• The Korean Journal of Ecology
• /
• 제6권4호
• /
• pp.1-9
• /
• 1983

The observation of branching pattern on Magnolia denudata Desr. was performed from July 1982 to September 1983 and then computer simulation was carried out. Tree crown pattern depends on not genetic factors but also environmental factors and the determination of branchin pattern which characterized it appears to properly explain the relationships such as branching pattern and allocation of materials through the analysis of influence branches under several assumptions. Now that computer simulated simulated pattern was considered as the accumulation of two factors which controled the growth, it was represented as the stimulated tree which differs in branching rate that described allocation of material necessary for the growth of each branch. There was a tendency of allocation ratio of nutrients, i.e. subbranch to main branch to decrease by the passage of year. Under assumption that branch was branched when accumulated material reached 1, it was possible to represent the allocation of nutrients are residual $nutrient{\times}\frac{1}{1+F};in main; branch, ; residual; nutrient{\times}\frac{F}{1+F}$ in subbranch, A(iA, iC)+$F^(iA-1)$ in current twig. Like this, the basic minute difference of the allocation of nutrients according to the branch resulted in complicated patterns in the tree crown.

• The Korean Journal of Ecology
• /
• 제16권4호
• /
• pp.417-428
• /
• 1993

백목련의 가지 생장유형은 두 가지의 생장전략에 의해 이루어지는 것으로 보인가. 하나는 환경 극복 전략이고 다른 하나는 생명 유지 전략으로 구분할 수 있는데, 이러한 전략은 한 그루의 나무 안에서도 같이 일어나고 있었다. 가지의 생장율은 조도에 밀접한 관련이 있었고(P<0.001) 물리적인 접촉의 유무와도 상당히 관련(P<0.01)되어 있는 반면에 방위별로는 우의차가 없었다. 상대 조도 1%미만의 경우는 주변 가지들과 거의 물리적인 접촉으로 대부분 생장이 제한되어 있었고, 10% 초과의 경우는 접촉에 의해 생장 제한이 거의 일어나지 않았다. 가지간의 물리적인 접촉의 유무는 분지율에 영향을 미치고 있었으나(P<0.05), 분지율은 조도에 무관하고, 방위별로도 유의차가 없었다. 생장 초기에는 주가지에서 부가지로의 물질 분배비가 크게 나타났으나 나무가 자라면서 환겨의 제한을 받게 됨에 따라 분배비는 다양하고 때로는 아주 적은 값을 보이기도 하였다. 이러한 다양한 생장율, 즉 물질의분배비의 다양(0.16~0.98)은 생장과 더불어 빚어지는 제약을 극복하여 태양 에너지를 최대한 효율적으로 흡수하기 위한 가지의 배치로 해석되며, 주어진 환경하에서 백목련이 택하는 최적의 생장 전략인 것으로 생각되다.

• 한국컴퓨터그래픽스학회논문지
• /
• 제23권5호
• /
• pp.29-38
• /
• 2017

본 논문은 나뭇가지 패턴을 의자의 골격에 임의로 합성하는(Tree-Inspired Chair) 모델링 기법을 제안한다. 여러 개의 입력모델을 합성하는 기존 기법과 다르게, 제안 기법은 하나의 메쉬만 사용하여, 사용자가 원하는 부분의 contour mesh로부터 나무 성장 시뮬레이션으로 생성된 패턴을 갖는 의자 모델링이 가능하다. 우리는 나뭇가지 패턴을 생성시킬 영역 contour mesh를 효율적으로 추출하기 위하여 새로운 기법을 제안한다. 우선, 입력된 모델의 face 면적에 기반한 contour mesh를 생성하고, 그 메쉬의 앞뒷면 정보를 이용하여 연결정보가 복원된 skeleton mesh를 생성한다. 또한, 입력 모델의 형상과 유사하게 나뭇가지 패턴을 생성하기 위해 형상 표면의 tangent vector를 고려하는 3-way 나무성장 시뮬레이션 기법을 제안한다. 제안기법은 기존의 가구 모델을 이용하여 간단한 파라미터의 조작만으로 나뭇가지 형상과 가구 모델의 골격을 결합하는 새로운 형태의 가구 모델링을 보여준다. 우리는 실험을 통하여 제안 기법의 성능과 유효성을 보여주었다.

