• Title/Summary/Keyword: Natural source

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Effects of Source-Sink Alteration on Dry Matter Accumulation and Protein Content in Soybean (콩에서 Source-Sink변경이 건물축적과 단백질함량에 미치는 영향)

  • Rac Chun, Seong;Ji Hee, park;Sei Joon, Park;Jae Young, Cho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.6
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    • pp.723-730
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    • 1995
  • Effects of leaf and pod removal on changes in dry weight and protein content of soybean [Glycine max (L.) Merr.] cultivar 'Hwangkeumkong' were measured at the research farm of Korea University in 1992. The upper 40% and lower 60% of leaves and pods were subjected to treatments at the growth stage of beginning pod(R3). Leaf dry weight of lower part was increased by upper leaf-lower pod removal, but seed dry weight of upper part was decreased. The upper leaf-lower pod removal also increased stem dry weight and decreased upper pod dry weight. Protein content was higher in lower leaves than upper leaves. Seed protein contents were decreased both upper leaf-lower pod removal and lower leaf-upper pod removal treatments. The upper leaf-lower pod removal showed the highest leaf and the lowest seed protein quantities among the five treatments. These results indicated that protein sources were moved from lower to upper parts but weak in remobilization from leaves for the long distance translocation during the reproductive growth period of soybean plants.an plants.

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A Study on Estimating Earthquake Magnitudes Based on the Observed S-Wave Seismograms at the Near-Source Region (근거리 지진관측자료의 S파를 이용한 지진규모 평가 연구)

  • Yun, Kwan-Hee;Choi, Shin-Kyu;Lee, Kang-Ryel
    • Journal of the Earthquake Engineering Society of Korea
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    • v.28 no.3
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    • pp.121-128
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    • 2024
  • There are growing concerns that the recently implemented Earthquake Early Warning service is overestimating the rapidly provided earthquake magnitudes (M). As a result, the predicted damages unnecessarily activate earthquake protection systems for critical facilities and lifeline infrastructures that are far away. This study is conducted to improve the estimation accuracy of M by incorporating the observed S-wave seismograms in the near source region after removing the site effects of the seismograms in real time by filtering in the time domain. The ensemble of horizontal S-wave spectra from at least five seismograms without site effects is calculated and normalized to a hypocentric target distance (21.54 km) by using the distance attenuation model of Q(f)=348f0.52 and a cross-over distance of 50 km. The natural logarithmic mean of the S-wave ensemble spectra is then fitted to Brune's source spectrum to obtain the best estimates for M and stress drop (SD) with the fitting weight of 1/standard deviation. The proposed methodology was tested on the 18 recent inland earthquakes in South Korea, and the condition of at least five records for the near-source region is sufficiently fulfilled at an epicentral distance of 30 km. The natural logarithmic standard deviation of the observed S-wave spectra of the ensemble was calculated to be 0.53 using records near the source for 1~10 Hz, compared to 0.42 using whole records. The result shows that the root-mean-square error of M and ln(SD) is approximately 0.17 and 0.6, respectively. This accuracy can provide a confidence interval of 0.4~2.3 of Peak Ground Acceleration values in the distant range.

A Study about Characteristics of Participants of Natural Dyeing Experience Program - Focused on the Natural Dyeing and Craft Center in Bosung - (천연염색 체험학습에 대한 태도 - 보성 천연염색 체험학습을 중심으로 -)

  • Kim, Jie-Yurn
    • The Research Journal of the Costume Culture
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    • v.17 no.1
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    • pp.55-67
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    • 2009
  • The purposes of this study are to examine the conditions of natural dyeing experience program as a personal learning experience and consumer's interest and the participants characteristics of natural dyeing program so as to collect the practical data about natural dyeing program. To examine the interest and the participants characteristics of natural dyeing program, the data was obtained from a convenient survey of 326 citizens and tourists over 15 years old from Gwangju-city and Bosung in Chonnam during May 15${\sim}$July 30 in 2006. It was analyzed by frequency and t-test using SPSS 10.0. The results of the survey were: 1) The 40% of respondents are interested in natural dyeing. 2) Only 19% of respondents have ever participated in natural dyeing experience program. 3) The participants characteristics such as motivation and time of participation, item and source of natural dyeing according to natural dyeing program were various. 4) 65% of respondents were satisfied with natural dyeing experience. As the number of participants of natural dyeing increases, consumer awareness about natural dyeing will increase and finally industrialization of natural dyeing may be advanced.

