• Korea-Australia Rheology Journal
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• 제12권1호
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• pp.69-76
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• 2000

We have derived the translation diffusion coefficient and the intrinsic viscosity formula adopting the Kholodenko's theory using 3＋1 dimensional Dirac propagator in the Kirkwood and Riseman scheme. We also performed static light scattering experiments and intrinsic viscosity measurement of dilute solutions of polyimides with different rigidities. In the framework of Kholodenko's theory, we can easily measure the persistence length of polyimide. We prepared five different polyamic acids and polyimides with different degree of imidization by controlling imidization temperatures. From experimental results, we obtained molecular weights and persistence lengths according to the Kholodenko's plot. The molecular weight and the intrinsic viscosity decreased and then increased with the imidization temperature but the persistence length increased monotonically and then leveled off. The persistence lengths calculated from intrinsic viscosities showed very good agreement with those from light scattering experiments.

• ALGAE
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• 제37권1호
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• pp.63-74
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• 2022

Perennial stipitate kelps are globally distributed and individual species can inhabit broad latitudinal ranges, expressing notably longevous persistence. Despite the foundational role kelps provide to their communities, little is known about the variability in persistence of the stipitate kelps at local spatial scales. We studied the population persistence of Eisenia arborea, a heat- and wave force-tolerant perennial stipitate kelp with a distributional range extending from British Columbia to south of the range limit of all other northeast Pacific kelps, in Baja California Sur, Mexico. Persistence characteristics for E. arborea among sites were compared and used to test the hypothesis that stand persistence varied at local spatial scales around Isla Natividad, a Pacific island off the Baja California peninsula with documented spatiotemporal environmental heterogeneity. Collected individuals around the island were "aged" using the previously validated age estimation technique of counting annual cortical dark rings. After detecting no significant differences among sites in the covariation between estimated ages for collected individuals and stipe length, we utilized in-situ population-level stipe length measurements to more rapidly predict age structures within six stands around the island. Predicted age structures, and associated stand densities, revealed persistence characteristics and density varied at local scales and a strong positive relationship existed between stand density and stand mean and maximum ages. We speculate that stands responded differently to deterministic influences (e.g., the 2014-2016 marine heatwave and / or competition with Macrocystis) resulting in heterogenous local persistence of this foundation species.

• 터널과지하공간
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• 제8권4호
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• pp.351-358
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• 1998

현장에서 측정된 절리 trace 길이에 의거하여 영속성을 산정할 수 있는 통계적 분석법을 개발하였다. 이 방법에서는 잠재적 키블록과 불연속면의 상대적인 규모에 따라 절리 trace 기링 또는 원형절리의 직경에 대한 확률밀도분포를 이용한다. 대규모 지하공동의 설계 및 안전적 굴착에 대한 개발된 분석법의 활용성을 설명하기 위하여 규모 및 영속성이 다른 잠재적 키블록의 안정성을 고찰하였다.

• 한국정보과학회논문지:시스템및이론
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• 제26권8호
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• pp.1009-1023
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• 1999

이 논문은 재귀원형군 G(2^m , 2^k ) 그래프 이론적 관점에서 고찰하고 정점이 서로소인 경로에 관한 위상 특성을 제시한다. 재귀원형군은 1 에서 제안된 다중 컴퓨터의 연결망 구조이다. 재귀원형군 {{{{G(2^m , 2^k )의 서로 다른 두 노드 v와 w를 잇는 연결도 kappa(G)개의 서로소인 경로의 길이가 두 노드 사이의 거리d(v,w)나 혹은 G(2^m , 2^k )의 지름 \dia(G)에 비해서 얼마나 늘어나는지를 고려한다. 서로소인 경로를 재귀적으로 설계하는데, 그 길이는 k ge2일 때 d(v,w)+2^k-1과 \dia(G)+2^k-1의 최솟값 이하이고, k=1일 때 d(v,w)+3과 \dia(G)\+2의 최솟값 이하이다. 이 연구는 (2^m , 2^k )의 고장 감내 라우팅, 고장 지름이나 persistence의 분석에 이용할 수 있다.Abstract In this paper, we investigate recursive circulant G(2^m , 2^k ) from the graph theory point of view and present topological properties concerned with node-disjoint paths. Recursive circulant is an interconnection structure for multicomputer networks proposed in 1 . We consider the length increments of {{{{kappa(G)disjoint paths joining arbitrary two nodes v and win G(2^m , 2^k )compared with distance d(v,w)between the two nodes and diameter {{{{\dia(G)of G(2^m , 2^k ), where kappa(G)is the connectivity of G(2^m , 2^k ). We recursively construct disjoint paths of length less than or equal to the minimum of {{{{d(v,w)+2^k-1and \dia(G)+2^k-1for kge2 and the minimum of d(v,w)+3 and \dia(G)+2for k=1. This work can be applied to fault-tolerant routing and analysis of fault diameter and persistence of G(2^m , 2^k )

• 한국작물학회지
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• 제40권2호
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• pp.221-227
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• 1995

초지에서 white clover의 존속과 우점 모두가 문제시 되고 있다. 본시험은 white clover의 방목방법에 대한 정보를 제공하기 위하여 예취적기의 장?단(1주, 4주)과 이들의 교호가 white clover의 예취수량 및 형태적 특성에 미치는 영향과 이들간의 관계를 구명하고자 pot 시험으로 실시하였던바 그 결과를 요약하면 다음과 같다. 1. 예취적기 4적에 비하여 1적에서는 예취수량 및 주당엽면적과 엽수, 엽병장, 주당포복경장이 감소되나 g당포복경장과 Specific Leaf Area는 증가되었다. 2. 예취적기 1적와 4적를 교호할 경우 예취수량은 1적 또는 4적로 계속예취한 것의 중간정도이었으나 초기에 4적로 예취한 것에서 높은 수량을 보였다. 3. 예취적기를 교호할 경우 잎과 관련한 형질은 예취적기의 장단에 따라 변하였으나 포복경과 관련된 형질은 교호전 예취적기의 영향이 비교적 장기간 지속되었다. 4. 예취적기를 교호할 경우 예취수량은 주당 엽면적, 엽수 및 포복경장과 정의 상관을. SLA와 g당포복경장과는 부의 상관을 보였다.