• 지역연구
• /
• 제6권2호
• /
• pp.123-147
• /
• 1990

This paper examines the changing geography of producer service industries in the 1980s. The foci of this study are to analyze the regional distribution of each producer services, and to reveal the spatial linkage of producer services. Further this paper asserts the potential role of producer services for reducing the potential endogenous development in the periphery. During the 1981-86 period, producer service industries grew more rapidly than other service sectors and manufacturing sector. The main reason of the raid growth of producer services is attributable to an increase in demand for intermediate services from manufacturing firms. In order to compete an increasingly complex business environment, firms have expanded the amount of effort devoted to activities such as planning, coordination and control, and consequently have increased their use of producer services. The most distinctive feature of the location of producer services is spatial concentration into Seoul and surrounding region. Especially the degree of the concentration o business services into the Capital Region has been accelerating during the 1990s. The pattern of employment growth and regional distribution of producer services show a clear core / periphery disparity. Much of the regional inequality in producer services is largely due to variation in demand associated with the pattern of corporation headquarters with the pattern of corporation headquarters and branch plants location with large manufacturing firms. The analysis of spatial division of labor reflects that producer services are related to the location of headquarters in manufacturing industry. Headquarters in manufacturing firms and business service firms tend to cluster each other. Most of the headquarters spatially separated from branch offices are clustered heavily in Seoul. Especially headquarters of business services and insurance services are overwhelmingly concentrated into Seoul. The firms whose headquarters are located in Seoul have a linkage pattern on a nationwide scale. It is viewed have little potential for generating local multiplier effects and regional development. In the light of the result of this study, producer services are not likely to disperse soon to peripheral regions. Consequently the absence of policies directed at enhancing producer sevice in the periphery, concentration tendency would continue to reinforce the core's dominance at the expense of peripheral regions. From a regional perspective, the quality of a region's producer service sector is a key determinant of economic growth, since manu industrial location decisions are influenced by the differential availability of producer services among regions. Poor performance of producer services in peripheral regions seemed to be linked to the region's manufacturing base. Low-wage, standardized branch plants are not likely to induce the growth in knowledge intensive services associated with high-technology corporate headquarters. Producer services may help to create and attract new business including manufacturing firms, and also to enhance the productivity and competitiveness of local firms. Therefore the provision of service producing activities would be lead not only to generate and retain endogenous development but also to attract external firms, especially small and medium sized firms which have a lower propensity of internalized services. Hence, it may be more efficient to create and expanse new locally owned producer services rather than to attract branch plants of mult-locational firms in order to make indigenous economic development.

• 대한기계학회논문집A
• /
• 제20권4호
• /
• pp.2752-2759
• /
• 1996

This paper presents crack growth analysis approach on the basis of neural networks, a branch of cognitive science to high temperature low cycle fatigue that shows strong nonlinearity in material behavior. As the number of data patterns on crack growth increase, pattern classification occurs well and two point representation scheme with gradient of crack growth curve simulates crack growth rate better than one point representation scheme. Optimal number of learning data exists and excessive number of learning data increases estimated mean error with remarkable learning time J-da/dt relation predicted by neural networks shows that test condition with unlearned data is simulated well within estimated mean error(5%).

• Journal of Biosystems Engineering
• /
• 제21권3호
• /
• pp.315-324
• /
• 1996

This study was one of a series of studies on application of machine vision and image processing to extract the geometrical features of plants and to analyze plant growth. Several algorithms were developed to measure morphological properties of plants and describing the growth development of in-situ lettuce(Lactuca sativa L.). Canopy, centroid, leaf density and fractal dimension of plant were measured from a top viewed binary image. It was capable of identifying plants by a thinning top viewed image. Overlapping the thinning side viewed image with a side viewed binary image of plant was very effective to auto-detect meaningful nodes associated with canopy components such as stem, branch, petiole and leaf. And, plant height, stem diameter, number and angle of branches, and internode length and so on were analyzed by using meaningful nodes extracted from overlapped side viewed images. Canopy, leaf density and fractal dimension showed high relation with fresh weight or growth pattern of in-situ lettuces. It was concluded that machine vision system and image processing techniques are very useful in extracting geometrical features and monitoring plant growth, although interactive methods, for some applications, were required.

• Fisheries and Aquatic Sciences
• /
• 제5권2호
• /
• pp.108-113
• /
• 2002

Apical and subapical fragments of Gracilaria verrucosa (Hudson) Papenfuss (Rhodophyta) were cultured on a temperature-light gradient table with four temperature $(15,\;20,\;25\;and\;30^{\circ}C)$ and five light intensity $(20,\;40,\;60,\;80\; and\;100{\mu}mol\;photons\;m^{-2}s^{-l})$ regimes to examine growth responses. Their growth was measured weekly. Plant weight and lateral branch formation were affected by temperature and light intensity. As compared with other reports, relative growth rate (RGR) in both fragments was more or less high with 6.27 to $11.95\%$ $day^{-1}$. It was lowest at $15^{\circ}C$ with $20\mu mol$ photons $m^{-2}s^{-l}$, whereas, the highest value was recorded at $25^{\circ}C$ with $100\mu mol$ photons $m^{-2}s^{-l}$ During the experimental period, the growth pattern in G. verrucosa was significantly different between apical and subapical fragments, even though RGR based on weight was similar. Growth in apical fragments depended on elongation by apical growth. By contrast, subapical fragments mainly increased their weights by proliferation of lateral branch. This suggests that intercalary activity (e.g. lateral branch formation) is also an important means for growth of the thallus in Korean G. verrucosa. In conclusion, the relatively high growth potential with the intercalary activity in G. verrucosa will be helpful for mariculture in Korea.

