• Journal of Plant Biology
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• v.13 no.1
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• pp.47-55
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• 1970

In order to approach a reasonable method for the indirect estimation of the productivity in terrestrial plants, allometric method was studied with herbs, such as Boenmeria frutescens and Hibiscus mutabilis, and scrubs, such as Robinia pseud oacacia and Morus alba f. Hchiroe. Allometric relations between D230H, square of the stem(or shoot) diameter(D30) on 30cm height above ground multiplied by stem length(H), and the amount of the stem(Ws), orof the leaves per stem, were fitted to each material plant with linear regression. The allometric coefficient in relation of D230H to Ws was approximated between scrubs having different life form, and the allometric function in relation of DF2 to WL was common between herbs in spite of having different growth habitat. As the allometries between D230H and Ws or WL were changeable with the seasonal change it funciton should be calculated repeatedly whenever investigating the standing crop of such community. It is able to utilize an indirect value of D30 obtained from the allometry between D30 and H because direct measurement of D30 in the field is accompanied by troublesome and waste of much time.

• Journal of Navigation and Port Research
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• v.29 no.8 s.104
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• pp.667-671
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• 2005

This study was carried out to examine the prediction of ship's manoeuvrability in initial design stage. New parameter representing basic hull form and stem shape were proposed. Captive model test were carried out to investigate the correlation coefficient between hydrodynamic coefficient and hull parameter. The results showed which parameter are positive correlation with hydrodynamic coefficient. Moreover correlation was examined between stem hull shape and ship's manoeuvrability. New empirical formulas for hydrodynamic coefficients were proposed These results can be used to predict a ship's manoeuvrability in initial design stage.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.6
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• pp.794-802
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• 2018

The ice resistance series charts for icebreaking ships were developed through a series of systematic model tests in the ice tank of the Korean Research Institute of Ship and Ocean Engineering (KRISO). Spencer's (1992) component-based scaling system for ship-ice model tests was applied to extend the model ship correlations. Beam to draft ratio (B/T), length to beam ratio (L/B), block coefficient ($C_B$) and stem angle (${\alpha}$) were selected as geometric parameters for hull form development. The basic hull form (S1) of twin pod type with B/T of 3.0, L/B of 6.0, $C_B$ of 0.75 and stem angle of $25^{\circ}$ was generated with a modern hull design concept. A total of 13 hulls were designed varying the geometric parameters; B/T of 2.5 and 3.5, L/B of 5.0 and 7.0, $C_B$ from 0.65 to 0.85 in intervals of 0.05, and 5 stem angles from $15^{\circ}$ to $35^{\circ}$. Ice resistance tests were first carried out with the basic hull form in level ice with suitable speed. Four more tests for $C_B$ variations from 0.65 to 0.85 were conducted and two more for beam to draft and length to beam ratios were also performed to study the effect of the geometric parameters on ice resistance. Ice resistance tests were summarized using the volumetric coefficient, $C_V$ ($={\nabla}/L^3$), instead of L/B and $C_B$ variations. Additional model tests were also carried out to account for the effect of the stem angle, ice thickness and ice strength on ice resistance. In order to develop the ice resistance series charts with a minimum number of experiments, the trends of the ice resistance obtained from the experiments were assumed to be similar for other model ship with different geometric parameters. A total of 18 sheets composed of combinations of three different beam to draft ratios and six block coefficients were developed as a parameter of $C_V$ in the low speed regions. Three correction charts were also developed for stem angles, ice thickness and ice strength respectively. The charts were applied to estimate ice resistance for existing icebreaking ships including ARAON, and the results were satisfactory with reasonable accuracy.

• Journal of Korean Society of Forest Science
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• v.73 no.1
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• pp.63-69
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• 1986