• ALGAE
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• 제33권1호
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• pp.101-108
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• 2018

Saccharina japonica was introduced to both Korea and China from Hokkaido, Japan, and it has become an economically important species in both nations. After a long period of cultivation, several varieties of S. japonica have been developed in Korea and China. In this study, we conducted aquacultural research on the persistence of thalli from two kelp cultivars, one from China (Huangguan No. 1) and one from Korea (Sugwawon No. 301), between December 2015 and November 2016 in Haenam, Korea. The maximum length was $247.8{\pm}13.0$ and $227.5{\pm}42.0cm$, respectively, which were significantly longer in Sugwawon No. 301 than in Huangguan No. 1. The maximum width was $29.9{\pm}5.4$ and $23.2{\pm}1.9cm$, respectively, which were significantly wider in Huangguan No. 1 than in Sugwawon No. 301. The mean biomass obtained from the culture ropes was for Sugwawon No. 301 was $3.5{\pm}0.3kg\;wet\;wt\;m^{-1}$ and for while Huangguan No. 1 was $3.1{\pm}1.0kg\;wet\;wt\;m^{-1}$ of culture rope. After August, the persistence of the thalli of Sugwawon No. 301 was two months longer than that of Huangguan No. 1. We found that the Sugwawon No. 301 performed as well as the Huangguan No. 1 in Korean waters possibly due to increased flexibility as a result of the different cell arrangements of the two cultivars. Overall, the use of the Sugwawon No. 301 cultivar rather than the Huangguan No. 1 cultivar of S. japonica appears the best alternative to help to ensure a stable year round algal feed supply for the Korean abalone industry.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1998년도 가을 학술발표회논문집
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• pp.94-97
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• 1998

We have been studying :he synthesis of thermotropic polyurethanes, based on structural modifications by means of (i) the introduction of bulky substituent group in the aromatic ring to decrease the degree of lateral packing, (ii) the copolymerization of two kinds of monomers having different alkylene lengths to lower the regularity of the polymer structure, and (iii) the use of nonlinear monomers to lower the persistence length of the polymer chain in the liquid crystalline phase and to decrease the lateral interactions in the solid state. (omitted)

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.67-67
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• 2003

Filamentous actin (F-actin) is a two stranded long helix that performs structural function in eukaryotic cells. F-actin had been assembled from Alexa-labeled G-actin and had been confined in microchannel. The fluctuation of single filaments was observed by fluorescence optical microscopy. We measured Tangent-tangent Correlation Function G(s) (where s is the distance along the contour of the chain), which tells us the confining wall effect of wormlike semi-flexible polymers as well as the flexural rigidity, such as persistence length.

• Molecules and Cells
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• 제45권1호
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• pp.33-40
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• 2022

The various DNA-protein interactions associated with the expression of genetic information involve double-stranded DNA (dsDNA) bending. Due to the importance of the formation of the dsDNA bending structure, dsDNA bending properties have long been investigated in the biophysics field. Conventionally, DNA bendability is characterized by innate averaging data from bulk experiments. The advent of single-molecule methods, such as atomic force microscopy, optical and magnetic tweezers, tethered particle motion, and single-molecule fluorescence resonance energy transfer measurement, has provided valuable tools to investigate not only the static structures but also the dynamic properties of bent dsDNA. Here, we reviewed the single-molecule methods that have been used for investigating dsDNA bendability and new findings related to dsDNA bending. Single-molecule approaches are promising tools for revealing the unknown properties of dsDNA related to its bending, particularly in cells.

• 한국토양비료학회지
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• 제33권3호
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• pp.167-174
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• 2000

본 연구는 2년간('97~'98) 벼 2모작 재배시 질소시용량별 보릿짚의 분해정도(分解程度)와 벼 생육(生育) 및 수량성(收量性) 변이(變異)를 조사하기 위하여 전북통(全北統)에서 시험한 결과는 다음과 같다. 보릿짚의 탄소잔존률(炭素殘存率)은 질소시 용량이 많을수록 적어졌으나 질소잔존률(窒素殘存率)은 증가하였고 C/N율(率)은 낮아졌다. 보릿짚시용시 토양미생물(土壤微生物)은 방사선(放線菌)>셀룰로오스분해균(分解菌)>세균(細菌)>사상균(絲狀菌) 순으로 많았다. 보릿짚시용에 의한 질소기아현상(窒素飢餓現象)은 분얼기(分蘖期)에 나타났으나 질소 $144kg\;ha^{-1}$시용구에서는 나타나지 않았다. 보릿짚시용으로 초장(草長), 간장(稈長), 수장(穗長)이 짧아졌으나 질소 $103kg\;ha^{-1}$ 시용구에서는 보릿짚무시용과 큰차이가 없었다. 보릿짚시용시 쌀수량(收量)은 질소 $108kg\;ha^{-1}$ 시용구에서 보릿짚무시용구와 같았으며 질소 90, $144kg\;ha^{-1}$ 시용구에서는 보릿짚무시용구(無施用區) 대비(對比) 감소폭(減少幅)이 컸다.