• Fisheries and Aquatic Sciences
• /
• 제24권12호
• /
• pp.415-427
• /
• 2021

Wetland ecosystems act as natural freshwater purification systems, but their rich biodiversity is being threatened with the introduction of the non-native freshwater snail, Pomacea canaliculata. This study was conducted to measure the herbivory effects and growth rate of P. canaliculata on common macrophytes: Ipomoea aquatica, Ipomoea batatas, Pandanus amaryllifolius and Cucurma longa. In separate experiments, the macrophyte species were served as the snails' food as individual species and simultaneously. In the individual treatment, the growth pattern and rate were based on the snails' weight (mg/snail/day; n = 9) while the individual feeding consumption (mg/snail/day) was calculated from the leftover food. In the simultaneous treatment, the herbivory effects were evaluated as the feeding preference (%) from observations every two hours, while the total feeding consumption (mg) was calculated based on the food remaining after a 12-hour experiment (3 replicates: total n = 27). The results indicated that the growth pattern was significant for snails grazing on I. aquatica but not when other macrophyte species were eaten. The individual feeding consumption was higher when using I. aquatica than P. amaryllifolius but the growth rate for snails grazing on I. aquatica and P. amaryllifolius did not differ significantly. Meanwhile, the consumption of C. longa deterred the snails' growth rate. Although the snails consumed all the macrophytes in the individual experiment, when given the species simultaneously, the feeding preference and total feeding consumption were directed significantly more toward I. aquatica than P. amaryfollius and C. longa. We conclude that P. canaliculata is a generalist feeder given a limited choice of food but tends to show a strong feeding preference after being introduced to more food choices. These findings indicate that the introduction of P. canaliculata into wetland ecosystems may increase the herbivory effects on macrophytes, making these ecosystems vulnerable to the impact of eutrophication and biodiversity reduction.

• 아시안잔디학회지
• /
• 제1권1호
• /
• pp.42-48
• /
• 1987

This study was carried out to elucidate the physiological and ecological mechamism of the branch pattern and electronmicroscopic structure of photosynthetic organs in Zoysia japonica Steud. The angles between the internodes of rhizome and the branches of Z.iaponica were changed from 0 to 52 degrees. The rhizomes tended to branch from the 3th node to the 10th node. When the terminal bud was damaged by various environmental factors, the initial branching formation was appeared immediately to the 4th node. The internode growth of the rhizome started from the beginning of April and continued to the end of Octobor. It became evident that there is a division labor between two different kinds of photosynthetic cells of mesophyll and bundle sheath tissues in Z.japonica The thick-walled bundle sheath cells surrounds the leaf vascular bundles as the Kranz type and separates them from the mesophyll cells.

• 한국결정성장학회지
• /
• 제27권5호
• /
• pp.256-262
• /
• 2017

$1000^{\circ}C$ 이상의 고온에서도 안정적인 발색 특성을 보이는 세라믹 잉크를 활용한 디지털 프린팅 기술은 우수한 내구성을 가지는 제품을 다양한 디자인을 적용하여 생산할 수 있는 친환경 공정이라는 장점으로 인해 최근 관심이 높아지고 있다. 특히 건축용 세라믹 타일 산업에서 잉크젯 프린팅 기술 도입을 통한 디지털 공정으로의 전환은 점점 가속화되고 있으며, 이와 관련된 프린팅 시스템 및 고온발색 세라믹 잉크에 관한 연구가 활발히 진행되고 있다. 본 연구에서는 세라믹 타일의 표면 유약층에서 고온발색 세라믹 잉크의 인쇄적성을 분석하였다. 디지털 4원색인 Cyan, Magenta, Yellow, Black 색상의 고온발색 세라믹 잉크가 프린팅된 세라믹 타일의 표면 및 단면의 미세구조를 분석함으로써 세라믹 잉크의 종류에 따른 인쇄특성에 대해 비교하였다. 또한 고온 열처리 공정이 필수적으로 요구되는 세라믹 소재의 특성상 잉크젯 프린팅 후 세라믹 잉크 패턴의 열처리 공정에 따른 거동변화에 관하여 고찰하였으며, 세라믹 타일 유약층에서 세라믹 잉크의 인쇄적성은 미세구조 및 고온 소성 과정에 큰 영향을 받고 있음을 확인하였다.