• Title/Summary/Keyword: Seed shape

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Optical process of polysilicaon on insulator and its electrical characteristics (절연체위의 다결정실리콘 재결정화 공정최적화와 그 전기적 특성 연구)

  • 윤석범;오환술
    • Electrical & Electronic Materials
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    • v.7 no.4
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    • pp.331-340
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    • 1994
  • Polysilicon on insulator has been recrystallized by zone melting recrystallization method with graphite strip heaters. Experiments are performed with non-seed SOI structures. When the capping layer thickness of Si$\_$3/N$\_$4//SiO$\_$2/ is 2.0.mu.m, grain boundaries are about 120.mu.m spacing and protrusions reduced. After the seed SOI films are annealed at 1100.deg. C in NH$\_$3/ ambient for 3 hours, the recrystallized silicon surface has convex shape. After ZMR process, the tensile stress is 2.49*10$\^$9/dyn/cm$\^$2/ and 3.74*10$\^$9/dyn/cm$\^$2/ in the seed edge and seed center regions. The phenomenon of convex shape and tensile stress difference are completely eliminated by using the PSG/SiO$\_$2/ capping layer. The characterization of SOI films are showed that the SOI films are improved in wetting properties. N channel SOI MOSFET has been fabricated to investigate the electrical characteristics of the recrystallized SOI films. In the 0.7.mu.m thickness SOI MOSFET, kink effects due to the floating substrate occur and the electron mobility was calculated from the measured g$\_$m/ characteristics, which is about 589cm$\^$2//V.s. The recrystallized SOI films are shown to be a good single crystal silicon.

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Shape Control of Gold Nanocrystal: Synthesis of Faceted Gold Nanoparticles and Construction of Morphology Diagram

  • Ahn, Hyo-Yong;Lee, Hye-Eun;Nam, Ki Tae
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.281.1-281.1
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    • 2013
  • Shape control of gold nanocrystal is still one of the most important challenges remaining to achieve geometry dependent properties. Thus far, several strategies have been developed to control the shape of nanoparticles, such as adding capping agents and diverse additives or adjusting the temperature and pH. Here, we used an already established seed-mediated method that allowed us to focus on controlling the growth stage. Cetyltrimethylammonium bromide (CTAB) and ascorbic acid (AA) were used as the ligand and the reducing agent, respectively, without using any additional additives during the growth stage. We investigated how the relative ratio of CTAB and AA concentrations could be a major determinant of nanoparticle shape over a wide concentration range of CTAB and AA. As a result, a morphology diagram was constructed experimentally that covered the growth conditions of rods, cuboctahedra, cubes, and rhombic dodecahedra. The trends in the morphology diagram emphasize the importance of the interplay between CTAB and AA. Furthermore, high-index faceted gold nanocrystal was obtained by two step seeded growth. Already synthesized cubic particles developed into hexoctahedral nanocrystal consisting of 48 identical {321} facets, which indicates that the growth of gold nanocrystal is affected by initial morphology of seed particles. The hexoctahedral gold nanoparticles can be used in catalysis and optical applications which exploiting their unique geometry. Our research can provide useful guidelines for designing various facetted geometries.

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Hybrid CNN-SVM Based Seed Purity Identification and Classification System

  • Suganthi, M;Sathiaseelan, J.G.R.
    • International Journal of Computer Science & Network Security
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    • v.22 no.10
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    • pp.271-281
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    • 2022
  • Manual seed classification challenges can be overcome using a reliable and autonomous seed purity identification and classification technique. It is a highly practical and commercially important requirement of the agricultural industry. Researchers can create a new data mining method with improved accuracy using current machine learning and artificial intelligence approaches. Seed classification can help with quality making, seed quality controller, and impurity identification. Seeds have traditionally been classified based on characteristics such as colour, shape, and texture. Generally, this is done by experts by visually examining each model, which is a very time-consuming and tedious task. This approach is simple to automate, making seed sorting far more efficient than manually inspecting them. Computer vision technologies based on machine learning (ML), symmetry, and, more specifically, convolutional neural networks (CNNs) have been widely used in related fields, resulting in greater labour efficiency in many cases. To sort a sample of 3000 seeds, KNN, SVM, CNN and CNN-SVM hybrid classification algorithms were used. A model that uses advanced deep learning techniques to categorise some well-known seeds is included in the proposed hybrid system. In most cases, the CNN-SVM model outperformed the comparable SVM and CNN models, demonstrating the effectiveness of utilising CNN-SVM to evaluate data. The findings of this research revealed that CNN-SVM could be used to analyse data with promising results. Future study should look into more seed kinds to expand the use of CNN-SVMs in data processing.

