• The Korean Journal of Ecology
• /
• v.15 no.3
• /
• pp.311-328
• /
• 1992

In other to classify calcicoles and calcifuges and calcifuges within plant communities occurring on limestone and granite soils in chungbuk province, korea, soil propertile, constancy for species by prsence or absence, and ratios of soluble to insoluble $Ca^{2+}$ and $Mg^{2+}$ were investigated. In the limestone soils ph values and $Ca^{2+}$ and $Mg^{2+}$ content, ranging 7.26 ~7.48, 5.32~7.37 mg $Ca^{2+}/g$ and 0.42~0.62 mg $Mg^{2+}/g$, respectively, were higher than those in the granite soil with ph 5.76, 1.03mg $Ca^{2+}/g$ and 0.24mg $Mg^{2+}/g$. species with high constancy in the 5 communities were classified into three groups; species group a(29~36% of total number of species) was composed of species occuring on the granite soil; group c(16~24%) is commonly distributed throughout both soils. Ratios of soluble to insoluble $Ca^{2+}$ and $Mg^{2+}$ ranged from 0.1 to 81.3 in the group a, 0.2 to 0.8 in the group b and 0.2 to 8.7 in the group c. species within each group can be divided into two groups based on the values of the ratio, below or above 1.0. consequently, each of the group a and c was classified again into two groups; the group a1 and c1 with the ratio of above 1.0 and the group a2 and c2 withbelow 1.0 but the ratio could not further subdivide the group b. from these results it was proposed that plants of the group a1 were termed as obligate calcicoles, the group b as obligate calcifuges, the group c1 as facultative calcicoles, the group c2 as facultative calcifuges and the group a2 as avoiding calcifuges.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.20 no.2
• /
• pp.13-35
• /
• 2017

This study was carried out to analyze vegetation structure and change of the disturbed area in forest ecosystem(FE), riparian ecosystem(RE) and coastal ecosystem(CE) related to Regional Ecological Network at Chungnam province through constancy and dominance analysis, species diversity index, similarity index and canonical correlation analysis. Data were collected from April to October in 2015. As a result of constancy and dominance analysis of forest disturbed area, non-effective species(NES) was 30 species(17.0%), exported species(ES) was 98 species(55.7%) and imported species(IS) was 48 species(27.3%) among the total 176 species, respectively. In riparian disturbed area with total 139 species, there were 16 NES(11.5%), 98 ES(70.5%) and 25 IS(18.0%) respectively. In coastal disturbed area with 140 species, there were 20 NES(14.3%), 88 ES(62.9%) and 32 IS(22.9%) respectively. In all types of disturbed areas, the ratio of ES was higher than IS. As a result of species diversity, species richness and shannon's diversity index of disturbed area decreased in all kinds of crown strata such as tree, subtree, shrub and herb layer compared to the control area. As a result of similarity index, that of each type between control site and disturbed site was 0.374 in FE, 0.329 in CE and 0.259 in RE in the order. As a result of the CCA analysis, the number of present species, vine plants ratio and exported species ratio in disturbed area of FE and RE were decreased, and the naturalized plant ratio, imported species ratio and herb ratio were increased. But environmental factors of CE were not shown any clear tendency. In conclusion, many species occupied in control site disappeared into the disturbed area, and the naturalized plants and herb species were abundantly imported in the area. Therefore, it was considered that this study could be applied to the development of long-term and short-term ecological restoration techniques in view of vegetation changes.

• Korean Journal of Environment and Ecology
• /
• v.11 no.3
• /
• pp.334-351
• /
• 1997

To study restoration model of evergreen broad-leaved forests in warm temperate region, vegetation structure was studied at Wando(Island) as a case study. Quercus acuta was a dominant species at evergreen broad-leaved forests in Wando(Island). Majority of evergreen broad-leaved forests was a thirty years old coppice forest. Reforested vegetation and deciduous broad-leaved forests was developed at a mid-slope districts and a piedmont. Deciduous broad-leaved forestsconsisted of Quercus serrata, Carpinus tschonoskii, Carpinus coreana, etc., was developed at a ridge and higher districts. Evergreen broad-leaved woody plants were growing at a forest floor of deciduous broad-leaved forests. The species over sixty percent of constanty ratio in forty seven plots were Ligustrum japonicum, Trachelospermum asiaticum var. intermedium, Quercus acuta and Eury japonica. The vascular plants in the Wando(Island) was summarized as 488 taxa which composed as 101 families, 321 genus, 426 species, 56 varieties, 5 forms and 1 hyvrid. Evergreen broad-leaved woody stecies was 32 taxa which composed as 23 genus, 30 species and 2 varieties. The species such as Liliope platyphylla of Liliaceae and Pueraria thunbergii of Leguminosae, etc. was recorded as the highest values for their widely distribution in the areas. On the contrary, and forty taxa of plants such as Viburnum erosum of Caprifoliaceae, Traceholospermum asiaticum var. intermedium was recorded as over 50% of constancy ratio. Two hundred and nine taxa of plants such as Juglans manshurica of Juglandaceae, Cornus walteri of Cornaceae and Rodotypos scandens of Rosaceae, etc. was showed the specific trends due to long-term artificial disturbance. The forest of Pinus thunbergii showde the highest species diversities(155 species per 600m$^{2}$), while the Cinnamomum japonicum-Tracheolospermum asiaticum var. intermedium community showed the lowest species diversities(23 species per 600m$^{2}$).

