• The Journal of Natural Sciences
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• v.11 no.1
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• pp.113-117
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• 1999

Treatments with increased amount of nitrogen fertilizer had less calcium content than those of conventional fertilization in 'Starkrimson' apple fruits. When $CaCl_2$ solution was applied as tree spray, treatment of conventional fertilization had increased fruit calcium content and decreased occurrence of spotted disorders. Better in increasing fruit calcium content was secured in treatment of conventional nirtogen fertilization. The irrigation effect to sandy loam soil where 'Fuji' apple fruits were planted were observed in fruit enlargement and increase of calcium content in leaves and fruits.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.6 s.113
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• pp.40-50
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• 2006

This study was carried out to examine the tree-ring growth characteristics of Zelkova serrata Makino after replanting, for the built-up planting founds for stability of landscaped trees in the reclaimed land from the sea. the factors, many affecting the growths of Zelkova serrata Makino, were the replanting stress and drought. The growth reduction due to replanting and drought occurred in the replanting year and the following year. The mean sensitivity(year-to-year variation) and the coefficient of variation(tree-to-tree variation in a certain year) in tree rings of Zelkova serrate Makino, were higher in the poor soil sites than in the favourable soil ones. And the poor soil sites were the filled ground of improve soil and the covered ground of improve soil and the top ground of big mounding than mounding ground sites, especially soil hardness, alkali soil, high $Na^+\;and\;K^+,\;low\;Ca^{++}\;and\;Mg^{++}$ and T-C were the most crucial. We suggest technique development of the built-up planting ground for stability in the reclaimed land from the sea. The built-up planting grounds in reclaimed land from the sea, should be considered for the use of fair soil with the physical and chemical soil properties, -high level foundation of planting ground, and the prevention of disturbed soil-.

• Wind and Structures
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• v.24 no.3
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• pp.287-306
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• 2017

In the present study, a new assessment simulation of ride safety based on a new wind-traffic-pavement-bridge coupled vibration system is developed considering stochastic characteristics of traffic flow and bridge surface. Compared to existing simulation models, the new assessment simulation focuses on introducing the more realistic three-dimensional vehicle model, stochastic characteristics of traffic, vehicle accident criteria, and bridge surface conditions. A three-dimensional vehicle model with 24 degrees-of-freedoms (DOFs) is presented. A cellular automaton (CA) model and the surface roughness are introduced. The bridge deck pavement is modeled as a boundless Euler-Bernoulli beam supported on the Kelvin model. The wind-traffic-pavement-bridge coupled equations are established by combining the equations of both the vehicles in traffic, pavement, and bridge using the displacement and interaction force relationship at the patch contact. The numerical simulation shows that the proposed method can simulate rationally useful assessment and prevention information for traffic, and define appropriate safe driving speed limits for vulnerable vehicles under normal traffic and bridge surface conditions.

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.204-219
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• 2021

This study was conducted to investigate and analyze the characteristics of the plant community structure of vegetation distributed on the western slope and ridge connecting Mt. Noja to Mt. Gara. This basic research was executed not only to restore and manage forest vegetation, but also to monitor the trend of change in the long term. As a result of classifying the communitise in 86 survey quadrats, the Pinus thunbergii-Platycarya strobilacea comm. and P. thunbergii-P. densiflora comm. were distributed around the lowlands. The Carpinus tschonoskii-Deciduous broad-leaved comm., Styrax japonicus-Deciduous broad-leaved comm., Acer pictum subsp. Mono-Deciduous broad-leaved comm., Deciduous broad-leaved comm., and Zelkova serrata comm. appeared in the valley and all stone areas. Quercus serrata comm., Q. serrata-S. japonicus comm., S. japonicus-Carpinus cordata comm., Euonymus oxyphyllus comm. were classified as being distributed on steep slopes with relatively high altitude. According to the succession trend of the forest, evergreen conifers will be transition to deciduous broad-leaved trees. However, deciduous broad-leaved arboreous forests, such as Carpinus tschonoskii, zelkova serrata, and Acer pictum subsp. Mono, were considered to maintain their current succession stage because not only the stratified structure was developed over about 50 years tree age, but also ecologically stabilized. As environmental factors, it was analyzed that altitude, pH, content of clay and silt, Mg⁺⁺, Ca⁺⁺, etc. directly or indirectly affect the distribution of plant communities.

