• Title/Summary/Keyword: leaf structure

Search Result 379, Processing Time 0.027 seconds

Population Dynamics of Symplocarpus renifolius 1. Population Structure and Vegetative Growth (앉은부채 (Symplocarpus renifolius) 개체군의 동태 1.개체군의 구조와 영양생장)

  • Min, Byeong-Mee;Kang, Hyun-Jung
    • The Korean Journal of Ecology
    • /
    • v.17 no.4
    • /
    • pp.453-461
    • /
    • 1994
  • Size class structure and vegetative growth of a perennial herb of the temperate deciduous forests, Symplocarpus renifolius Schott, were studied from 1991 to 1994 in Namhansansung, Kyonggi Province, Korea. The size class structures of leaf number and leaf area per individual followed bell-shape curve, i.e. frequency of middle class was relatively high. The leaf area increased from the late-March to mid-May. At the end of the growing season, leaf area(length X breadth) was proportional to biomass, especially aboveground biomass. The leaf number and leaf area per individual increased at the rate of 0.08 leaf/year and 9.7 $cm^2/year$, respectively. The size of the individuals in large-sized classes, in leaf number and leaf area, decreased in next year, while the size of the individuals in small-sized classes increased. Therefore, it was concluded that the size class structure of S. renifolius population was largely determined by the growth form.

  • PDF

A Study on the Anisotropic Flow Characteristics of Droplets on Rice Leaf Surface (벼 잎 표면에서 액적의 이방성 흐름 특성에 관한 연구)

  • Kim, Tae Wan
    • Tribology and Lubricants
    • /
    • v.33 no.6
    • /
    • pp.251-255
    • /
    • 2017
  • In this study, we aimed to clarify the wettability and anisotropic flow characteristics of rice leaves as a basic study for engineering applications of anisotropic flow characteristics of rice leaf surface. To investigate the surface structure of rice leaf, the micro grooves and asperities of rice leaves were analyzed and quantified by scanning electron microscope, Confocal laser scanning microscopy, and stylus profilometer. The analysis of the structure of rice leaf surface confirmed that asymmetrical cone - like protrusions in leaf veins were inclined toward the leaf tip. The static contact angle test showed that the contact angle at the midline vein or leaf vein location where the micropapilla is concentrated is about $20^{\circ}$ higher than the leaf blade position. The contact angles of fresh and dried rice leave were also compared. The dried rice leaves showed a contact angle of about $5^{\circ}$ to $15^{\circ}$ higher than that of fresh leaves, suggesting that the volume of the protrusions decreased as the water was removed, thus reducing the contact area with the droplet. In the contact angle history test the hysteresis in the leaf tip direction was found to be much lower than that in the leaf petiole direction. This results can be explained that asymmetrical cone - like protrusions had a significant effect on the droplet flow characteristics through contact angle hysteresis experiment.

A Experimental Study on the Usefulness of Structure Hints in the Leaf Node Language Model-Based XML Document Retrieval (단말노드 언어모델 기반의 XML문서검색에서 구조 제한의 유용성에 관한 실험적 연구)

  • Jung, Young-Mi
    • Journal of the Korean Society for information Management
    • /
    • v.24 no.1 s.63
    • /
    • pp.209-226
    • /
    • 2007
  • XML documents format on the Web provides a mechanism to impose their content and logical structure information. Therefore, an XML processor provides access to their content and structure. The purpose of this study is to investigate the usefulness of structural hints in the leaf node language model-based XML document retrieval. In order to this purpose, this experiment tested the performances of the leaf node language model-based XML retrieval system to compare the queries for a topic containing only content-only constraints and both content constrains and structure constraints. A newly designed and implemented leaf node language model-based XML retrieval system was used. And we participated in the ad-hoc track of INEX 2005 and conducted an experiment using a large-scale XML test collection provided by INEX 2005.

Analysis of Productivity in Rice Plant II Evaluation of Canopy Structure and Canopy Score (벼의 생산력(生産力) 분석(分析) II 생산구조(生産構造) 평가(評價)와 군낙평점(群落評點))

  • Park, Hoon;Kim, Yung Sup;Yoon, Jong Hyuk
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.5 no.1
    • /
    • pp.9-15
    • /
    • 1972
  • Comparative analyses of canopy structure were conducted using newly bred high yield rice cultivars (IR 667-Suwon 213 and 214) and commercial varieties (Jinhung and Paldal) under the field condition. "Canopy score" as criteria of canopy structure was proposed. The results were summerized as follows: 1. IR667 line (IR8${\times}$Taichung Native 1${\times}$Yukara) showed lower canopy height, greater tiller openness, smaller leaf openness and leaf length ratio (flag leaf/3rd), shorter 4th and 5th internode length, greater diameter of 5th internode, consequently greater leaf area index, panicle weight and leaf weight ratio (leaf/leaf sheathculm) as merits, and greater leaf width, smaller leaf number(number of leaf/$m^2$)and specific leaf area($cm^2/g$) and faster destruction of canopy by senescence as demerits comparing with commercial varieties. 2. IR 667 line showed much higher "Canopy score", subsequently higher yield. 3. The quality of individual leaf was better in the commercial varieties indicating that the best combination for the better yield would be the leaf of commercial varieties with the structure of IR667 line.