• 전기의세계
• /
• v.28 no.9
• /
• pp.51-59
• /
• 1979

The forming and design method of D.C thyristor chopper circuit for DC Series motor control is suggested, ard the computation method of thyristor commutaing element's, value which makes it all the more important, is possible. Also the trigger circuit was dealt with. In this paper, in order to control the duty cycle, the duty time is kept on constancy and variable chopping frequency was adopted. By above mentioned circuit design method, the D.C thyristor chopper circuit was implemented and tested. In this circuit, the result of D.C motor control was good and reliable. The relation between the $K_{d}$ and the ratio of input-output current, or the characteristic of speed was varied lineary at the range 0.1 ~ 0.9 of duty cycle. This confirms the fact that D.C to D.C power conversion which is the merit of chopper control is operated most likely a transformer.ormer.

• Textile Coloration and Finishing
• /
• v.27 no.1
• /
• pp.1-10
• /
• 2015

The aim of the current study is to identify the dimerization and decomposition kinetics of the F-$D_M$ type. The regeneration of F-VS from $F_iF_j-D_M$ or the reversibility of the dimerizations were investigated. The order of real rate constants of the dimerization('$K_D{^{ij}}$) would seem to be similar to that of rate constants of a dimerization($K_D{^{ij}}$) for VS dyes at a given pH because of the constancy of the equilibrium constants($K_a{^j}$-value). The reverse reactions of the $D_M$ types are appeared to occur in two steps, the deprotonation of ${\alpha}$-carbon of the $D_M$ types and disproportionation. The ratio of the decomposition of the $D_M$ type to F-Hy and F-VS appears to be related with the ratio of $K_i/K_j$. Similarities were also found among various other reactions, including homo- and mixed dimerization. VS dyes undergoing fast hydrolysis have difficulty in forming a dimer. The higher the reactivity with cellulose or hydroxide ion, the smaller the dimerization. The easiness of the dimerization was thus found to be inversely proportional to the rate of hydrolysis.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.45 no.1
• /
• pp.1-5
• /
• 2000

Leaf area is critical for crop light interception, and thereby has a substantial influence on crop yield. This experiment was conducted to characterize the development of soybean [Glycine max (L.) Merr.] leaf area. Plastochron index and leaf relative growth rate of Jackson was contrasted with the PI416937, which also has demonstrated tolerance to drought. First, plastochron ratio (PR) and plastochron index (PI) were evaluated in greenhouse to compare the leaf growth rate between two genotypes under well-watered condition. There was reasonable constancy of PR between two genotypes. The PR means of Jackson and PI416937 were 0.41 and 0.44, respectively. A fairly smooth increase of PI during vegetative stage was observed. Second, the relative growth rates were graphed against leaf area, normalized with respect to final leaf area, under well-watered and water-deficit conditions. Leaf growth was sustained longer in well-watered condition than water-deficit condition and there was a sizable proportion of leaves which was ceased earlier their growth in water-deficit condition compared to well-watered condition. The leaf relative growth rate of Jackson until leaves had completed at 45% of their growth during water deficit period was higher than that of PI416937.

• School Mathematics
• /
• v.5 no.4
• /
• pp.421-440
• /
• 2003

It is difficult for the learner to understand completely the ratio concept which forms a basis of proportional reasoning. And proportional reasoning is, on the one hand, the capstone of children's elementary school arithmetic and, the other hand, it is the cornerstone of all that is to follow. But school mathematics has centered on the teachings of algorithm without dealing with its essence and meaning. The purpose of this study is to analyze the essence of ratio concept from multidimensional viewpoint. In addition, this study will show the direction for improvement of ratio concept. For this purpose, I tried to analyze the historical development of ratio concept. Most mathematicians today consider ratio as fraction and, in effect, identify ratios with what mathematicians called the denominations of ratios. But Euclid did not. In line with Euclid's theory, ratio should not have been represented in the same way as fraction, and proportion should not have been represented as equation, but in line with the other's theory they might be. The two theories of ratios were running alongside each other, but the differences between them were not always clearly stated. Ratio can be interpreted as a function of an ordered pair of numbers or magnitude values. A ratio is a numerical expression of how much there is of one quantity in relation to another quantity. So ratio can be interpreted as a binary vector which differentiates between the absolute aspect of a vector -its size- and the comparative aspect-its slope. Analysis on ratio concept shows that its basic structure implies 'proportionality' and it is formalized through transmission from the understanding of the invariance of internal ratio to the understanding of constancy of external ratio. In the study, a fittingness(or comparison) and a covariation were examined as the intuitive origins of proportion and proportional reasoning. These form the basis of the protoquantitative knowledge. The development of sequences of proportional reasoning was examined. The first attempts at quantifying the relationships are usually additive reasoning. Additive reasoning appears as a precursor to proportional reasoning. Preproportions are followed by logical proportions which refer to the understanding of the logical relationships between the four terms of a proportion. Even though developmental psychologists often speak of proportional reasoning as though it were a global ability, other psychologists insist that the evolution of proportional reasoning is characterized by a gradual increase in local competence.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.8 no.3
• /
• pp.132-140
• /
• 2006