Taxonomic studies of tribe Epilobieae Endl. (Onagraceae) in Korea based on morphology and seed microstructure (외부형태와 종자의 미세구조에 의한 한국산 바늘꽃족(바늘꽃과)의 분류학적 연구)

  • Lee, Sangryong;Heo, Kyeong-In;Lee, Sangtae;Yoo, Manhee;Kim, Yongseong;Lee, Joon Seon;Kim, Seung-Chul
    • Korean Journal of Plant Taxonomy
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    • v.43 no.3
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    • pp.208-222
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    • 2013
  • In this paper, we conducted the taxonomic study of the tribe Epilobieae Endl. and concluded that a total of nine taxa, including one Chamerion (Raf.) Raf. ex Holub and eight Epilobium L., exist in Korea. Although C. angustifolium subsp. angustifolium has been placed traditionally either in Epilobium or Chamaenerion, it can be clearly distinguished from the species of Epilobium by having alternate leaves, slightly zygomorphic flowers, non-clefted petals, and equal length of 8 stamens, supporting the recognition of genus Chamerion. All but one species of Epilobium, E. platystigmatosum, was investigated for the surface of seeds using scanning electron microscope (SEM). The seed sculpture of Korean Epilobium can be classified into three types, i.e., papillose, reticulate, and ridged. E. ciliatum subsp. ciliatum is the only species Epilobium, which has the ridged seed sculpture. E. amurense subsp. cephalostigma can be distinguished from conspecific E. amurense subsp. amurense based on leaf shape, trichome shape and distribution, size and habit. Both E. fastigiatoramosum and E. palustre have entire leaf margins, but they can be distinguished based on leaf shape, stigma, and seed sculpture; the former has elongated elliptic leaves, capitate stigma, ridged seed sculpture, whereas the latter one has elongated lanceolate leaves, club-shaped stigma, and reticulate seed sculpture. Finally, we report the first record of E. platystigmatosum in Korea, and further comparative study including conspecific populations from Japan and China can clarify the occurrence of this taxon in Korea.

Crown Shape Control of Pinus koraiensis S et. Z. (III) - Crown Shape Types for Seed and Timber Production from the Trees under Age Class III - (잣나무의 수형(樹型) 조절(調節) (III) - III영급(齡級) 이하(以下) 인공림(人工林)에서 잣과 목재(木材) 생산(生産)을 위한 수형(樹型) -)

  • Yi, Jae-Seon;Song, Jeong-Ho;Park, Moon-Han;Han, Sang-Urk
    • Journal of Korean Society of Forest Science
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    • v.88 no.2
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    • pp.195-204
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    • 1999
  • To improve nut production and timber quality in a plantation, crown shape controls were suggested for Korean white pines (Pinus koraiensis) under age class III through the analyses of the crown shape controls for seed orchard trees in several species, of crown status of controlled and uncontrolled trees in a Korean white pine seed orchard, and of growth characteristics of plantation trees under age class III. For nut production from the small trees less than 8 m, modified leader type can be applied by cutting the central leader and all branches below 1 m and keeping 4~5 nodes with 3~4 whorled branches a node locating 1 m apart. Trees with a 4~8 m long trunk below the first living branch are shaped into trees for nut and timber production, which have a 4~8 m long knotless stem and a modified leader type crown with 4~5 nodes with 3~4 whorled branches a node at a distance of 1 m. Trees, showing the first living branch at or above 9 m from the surface, are pruned severely for timber production and result in a central leader type containing two fifths of the initial crown. It is advisable to remove the leader and the branches when collecting cones or after/during October to take advantage of easy labor and little resin while cutting. After stem cut, branches showing apical dominance are to be cut to control height when necessary. The removal of the uppermost node may be needed to control the crown shape several years after the initial stem-cut.

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Development of Seed Pelleting Technology for Rice and Cabbage (벼 및 배추종자 Pelleting을 물질채색 및 기술개발)

  • 민태기
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.6
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    • pp.678-684
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    • 1996
  • Seed pelleting have successfully been used in many crops for better crop estab-lishment and for mechanizing seeding process for small crop seeds in developed countries. In this experiment various pelleting materials and binders were tested to get basic information on the shape, hardness and germination of pelleted seesds of cabbage (cv. Seoul Beachoo) and rice (cv: Ilpoom). PLL-11, paper clay, lime and coal ash were good materials to make smooth shape of the pellets with pel gel and AG-11 as binders, and PLL-ll as material and pelgel and AG-11 as binders were the best among them in consideration of shape and hardness together. The hardness of the pelleted seeds were differed with each other depending on both of the pelleting materials and binders. Pelleted cabbage seeds coated by pelgel as binder with different materials showed lower germination percentge than control in general, but the seeds pelleted by PLL-11 with different binders showed no restraint effects. When the cabbage seed pelleted by PLL-11 with pelgel as binder showed almost same germination percentage as control. The pH and electrical conductivity of the extract from bentonite and zeolite were very higher than other materials tested and germination percentage showed a little lower than control when the cab-bage seed planted on the filter paper damped with the extract. As a result, PLL-11 as pelleting material and pel gel and AG-11 as binder appeared the good materials to make pellets of cabbage seeds and rice in consideration of shape, hardness and germination.

