• Korean Journal of Medicinal Crop Science
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• v.24 no.1
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• pp.21-26
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• 2016

Background : Acer pictum is a deciduous tree belonging to the family Aceraceae. This study was conducted to collect basic data on mass propagation techniques by surveying the germination and growth characteristics of A. pictum seeds. Methods and Results : A. pictum seeds were harvested in 2014 on August 19, September 5, September 29 and October 31. The seeds were then sown on the same dates they were harvested. A portion of seeds harvested in August 2014 were stored at low temperatures and subsequently sown on March 11, 2015. The germination rate of A. pictum seeds was highest in seeds that were stored harvested on October 31. Mean germination time (MGT) was shortest and germination velocity (Rs) was fastest in seeds harvested on October 31. Root collar diameter, total root length, and dry weight were also highest from seeds collected October 31. Conclusions : A. pictum seeds harvested on October 31 had highest germination and growth rates compared with seeds harvested on earlier dates. It is expected that these results demonstrating optimum harvesting and sowing dates will be applicable to future seedling production for this tree species.

• The Korean Journal of Ecology
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• v.17 no.4
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• pp.523-531
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• 1994

Optimal conditions for the seed germination and growth of Hedyotis diffusa were studied. As photoperiod was increased from 12 hr to 24hr, the germination rate of Hedyotis diffusa was gradually increased. The photoperiod and temperature inflenced on the fermination synergistically. After the growth of 20 weeks under the natural condition (June~Oct.), the length of H. diffusa was $38.9{\pm}4.2cm$ (15.5~52.5cm), and total dry weight per $3.3m^2$ was $316.7{\pm}10.3g$. It is considered that H. diffusa could be cultivated in a part of inland. The anticancer effect of H. diffusa extract was examined. F-344 rats aged 6 weeks were divided into 3 groups and were given an I.P. of diethylnitrosamine at 200mg/kg body weight as a promoter, initially. And in two weeks after the beginnign of the experiment, group 1 was supplied iwth feed containing 0.02% 2-AAG as a promoter for 6 weeks. Group 2 was supplied with feed containing extracts of H.diffusa (0.02%) for two weeks. Group3 was supplied with only basal diet. All rats were sacrificed for partial hepatectomu, and the antipromoting effect was examined by the number 문 area per $cm^2$ of foci in river. In group 1, the number of hyperplastic nodule was $18.5{\pm}7.7$, but in group2, it was drastically reduced to $10.3{\pm}1.8$ rather thn those of group1. The total area of nodules $(mm^2)$ /whole liver $(cm^2)$ of group 1 and group2 were $19.2{\pm}7.7$ and $5.0{\pm}3.2$, respectively. These results indicate that extract of H.diffusa act as an anticancer agent at statistically significant level (p<0.001).

• Journal of Environmental Health Sciences
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• v.33 no.6
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• pp.488-492
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• 2007

The influence of additive materials including saw dust and cow manure in the ripening of leather sludge for the efficient vermisabilization was studied. The ripening characteristics of the leather sludge, the growth of earthworms in the growth bed and the by-products like cast were observed according to the mixing ratio of additive materials. When the mixed leather sludge of which the additive materials contents were over 20% were ripened for 50 days, the values of ORP and alkalinity were changed to the favorable ranges for earthworms, the positive (+) and below 1,000 mg/l as $CaCO_3$, respectively. The velocity of ripening improving the characteristics of the leather sludge was faster in the sludge mixed with cow manure than saw dust. This results could also be verified from the monitoring of the states of earthworm growth using the survival rate, the increase rate of lifeweight and the hatching rate of earthworm cocoon in the their growth bed packed with the ripened sludge. The values of CEC in cast, the vermi-stabilized sludge, were increased with the mixing ratio of additive materials, but the content of heavy metals was drcreased by the dilution effect and accumulation in the earthworm body. Above results show that the leather sludge might be efficiently stabilized by earthworms through the ripening for 50 days using additive materials. Cow manure can be used as a good additive materials for leather sludge as much as saw dust, and the optimum content of additive materials in the well-ripened leather sludge was about 30%.

