• Steel and Composite Structures
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• 제21권5호
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• pp.981-997
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• 2016

To avoid the cracks of cast-in-place concrete in shear pockets and seams in the traditional composite beam with precast decks, this paper proposed a new type of prefabricated steel truss-concrete composite beam (ab. PSTC beam) with pre-embedded shear studs (ab. PSS connector). To study the initial cracking load of concrete deck, the development and distribution laws of the cracks, 3 PSTC beams were tested under hogging moment. And the crack behavior of the deck was compared with traditional precast composite beam, which was assembled by shear pockets and cast-in-place joints. Results show that: (i) the initial crack appears on the deck, thus avoid the appearance of the cracks in the traditional shear pockets; (ii) the crack of the seam appears later than that of the deck, which verifies the reliability of epoxy cement mortar seam, thus solves the complex structure and easily crack behavior of the traditional cast-in-place joints; (iii) the development and the distribution laws of the cracks in PSTC beam are different from the conventional composite beam. Therefore, in the deduction of crack calculation theory, all the above factors should be considered.

• Mycobiology
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• 제29권2호
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• pp.80-84
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• 2001

Nine species of genus Ganoderma different in cultural characteristics each other were separated by histo-anatomical differences. Differences among the species and geographic distribution of G. lucidum were also analyzed to provide the criteria for the classification of Korean cultivation or wild type strains. Korean cultivation and wild type strains were quiet different from other species as well as Taiwan and North American G. lucidum strains in histo-anatomical traits of Ganoderma. Pore color of Korean G. lucidum strains was less brown than those of Taiwan and North American strains. Shapes of pores were round or circular in Korean strains but ellipsoidal or angular in Taiwan or North American strains. Pore numbers of Korean strains were more than those($4{\sim}6/mm$) of Taiwan or North American strains. Hardness of the pileus of Korean strains was much more than that of Taiwan or North American strains. Such characteristics of Korean strains were different from those of other species of Ganoderma. Korean G. lucidum strains could be classified into the other group because they had many different traits in growth characteristics of fruiting bodies and histo-anatomical characteristics from those of Taiwan or North American G. lucidum and other species of G. lucidum complex.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.300-306
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• 2000

This paper introduces a new concept of automation for bio-production with tele-operative system. The proposed system showed practical and feasible way of automation for the volatile bio-production process. Based on the proposition, recognition of the job environment with object identification was performed using computer vision system. A man-machine interactive hybrid decision-making, which utilized a concept of tele-operation was proposed to overcome limitations of the capability of computer in image processing and feature extraction from the complex environment image. Identifying watermelons from the outdoor scene of the cultivation field was selected to realize the proposed concept. Identifying watermelon from the camera image of the outdoor cultivation field is very difficult because of the ambiguity among stems, leaves, shades, and especially fruits covered partly by leaves or stems. The analog signal of the outdoor image was captured and transmitted wireless to the host computer by R.F module. The localized window was formed from the outdoor image by pointing to the touch screen. And then a sequence of algorithms to identify the location and size of the watermelon was performed with the local window image. The effect of the light reflectance of fruits, stems, ground, and leaves were also investigated.

• Plant Resources
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• 제3권3호
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• pp.226-232
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• 2000

The availability of enokitake cultural waste for Lentinus edodes cultivation was investigated, although hardwood sawdust has traditionally been used as a substrate for this fungus. Firstly, physiochemical characteristics of cultural waste were analysed. Secondly, mycelial growth characteristics and fruiting yields of L. edodes on waste treated in some methods were determined. Physiochemical characteristics of enokitake cultural waste showed that the millwaste complex was a little degraded by enokitake fungus and suggested the probability that most component lost by enokitake could be rice bran. Mycelia of L. edodes grew and fruited well on waste supplemented by fresh rice bran and Quercus sawdust although didn't on waste only. Mycelial growths of these fungi on waste were accelerated when supplemented by rice bran to the percent of 40(w/w) but decreased or suppressed at above ratios(30, 40%, w/w). Supplementations of oak sawdust at above 40%(w/w) of the waste and rice bran at 20%(w/w) of the sawdust allowed such a good mycelial growth as to be selected as a pertinent mixing ratio for fruiting medium. A fruiting yield on enokitake cultural waste supplemented by oak sawdust (at 40% of the waste, w/w) and rice bran (at 20% of the sawdust, w/w) was not inferior to that on oak sawdust supplemented by rice bran only (at 20% of the sawdust, w/w). These results indicated strongly the potentiality of enokitake cultural waste as raw materials for shiitake cultivating substrates.