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A Study on Fabrication of Conductor Patterns on AlN Ceramic Surface by Laser Direct Writing (레이저 직접묘화법에 의한 AlN 기판상의 전도성 패턴 제작에 관한 연구)

  • Lee, Je-Hoon;Seo, Jung;Han, Yu-Hee
    • Laser Solutions
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    • v.3 no.2
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    • pp.25-33
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    • 2000
  • One of perspective direction of microfabrication is direct laser writing technology that allows to create metal, semiconductive and dielectric micropatterns on substrate surface. In this work, a two step method, the combination of seed forming process, in which metallic Al seed was selectively generated on AlN ceramic substrate by direct writing technique using a pulsed Nd : YAG laser and subsequent electroless Ni plating on the activated Al seed, was presented. The effects of laser parameters such as pulse energy, scanning speed and pulse frequency on shape of Alseed and conductor line after electroless Ni plating were investigated. The nature of the laser activated surface is analyzed from XPS data. The line width of this metallic Al and Ni is analyzed using SEM. As a results, Al seed line with 24㎛ width and 100㎛ isolated line space is obtained. Finally, laser direct writing can be applied in the field between thin and thick film technique in electronic industry.

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Anatomical and Morphological Features of Seeds in Portulaca

  • Kim, InSun
    • Applied Microscopy
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    • v.42 no.4
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    • pp.194-199
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    • 2012
  • The anatomy and morphology of seeds from 10 Hawaiian Portulaca taxa were examined to explore patterns of variation among the taxa, and to evaluate their phylogenetic relationships. Features of seeds were assessed employing microtechnique procedures, statistical analysis, and scanning electron microscopy (SEM). Anatomically, the orientation of embryo was consistent across taxa, and all seeds examined had central nutritive tissue and integuments comprising the peripheral embryo. Seeds were generally small, circular to ovoid in shape, and either smooth or rough-surfaced, with tubercules. Variation in seed size was noted, although minimal within small seeded group. The size of seeds ranged from 0.50~1.26 mm in length, and 0.55~1.34 mm in width, with similar weights. Seeds were distinguished by the sculpture and arrangement of the testa epidermis and the way in which their stellulate-tessellate cells uniquely fit together. Using a multiple range test (ANOVA), two groups were established by seed characteristics. The SEM also demonstrated morphological differences in testa sculpturing. The results obtained confirm the usefulness of seed characteristics in the identification of the species examined, and furthermore, allow for the separation of the Hawaiian Portulaca into two groups.

Sediment Preference and Burrow Shape of Spoon Worm, Urechis unicinctus (Von Drashe) in Laboratory Culture (실험실 사육에 의한 개불, Urechis unicinctus의 저질선택성과 굴의 형태)

  • 강경호
    • Journal of Aquaculture
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    • v.12 no.3
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    • pp.193-196
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    • 1999
  • In order to obtain the basic data for the effective seed production of Ureshis unicinctus sediment preference, burrow shape and burrowing depth in sediment were investigated in the laboratory. The highest valus in both sediment preference and burrowing rate of U. unicinctus were shown at fine and (0.11~0.50mm in the mean diameter). U. unicinctus made various types of burrows, such as J, L, S and U shapes. Generally only one individual inhabits in burrow with head-up.

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Characteristics of Spectral Matched Ground Motions Time Histories According to Seed Ground Motion Selection (원본 지반운동 시간이력에 따른 스펙트럼 부합 시간이력의 특성)

  • Choi, Da Seul;Ji, Hae Yeon;Kim, Jung Han
    • Journal of the Earthquake Engineering Society of Korea
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    • v.25 no.1
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    • pp.43-52
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    • 2021
  • According to several seismic design standards, a ground motion time history should be selected similar to the design response spectrum, or a ground motion time history should be modified by matching procedure to the design response spectrum through the time-domain method. For the response spectrum matching procedure, appropriate seed ground motions need to be selected to maintain recorded earthquake accelerogram characteristics. However, there are no specific criteria for selecting the seed ground motions for applying this methodology. In this study, the characteristics of ground motion time histories between seed motions and spectral matched motions were compared. Intensity measures used in the design were compared, and their change by spectral matching procedure was quantified. In addition, the seed ground motion sets were determined according to the response spectrum shape, and these sets analyzed the response of nonlinear and equivalent linear single degrees of freedom systems to present the seed motion selection conditions for spectral matching. As a result, several considerations for applying the time domain spectral matching method were presented.