• Title/Summary/Keyword: Approximate period

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Changes in approximate composition, antioxidant activity and melatonin content of rapeseed during germination (발아기간에 따른 유채종자의 일반성분 조성, 항산화능 및 멜라토닌 함량의 변화)

  • Kim, Seok Joong
    • Food Science and Preservation
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    • v.23 no.6
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    • pp.839-847
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    • 2016
  • The changes of approximate composition, antioxidant activity and melatonin content in rapeseed were monitored during 10 days germination to choose the optimum sprouts with beneficial functionalities. The moisture content of seeds increased from 3.23% to 17.50% during 10 days germination period, while ash content was similar (4.03~4.91%). The fat content was reduced from 38.18% to 22.65%, however, protein content increased from 21.43% to 26.72%. The carbohydrate content increased from 32.71% to 35.84% at 8th day. The reducing sugar and fiber contents reached 10.47% and 15.12% at 6th day from 4.04% and 12.82%, respectively. Eighth day sprouts contained highest level of polyphenol (gallic acid equivalent, 19.2 g/kg). Germination increased antioxidant activities (trolox equivalent, mmol/kg) of seeds with slight difference depending on assay. That is, antioxidant activity was highest at 6th day in DPPH radical scavenging (55.9), 10th day both in ABTS radical scavenging (71.6) and Fe(III) reducing (125.3), and 4th day in peroxy radical scavenging (116.7) assay. Melatonin content of seeds ($0.85{\mu}g/kg$) also increased and reached up to $14.93{\mu}g/kg$ at 6th day. In conclusion, germination more than 4 days raised antioxidant activity of seeds highly, and 6th day sprouts had additional benefit in terms of melatonin, reducing sugar and crude fiber contents.

Yield and Nutritional Quality of Several Non-heading Chinese Cabbage (Brassica rapa var. chinensis) Cultivars with Different Growing Period and Its Modelling

  • Kalisz, Andrzej;Kostrzewa, Joanna;Sekara, Agnieszka;Grabowska, Aneta;Cebula, Stanislaw
    • Horticultural Science & Technology
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    • v.30 no.6
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    • pp.650-656
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    • 2012
  • The aims of the experiment, conducted over three years in the Central Europe field conditions, were (1) to investigate the effect of growing period (plantings in the middle and at the end of August: $1^{st}$ and $2^{nd}$ term, respectively) on yield and chemical composition of the non-heading Chinese cabbage (Brassica rapa var. chinensis) cultivars 'Taisai', 'Pak Choy White', and 'Green Fortune', and (2) to develop regression models to evaluate the changes in crop yields as a function of weather conditions. A highest marketable yield was obtained from 'Taisai' (65.71 and 77.20 $t{\cdot}ha^{-1}$), especially in the $2^{nd}$ term of production. Low yield, observed for 'Pak Choy White' was due to its premature bolting. Almost 39% ($1^{st}$ term) and 70% ($2^{nd}$ term) of plants of this cultivar formed inflorescence shoots before harvest. The highest dry matter level was observed in the leaf petioles of 'Taisai', while 'Green Fortune' was the most abundant of carotenoids and L-ascorbic acid. The content of soluble sugars was the lowest for 'Pak Choy White'. In a phase of harvest maturity, more of the analyzed constituents were gathered by plants from earlier plantings, and differences were as follows: 4.7% (dry matter), 26.3% (carotenoids) and 22.1% (L-ascorbic acid), in comparison to $2^{nd}$ term of production. Significant increase of soluble sugars level was observed for plants from later harvest. The regression model for marketable yield of Chinese cabbage cultivar 'Taisai' as a function of maximum air temperature can predict the yield with accuracy 68%. The models for yield or bolting of 'Pak Choy White', based on extreme air temperatures and sunshine duration, were more precise (98%). It should be pointed out that Taisai could be recommended for later growing period in Central Europe conditions with regard to maximum yield potential. 'Green Fortune' was notable for its uniform yielding. To obtained plants of higher nutritional value, earlier time of cultivation should be suggested. Described models can be successfully applied for an approximate simulation of Chinese cabbage yielding.