Forest vegetation classification and species composition of Mt. Ilwol, Yeongyang-Gun, Korea, were studied combining the Braun-Blanquet approach with numerical syntaxonomical analyses (TWINSPAN). Vegetation types and various ecological characteristics such as flora, constancy classes, species ratio of life-form, species diversity and importance value were analyzed. Sixty-eight samples were taken from a $100m^2$ square plot each. Forest communities were identified as two great types: arid landform of mountainside (AM) and humid fertility of piedmont and valley (HP). The former was divided into 3 communities (Rhododendron mucronulatum, Quercus variabilis, Hosta capitat community) and 2groups, and the latter into 3 communities (Tilia amurensis, Vitis coignetiae, Philadelphus schrenckii community) and 2 groups. Vegetation was classified into 8 units. Floristically, the most represented family was Compositae with 26 species. Species with percentage constance degree of more than 61% was Quercus mongolica (72.1%, IV); Carex siderosticat (III) and Fraxinus rhynchophylla (III) were 50.0 and 41.1%, respectively. Life-forms species ratios for trees, subtrees, shrub, vines, grominoids, forbs and ferns were 18.5, 5.7, 14.9, 6.6, 8.8, 42.4 and 3.1%, respectively, PH type showed from $1.70{\pm}0.50\;to\;1.97{\pm}0.57$ and AM type was from $1.40{\pm}0.18\;to\;1.62{\pm}0.20$ in species diversity; therefore, the former type showed higher species diversity than the latter, According to importance value analysis, Pinus densiflora, Quercus mongolica and Q. variabilis were higher in the tree layer, Q. mongolica in the subtree layer, Fraxinus sieboldiana, R. schlippenbachii, etc. in the shrub layer and Carex siderosticta, Carex humilis, etc. in the herb layer.

• Journal of Microbiology and Biotechnology
• /
• v.13 no.5
• /
• pp.673-679
• /
• 2003

Glutamine and urea, abundant in body fluids or plasma, yield net ammonium ions upon hydrolysis by ${\gamma}-glutamyl$ transpeptidase (${\gamma}-GTP$) and urease, respectively, and these two enzymes are largely produced from Helicobacter pylori. To investigate bacterial potential of ammonium production, we first quantified those in whole-cell systems and found that the relative ratio of their amounts varied greatly, especially with pH values and the cell's aging. During the H. pylori cultivation, the ratio appeared to be inversely proportional to each other, showing a progressive increase of the ${\gamma}-GTP$ with decreasing of the urease. Under the urease-defective conditions due to low pH or coccoids, the bacterial cells still possessed a considerable amount of ${\gamma}-GTP$, which was found exclusively in the external compartment, therefore, the cell's ammonium production was found to be solely dependent upon glutamine, and the external ammonium concentration was constant without any contribution of urea concentration. Such ammonium constancy would definitely have an adverse effect on the host, because of its absolute requirement for vacuolar degeneration by H. pylori VacA, maximized at approximately 10 mM $NH_4Cl$. It was also found that, by using the metal-saturated membrane vesicles, ammonium ions were likely to be involved in the pH-dependent cation-flux across the H. pylori membrane, where the role of ${\gamma}-GTP$ in ammonium homeostasis around cells was suggested, especially under the hostile conditions against H. pylori.

• Journal of Astronomy and Space Sciences
• /
• v.12 no.1
• /
• pp.21-29
• /
• 1995

The $\beta$ Lyrae-type eclipsing binary AW Cam was observed photoelectrically in three wavelength regions. The obtained UBV light curves of AW Cam were analyzed with two separate modes(mode 2 for detached systems and mode 5 for semi-detached ones) of the Wilson-Devinney binary mode. It is intended to resolve the discrepancy in AW Cam system that the photometrio mass ratio (q=0.21) derived by Russo and Milano (1983) is not consistent with the spectroscopic result (q=0.43) by Mammano et al.(1967). Our photomtric solutions derived with mode 2 are fitted better to the observed light curves than those of mode 5, supporting that AW Cam may be not a normal semi-detached system but a detached one. Three dimensional Roche configuration of AW Cam system calculated with the derived mass ratio (q=0.43) reveals that the less massive secondary with the confined within its inner Roche lobe, while the more massive rimary is in marginally contact. From the Roche geometry, the constancy of the orbital period and other photometric evidences of AW Cam, it is provisionally concluded that the system is an unevolved detached binary in is provisionally concluded that the system is an unevolved detached binary in the phase of case A evolution toward 'contact phase' rather than and evolved one in 'broken-contact phase' suggested by Giuricin and Mardrossian (1981).