• Journal of Ginseng Research
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• 제43권1호
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• pp.1-9
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• 2019

Background: Korean ginseng is an important cash crop in Asian countries. However, plant yield is reduced by pathogens. Among the Ilyonectria radicicola-species complex, I. mors-panacis is responsible for root-rot and replant failure of ginseng in Asia. The development of new methods to reveal the existence of the pathogen before cultivation is started is essential. Therefore, a quantitative real-time polymerase chain reaction method was developed to detect and quantify the pathogen in ginseng soils. Methods: In this study, a species-specific histone H3 primer set was developed for the quantification of I. mors-panacis. The primer set was used on DNA from other microbes to evaluate its sensitivity and selectivity for I. mors-panacis DNA. Sterilized soil samples artificially infected with the pathogen at different concentrations were used to evaluate the ability of the primer set to detect the pathogen population in the soil DNA. Finally, the pathogen was quantified in many natural soil samples. Results: The designed primer set was found to be sensitive and selective for I. mors-panacis DNA. In artificially infected sterilized soil samples, using quantitative real-time polymerase chain reaction the estimated amount of template was positively correlated with the pathogen concentration in soil samples ($R^2=0.95$), disease severity index ($R^2=0.99$), and colony-forming units ($R^2=0.87$). In natural soils, the pathogen was recorded in most fields producing bad yields at a range of $5.82{\pm}2.35pg/g$ to $892.34{\pm}103.70pg/g$ of soil. Conclusion: According to these results, the proposed primer set is applicable for estimating soil quality before ginseng cultivation. This will contribute to disease management and crop protection in the future.

• 한국버섯학회지
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• 제20권3호
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• pp.183-185
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• 2022

여름철 버섯소비 부진으로 일부 농가에서는 여름철에 생산을 중단하는 등, 고소득 버섯작목 복합영농의 필요성이 제기됨에 따라, 녹각영지버섯을 새송이버섯 재배사를 이용하여 생산 가능 여부를 확인하고자 시험을 실시하였다. 배지재료로 사용한 참나무톱밥과 미강의 화학적 특성을 조사한 결과 T-N은 주재료인 참나무톱밥이 0.28%, 영양원인 미강이 2.2%로 나타났으며, pH는 참나무톱밥 6.0, 미강 6.6로 주재료인 참나무톱밥은 약산성을 나타내었고, 영양원인 미강은 중성을 나타내었다. 녹각영지버섯 자실체 수량특성을 조사한 결과, 초발이 소요일수는 25℃ 5~6일, 30℃ 3~5일이었으며, 대의 길이는 25℃에서 57.5 mm, 30℃에서 92.2 mm였고, 생체중은 25℃에서 43g, 30℃에서 50 g으로 30℃에서 우수하였다. 본 시험을 통하여 하절기에 새송이버섯 재배사를 녹각영지버섯 재배에 활용이 가능함을 확인하였다.

• 한국기후변화학회지
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• 제3권2호
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• pp.129-142
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• 2012

본 연구는 벼 생산에 필요한 농자재의 제조와 벼 재배과정 그리고 농자재의 폐기과정에서 발생되는 탄소성적을 산정하고, 주요한 온실가스인 메탄의 발생 저감을 위한 재배기술을 비교평가하기 위해 수행되었다. 벼 생산 단계에서 탄소 발생량은 투입된 농자재의 물량을 기준으로 농자재와 에너지의 제조단계에서 탄소발생량, 농작물 생육 단계에서는 시비질소 유래 아산화질소 발생량과 에너지 소비에 탄소 발생량, 농법에 따른 메탄발생량 그리고 농자재의 폐기에 따른 탄소발생량의 합으로 산정할 수 있다. 벼 1 kg 생산 단계에서 발생되는 이산화탄소는 1.40 kg이었으며, 발생된 온실가스 배출비율은 벼 생육 단계에서 메탄 유래 탄소발생량이 71.1%로 가장 많았고, 다음으로 시용된 질소에 의한 아산화질소 유래 탄소발생량이 11.8%였으며, 복합비료 제조단계에서 발생된 탄소발생량이 7.6%에 달하였다. 벼 재배기술 별 메탄 발생량을 비교한 결과, 중만생종 대비 조생종 품종재배로 44.4%, 늘 물대기 대비 중간 물떼기로 43.8%, 암거배수처리로 38.7%, 이앙재배 대비 직파재배로 32.0%, 경운 대비 무경운 재배로 20.9%의 감축 효과가 있는 것으로 나타났다. 향후 전과정 지구온난화 평가방법을 이용하여 온실가스 감축 실적의 측정-보고-검증 체계 구축이 필요하며, 이는 탄소배출권 거래제나 저탄소농산물 인증제의 과학적 근거를 제시하는 데 기여할 것이다.