Archaeomagnetic Secular Variation of the Neolithic Age in Korea: Focusing on the Mid-Western Region Sites (한반도 신석기시대의 고고지자기 변동: 중서부지역 유적을 중심으로)

  • Sung, Hyong Mi
    • Journal of Conservation Science
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    • v.29 no.3
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    • pp.223-229
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    • 2013
  • It is not known in details for the A.D. period as the archaeomagnetic dating method to be fully facilitated in Korea but it has prepared for the revised shape of standard curve to trace the geomagnetic field variation, and there were cases to increase the survey on relics on the B.C. period to find out for the detailed archaeomagnetic field variation on the Bronze Age to the Early Iron Age. Furthermore, the survey cases on the relics on the Neolithic Age began to emerge a little by little archaeomagnetic field variation of the Neolithic Age through 34 pieces of the archaeomagnetic measurement data as making active advancement around mid-western region. Data is insufficient yet that it is difficult to find out the detailed trend of modification but it is estimated for approximate appearance. The archaeomagnetic field variation of the Neolithic Age made changes without breaking away from the scope of changes in the A.D. period as in the same way with the Bronze Age, and comparing to the variation of archaeomagnetic field for the Bronze Age, the magnetic inclination shifted within the scope of having almost no difference, but the declination is shown to skewed toward the east in its overall appearance. In addition, the comparison was made with the data of the Jomon Age in Japan and the archaeomagnetic measurement data of Korea has a little bit more depth for while the declination is skewed toward the east for 10 degree or more compared to those of Japan. However, in the part where the data is concentrated most intensely, the data for both countries has significant part to overlap to each other that the archaeomagnetic field variation of the Neolithic Age of Korea showed overall similar variation with certain partial changes when compared to those of Japan.

A Study on the Evaluation Method of Soil Treatment Termiticide (흰개미 토양처리제 효과 평가 및 시험방안 연구)

  • Im, Ik Gyun;Jeong, Seon Hye;Chung, Yong Jae
    • Journal of Conservation Science
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    • v.35 no.2
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    • pp.177-186
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    • 2019
  • A Termiticide that is applied to the soil treatment method, one of the methods for preventing termites in Korea's wooden cultural properties, will be subjected to the leaching of the effective ingredient in treated soil by the moisture behavior of rain. As a result, termiticide is deteriorated and needs to be reprocessed, but the standards and evaluation methods are nonexistent in korea. Accordingly, a basic indoor evaluation measure was proposed for the evaluation of the effectiveness of the termiticide chamber and the calculation of the reprocessing period. First, avoidance and contact toxicity were assessed at two concentrations of the same termiticide as a method for assessing termiticide suitability. The evaluation of mortality revealed that the soil termiticide used in this experiment was non-repellent, and that death from contact was confirmed. Afterwards, artificial rainfall and soil penetration tests were conducted to determine efficacy of termiticide in soil and the approximate reprocessing period was calculated by comparing the weather data. Persistence evaluation revealed perforation by termites after continuous water exposure of more than about 160 to 170mm of water injection condition. Based on the results, compared with weather data for the last five years, the termiticide of concentration used in this experiment is expected to remain effective for about one year if treated after September. The purpose of this study was to provide basic data for the establishment of a manual for the selection of termiticide for soil treatment by calculating the efficacy for termite mortality and the duration of the leaching effectiveness by water behavior in soil.

EFFICIENCY OF ENERGY TRANSFER BY A POPULATION OF THE FARMED PACIFIC OYSTER, CRASSOSTREA GIGAS IN GEOJE-HANSAN BAY (거제${\cdot}$한산만 양식굴 Crassostrea gigas의 에너지 전환 효율)

  • KIM Yong Sool
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.13 no.4
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    • pp.179-183
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    • 1980
  • The efficiency of energy transfer by a population of the farmed pacific oyster, Crassostrea gigas was studied during culture period of 10 months July 1979-April 1980, in Geoje-Hansan Bay near Chungmu City. Energy use by the farmed oyster population was calculated from estimates of half-a-month unit age specific natural mortality rate and data on growth, gonad output, shell organic matter production and respiration. Total mortality during the culture period was estimated approximate $36\%$ from data on survivor individual number per cluster. Growth may be dual consisted of a curved line during the first half culture period (July-November) and a linear line in the later half period (December-April). The first half growth was approximated by the von Bertalanffy growth model; shell height, $SH=6.33\;(1-e^{0.2421(t+0.54)})$, where t is age in half-a-month unit. In the later half growth period shell height was related to t by SH=4.44+0.14t. Dry meat weight (DW) was related to shell height by log $DW=-2.2907+2.589{\cdot}log\;SH,\;(2, and/or log $DW=-5.8153+7.208{\cdot}log\;SH,\;(5. Size specific gonad output (G) as calculated by condition index of before and after the spawning season, was related to shell height by $G=0.0145+(3.95\times10^{-3}{\times}SH^{2.9861})$. Shell organic matter production (SO) was related to shell height by log $SO=-3.1884+2.527{\cdot}1og\;SH$. Size and temperature specific respiration rate (R) as determined in biotron system with controlled temperature, was related to dry meat weight and temperature (T) by log $R=(0.386T-0.5381)+(0.6409-0.0083T){\cdot}log\;DW$. The energy used in metabolism was calculated from size, temperature specific respiration and data on body composition. The calorie contents of oyster meat were estimated by bomb calorimetry based on nitrogen correction. The assimilation efficiency of the oyster estimated directly by a insoluble crude silicate method gave $55.5\%$. From the information presently available by other workers, the assimilation efficiency ranges between $40\%\;and\;70\%$. Twenty seven point four percent of the filtered food material expressed by energy value for oyster population was estimated to have been rejected as pseudofaeces : $17.2\%$ was passed as faeces; $35.04\%$ was respired and lost as heat; $0.38\%$ was bounded up in shell organics; $2.74\%$ was released as gonad output, $2.06\%$ was fell as meat reducing by mortality. The remaining $15.28\%$ was used as meat production. The net efficiency of energy transfer from assimilation to meat production (yield/assimilation) of a farm population of the oyster was estimated to be $28\%$ during culture period July 1979-April 1980. The gross efficiency of energy transfer from ingestion to meat production (yield/food filtered) is probably between $11\%\;and\;20\%$.