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Phytochemical Studies on Astragalus Root (2);Flavonoids and a Lignan

  • Lee, Eun-Ju;Yean, Min-Hye;Jung, Hye-Sil;Kim, Ju-Sun;Kang, Sam-Sik
    • Natural Product Sciences
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    • v.14 no.2
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    • pp.131-137
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    • 2008
  • From the 70% EtOH extract of the roots of Astragalus membranaceus (Leguminosae), eleven flavonoid derivatives and a lignan, were isolated and identified as liquiritigenin (1), daidzein (2), formononetin (3), sophorophenolone (4), calycosin (5), methylnissolin (6), isomucronulatol (7), isomucronulatol 7-O-glucoside (8), methylnissolin 3-O-glucoside (9), calycosin 7-O-glucoside (10), (+)-syringaresinol O-${\beta}$-D-glucoside (11), and isomucronulatol 7,2'-di-O-glucoside (12), by spectroscopic methods. This is the second report of the isoflavonoid derivatives sophorophenolone (4) and isomucronulatol 7,2'-di-O-glucoside (12) from a natural source, as well as the first report of compounds liquiritigenin (1), daidzein (2) and (+)-syringaresinol O-${\beta}$-D-glucoside (11) from the species A. membranaceus.

Experimental Study on Comparison of Flame Propagation Velocity for the Performance Improvement of Natural Gas Engine

  • Chung Jin Do;Jeong Dong Soo
    • Journal of Environmental Science International
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    • v.14 no.1
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    • pp.15-22
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    • 2005
  • Natural gas possesses several characteristics that make it desirable as an engine fuel; 1)lower production cost, 2)abundant commodity and 3)cleaner energy source than gasoline. Due to the physics characteristics of natural gas, the volumetric efficiency and flame speed of a natural gas engine are lower than those of a gasoline engine, which results in a power loss of $10-20{\%}$ when compared to a normal gasoline engine. This paper describes the results of a research to improve the performance of a natural gas engine through the modification and controls of compression ratio, air/fuel ratio, spark advance and supercharging and method of measuring flame propagation velocity. It emphasizes how to improve the power characteristics of a natural gas engine. Combustion characteristics are also studied using an ion probe. The ion probe is applied to measure flame speed of gasoline and methane fuels to confirm the performance improvement of natural gas engine combustion characteristics.

Lignans from the Roots of Berberis amurensis

  • Park, Hyun-Bong;Lee, Kyu-Ha;Kim, Ki-Hyun;Lee, Il-Kyun;Noh, Hyung-Jun;Choi, Sang-Un;Lee, Kang-Ro
    • Natural Product Sciences
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    • v.15 no.1
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    • pp.17-21
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    • 2009
  • Column chromatographic separation of the alcoholic extract from the roots of Berberis amurensis yielded eight phenolic constituents including six lignans, hanultarin (1), (-)-secoisolariciresinol (3), (+)-lyoniresinol (5), (+)-syringaresinol (6), (+)-syringaresinol-O-$\beta$-D-glucopyranoside (7), liriodendrin (8), and two phenylpropanoids, 4-glucosyloxy-3-methoxyphenyl trans-propenoic ethyl ester (2), trans-ferulic acid (4). The structures were determined on the basis of NMR spectroscopic data. All isolated compounds(1-8) were reported for the first time from this source. Compound 1 exhibited moderate cytotoxicity against four human cancer cell lines in vitro using sulforhodamin B bioassay.