  • PDF

Relation Between the Growth Habitat and the Leaf Quality of Cultivated Mulberry Plants (뽕나무의 생육특성과 엽질과의 관계)

  • 김준호
    • Journal of Plant Biology
    • /
    • v.17 no.3
    • /
    • pp.118-126
    • /
    • 1974
  • Mulberry plants cultivated in mid-Korea were studied on the growth habitat, canopy type, productive structure and vertical light intensity in relation to the quality of mulberry leaves for sericulture. The growth in length of new branch of summer cut mulberry in spring was vigorous on the uppermost of old shoot. Numbers of leaves on a branch were barely 4 leaves on lower than 20th branch from base, but those were 13 leaves on higher than 24th branch. Area of leaves completely expanded was broad on high branch, but narrow on low one. The form of canopy, the type of productive structure and the vertical light distribution depend upon varieties of cultivated mulberry plants were classified according to characteristic of each variety in two groups, respectively; globular and columnar form in canopy, broad leaves and narrow leaves types in productive structure, and seriously obstructured the light and fairly transmitted the light into lower leaf stratum invertical light distribution. Out of varieties of mulberry investigated, Suwon No. 4 and Rosang were belong to the former characters, but Illchiroe and Kaeryangsubun were to the latters. The values of leaf dry matter index and dry matter production produced by leaves were increased in direct proportion to the height of leaf stratum; the leaf dry matter index of the uppermost leaf was twice as much that of the lowest, and the dry matter production by the highest leaf was 17 times compared with that by the lowest leaf. It is assumed that the meagre leaves occurred in the lower leaf stratum of Suwon No. 4 and Rosang were caused to diminished the dry matter index and dry matter production in the under leaves of plant, which were affected by receiving the weak light.

  • PDF

Theories and Measurement Techniques for LAI of Crops (밭작물의 엽면적지수(LAI)에 대한 이론 및 측정기술)

  • Park, Jong-Hwa;Lee, Sang-Hyuk;Shin, Yong-Hee;Park, Min-Seo
    • Proceedings of the Korean Society of Agricultural Engineers Conference
    • /
    • 2002.10a
    • /
    • pp.21-24
    • /
    • 2002
  • Many methods are available to measure leaf area index(LAI) directly and are variations of either Leaf area index(LAI) and leaf angle distribution are widely used indices of canopy structure that are difficult to measure directly. Direct measurements of canopy structure are tedious and labor intensive in small canopies and nearly impossible in large forest canopies. This study introduced fundamental theories in LAI measurements and applied that for several crops.

  • PDF

Study on the Characteristics and Production Techniques of the Clay Seated Vairocana Buddha Triad of Seonunsa Temple, Gochang(2) - Analysis of Gold Leaf Layers and Internal Structure of the Clay Buddha Statues

  • Lee, Hwa Soo;Kim, Seol Hui;Kim, Won Woo;Yu, Yeong Gyeong;Han, Kyeong Soon
    • Journal of Conservation Science
    • /
    • v.37 no.1
    • /
    • pp.43-54
    • /
    • 2021
  • In this study, a scientific analysis of the gold leaf layers and internal structure of the Clay Seated Vairocana Buddha Triad in Seonunsa Temple, Gochang (Treasure No. 1752) was conducted. The surface of the Buddha statues is a gold foil, and the gold leaf layer consists of four layers. The gold leaf layer first composed on the molding clay was produced in the order of lacquer-fabrics-lacquer-gold foil. Subsequently, it was confirmed that the work was performed three times in the same way. The composition of the Buddha statues was divided into the head, body or upper body, lower body, and pedestal. The body was made in a cylindrical form by connecting vertically oriented wooden materials, and the head and lower body were also connected to the body in an empty form. Thus, the head, body, and lower body are grafted structures that are connected to a single Bokjang-gong. It was confirmed that the Clay Seated Vairocana Buddha Triad in Seonunsa Temple was made using wood materials for the basic form, after which the detailed form was created with molding clay, and the surface was finished with a process of layering gold foil and substances presumed to be lacquer.