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The Nonlinear Direct Spectrum Method Improving Application and Reliability of Existing Approximate Nonlinear Methods (기존 비선형약산법들의 신뢰성 개선을 위한 비선형직접스펙트럼법)

  • Kim, Jae-Ung;Kang, Pyeong-Doo;Jun, Dae-Han
    • Journal of the Earthquake Engineering Society of Korea
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    • v.10 no.4 s.50
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    • pp.55-66
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    • 2006
  • This paper considers the nonlinear direct spectrum method to estimate seismic performance of mixed building structures without iterative computations, given dynamic property $T_1$ from stiffness skeleton curve and nonlinear pseudo acceleration $A_{1y}/g$ and/or ductility ratio p from response spectrum. Nonlinear response history analysis has been performed and analysed with various earthquakes for evaluation of correctness and confidence of nonlinear direct spectrum method. The conclusions of this study are as follows; (1) Nonlinear direct spectrum method is considered as a practical method which is applicable to compute the structural initial elastic period and the yielding strength from stiffness skeleton owe and calculate the nonlinear maximum response of structure directly from nonlinear response spectrum. (2) The comparison of the analysis results from NDSM and NRHA showed that the average errors were less than 20% in about 3/4 of the analysis cases, and that the results obtained from NDSM turned out to be generally larger than those from NRHA.

Accuracy and applicable range of a reconstruction technique for hybrid rockets

  • Nagata, Harunori;Nakayama, Hisahiro;Watanabe, Mikio;Wakita, Masashi;Totani, Tsuyoshi
    • Advances in aircraft and spacecraft science
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    • v.1 no.3
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    • pp.273-289
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    • 2014
  • Accuracy of a reconstruction technique assuming a constant characteristic exhaust velocity ($c^*$) efficiency for reducing hybrid rocket firing test data was examined experimentally. To avoid the difficulty arising from a number of complex chemical equilibrium calculations, a simple approximate expression of theoretical $c^*$ as a function of the oxidizer to fuel ratio (${\xi}$) and the chamber pressure was developed. A series of static firing tests with the same test conditions except burning duration revealed that the error in the calculated fuel consumption decreases with increasing firing duration, showing that the error mainly comes from the ignition and shutdown transients. The present reconstruction technique obtains ${\xi}$ by solving an equation between theoretical and experimental $c^*$ values. A difficulty arises when multiple solutions of ${\xi}$ exists. In the PMMA-LOX combination, a ${\xi}$ range of 0.6 to 1.0 corresponds to this case. The definition of $c^*$ efficiency necessary to be used in this reconstruction technique is different from a $c^*$ efficiency obtained by a general method. Because the $c^*$ efficiency obtained by average chamber pressure and ${\xi}$ includes the $c^*$ loss due to the ${\xi}$ shift, it can be below unity even when the combustion gas keeps complete mixing and chemical equilibrium during the entire period of a firing. Therefore, the $c^*$ efficiency obtained in the present reconstruction technique is superior to the $c^*$ efficiency obtained by the general method to evaluate the degree of completion of the mixing and chemical reaction in the combustion chamber.

