displacement, an adaptive V1-MT motion perception (Ad-V1MTMP) algorithm enriched to deal with real sequences is proposed and analyzed. First, the total variation semi-norm model based on Gabor functions (TV-Gabor) for structure-texture decomposition is performed to manage the illumination and color changes. And then, we study the impact of image local context, which is processed in extra-striate visual areas II (V2), on spatial motion integration by MT neurons, and propose a V1-V2 method to extract the image contrast information at a given location. Furthermore, we take feedback inputs from V2 into account during the polling stage. To use the algorithm on natural scenes, finally, multi-scale approach has been used to handle the frequency range, and adaptive pyramidal decomposition and decomposed spatio-temporal filters have been used to diminish computational cost. Theoretical analysis and experimental results suggest the new Ad-V1MTMP algorithm which mimics human primary motion pathway has universal, effective and robust performance.

Primary Production and Litter Decomposition of Macrophytes in the Sihwa Constructed Wetlands (시화호 인공습지에서 수생식물의 유기물 생산과 낙엽 분해)

  • Choi, Kwangsoon;Kim, Ho Joon;Kim, Dong Sub;Cho, Kang Hyun
    • Journal of Wetlands Research
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    • v.15 no.3
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    • pp.347-356
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    • 2013
  • To provide the information for the wetland management considering the water treatment ability of macrophytes, the growth characteristics and primary production by reed (Phragmites australis) and cattail (Typha angustifolia), and the decomposition rate of organic matter produced were investigated in two sub-wetlands (Banweol and Donhwa wetlands) of the Sihwa Constructed Wetland (CW) with different chemistry of inflows. The shoot height of P. australis and Typha angustifolia began to increase in March, and reached its peaks in July and August (340cm and 320cm, respectively). The shoot density of P. australis ranging $100{\sim}170EA/m^2$ was higher than that of T. angustifolia (max. $78EA/m^2$). Standing biomass of P. australis ranged from $1,350{\sim}1,980gDM/m^2$, with maximal biomass in Banwol Upper Wetland. And it was larger in upper wetlands than lower wetlands. On the other hand standing biomass of T. angustifolia ($1,940gDM/m^2$) was similar to that of P. australis in Banwol Upper Wetland. Primary productivity of P. australis was in the order of Banwol Upper Wetland ($2,050gDM/m^2/yr$) > Donghwa Lower Wetland ($1,840gDM/m^2/yr$) > Banwol Lowerr Wetland ($1,570gDM/m^2/yr$) ${\fallingdotseq}$ Donghwa Lower Wetland ($1,540gDM/m^2/yr$), and that of T. angustifolia ($2,210gDM/m^2/yr$) was higher than P. australis. Annual production of organic matter produced by P. australis and T. angustifolia was 845 ton DM/yr (423 ton C/yr), and about 90% was comprised of that by P. australis. From the litter decomposition rate (k) (P. australis: leaf 0.0062/day, stem 0.0018/day; T. angustifolia: leaf 0.0031/day, stem 0.0018/day), leaf was rapid degraded compare to stem in both P. australis and T. angustifolia. The litter decomposition rate of leaf was two times rapid P. australis than T. angustifolia, whereas that of stem was same in both. Annual litter decomposition amount of P. australis than T. angustifolia was 285 ton C/yr(67.3% of organic matter produced by macrophytes), indicating that 32.7% of organic matter produced by macrophytes is accumulated in the Sihwa CW.

The Factors Influencing Service Outcomes of Group Homes and Residential Care Centers : Focusing on Blinder-Oaxaca Decomposition (그룹홈과 아동양육시설의 운영성과에 영향을 미치는 요인 : Blinder-Oaxaca 분해를 중심으로)

  • Chung, Ick Joong;Woo, Seok Jin;Kang, Hyun Ah;Chun, Jong Serl;Lee, Jung Ae
    • Korean Journal of Child Studies
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    • v.33 no.4
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    • pp.107-127
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    • 2012
  • This study investigates the factors influencing service outcomes of group homes and residential care centers, as well as the factors causing any differences between the two service outcomes. 119 and 137 5-6th graders were selected from group homes and residential care centers respectively, using the cluster sampling method. Multiple regression and Blinder-Oaxaca decomposition were used in this study. The results revealed that 'stigma', 'school adjustment', and 'social support' were significant factors influencing service outcomes among children in group homes, while 'stigma', 'primary caregivers' attitude', and 'peer relations' were identified as significant factors among children in residential care centers. The study also found that the mean service outcome score for group homes was higher than that of residential care centers. The 74 percent of this difference in the mean scores was due to the difference in children' characteristics of the two out-of-home care service types. The remaining 26 percent of this difference was due to unobserved characteristics. Finally, the implications of this study in child welfare practices were also discussed.