In general, the snow injury in forestry is an unusual disaster. The degree of snow injury varies greatly depending on stand density and the local topography. This study was conducted to investigate the snow injury in analyzing the demaged by snow-fall in Jinju, Gyeongsangnamdo. The results obtained were summarized as follow; Among 466 total damaged trees, 425 trees were broken and 41 trees were uprooted, the ratio of damage were 5.22%, 2.49%, 0.92% and 0.2% for Pinus densiflora, Pinus thunbergii, Pinus rigida, Alnus hirsuta respectively. The 95% of the damage trees were in the range of 3 to 11 m for height and in the range of 3 to 20 cm for D. B. H.. The directions of the damage trees had a large influence by direction of the wind, but they shown at high tendency to aspect of the slope relatively. The 82% of the damaged trees ranged from 11 to 24 age. The ratio of broken height ($H_B/H$) indicated that the damage was most frequent in the part of stem as 24%, 45%, 31% in the part of the root collar (0.1), stem (0.2-0.4), crown (0.5-1.0) respectively. In general, trees with stem-form coefficient ($H_B/D$) over 0.7-0.8 are apt to suffer by snow damage. The average of stem-form coefficient of trees in this area was 1.06. Therefore, the ratio of damage was high tendency as 3.14%. These results indicate that it is necessary to apply pertinent tending which will increase in resistance of snow damage. As avalanches from the flank of soil erosion rise in an importance matter in present, it should also be considered to measures for prevention and restoration.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.229-233
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• 2006

Comparison of the grade of raw ginseng and that of red ginseng was investigated. The materials used in this study were Korean ginseng (Panax ginseng C. A. Meyer) and American ginseng(Panax quinquefolium L.) Coefficient of body term, length of main stem and weight of raw ginseng were used as the classifying criteria of the root size and grades. Korean ginseng distinguished the distribution of weight size from that of American ginseng. Korean ginseng distributed largely in middle and large root size, and American ginseng distributed largely in middle and small root size. American ginseng had shorter length of main root, bigger diameter of main root and more number of adventitious roots than Korean ginseng. The quality of Korean ginseng was better than that of American ginseng. In Korean ginseng, high quality of red ginseng above second grade (Jisam) was obtained, but low quality of red ginseng under third grade (Yangsam) in American ginseng. In Korean raw ginseng, the coefficients of body form of middle weight and large weight size were under 0.5, but those of American ginseng was over 0.5. So American ginseng were not adequate to produce good red ginseng. Those factors as length of main root and weight of main root were not significantly influenced on the qualify of red ginseng in both Korean ginseng and American ginseng. Coefficient of body form was leading factor affecting the quality of red ginseng. To improve the quality of red ginseng, coefficient of body form, weight of main root and length of main root were controlled adequately in both Korean ginseng and American ginseng.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.6
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• pp.883-888
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• 2010

This study have goal with conceptual design for Offshore Structures of high pressure control valve for localization. Ball valve for development accomplished with flow analysis based on provision of ANSI B16.34, ANSI B16.10, ANSI B16.25 In order to localize the Offshore Structures high pressure control valve. Numerical simulation using CFD (Computational Fluid Dynamic) in order to predict a mass flow rate and a flow coefficient form flow dynamic point of view. The working fluid assumed the glycerin (C3H8O3). The valve inlet and outlet setup a pressure boundary condition. The outlet pressure was fixed by atmospheric pressure and calculated until increasing 1bar to 10bar. CFD analysis used STAR-CCM+ which is commercial code and Governing equations were calculated by moving mesh which is rotated 90 degrees when ball valve operated opening and closing in 1 degree interval. The result shows change of mass flow rate according to opening and closing angle of valve, Flow decrease observed open valve that equal percentage flow paten which is general inclination of ball valve. Relation with flow and flow coefficient can not be proportional according to inlet pressure when compare with mass flow rate. Because flow coefficient have influence in flow and pressure difference. Namely, flow can be change even if it has same Cv value. The structural analysis used ANSYS which is a commercial code. Stress analysis result of internal pressure in valve showed lower than yield strength. This is expect to need more detail design and verification for stem and seat structure.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1195-1200
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• 2008

This study have goal with conceptual design for Offshore Structures of high pressure control valve for localization. Ball valve for development accomplished with flow analysis based on provision of ANSI B16.34, ANSI B16.10, ANSI B16.25 In order to localize the Offshore Structures high pressure control valve. Numerical simulation using CFD(Computational Fluid Dynamic) in order to predict a mass flow rate and a flow coefficient form flow dynamic point of view. The working fluid assumed the glycerin($C_3H_8O_3$). The valve inlet and outlet setup a pressure boundary condition. The outlet pressure was fixed by atmospheric pressure and calculated until increasing 1bar to 10bar. CFD analysis used STAR-CCM+ which is commercial code and Governing equations were calculated by moving mesh which is rotated 90 degrees when ball valve operated opening and closing in 1 degree interval. The result shows change of mass flow rate according to opening and closing angle of valve. Flow decrease observed open valve that equal percentage flow paten which is general inclination of ball valve. Relation with flow and flow coefficient can not be proportional according to inlet pressure when compare with mass flow rate. Because flow coefficient have influence in flow and pressure difference. Namely, flow can be change even if it has same Cv value. The structural analysis used ANSYS which is a commercial code. Stress analysis result of internal pressure in valve showed lower than yield strength. This is expect to need more detail design and verification for stem and seat structure.