• Journal of Bio-Environment Control
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• v.17 no.3
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• pp.231-237
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• 2008

Objective of this research was to investigate the effect of calcium concentrations in the fertilizer solution on growth and development of Ca deficiency in 'Maehyang' strawberry (Fragaria $\times$ ananassa Duch.). The margins of the youngest leaves were scorched and they developed a cupped shape as they were expanded in Ca deficient plants. The vein area of the youngest leaves became brown when the deficiency became severe. The quadratic responses were observed in dry weight production to elevated Ca concentrations in fertilizer solutions with the highest growth in 4.5 mM treatment. The regression equation was y=2.4026+1.0209x-$0.098x^2$ $(R^2=0.3546^{***})$. However, tissue Ca contents increased lineally as the Ca concentrations in fertilizer solutions were elevated (y=1.2108+0.1333x, $R^2=0.9189^{***}$). In changes of the fresh weight and Ca concentrations in petiole sap, fresh weight production showed quadratic responses to elevated Ca concentrations in fertilizer solution, but Ca concentration increased lineally. The equations in changes of fresh weight and Ca concentrations were y=9.273+4.882x-$0.4245x^2$ $(R^2=0.4935^{***})$ and y=52.311+3.2917x $(R^2=0.6918^{***})$, respectively. When the concentration of calcium at which plant growth was retarded by 10% is regarded as critical concentration level, the calcium contents based on dry weight of above ground plant tissue and in petiole sap should be in the range between 1.6 to 2.25% and 63 to $79mg{\cdot}kg^{-1}$, respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.1
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• pp.75-86
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• 2002

This study was conducted to analyze the change of soil characteristics effect on the condition of urban forest in Sasang parti located near Sasang Industrial Complex. The results of this study are as follows; 1. Soil hardness is increasing from the area of forest, to the entrance, to facilities in that order. Soil acidity pH4.19∼4.23 in Sasang park indicated a high acidity condition. High levers of K, Na, Mg, Ca are shown in the areas composed of high soil hardness. 2. Pinus thunbergii in the overstory tree layer, Alnus japonica in the understory tree layer, and Rhus sylvestris in the shurb layer are shown respectively as dominant species based on the ground survey and the compution of important value. Pinus thunbergii is decreasing, while Alnus japonica and increasing. 3. Oplismenus undulatifolius which has a strong tolerance for air pollution, is shown as a dominant species of herbaceous plants in Sasang park. There are 10 species of Harbaceous in Sasang park compared to 20 species in Molundae park. This shows that deversity in herbaceous plants are imported by air pollution. 4. Species diversity indices of Sasang park is 0.8738∼0.9700 compared to 1.0817∼ 1.233 in Molundae park is due to the good condition of soil environment in addition to air pollution effects. 5. The vitality of Pinus thunbergii is 16.41∼20.42ER in Sasang park, and 12.42∼ 16.81ER, in Molundae park. This shows that tree vitality are impacted by soil characteristics. The regression analysis between tree vitality and soil environment shows the effects of is soil hardness, soil moisture, soil acidity, K, Na, Mg, Ca.

• Advances in concrete construction
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• v.11 no.5
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• pp.419-428
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• 2021

The pH of cement-based materials (CBMs) is an important factor for their durability, sustainability, and long service life. Currently, the use of supplementary cementitious materials (SCMs) is becoming mandatory due to economic, environmental, and sustainable issues. There is a decreasing trend in pH of CBMs due to incorporation of SCMs. The determination of numerical values of pH is very important for various low and high volume SCMs blended cement mortars for the better understanding of different defects and durability issues during their service life. In addition, the effect of cement hydration and pozzolanic reaction of SCMs on the pH should be determined at initial and later ages. In this study, the effect of low and high-volume fly ash (FA) and ground granulated ballast furnace slag (GGBFS) cement mortars in different curing conditions on their pH values has been determined. Thermal gravimetric analysis (TGA) was carried out to support the findings from pH measurements. In addition, thermal conductivity (k-value) and strength activity indices of these cement mortars were discussed. The results showed that pH values of all blended cement mortars were less than ordinary Portland cement (OPC) mortar in all curing conditions used. There was a decreasing tendency in pH of all mortars with passage of time. In addition, the pH of cement mortars was not only dependent on the quantity of Ca(OH)₂. The effect of adding SCMs on the pH value of cement mortar should be monitored and measured for both short and long terms.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.6
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• pp.29-36
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• 2008