• Journal of Families and Better Life
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• v.29 no.2
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• pp.13-22
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• 2011

Since environmental problems were globalized, discussions on 'Sustainable Development' started from Rio Declaration on Environment and Development(Rio Agenda 21). In Korea, the idea of 'Green Growth' was introduced and generalized since the celebration speech made on 8.15(Independence Day of South Korea) on 2008. And Low Carbon- Green Growth Basic Law was established on 2010. There are 3 strategies and 10 sub-tasks to achieve green country-traffic and green revolution of life. Family resource management is capable of changing life style from energy wasty to ecologically green. The value of family resource management plays a critical role in changing the lifestyle through influencing the goal and standard setting. So, this study is aimed to suggest the green value and green way of life from the perspective of family resource management. Results are as follow. First, the green value is to change from 'material-oriented' to 'people-oriented'. The 'material-oriented value pursues pleasure from possessing, but the 'people-oriented' value pursues pleasure from being itself. Second, the change from the value of 'human-mastery of the nature' to the value of 'mother -nature' is necessary. The value of 'human-mastery of the nature' seeks pleasure from the velocity and tangible outcome. But the value of 'mother- nature' seeks pleasure from the time to relax and slow way of life. 'Third, the change from the value of 'individualism' to the value of 'community sprit' is necessary. Individualism focuses on man's achievement, which may fall into family egoism. And the green way of life suggests the change from 'results-oriented' to 'enjoy the process itself", from 'consumption' to 'ecological restoration' and from 'work to home and then home to community'.

• Wind and Structures
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• v.36 no.3
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• pp.175-200
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• 2023

The large eddy simulation (LES) of the flow around a circular cylinder is not only affected by the sub-grid scale (SGS) model but also by the grid resolution of the computational domain. To study the influence of different grids on the LES results, the LES simulations of the flow around a circular cylinder with different grids at Reynolds number (Re) = 3900 was performed. A circular computational domain with different radial growth rates and circumferential and spanwise grid numbers was adopted for the simulations. Meanwhile, the aerodynamic forces, wind pressure coefficients, mean and instantaneous flow fields, and the effect of grid resolution on them were comprehensively analyzed. The results indicate that the lift coefficient, wind pressure coefficient, and recirculation length are significantly affected by the radial growth rate of the grid and the circumferential grid number. The spanwise grid number has a significant influence on the three-dimensionality of the flow and plays an important role in velocity fluctuations in the wake region. Nevertheless, the aerodynamic coefficients and recirculation length are not sufficiently sensitive to the grid number in the spanwise direction. By comparing the results, it can be concluded that suitable and reliable LES results can be obtained when the radial growth rate is 1.03 or 1.05, the circumferential grid number is 160, 200, or 240, and the spanwise grid number is 64. A radial growth rate 1.05, circumferential grid number 160, and spanwise grid number 64 are recommended to reduce the grid amount and further improve the efficiency.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.75-87
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• 1996

This review is presented under the following headings: 1.Introduction 1.1 Brief review of the properties of AlN 1.2 Historical survey of work on ceramic and single crystal AlN 2.Thermochemical background 3.Crystal growth 4.Doping 5.Potential applications and future work The known properties of AlN which make it of interest for various are discussed briefly. The properties include chemical stability, crystal structure and lattice constants, refractive indices and other optical properties, dielectric constant, surface acoustic wave velocity and thermal conductivity. The history of work in single crystals, thin films and ceramics are outlined and the thermochemistry of AlN reviewed together with some of the relevant properties of aluminium and nitrogen; the problems encountered in growing crystals of AlN are shown to arise directly from these thermochemical relationships. Methods have been reported in the literature for growing AlN crystals from melts, solution and vapour and these methods are compared critically. It is proposed that the only practicable approach to the growth of AlN is by vapour phase methods. All vapour based procedures share the share the same problems: $.$the difficulty of preventing contamination by oxygen & carbon $.$the high bond energy of molecular nitrogen $.$the refractory nature of AlN (melting point~3073K at 100ats.) $.$the high reactivity of Al at high temperatures It is shown that the growth of epitactic layers and polycrystalline layers present additional problems: $.$chemical incompatibility of substrates $.$crystallographic mismatch of substrates $.$thermal mismatch of substrates The result of all these problems is that there is no good substrate material for the growth of AlN layers. Organometallic precursors which contain an Al-N bond have been used recently to deposit AlN layers but organometallic precursors gave the disadvantage of giving significant carbon contamination. Organometallic precursors which contain an Al-N bound have been used recently to deposit AlN layers but organometallic precursors have the disadvantage of giving significant carbon contamination. It is conclude that progress in the application of AlN to optical and electronic devices will be made only if considerable effort is devoted to the growth of larges, pure (and particularly, oxygen-free) crystals. Progress in applications of epi-layers and ceramic AlN would almost certainly be assisted also by the availability of more reliable data on the pure material. The essential features of any stategy for the growth of AlN from the vapour are outlined and discussed.