Synthesis of $\beta$-Alumina By Oxalate Coprecipitation Method and Its Crystallization Behavior (Oxalate 공침법에 의한 $\beta$-Alumina 합성과 결정화 거동)

  • 박용민;양유철;김형욱;박성수;손영국
    • Journal of the Korean Ceramic Society
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    • v.32 no.4
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    • pp.455-461
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    • 1995
  • To investigate the synthesis of $\beta$-Al2O3 and its crystallization behavior by oxalate coprecipitation method, the optimum pH range for oxalate coprecipitates has been theoretically calculated from the solubility products and the equilibrium constans of each metal ionic species and their solubility diagram wa obtained. The optimum pH range for oxalate coprecipitates at room temperature was estimated as <4. In experiment, we found that the optimum condition for oxalate coprecipitates was pH<1, which was not doped with pH controller. The Na+ ions were easily exchanged for the NH4+ ions of NH4OH which was used as pH controller, and those NH4+ ions were supposed to affect the crystallization behavior of $\beta$-Al2O3. The thermal decomposition of all complexes was almost complete below 40$0^{\circ}C$. The primary product of the decomposition process was m-Al2O3, which transformed to $\beta$"- or $\beta$-Al2O3 at temperature higher than 100$0^{\circ}C$. We found that the powder prepared at 120$0^{\circ}C$ had only $\beta$"- and $\beta$-Al2O3.EX>-Al2O3.

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Has Income-related Inequity in Health Care Utilization and Expenditures Been Improved? Evidence From the Korean National Health and Nutrition Examination Survey of 2005 and 2010

  • Kim, Eunkyoung;Kwon, Soonman;Xu, Ke
    • Journal of Preventive Medicine and Public Health
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    • v.46 no.5
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    • pp.237-248
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    • 2013
  • Objectives: The purpose of this study is to examine and explain the extent of income-related inequity in health care utilization and expenditures to compare the extent in 2005 and 2010 in Korea. Methods: We employed the concentration indices and the horizontal inequity index proposed by Wagstaff and van Doorslaer based on one- and two-part models. This study was conducted using data from the 2005 and 2010 Korean National Health and Nutrition Examination Survey. We examined health care utilization and expenditures for different types of health care providers, including health centers, physician clinics, hospitals, general hospitals, dental care, and licensed traditional medical practitioners. Results: The results show the equitable distribution of overall health care utilization with pro-poor tendencies and modest pro-rich inequity in the amount of medical expenditures in 2010. For the decomposition analysis, non-need variables such as income, education, private insurance, and occupational status have contributed considerably to pro-rich inequality in health care over the period between 2005 and 2010. Conclusions: We found that health care utilization in Korea in 2010 was fairly equitable, but the poor still have some barriers to accessing primary care and continuing to receive medical care.

A Technical Review of Endothermic Fuel Use on Supersonic Flight (고속비행체에서 흡열연료의 이용기술 동향)

  • Kim, Joong-Yeon;Park, Sun-Hee;Chun, Byung-Hee;Kim, Sung-Hyun;Jeong, Byung-Hun;Han, Jeong-Sik
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.11a
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    • pp.93-96
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    • 2009
  • Advances in high speed flight technologies and engine efficiencies increase heat load on the aircraft. As the temperature of air flow is too high to cool the structure at hypersonic flight speeds, it is necessary to utilize the aircraft fuel as the primary coolant. By undergoing endothermic reaction, such as thermal decomposition or catalytic decomposition, aircraft fuels have heat sink potential. These fuels are called endothermic fuels. The endothermic reaction can be improved by catalysts, but limited by coke deposition. In this study the essential technologies of endothermic fuels are described, and intended to be used for basic research.

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