• 한국약용작물학회지
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• 제26권4호
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• pp.302-307
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• 2018

Background: A soil-borne pathogenic fungus, Ilyonectria radicicola (Cylindrocarpon destructans) causes root rot on ginseng (Panax ginseng C. A. Meyer) and is known to attack many other plants. The Nectria/Neonectria radicicola complex has been renamed as the I. radicicola complex after analysis of its multi-gene relatedness and morphological characteristics. The fungi in this complex have been reclassified into 16 species under the genus Ilyonectria based on characteristics analysis Methods and Results: To obtain useful data from the Korean ginseng root rot, I. radicicola was isolated from the rhizosphere soils of the chestnut tree. They were identified through a pathogenicity test and a survey of the morphological features. The existence of I. radicicola in soil samples was confirmed by PCR detections using nested PCR with species-specific primer sets. These were subsequenctly isolated on semi-selective media from PCR-positive soils. Genetic analysis of the I. radicicola complex containing these pathogens was done by comparing the DNA sequences of the histone h3 region. These isolates originating from the rhizosphere soils of chestnut constituted a clade with other closely related species or I. radicicola isolates originating from ginseng or other host plants, respectively. Additionally, the pathogenicity tests to analyze the characteristics of these I. radicicola isolates revealed that they caused weakly virulent root rot on ginseng. Conclusions: This is the first study reporting that I. radicicola isolates from chestnut rhizosphere soils can attack ginseng plant in Korea. Thus, these results are expected to provide informations in the selection of suitable fields for ginseng cultivation.

• 한국전자거래학회지
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• 제18권2호
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• pp.175-189
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• 2013

농산물의 수입개방으로 질이 낮은 수입 농산물이 국산으로 둔갑하여 소비자의 신뢰가 낮아지고 있으며, 국산 농산물의 가격 경쟁력이 지속적으로 하락하고 있는 실정이다. 이러한 위기 상황에서 국산 농산물의 원산지에 대한 신뢰도를 높이고 아시아의 주식이지만 여전히 기술이 낙후되어 있는 미곡 산업에서도 이러한 첨단 기술을 적용하고자 하는 노력이 진행중이나 아직도 미흡한 실정이다. 나아가, 기존의 농산물 생산이력시스템은 기초적인 이력정보만 제공하고 있으며, 미곡종합처리장의 경우에 경험적인 수확시기 결정으로 인해 일시에 수확이 몰리는 홍수반입이 발생하여 미곡의 품질 손상이 빈번히 발생하기도 한다. 본 논문에서는 스마트 기기와 GIS/LBS, RFID 등의 유비쿼터스 기술을 적용하여 유비쿼터스 벼 생산 및 반입 관리 시스템을 개발하였다. 기존에 수기로 작성하던 농가 및 농지 정보를 스마트 기기로 입력하고, 재배단계에서의 품질 모니터링을 제공하며, 수집된 생산, 재배, 품질정보를 스마트 기기를 통하여 제공한다. 데이터베이스를 기반으로 하여 품질에 따른 반입시기를 결정하는 과학적인 반입체계를 구축하고, 농가와 유통업자, 소비자간의 신뢰도를 높이고자 한다.

• 한국미생물·생명공학회지
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• 제28권6호
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• pp.341-348
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• 2000

Selection of high producer strain, optimization of production medium and cultivation in bioreactor system were carried out in order to produce an antifungal substance, PAFS in large amounts which sources and 41 kinds of nitrogen sources, a synthetic medium consisting of fructose(70 g/1) and ammonium sulfate (10g/l) and a complex medium including galactose(30g/l), fructose(20g/l) and cottonseed flour(35g/l) were determined as opti-mized media for PAFS production. In bioreactor studies examining physiological characteristics of the pro- ducer microorganism with the complex medium, typical pattern of diauxic growth was observed as demonstrated by the result that fructose was not used before almost exhaustion on readily utilizable carbon source, galactose. When galactose was supplemented additionally during the fermentation period. PAFS pro-ductivity did no increases any more, indicating that large portion of the added galactose was used for cell growth instead of biosynthesis of the secondary metabolite. It was deduced that PAFS production could be enhananced by employing fed-batch operation in order to overcome the apparent phenomenon of catabolite repression and /or inhibition.