• Korean Journal of Materials Research
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• v.2 no.1
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• pp.52-57
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• 1992

The macro defects of $LiNbO_3$ crystals grown by the Czochralski method were strongly influenced by the single crystal growth parameters such as growth rate, thermal gradient and crystal rotation rate. The optimum growth conditions of a $LiNbO_3$ single crystal with 1" in diameter were $70~100^{circ}C/cm$ temperature gradient, 5~10 mm/hr growth rate and 40 rpm crystal rotation rate. In these conditions, we could grow crystals which had no cellular structure with easy diameter control, and any crack was not formed after the crystal was cooled.oled.

• Journal of Biosystems Engineering
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• v.43 no.1
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• pp.30-36
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• 2018

Purpose: The objective of this study is to evaluate the effect of cultivation conditions on the growth and glucosinolate content of Chinese cabbage and kale. Methods: Chinese cabbage and kale were grown in three different cultivation conditions, including a plant factory, greenhouse, and open field. Samples were collected at two harvesting times (10 d and 20 d after transplanting the seedlings). Nine growth parameters (plant height, plant width, number of leaves, petiole diameter, SPAD readout, leaf length, leaf width, stem diameter, and plant weight) were measured immediately after harvesting, and the samples were freeze-dried and stored until the glucosinolate content was analyzed. Mean values of the growth parameters and glucosinolate contents were evaluated using Duncan's multiple range tests. Results: The results indicated that the plant parameters of the Chinese cabbage and kale were greater for plants grown in the plant factory and greenhouse. The plant height, width, and weight showed significant differences in the Duncan's multiple range tests at a 5% level. The plant factory also produced greater contents of most of the glucosinolates. Conclusions: Three different cultivation conditions significantly affected the growth and glucosinolate contents of Chinese cabbage and kale. Further study is necessary to investigate other functional components and different vegetable varieties.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.207-218
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• 1998

A site survey in two apartment complexes and a nursery experiment were carried out in this study to provide basic data of the long-pending growth characteristics of major landscaping trees, such as Picea abies, Pinus parviflora, Metasequoia glyptostroboides, Magnolia denudata, Acer buergerianum and Acer palmatum. According to the main results, the survival rates were very low, reflected by the average survival rate of the four species was 95% at the nursery site. And, it was presumed that the site conditions of two apartment complexes for tree growth were very inferior to those of the nursery site, taking into consideration that the increment percents of growth factors of the tree species at the nursery site were relatively higher than those of the apartment complexes. The distribution patterns of the current growth factors of trees showed a normal distribution. The regression equation of breast diameter on diameter at root collar showed especially high predictability. And, it was thought that the most critical limiting environmental factors on tree growth at the apartment complexes were found to be alkaline pH caused by excessive Ca, high percent base saturation, insufficiency of available moisture content, bad drainage due to inferior soil texture, high soil hardness, lack of organic matter and shortage of cation exchange capacity in soil.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.5
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• pp.11-19
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• 2003

The main purpose of this study was to examine the application of the root system as a shore protection material through the measurement of the 개ot growth curve of Salix gracilisyla Miq. depending on the cutting size. As materials and methodology, nine group of cuttings were classified by the length(l0cm, 20cm, 40cm) and the diameter(0.72cmm$\pm$0,02, 0.58cm$\pm$0.02, 0.35cm$\pm$0.02), Each group was stuck to a flooding bed of sandy loam(Sand 60,36%, Silt 28%, Clay 11.64%) on 27th March 2001, After 65 growing days, the weight and length of the newly developed roots, shoots, and leaves were measured and analysed, This was repeated at 99, 129, 159, and 190 growing days. The major findings were as follows. The primary determinant of the root growth rate was on the weight of cutting, The secondary determinant was on the number of growing days. In addition, the dominant dimension of the cutting was the diameter rather than the length, The thicker cutting caused more rapid and stable growth however the longer cutting made the growth of the root slower and more unstable.

• Korean Journal of Organic Agriculture
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• v.6 no.1
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• pp.109-116
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• 1997

This experiment was carried out to examine the effect of various functional materials such as bioceramic podwers, crushed shells and elvanites supplemented to the each substrate on the seedlings growth of cucumber, watermelon and tomato. The seedlings were grown in pots filled with substrates of bioceramic podwers, crushed shell and elvanites. The growth of cucumber seedlings in terms of plant height, stem diameter, leaf width, leaf area, plant fresh and dry weight was promoted by adding the bioceramic. powder (1 to 2g/kg), crushed shells (20 to 80g/kg) or elvanites (20 to 80g/kg). Watermelon seedlings in terms of plant height, number of leaves and leaf area were greater than those of the control by adding bioceramics (1 to 2g/kg). Plant height was also promoted by the adding of bioceramic power from 16 days after treatment. But leaf area was increased from 8 days after treatment, while stem diameter was not affected. Watermelon seedlings were also influenced by adding curshed shells (20 to 80g/kg) and elvanites (20 to 40g/kg) into each substrate. The growth of characteristics of tomato seedlings were promoted by adding 1 to 3g/kg of bioceramics, 10 to 80g/kg of crushed shell or 20 to 40g/kg of elvanites, respectively. Especially, root growth was greatly influenced by bioceramic powder, whereas the shoot growth(leaves and stem) was stimulated by crushed shells and elvanites suppemented into substrate.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.210-210
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• 2000

