• Title/Summary/Keyword: Various capacity

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Antioxidant capacity of crude extract and fractions from Woodfordia fruticosa flower

  • Bhatt, Lok Ranjan;Baek, Seung-Hwa
    • Advances in Traditional Medicine
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    • v.7 no.2
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    • pp.162-170
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    • 2007
  • Woodfordia fruticosa Kurz. (Lythraceae), commonly known as Dhayero, is used in the treatment of various ailments in Nepal. In this study, the antioxidant capacity of crude extract and different polarity fractions of Woodfordia fruticosa flowers were assayed for their scavenging abilities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide radicals, competitive ${\beta}$-carotene bleaching, reducing power, metal chelating ability and total phenolic content. Crude extract and polar fractions showed stronger antioxidant capacity and contained very high level of total phenolics. They exhibited strong DPPH radical scavenging, nitric oxide scavenging and reducing power, medium ${\beta}$-carotene bleaching and poor metal chelating capacity. Positive correlation obtained between total phenolic content and antioxidant capacity assays, indicated the contribution of phenolics toards antioxidant capacity.

Capacity Requirement Estimation of Shunt Active Power Filter for Thyristor Converter Load (싸이리스터 컨버터부하에 적용되는 병렬형 능동필터의 적정용량산정)

  • Park, No-Jung;Jeong, Seung-Gi
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.48 no.12
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    • pp.715-726
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    • 1999
  • This paper estimates the capacity of shunt type active power filters(APF) for harmonic/reactive power compensation with a thyristor converter load. The base capacity requirement of APF is defined for idealized converter load current waveform and the effect of commutation overlap on the APF capacity is examined. The APF capacity required for reactive power compensation in addition to the harmonic elimination is estimated to give maximum achievable power factor for various operating condition of the partially-loaded thyristor converter. The method of current limit of APF is introduced, and it is shown that the APF capacity can be considerably reduced by deliberately limiting the peak current while maintaining the filtering performance to meet the level std 519 regulation.

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Kinematic limit analysis of pullout capacity for plate anchors in sandy slopes

  • Yu, S.B.;Merifield, R.S.;Lyamin, A.V.;Fu, X.D.
    • Structural Engineering and Mechanics
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    • v.51 no.4
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    • pp.565-579
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    • 2014
  • The pullout capacity of plate anchors has been studied extensively over the past 40 years. However, very few studies have attempted to calculate the pullout capacity of anchors in sandy slopes. In this paper, three upper bound approaches are used to study the effect of a sloping ground surface and friction angle on pullout capacity and failure of plate anchors. This includes the use of; simple upper bound mechanisms; the block set mechanism approach; and finite element upper bound limit analysis. The aim of this research is to better understand the various failure mechanisms and to develop a simple methodology for estimating the pullout capacity of anchors in sandy slopes.

Global STI Capacity Index: Comparison and Achievement Gap Analysis of National STI Capacities

  • Bashir, Tariq
    • STI Policy Review
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    • v.6 no.2
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    • pp.105-145
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    • 2015
  • Science, technology and innovation (STI) is crucially important to eradicating poverty, and making advances in various areas such as agriculture, health, environment, transport, industry, and telecommunications. Therefore, it is vital to the overall socioeconomic development of nations. The indispensable role of STI in the competitive globalized economy led to several attempts to measure national STI capacities. The present study outlines STI capacity around three sets of capabilities: technological capabilities, social capabilities, and common capabilities. The Global Science, Technology and Innovation Capacity (GSTIC) index was developed to provide current evidence on the national STI capacities of the countries, and to improve the composite indicators used for such purposes. The GSTIC ranks a large number of countries (167) on the basis of their STI capacities and categories them into four groups: i.e. leaders, dynamic adopters, slow adopters, and laggards. For more meaningful assessment of the STI capacities of nations, it captures the achievement gaps of individual countries with the highest achiever. The study also provides ranking and achievement gaps of nations in the nine GSTIC pillars: technology creation, R&D capacity, R&D performance, technology absorption, diffusion of old technologies, diffusion of recent innovations, exposure to foreign technology, human capital, and enabling factors. A more detailed analysis of the strengths and weaknesses in different pillars of STI capacity of ten selected countries is also provided. The results show that there are significant disparities among nations in STI capacity and its various aspects, and developing countries have much to catch-up with the developed nations. However, different countries may adopt different strategies according to their strengths and weaknesses. Useful insight into the strengths and weaknesses of the national STI capacities of different countries are provided in the study.

An experimental study on the evaluation of discharge capacity for vertical plastic drain board (연직배수재의 통수능력평가를 위한 실험적 연구)

  • Kim, Joonseok;Lee, Kangil
    • Journal of the Society of Disaster Information
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    • v.13 no.4
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    • pp.483-490
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    • 2017
  • Recently, the demand for industrial and residental land are increasing with economic growth, but it is difficult to obtain the area for development with good ground condition. Various kinds of vertical drain technologies such as sand drain, sand compaction pile, packed drain, PVD are commercially available to improve the soft ground. Discharge capacity is the important factor of vertical drains. However, under field conditions, discharge capacity is changed with various reasons, such as soil condition, overburden pressure, and so on. In this paper, the experimental study was carried out to estimate the discharge capacity of four different types of PBD, PBD for double core PBD, deep type PBD, X type PBD, general type PBD. Characteristics of the discharge capacity for the surcharge load and hydraulic gradient were analysed. The double core PBD was excellent for discharge capacity in this study.