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.429-444
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• 1988

Considering the recent trent toward the development of multiple-use of forest trees, investigations for comprehensive information on these young stands of Hinoki cypress are necessary for rational forest management. From this point of view, 83 sample trees were selected and cut down from 23-ear old stands of Hinoki cypress at Changsung-gun, Chonnam-do. Various stem growth factors of felled trees were measured and canonical correlaton analysis, principal component analysis and factor analysis were applied to investigate the stem growth characteristics, relationships among stem growth factors, and to get potential information and comprehensive information. The results are as follows ; Canonical correlation coefficient between stem volume and quality growth factor was 0.9877. Coefficient of canonical variates showed that DBH among diameter growth factors and height among height growth factors had important effects on stem volume. From the analysis of relationship between stem-volume and canonical variates, which were linearly combined DBH with height as one set, DBH had greater influence on volume growth than height. The 1st-2nd principal components here adopted to fit the effective value of 85% from the pincipal component analysis for 12 stem growth factors. The result showed that the 1st-2nd principal component had cumulative contribution rate of 88.10%. The 1st and the 2nd principal components were interpreted as "size factor" and "shape factor", respectively. From summed proportion of the efficient principal component fur each variate, information of variates except crown diameter, clear length and form height explained more than 87%. Two common factors were set by the eigen value obtained from SMC (squared multiple correlation) of diagonal elements of canonical matrix. There were 2 latent factors, $f_1$ and $f_2$. The former way interpreted as nature of diameter growth system. In inherent phenomenon of 12 growth factor, communalities except clear length and crown diameter had great explanatory poorer of 78.62-98.30%. Eighty three sample trees could he classified into 5 stem types as follows ; medium type within a radius of ${\pm}1$ standard deviation of factor scores, uniformity type in diameter and height growth in the 1st quadrant, slim type in the 2nd quadrant, dwarfish type in the 3rd quadrant, and fall-holed type in the 4 th quadrant.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.357-362
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• 2008

This study have goal with reverse engineering for petrochemistry of high pressure ball valve for localization. Ball valve for development accomplished with flow analysis based on provision of ANSI B16.34, ANSI B16.10, ANSI B16.25 In order to localize the petrochemistry high pressure control valve. Numerical simulation using CFD(Computational Fluid Dynamic) in order to predict a mass flow rate and a flow coefficient form flow dynamic point of view. The working fluid assumed the water($H_2O$). The valve inlet and outlet setup a pressure boundary condition. The outlet pressure was fixed by atmospheric pressure and calculated inlet velocity 5m/s. CFD solver used STAR-CCM+ which is commercial code. The result shows change of mass flow rate according to opening and closing angle of valve. Flow decrease observed open valve that equal percentage flow paten which is general inclination of ball valve. The structural analysis used ANSYS which is a commercial code. Stress analysis result of internal pressure in valve showed lower than yield strength. This is expect to need more detail design and verification for stem and seat structure.

• Journal of Bio-Environment Control
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• v.3 no.1
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• pp.20-27
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• 1994

This study was conducted to improve marketing value and productivity of cucumber which was cultivated with primary scaffold stem type (Mannungcheongjang) and lateral stem type (Sayeup). The results are summarized as follows ; 1. Investigation of fruit setting characteristics to improve cucumber training type was resulted that the fruit-thinning was effective 3 nodes in Mannung- cheongjang and 4 nodes in Sayeup, because of defected yield potential and marketing value. 2. In the matter of early growing stage after training and cucumber quality at different treatment, cucumber weight at flowering curved cucumber and growth analysis of Mannungcheongjang were good in order of horizontal>vertical>slant training. And those of Sayeup were good in order of horizontal >slant> vertical training. 3. Aspect of light reception of cucumber plant in the level of plant height and accumulated leaf area index, vertical and horizontal training are better than slant in Mannungcheongjang, and there is order of horizontal >vertical >slant training in Sayeup. 4. Horizontal training in Mannungcheongjang was superior to any other case In view of cucumber number, productivity, and marketing rate. Therefore, this training was suggest ed of best method in cucumber cultivation.