This study examined the de-icing agents' stresses on Pinus strobus and Pinus thunbergii by chlorophyll fluorescence analysis. The assumption of this study was that photosynthetic efficiency was changed by de-icing agents applied onto highways in winter by altering the concentration of the de-icier, types of de-icer and leaf surface coating liquid application. The practical purpose of this study was to investigate the de-icing gents stresses on Pinus strobus by the highway area where de-icing agents were used frequently and to discover out minimizing stratages to prevent further damages. or this simulation study, a sample plot was established in Bogae-myeon, Anseong, Gyeonggi-do and Pinus strobus and Pinus thunbergii were planted for the examination in April, 2005. Five types of de-icing agents - NaCl, $CaCl_2$, T product(NS40:low cWoride de-icer type), NaCl+$CaCl_2$ and T product+$CaCl_2$ - were selected and the their concentration was altered to 0%, 5%, and 9%. Five types of de-icing agents were applied to both trees treated by a leaf surface coating liquid and trees not treated by leaf surface coating liquid. For the fluorescence analysis, the leaf surface coating liquid, which was diluted by 10 times, was sprkinkled onto the two tree species three days prior to gathering samples. Sample leaves from the two tree species were gathered at 10 o'clock in the morning of mid-August, 2006 and brought to the laboratory within three hours to be dipped in different concentrations (0%, 5%, or 9%) of the five de-icing agents for two minutes. Then the eaves were placed on the filter paper dipped in each solution on a petri dish, sealed with polyethylene film and kept in a growth chamber at $22^{\circ}C$ for 72 hours. Out of the growth chamber, the leaves were treated with a chorophyll fluorescence reaction analyzer for 30 minutes to measure the initial light acceptance rate(Fo), maximum light acceptance ate(Fv/Fm), light acceptance usage(F' q/F' m) and optical electron delivery coefficient(qP). As a result, Pinus strobus' initial light acceptance rate(Fo) decreased as T product and NaCl increased in concentration, and $Cal_2$ did not reduce much with the eaf surface coating liquid application. Maximum light acceptance rate(Fv/Fm) and light acceptance usage(F' q/F' m) decreased sharply as T product and NaCl increased in concentration and NaCl+$CaCl_2$ and T product+$CaCl_2$ did not reduce much with leaf surface coating liquid application. Optical electrons delivery coefficient (qP) decreased as T product increased in concentration on trees without the leaf surface coating liquid application and all other de-icing agents did not show much reduction. As for Pinus thunbergii, the initial light acceptance rate(Fo) decreased as T product increased in concentration, but the maximum light acceptance rate(Fv/Fm) was not reduced much by changes in concentration. light acceptance usage(F' q/F' m) decreased as NaCl increased in concentration and optical electron delivery coefficient(qP) decreased as NaCl increased in concentration in both with and without leaf surface coating liquid application. In conclusion, it was possible to plant Pinus strobus if spraying leaf surface coating liquid or cleaning deicing salt to prevent the damage caused by deicing agents was more economical than replacing the trees. If not, it was better to plant Pinus thunbergii. Another way to decrease the deicing gents stresses of landscape plants would be planting the trees further away from the roads even though it might take longer period to display its planting functions.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.680-685
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• 2012

The objective of the experiment was to investigate the effect of two growing areas in the greenhouse on the plant growth characteristics, physiological responses and yield attributes of the 'Cupra' sweet pepper. Two growing areas of the greenhouse were as follows, central part area (CA) and north part area (NA). Daily average temperature of the CA was $1.6^{\circ}C$ higher than those of NA. Plant height, number of internode, and SPAD value in the CA were significantly higher than NA both six weeks and twelve weeks after planting. Net photosynthesis of the sweet pepper leaves of the CA was significantly higher than those of NA. The total fruit yield of the sweet pepper was 20% higher in plants grown for CA than that of NA. These results suggest that air temperature in the greenhouse influenced plant growth characteristics, net photosynthesis and total yield of sweet pepper whether pepper plants were grown as CA or as NA.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.6
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• pp.62-76
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• 2001

This study is to offer the basic information and materials for the restoration of the urban forest and the ecologically healthy and continuous green belt through the investigation and the analysis on the vegetation in Hwasan Park, Chonju-City. The flora of Hwasan Neighborhood park was composed of 86 families 230 genera, 261 species, 35 varieties, 1 formae or 298 Taxa. Among them, calculation of Pte-Q Index represented 0.60, Fisher's Index. Some characteristics of the plants in this area have represented such as Th-D1-R5 type in biological type, erect form(64.6%) in growth type, 30 taxa in naturalized plants. The life form spectra investigated from Hwasan neighborhood park was recognized as the following M"17.4%, N:11.4%, E:0.3%, Ch:0%, H:29.8%, G:6.7%, HH:0%, Th:34.2%. By the Z-M method 5 plant communities and 3 afforestation were recognized; Quercus variabilis community, Q.acutissima community, Q.serrata community, Sorbus alnifolia community, Pinus densiflora community, P.rigida afforestation, Robinia pseudo-acacia afforestation and Larix leptolepis afforestation. The actual vegetation map constructed on the grounds of the communities classified and other data. The pattern of successional trend of tree species might be suggested: L. leptoleipis, P. rigida and P. densifloralongrightarrowQ.variabilis and Q.acutissimalongrightarrowS.alnifolia and Q.serratalongrightarrowCarpinus tschonoskii community. Three measurements of species diversity (richness index(SR), Shannon-Wiener index(H'), evenness index(J')) and their relationship with community type were studied in the surveyed plant communities. Q.serrata community was higher in SR, H', J' than the other communities, whereas R.pseduo-acacia afforestation was low. Finally, The vegetation of the Hwasan neighborhood park must not allowed any more. Nothing ca be better than native states in preserving the ecosystems.tems.