• 대한기계학회논문집
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• 제18권12호
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• pp.3159-3174
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• 1994

A simple octree encoding algorithm based on a tetrahedron root has been developed to be used for fully automatic generation of three dimensional finite element meshes. This algorithm starts octree decomposition from a tetrahedron root node instead of a hexahedron root node so that the terminal mode has the same topology as the final tetrahedral mesh. As a result, the terminal octant can be used as a tetrahedral finite element without transforming its topology. In this part(I) of the thesis, an efficient algorithm for the tetrahedron-based octree is proposed. For this development, the following problems have been solved, : (1) an efficient data structure for storing the octree and finite elements, (2) an encoding scheme of a tetrahedral octree, (3) a neighbor finding technique for the tetrahedron-based octree.

• Journal of Plant Biology
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• 제30권4호
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• pp.249-255
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• 1987

The effect of polyamine and Ca2+ on D-glucose-6-phosphate cyclohydrolase activity was studied in Daucus carota root. The enzyme activity was reduced in response to increase in concentration of Ca2+, not the Ca2+-calmodulin complex. The inhibition effect due to Ca2+ was reversed by polyamine, especially remarkable at low concentration of Ca2+. The effect of the Ca2+ on the enzyme seemed to compete with polyamine according to the Lineweaver-Burk plot. The enzyme activity from carrot root protoplast cultured in the prescence of verapamil was higher than that of the control. Such cumulative results suggest that the inhibition by the Ca2+ and enhancement or reversal by polyamine could regulate the biosynthesis of pectin and hemicellulose to some extent.

• The Plant Pathology Journal
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• 제36권3호
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• pp.297-302
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• 2020

Root-knot nematodes (Meloidogyne spp.) are the most destructive group of plant-parasitic nematodes. Plants infected by Meloidogyne spp. develop above-ground symptoms, stunting, yellowing, nutrient deficiencies, and gall formations with typical hook-shaped root tips. Infected plants experience yield losses. During 2018-2019 survey, leaf chlorosis rice plants were found in 206 fields of 67 counties in Guangxi, China, around 30 days after transplanting. Galls and hooked tips on the roots and pear-shaped females were observed. About 32.04% of fields were infested with the nematode. The nematodes were identified as Meloidogyne graminicola base on morphological and molecular analysis. To the best of our knowledge, this is the first report of M. graminicola on rice plants in Guangxi, China. The results of this study urge the discovery of resistant cultivars and the development of management strategies.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.553-553
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• 2003

I. Objectives Endodontic disease is caused primarily by bacteria that interact with periradicular host from the root canal system. Chlorhexidine gluconate is known to effective to eliminate Enterococcus faecalis which resists to other intracanal medicaments. The aim of this in vitro study was to develop a slowly releasing root canal disinfectant using using chlorhexidine gluconate and chitoic acid. II. Materials and Methods Three different group were prepared with different drug release mechanism. In group A, paper points as used core material were loaded with 20% chlorhexidine gluconate.(omitted)

• 한국위험물학회지
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• 제6권2호
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• pp.47-54
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• 2018

Mixed acid is very reactive and highly corrosive. it has been causing many accidents in a electronic industry, a steel industry, and a chemical industry. Therefore, it is required that the high safety level for the acid storage facilities. In this study, we investigated the accident causes for resent leak accidents with Root Cause Analysis (RCA). The root causes analysed by RCA were categorized as nine divisions by the their characteristics. Furthermore, each nine divisions causes was applied to the PDCA model which are using at OHSAS 18001. It is suggested that the nine division with the root causes can be the essential items for the development of the safety management manual. It is helpful to the safety improvement of the acid storage facility.

• 한국산림과학회지
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• 제89권5호
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• pp.677-684
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• 2000

본 연구는 토양 특성이 다른 30-40년생 독일가문비나무(Picea abies [L.] KARST) 임분에서 토양 깊이에 따른 뿌리구조 분석을 통하여 뿌리 발달의 차이점과 토양 상태의 상호관계 및 외부 형태적 특징 그리고 기계적 물리적 안정성에 대한 적응범위를 밝히고자 실시하였다. 조사된 3개 임분에 있어서 독일가문비나무의 뿌리구조는 다양한 형태로 관찰되었는데, Eberg$\ddot{o}$tzen 임분은 뿌리수가 많고 가늘며 토양 깊이까지 발달한 뿌리구조를 보였으며, Barbis 임분은 Eberg$\ddot{o}$tzen 임분에 비하여 그 수가 적으나 굵고 깊이까지 자라는 뿌리구조를 나타내었다. 그리고 Weidenbrunnen 임분은 반 수직 뿌리와 편평/접시형 뿌리구조를 나타내었다. 뿌리의 수는 Eberg$\ddot{o}$tzen 임분이 74개로 가장 많은 뿌리 수를 보여주었으며, Barbis 임분은 33개, Weidenbrunnen 임분은 57개이었다. Eberg$\ddot{o}$tzen 임분은 수직뿌리에서 평균 57개로 Barbis 임분이 21개이고, Weidenbrunnen 임분 36개에 비하여 월등히 많은 뿌리의 수를 나타내었다. 뿌리의 길이는 Weidenbrunnen 염분이 전체 뿌리길이가 다른 두 임분에 비하여 길게 나타났으며, 수형뿌리의 길이는 수직뿌리에 비하여 그 값이 107m로 매우 큰 값을 나타내었다. 수직뿌리에 대한 수평뿌리의 비는 Eberg$\ddot{o}$tzen 임분이 다른 두 임분(0.5)에 비하여 그 값이 1.2로 높게 나타났다. 전체 뿌리무게는 다른 두 임분에 비하여 Weidenbrunnen 임분이 매우 높은 값을 보여 주였으며, 수명뿌리에 대한 수직뿌리의 비는 0.16으로 다른 두 임분(0.40)에 비해 매우 낮은 값을 나타내었다. 본 연구의 독일가문비나무 임분에서 나타난 뿌리 발달의 현저한 차이점은 토양의 기계적 물리적 요인보다는 토양 산성화와 같은 화학적인 요인으로 인하여 정상적인 뿌리의 발달이 장애를 받아 수직뿌리생장이 저하되고 수분과 영양분의 스트레스로 언하여 상대적으로 수평뿌리가 발달된 결과로 사료된다.