Vertically well aligned multi-wall carbon nanotubes (CNT) were grown on nickel coated glass substrates by plasma enhanced hot filament chemical vapor deposition at low temperatures below 600$^{\circ}C$. Acetylene and ammonia gas were used as the carbon source and a catalyst. Effects of growth parameters such as pre-treatment of substrate, plasma intensity, filament current, imput gas flow rate, gas composition, substrate temperature and different substrates on the growth characteristics of CNT were systematically investigated. Figure 1 shows SEM image of CNT grown on Ni coated glass substrate. Diameter of nanotube was 30 to 100nm depending on the growth condition. The diameter of CNT decreased and density of CNT increased as NH3 etching time etching time increased. Plasma intensity was found to be the most critical parameter to determine the growth of CNT. CNT was not grown at the plasma intensity lower than 500V. Growth of CNT without filament current was observed. Raman spectroscopy showed the C-C tangential stretching mode at 1592 cm1 as well as D line at 1366 cm-1. From the microanalysis using HRTEM, nickel cap was observed on the top of the grown CNT and very thin carbon amorphous layer of 5nm was found on the nickel cap. Current-voltage characteristics using STM showed about 34nA of current at the applied voltage of 1 volt. Electron emission from the vertically well aligned CNT was obtained using phosphor anode with onset electric field of 1.5C/um.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.36-41
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• 1985

Heritability of height and diameter growth was estimated for 3-year-old seedlings from 75 mother trees in Pinus koraiensis. Estimates of single tree and family heritability by variance analysis were $h^2{_I}$ > 1.0 and $h^2{_F}=0.87$ for height and $h^2{_I}=0.52$ and $h^2{_F}=0.64$ for diameter respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.6
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• pp.535-541
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• 1999

Low-dislocation-density large-diameter GaAs single crystals with low-residual-strain have been strongly required. We have developed dislocation-free 3-inch Si doped GaAs crystals for photonic devices, and low-dislocation-density low-residual-strain 4-inch to 6-inch semi-insulating GaAs crystals for electronic devices by Vertical Bridgman(VB) technique. We confirmed that VB substrates with low-residual-strain have higher resistance against slip-line generation during MBE process. VB-GaAs single crystals show uniform radial profile of resistivity reflecting to the flat solid-liquid interface during the crystal growth. Uniformity of micro-resistivity of VB-GaAs substrate is much better than of the LEC-GaAs substrate, which is due to the low-dislocation-density of VB-GaAs single crystals.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.4
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• pp.137-139
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• 2008

Floating zone, neutron transmutation-doped and magnetic Czochralski silicon crystals are being widely used for fabrication power devices. To improve the quality of these devices and to decrease their production cost, it is necessary to use large-diameter wafers with high and uniform resistivity. Recent developments in the crystal growth technology of Czochralski silicon have enable to produce Czochralski silicon wafers with sufficient resistivity and with well-controlled, suitable concentration of oxygen. In addition, using Czoehralski silicon for substrate materials may offer economical benefits, First, Czoehralski silicon wafers might be cheaper than standard floating zone silicon wafers, Second, Czoehralski wafers are available up to diameter of 300 mm. Thus, very large area devices could be manufactured, which would entail significant saving in the costs, In this work, the conventional Czochralski silicon crystals were grown with higher oxygen concentrations using high pure polysilicon crystals. The silicon wafers were annealed by several steps in order to obtain saturated oxygen precipitation. In those wafers high resistivity over $5,000{\Omega}$ cm is kept even after thermal donor formation annealing.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.129-157
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• 1999

Low-dislocation-density large-diameter GaAs single crystals with low-residual-strain have been strongly required. We have developed dislocation-free 3-inch Si-doped GaAs crystals for photonic devices [1], and low-dislocation-density low-residual-strain 4-inch to 6-inch [2, 3] semi-insulating GaAs crystals for electronic devices by Vertical Boat (VB) technique. We confirmed that VB substrates with low-residual-strain have higher resistance against slip-line generation during MBE process. VB-GaAs single crystals show uniform radial profile of resistivity reflecting to the flat solid-liquid interface during the crystal growth. Uniformity of micro-resistivity of VB-GaAs substrate is much better than that of the LEC-GaAs substrate, which is due to the low-dislocation-density of VB-GaAs single crystals.