A study of AC/DC combined emergency source for power system control (전력계통 제어를 위한 변전소 AC/DC 겸용 비상전원에 관한 연구)

  • Jun, Bum-Bae;Lee, Hyoung-Han;Kim, Chang-Gon;Ahn, Bo-Soon;Yun, Ki-Seob;Jung, Jong-Ki
    • Proceedings of the KIEE Conference
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    • 2005.11b
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    • pp.135-138
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    • 2005
  • This paper focuses on emergency source and control of substation against the consequence of power system breakdown or outage. the aim of the paper is to provide ideas and guidance concerning methods of using AC/DC combined emergency source for power system control to restore power system after unforseen events, such as outages caused by natural disaster. so the emergency source and lamp is very important for restoration control of substation after outage. therefore, this paper proposes countermeasure and method for security of substation emergency source and lamp which is restored at breakdown.

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Flexible Nonlinear Learning for Source Separation

  • Park, Seung-Jin
    • Journal of KIEE
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    • v.10 no.1
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    • pp.7-15
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    • 2000
  • Source separation is a statistical method, the goal of which is to separate the linear instantaneous mixtures of statistically independent sources without resorting to any prior knowledge. This paper addresses a source separation algorithm which is able to separate the mixtures of sub- and super-Gaussian sources. The nonlinear function in the proposed algorithm is derived from the generalized Gaussian distribution that is a set of distributions parameterized by a real positive number (Gaussian exponent). Based on the relationship between the kurtosis and the Gaussian exponent, we present a simple and efficient way of selecting proper nonlinear functions for source separation. Useful behavior of the proposed method is demonstrated by computer simulations.

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Optimal Thermal Design of a Single Heat Source in a Cavity (Cavity내의 단일 열원에 대한 최적 열적설계)

  • Yae, Y.T.;Choo, H.L.;Kim, H.W.
    • Solar Energy
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    • v.19 no.1
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    • pp.77-86
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    • 1999
  • The optimal thermal design of a single heat source on one wall of a vertical open top cavity was studied experimentally. The temperature and flow fields in the cavity were visualized. The objectives of this study is to obtain the best location of the single heat source and to examine the effects of heat source protrusion, substrate thermal conductivity and cavity aspect ratio on the natural convection cooling due to a single heat source. As the results, the cooling effect for the copper substrate is superior to that of the epoxy-resin substrate and is improved with increasing cavity width. For the epoxy-resin substrate of lower conductivity, the protrusion of the heaters plays a role in decreasing the cooling effect. The best location was the mid-height of the substrate.

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Optimizing Maillard Reaction for Development of Natural Seasoning Source Using Oyster Hydrolysate (굴 가수분해물을 이용한 천연조미소스 개발을 위한 마이얄 반응의 최적화)

  • Ryu, Tae-hyun;Kim, Jin-hee;Shin, Jiyoung;Kim, Hyeon-jeong;Yang, Ji-young
    • Journal of Life Science
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    • v.26 no.11
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    • pp.1269-1274
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    • 2016
  • The oyster is called "milk of sea" which is abundant in taurine, glycogen, cellenium. It could be used in making natural source. Recently, consumers have more interest in natural source because of their diverse preference and its special taste. The goal of this study is to optimize maillard reaction condition for manufacturing natural seasoning using oyster and oyster cooking drip hydrolysate. The result was judged by browning degree and pyrazine, which is flavor components when food heating. Hydrolysate and sugar react according primarily to type of sugar - glucose, xylose and fructose. Xylose was selected as best sugar of browning degree. In the case of sugar contents, all conditions over 1% of sugar contents are almost same. Therefore, the lowest 1% of sugar was selected as appropriate condition. According to the reaction with different temperature, browning degree and pyrazine contents had been increased over $60^{\circ}C$, but the product at $120^{\circ}C$had off-flavored. So, $100^{\circ}C$ is the best condition for the browning reaction. And in accordance with different reaction time, after 6 hours, there was no change in pyrazine and browning reaction. Therefore, to manufacture natural seasoning source, it is optimal to react xylose for maillard reaction at $100^{\circ}C$ for 6 hr with hydrolysate of oyster and oyster cooking drip.