• Applied Biological Chemistry
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• v.4
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• pp.29-32
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• 1963

The Gibberellin is applied to partial fruit trees, vegetables and flowers, but there is only a few information on the components of the effect of Gibberellin on these higher plants. There is no any information on the effect of Gibberellin, Urea and Sucrose mixed liquid on the plant components. So this mixed liquid and gibberellin spraied to the soybean sprout and observed growth velocity variety of some nutrients. Growth velocity, weight, Amino acid contents and fat contents of mixed plot and gibberellin plot are almost same. Mixed liquid plot's sugars and crude proteins contents in a little much than gibberellin plot, but mixed liquid plot's Ascorbic acid contents is a little less than gibberellin plot.

• Clinical and Experimental Pediatrics
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• v.53 no.7
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• pp.759-765
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• 2010

Purpose: This study evaluated the clinical manifestations of and risk factors for pituitary insufficiency in children and adolescents with Rathke's cleft cysts. Methods: Forty-four patients with Rathke's cleft cysts younger than 19 years who visited Seoul National University Children's Hospital between January 1995 and September 2009 were enrolled. Rathke's cleft cysts were confirmed histologically through an operation in 15 patients and by brain magnetic resonance imaging (MRI) in 29 patients. The clinical, hormonal, and imaging features were reviewed retrospectively. Results: The clinical presentation of symptomatic patients was as follows: headache (65%), endocrinopathy (61%), and visual disturbance (19%). Endocrinopathy included central precocious puberty (18%), diabetes insipidus (14%), general weakness (11%), and decreased growth velocity (7%). After surgery, hyperprolactinemia resolved in all patients, but growth hormone insufficiency, hypothyroidism, and diabetes insipidus did not improve. Pituitary insufficiency except gonadotropin abnormality correlated significantly with severe headache, visual disturbance, general weakness, and cystic size. Suprasellar extension of cysts and high signals in the T2-weighted image on brain MRI were related to hypothyroidism, hypocortisolism, and diabetes insipidus. Multivariable linear regression analysis showed that only general weakness was a risk factor for pituitary insufficiency ($R^2$=0.549). Conclusion: General weakness is a risk factor for pituitary insufficiency in patients with Rathke's cleft cysts. When a patient with a Rathke's cleft cyst complains of general weakness, the clinician should evaluate pituitary function and consider surgical treatment.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.43.3-44
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• 2015

We analyze the clustering of large scale structure in the Universe in a model independent method, accounting for anisotropic effects along and transverse to the line of sight. A large sample of 690,000 galaxies from The Baryon Oscillation Spectroscopy Survey Data Release 11 are used to determine the Hubble expansion H, angular distance D_A, and growth rate GT at an effective redshift of z=0.57. After careful bias and convergence studies of the effects from small scale clustering, we find that cutting transverse separations below 40 Mpc/h delivers robust results while smaller scale data leads to a bias due to unmodelled nonlinear and velocity effects. The converged results are in agreement with concordance LCDM cosmology, general relativity, and minimal neutrino mass, all within the $68{\backslash}%$ confidence level. We also present results separately for the northern and southern hemisphere sky, finding a slight tension in the growth rate -- potentially a signature of anisotropic stress, or just covariance with small scale velocities -- but within $68{\backslash}%$ CL.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.2
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• pp.139-146
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• 2000

Cavitation can occur in pipes when liquid is moving at high velocity, especially at pittings where the smooth bore of the pipe is interrupted. The effect is usually to produce pitting on the downstream side of the turbulence. However, stress corrosion cracking behavior under cavitation erosion-corrosion was neatly unknown. In this study, therefore, some were investigated of stress corrosion cracking behavior, others were stress corrosion cracking behavior under cavitation erosion-corrosion of water injection. And datas obtained as the results of experiment were compared between the two. Mainresult obtained are as follows: 1) Stress corrosion cracking growth rate of heat affected zone under cavitation erosion-corrosion becomes most rapid, and stress intensity factor $K_1$becomes most high. 2) Stress corrosion cracking growth mechanism by cavitation erosion-corrosion is judgement on the strength of the film rupture model and the tunnel model. 3) The range of potential as passivation of heat affected zone is less noble than that of base metal, and that value is smaller. 4) Corrosion potential under cavitation erosion-corrosion in loaded stress is less noble than that of stress corrosion, and corrosion current density is higher.