Measurement of Archaeomagnetic Secular Variation in Korea (한국에 있어서 지자기 영년변화의 측정)

  • 성형미
    • The Korean Journal of Quaternary Research
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    • v.16 no.2
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    • pp.33-38
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    • 2002
  • 28 direction of the past Korean geomagnetic field were determined by archaeomagnetic measurements of 734 oriented samples, collected from baked earths of remains in the southern Korea. These data cover periods of A.D. 39C, A.D. 1317 and A.D. 15-l6C. It is noted that Korean geomagnetic field data in 5-6C arc similar to those of contemporary Japanese geomagnetic field, but Korean geomagnetic field data in A.D. 3-4C deflect more easterly than contemporary Japanese geomagnetic field. The observed large difference of geomagnetic field direction between Korea and Japan suggests the existence of a prominent local geomagnetic anomaly in the vicinity of Japan and Korea in the period of A.D. 3-4C. An approximate figure of Korean archaeomagnetic secular curve for the periods of A.D. 3-6C and A.D. 7-9C was obtained. This curve is sure to be helpful for Korean archaeology to data the last firing of baked earths accompanied with no relics.

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Epidemiological Investigations to Optimize the Management of Pepper Anthracnose

  • Ahn, Mun-Il;Yun, Sung-Chul
    • The Plant Pathology Journal
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    • v.25 no.3
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    • pp.213-219
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    • 2009
  • An understanding of anthracnose (Colletotrichum acutatum) infections, including the infection of flowers and latent infection early in the season, is necessary to achieve successful control by means of properly timed spraying with a curative fungicide. In the present study, latent anthracnose infection of chili was investigated under greenhouse and field conditions in 2007-2008. Flowers on greenhouse-grown seedlings were infected and 11% of the young fruits subsequently showed symptoms of anthracnose. Apparently healthy-looking green peppers obtained from unsprayed fields or an organic market also exhibited symptoms of anthracnose after 4 days of incubation under high moisture conditions at $25^{\circ}C$; less than 1% of the peppers were found to be latently infected. To determine the natural timing of infection in the field, 3,200 fruits were wrapped in paper bags and then selectively unwrapped and examined for signs of infection. Field experiments were conducted at Suwon (cvs. Yokkang, Manitta, Olympic) and Asan (cv. Chunhasangsa) in 2008. The 7- to 10-day wrapping periods were July 25-31, July 31-August 7, August 7-15, August 15-24, and August 24-September 3. The 1-to 2-month wrapping periods were from July 4, July 31, and August 15 until harvest (Sept. 3). The controls consisted of 1,712 field-grown non-wrapped fruits. The rates of infection on the various cultivars were Yokkang 55%, Manitta 37%, Olympic 55%, and Chunhasangsa 20%. A distinct period in which anthracnose infection suddenly increased could not be identified; however, attempts to guess the approximate timing of field infection showed that 0-39% of the plants had latent infections, while depending on the cultivar, 8-14% of the plants examined in August and 4-13.5% of the those examined during May-July showed symptoms of infection. Delaying fungicide spraying by 24 and 48 h after artificial infection decreased the rates of infection by 10% and 25-30%, respectively. Chemical control of anthracnose based on a forecasting model should be considered starting from the transplanting stage, with spraying within a day after warning and care being taken not to latently infect apparently healthy pepper fruits.

A Possibility for Multilateral CDM Projects in Northeast Asia - The reduction effect in transaction cost by Korean participation - (동북아시아지역의 다국 간 CDM프로젝트에 대한 검토 -한국 참가에 따른 거래비용 삭감효과-)

  • Jung, Woo-Jong;Nakano, Satoshi
    • Journal of Environmental Policy
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    • v.2 no.2
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    • pp.41-63
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    • 2003
  • CDM(Clean Development Mechanism) project is said to be a mechanism, which profits both the investing country and the host country, while additionally contributing to the reduction of greenhouse gases of the earth as a whole. However in reality, most of the proposed projects do not end up in agreement because of the problems related to differences in recognition between the investing country and the host country of the CDM project. This outlines the background for this research which proposes a new design of institutional arrangements of CDM projects in the Northeast Asian region, mainly Japan, China and Korea. In addition, we investigate the feasibility of the proposed design. The research firstly focuses on the reduction in transaction costs that the participation of Korea will have on a Japan-China CDM project. This paper further emphasizes the potential gains that would materialize if a CDM project involved the whole Northeast Asian region, and not only one country. Our research suggests that an approximate reduction of 23% in transaction costs, and about 4% reduction in the total costs of a CDM project can be expected to follow the Korean participation. In addition to decreasing costs we find that a Korean involvement in a CDM project with Japan will lead to efficiency gains illustrated by a higher increase in the IRR(Internal rate of return) in a Japan-Korea project(11.45% to 12.21%) compared to an IRR incresement of 10.57% to 11.27% for a pure Japanese CDM project. Similar results of a rise in the IRR is found for the whole investment period of 20 years. We can hence conclude that Korean participation in a Japan-China CDM project would improve the implementation possibilities of CDM project in the Northeast Asia region.

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