Failure mechanism and bearing capacity of inclined skirted footings

  • Rajesh P. Shukla;Ravi S. Jakka
    • Geomechanics and Engineering
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    • v.35 no.1
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    • pp.41-54
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    • 2023
  • The use of a skirt, a vertical projection attached to the footing, is a recently developed method to increase the bearing capacity of soils and reduce foundation settlements. Most of the studies were focused on vertical skirted circular footings resting on clay while neglecting the rigidity and inclination of skirts. This study employs finite element limit analysis to investigate the bearing capacity enhancement of flexible and rigid inclined skirts in cohesionless soils. The results indicate that the bearing capacity initially improves with an increase in the skirt inclination but subsequently decreases for both flexible and rigid skirts. However, the rigid skirt exhibits more apparent optimum skirt inclination and bearing capacity enhancement than the flexible one, owing to differences in their failure mechanisms. Furthermore, the bearing capacity of the inclined skirted foundation increases with the skirt length, footing depth, and internal friction angle of the soil. In the case of rigid skirts, the bearing capacity increases linearly with skirt length, while for flexible skirts, it reaches a stable value at a certain skirt length. The efficiency of the flexible footing reduces as the footing depth and soil internal friction angle increase. Conversely, the efficiency of the rigid skirt decreases only with an increase in the depth of the footing. The paper also presents a detailed analysis of various failure patterns, highlighting the behaviour of inclined skirted footings. Additionally, nonlinear regression equations are provided to quantify and predict the bearing capacity enhancement with the inclined skirts.

Discharging/Charging Voltage-Temperature Pattern Recognition for Improved SOC/Capacity Estimation and SOH Prediction at Various Temperatures

  • Kim, Jong-Hoon;Lee, Seong-Jun;Cho, Bo-Hyung
    • Journal of Power Electronics
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    • v.12 no.1
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    • pp.1-9
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    • 2012
  • This study investigates an application of the Hamming network-dual extended Kalman filter (DEKF) based on pattern recognition for high accuracy state-of-charge (SOC)/capacity estimation and state-of-health (SOH) prediction at various temperatures. The averaged nine discharging/charging voltage-temperature (DCVT) patterns for ten fresh Li-Ion cells at experimental temperatures are measured as representative patterns, together with cell model parameters. Through statistical analysis, the Hamming network is applied to identify the representative pattern that matches most closely with the pattern of an arbitrary cell measured at any temperature. Based on temperature-checking process, model parameters for a representative DCVT pattern can then be applied to estimate SOC/capacity and to predict SOH of an arbitrary cell using the DEKF. This avoids the need for repeated parameter measuremet.

Studies on the Adsorption Capacity of Cd and Zn by Genus Allium Powder in aqueous solution (Allium속의 Cd 및 Zn 흡착력)

  • Kim, Seong-Jo;Baek, Seung-Hwa;Mun, Gwang-Hyeon
    • The Korean Journal of Food And Nutrition
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    • v.9 no.3
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    • pp.307-313
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    • 1996
  • The study was performed under the various conditions, such as the edible parts and particle sizes of Allium, the concentrations, the temperatures, and the pH of heavy metal solutions to investigate their adsorption capacity of heavy metals by genus Allium. The adsorption amount of Cd by Allium in the aqueous solution was apparently higher than that of Zn by them. The larger the particle size of welsh onion and shallot was, the higher the adsorption of Cd was. But the adsorption ratio was not different. As the temperature increased, the amount of heavy metal adsorption increased in general, but the adsorption of Cd by wild garlic, Zn by garlic decreased. Adsorption of Cd and Zn to Allium was not affected by the various pH. The correlation between the amount of components in edible putts of Allium and that of adsorption of heavy metals was significantly high in amino acids containing sulfhydryl radical (-SH) and vitamin B2.

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Removal of Hydrogen Sulfide Using Porous Ceramic Biofilter Inoculated with Sulfur Oxidizing Bacteria (황산화 균주가 부착된 다공성 세라믹 biofilter를 이용한 $H_2S$ 제거)

  • 박상진;조경숙
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.5
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    • pp.649-655
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    • 1999
  • Biofiltration of polluted gas streams contained $H_2S$ was studied. The experiments were performed in a laboratory-scale reactor with a porous ceramic media inoculated with sulfur oxidizing bacterium, TAS which was isolated from activiated sludge. The concentration of $H_2S$ in the inlet gas varied from 109 to 3,841 ppm, at the various space velocities(SV) of 50 $h^{-1}$ to 250 $h^{-1}$. Various tests have been conducted to evaluate the effects of such parameters as pH, concentration of sulfate ion and retention time on the pressure drop and maximum elimination capacity. The removal efficiency of $H_2S$ decreased as the $H_2S$ concentration or gas velocity increased in the inlet gas. Pressure drop was insignificant in this system. The maximum elimination capacity could reach up to 16.35g-S/kg-dry packing material/day.

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Molecular Modeling Studies on the Functionalized MOF-5 (MOF-5 계열 화합물의 수소 흡착 용량 예측에 관한 분자모델링 연구)

  • Kim Dae Jin;Lee Tae Beom;Choi Seung Hun;Lee Eun Seong;Oh Yu Jin;Yun Ji Hye;Kim Ja Heon
    • 한국전기화학회:학술대회논문집
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    • 2004.06a
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    • pp.287-292
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    • 2004
  • In order to understand the relationship between molecular structure of Metal-Organic Framework(MOF) and capacity of hydrogen absorption, quantum mechanical calculations and grand canonical Monte Carlo simulations have been carried out on a series of MOF-5 having various organic linkers. The calculation results about specific surface area and electron density for various frameworks indicated that the capacity of the hydrogen storage is largely dependent on effective surface area rather than the free volume. Based on the iso-electrostatic potential surface from density functional calculation and the amount of adsorbed hydrogens from grand canonical Monte Carlo calculation, it was also found that the electron localization ground organic linker plays an important role in hydrogen capacity of MOFs.

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