• 농약과학회지
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• 제18권4호
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• pp.439-442
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• 2014

신나밀계 화합물은 다양한 생물에 넓게 분포하는 생물 2차대사산물로 잘 알려져 있으며, 여러 생리활성이 규명되었다. 하지만, 작물의 생장조절기능성 연구결과는 잘 알려져 있지 않아, 본 연구에서는 신나밀기를 갖는 acid, amide, alcohol, aldehyde, ester등 46종의 유도체를 대상으로 발아와 유근생장억제능을 비교평가 하였다. 시험 결과, cinnamyl group을 기본 골격으로 하는 화합물의 경우 carboxylic acid group보다는 ester, amide, aldehyde와 같은 functional group에서 유근생장 억제능이 쉽게 관찰되는 것으로 확인되었다. 또한, EWG는 meta-position에 위치할 때 가장 효과가 높은 것으로 확인되었으며, cinnamamide, 3-chlorocinnamic acid와 4-methoxycinnamaldehyde는 100 mg/L 미만의 처리농도에서 배추에 대한 발아억제를 일으키지 않으며, 유근생장 생장억제기능성이 높아 작물 생장억제제로 사용가능한 cinnamyl 유도체임을 확인하였다.

• Food Science and Biotechnology
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• 제16권2호
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• pp.238-242
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• 2007

Square root models were developed for predicting the kinetics of growth of Listeria monocytogenes in sesame leaves as a function of temperature (4, 10, or $25^{\circ}C$). At these storage temperatures, the primary growth curves fit well ($R^2=0.898$ to 0.980) to a Gompertz equation to obtain lag time (LT) and specific growth rate (SGR). The square root models for natural logarithm transformations of the LT and SGR as a function of temperature were obtained by SAS's regression analysis. As storage temperature ($4-25^{\circ}C$) decreased, LT increased and SGR decreased, respectively. Square root models were identified as appropriate secondary models for LT and SGR on the basis of most statistical indices such as coefficient determination ($R^2=0.961$ for LT, 0.988 for SGR), mean square error (MSE=0.l97 for LT, 0.005 for SGR), and accuracy factor ($A_f=1.356$ for LT, 1.251 for SGR) although the model for LT was partially not appropriate as a secondary model due to the high value of bias factor ($B_f=1.572$). In general, our secondary model supported predictions of the effects of temperature on both LT and SGR for L. monocytogenes in sesame leaves.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.17-17
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• 2018

Panax ginseng Meyer is a perennial medicinal plant, the roots of which has been used in the traditional formulations in Oriental countries. To understand its floral transition, we isolated Flowering Locus T (FT) from ginseng, the bioinformatics analysis of PgFT has revealed a considerable homology to the higher plants, with the essential amino acids for FT function are conserved. The phylogenetic analysis has shown that the PgFT is belonged to the shrub classes of plants and closest kin to Jatropha curcas FT. The expression profiling from juvenile (2-year-old) were abundant in leaves as well as in root and was concentrated in the secondary leaflet and stem bottom in adult (4-year-old) ginseng plant tissues, moreover PgFT transcript displayed photoperiod dependent oscillation. The ectopic expression of PgFT in Arabidopsis thaliana, exhibit precocious flowering and several floral pathway integrators were up-regulated, interestingly their root length was increased in the transgenic seedlings. Therefore, we could conclude that PgFT encodes a florigen that acts as a key regulator in the flowering pathway in ginseng and hypothesize that, it might involve in the underground organ development as well. We believe our finding could provoke future studies on the physiology and development in P. ginseng.

• 한국산학기술학회논문지
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• 제10권3호
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• pp.607-612
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• 2009

생태방음벽에 있어서 구조도 중요하지만, 식물종자의 발아와 생장율을 고려한 선택도 매우 중요하다. 재래종과 외래종 35종을 선발하여 온도 $24^{\circ}C$, 습도 60%, 그리고 12시간 주기로 낮과 밤을 조절하였고, 식생기반재로 일반토양과 유기물 토양의 비율을 6:4, 7:3, 8:2, 9:1로 하여 실험하였다. 실험한 종 중 8종은 2주 동안 발아하지 않았지만 그 외 나머지 종들은 시간차를 두고 모두 발아하였다. 가장 발아율이 좋은 종은 Perennial penant(92 %)이고 다음은 Brassica napus(86%), 그리고 Silene armeria(82 %) 순으로 나타났다. 본 연구에서는 발아한 종의 뿌리 및 줄기의 길이를 측정하여 분석하였다. 이번 연구에서 뿌리의 생장이 가장 좋은 3종 Perennial penant, Perennial sonata Rebolsentri가 생태방음벽 개발에 가장 적합한 종으로 사료된다.