The Impact of the Morphological Characteristics of Leaves on Particulate Matter Removal Efficiency of Plants

  • Son, Deokjoo;Kim, Kwang Jin;Jeong, Na Ra;Yun, Hyung Gewon;Han, Seung Won;Kim, Jeongho;Do, Gyung-Ran;Lee, Seon Hwa;Shagol, Charlotte C.
    • Journal of People, Plants, and Environment
    • /
    • v.22 no.6
    • /
    • pp.551-561
    • /
    • 2019
  • This study was conducted to find out differences in the removal efficiency of particulate matter (PM) depending on the type of plants and the morphological characteristics of leaves. A total of 12 plants were used, with three plants selected for each type of leaves (big leaf, small leaf, compound leaf, needle leaf). We measured the removed amount of PM10 and PM2.5, the structure of the abaxial leaf surface, and the weight of the wax layer of each plant. Plants with the high removal efficiency of PM included Pachira aquatica Aubl., Ardisia crenata, and Dieffenbachia 'Marianne', and plants with the low removal efficiency included Nandina domestica Thunb, Schefflera arboricola, and Quercus dentata. The abaxial leaf surface having a high removal efficiency of PM had many large wrinkles, and the abaxial leaf surface having a medium removal efficiency was flat and smooth. On the other hand, there were many fine hairs on the abaxial leaf surface with a low removal efficiency. According to the plant leaf type, the PM10 removal efficiency of plants with needle leaves was about three times higher than that of other plants. In particular, the wax layer of conifers weighed 6-24 times higher than those of other plants. The stomata of conifers were evenly distributed on the adaxial and abaxial leaf surfaces; however, the stomata of Sciadopitys verticillata appeared in the form of papillae unlike general stomata. Therefore, the removal efficiency of PM varied depending on the macro-, and micro-morphological characteristics of plant leaves such as the structure of the abaxial leaf surface, and the weight of the wax layer. Based on this research, selecting plants that are effective in reducing PM in consideration of the plant type and leaf characteristics will improve indoor air quality and decrease exposure of PM to human body.

Experimental and numerical analysis of RC structure with two leaf cavity wall subjected to shake table

  • Onat, Onur;Lourenco, Paulo B.;Kocak, Ali
    • Structural Engineering and Mechanics
    • /
    • v.55 no.5
    • /
    • pp.1037-1053
    • /
    • 2015
  • This paper presents finite element (FE) based pushover analysis of a reinforced concrete structure with a two-leaf cavity wall (TLCW) to estimate the performance level of this structure. In addition to this, an unreinforced masonry (URM) model was selected for comparison. Simulations and analyses of these structures were performed using the DIANA FE program. The mentioned structures were selected as two storeys and two bays. The dimensions of the structures were scaled 1:1.5 according to the Cauchy Froude similitude law. A shake table experiment was implemented on the reinforced concrete structure with the two-leaf cavity wall (TLCW) at the National Civil Engineering Laboratory (LNEC) in Lisbon, Portugal. The model that simulates URM was not experimentally studied. This structure was modelled in the same manner as the TLCW. The purpose of this virtual model is to compare the respective performances. Two nonlinear analyses were performed and compared with the experimental test results. These analyses were carried out in two phases. The research addresses first the analysis of a structure with only reinforced concrete elements, and secondly the analysis of the same structure with reinforced concrete elements and infill walls. Both researches consider static loading and pushover analysis. The experimental pushover curve was plotted by the envelope of the experimental curve obtained on the basis of the shake table records. Crack patterns, failure modes and performance curves were plotted for both models. Finally, results were evaluated on the basis of the current regulation ASCE/SEI 41-06.

Evo-Devo of Leaf Shape Control with a Special Emphasis on Unifacial Leaves in Monocots

  • Yamaguchi, Takahiro;Tsukaya, Hirokazu
    • Korean Journal of Plant Taxonomy
    • /
    • v.37 no.4
    • /
    • pp.351-361
    • /
    • 2007
  • In angiosperms, leaves typically develop as three-dimensional structure with dorsoventral, longitudinal, and lateral axes. We have shown that the control of two axes of leaves, longitudinal and lateral axis, can be genetically separable, and four classes of genes are responsible for the polar cell expansion and polar cell proliferation in Arabidopsis. In monocots, unifacial leaf, in which leaf surface consists only of abaxial identity, has been evolved in a number of divergent species. The unifacial leaves provide very unique opportunities for the developmental studies of the leaf axes formation in monocots, because their leaf polarities are highly disorganized. In addition, the mechanism of the parallel evolution of such drastic changes in leaf polarities is of interest from an evolutionary viewpoint. In this article, we describe our recent approaches to reveal the mechanism of unifacial leaf development and evolution, including recent advances in the leaf polarity specification in angiosperms.