• Textile Coloration and Finishing
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• v.20 no.4
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• pp.53-59
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• 2008

For the modification of wool surface, wool fabrics treated with oxygen low-temperature plasma(LTP) and dichloroisocyanuric acid(DCCA) were dyed with milling type acid dye. The difference of dyeing properties on modified and control wool fabric were investigated. DCCA treated wool showed that saturation dye uptake and dyeing desorption ratio were higher than LTP treated wool. Dyeing transition temperatures of DCCA and LTP treated wool fabrics were 20$^{\circ}C$ degree lower than control wool fabric. In light color fastness test, DCCA treated wool fabric was 1 grade lower than LTP or control wool fabric.

• Journal of the Korean Ceramic Society
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• v.28 no.6
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• pp.488-494
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• 1991

In this study, the effects of catalyst and DCCA content were investigated in order to determine the optimum conditions of monolithic silica gel formation through sol-gel process. Formamide, oxalic acid, glycerol and dimethylformamide are used as DCCA. To observe the phenomena in drying and heat-treating of gels, we examined structural exchange of gels using FT-IR, TG-DTA and XRD. Monolithic gels were obtained by adding formamide and dimethylformamide as DCCA. According to the heat treatment schedule, silica glass is prepared by heat-treatment up to 1050$^{\circ}C$.

• Journal of the Korean Society of Radiology
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• v.7 no.5
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• pp.347-352
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• 2013

In this study, we analyze the cross correlation between Gamma exposure rates and Rainfall, Hours of daylight, Average wind speed using cross-correlation coefficient ${\rho}_{DCCA}$ and DCCA cross-correlation coefficient(DCCA ${\rho}$) method. Our data are measured simultaneous in Gangneung regional. First, we find the ${\rho}_{DCCA}$ between Gamma exposure rates and Rainfall is Day(3~7days) 0.57~0.48, Month(30days) 0.39, Season(90days) 0.34, Year(360days) 0.26, between Gamma exposure rates and Hours of daylight is Day -0.20~-0.23, Month -0.22, Season -0.17, Year -0.13, between Gamma exposure rates and Average wind speed is Day -0.10~-0.12, Month -0.11, Season -0.05, Year -0.05. Second, our finding is cross- correlation between Gamma exposure rates and Rainfall, is no cross-correlation between Gamma exposure rates and Hours of daylight, Average wind speed.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.497-504
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• 1993

The effect of DCCA (Drying Control Chemical Additives) on the drying of gel was investigated in order to determine an optimum drying condition of mullite precursor through sol-gel process. Aluminium sec-butoxide was synthesized from aluminium foil and then mullite powders were synthesized from Tetra-ethyl-ortho-silicate (TEOS) and the aluminium sec-butoxide. N, N-dimethyl formamide (DMF), Glycerol, 1, 4-Dioxane, and Oxalic acid were used as DCCA. Mullite powders that were calcined at 200, 900, 1100, and $1250^{\circ}C$ for 2hr were analysed by XRD, TG-DTA, FT-IR, and SEM in order to investigate structural change and characteristics of calcined powders. The results of this work showed that the drying time of gel was reduced to about half in the presence of 0.1mol DMF compared with the absence of DCCA and also calcined powders were obtained without remarkable structural change despite of the addition of DCCA.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.43-52
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• 2008

Wool fabric was treated with oxygen low-temperature plasma (LTP) and dichloroisocyanuric acid. The effect of dimensional stability (relaxation shrinkage, hygral expansion, felting shrinkage), tensile strength and elongation, crease recovery, and hand of wool fabric between LTP, DCCA treated wool fabrics and control wool fabric were investigated. SEM photograph showed that a little micro crack was formed on the fiber surface by plasma treatment with hard condition and epicuticle scale was damaged by DCCA treatment. Felting shrinkage, tensile strength and total hand value were much different in each samples.

• The Korean Journal of Applied Statistics
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• v.29 no.7
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• pp.1445-1458
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• 2016

This paper derives a correlation coefficient using detrended cross-correlation analysis (DCCA) method for 59 regional temperature series for 40 years from 1976 to 2015. The average temperature, maximum temperature, and minimum temperature series for 4 year units are analyzed; consequently, we estimated that a temperature correlation exists between the two regions during the unit period where the correlation coefficient is greater than or equal to 0.9; subsequently, we construct a network linking the two regions. Based on network theory, average path length, clustering coefficient, assortativity, and modularity were derived. As a result, it was found that the temperature network satisfies a small-worldness property and is a network having assortativity and modularity.

• Journal of the Korean Ceramic Society
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• v.35 no.9
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• pp.958-968
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• 1998

Porous silica ceramics were prepared using DCCA(Drying Control Chemical Additives) Such as uncharged polymer(Polyethylene glycol) and protein (Lipase) under H2O/Low-grade TEOS=10 C2H5OH/Low-grade TEOS=1 HC1/Low=grade TEOS=0.01 After Plain which doesn't added DCCA and samples of 11 sorts which varied molecular weight of PEG(Mw=600, 1000, 2000) quantity of Lipase and concentration of wat-er were synthesized gellation time and thermal analysis were investigated. After heat-treated at 600, cry-stal structures analyses of SiO2 polymer and characteristics of pores were investigated. Gellation time was retarded about 2-6 times as compared with plain resulting in addition of DCCA and crystal structures ex-hibited amorphous state. Moreover as increase of water a short gellation time was obtained. The samples added PEG showed increase of specific surface areas up to 20-40% and had micropores while those of Lipase were decreased about 90% and showed broad pore size distribution.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.249-256
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• 2001

The objective of this study was to analyze characters of the vegetation structure, vegetation-environment relationships of Kyeryongsan forest community. Fifty plots were sampled in the valley forest of Donghaksa, Gabsa, Sanghasinri and Shinwonsa regions in Kyeryongsan. Field survey was carried out in August of 1999 to examine a vegetation type and measure a diameter. The classification by TWINSPAN, the DCCA ordination, and structure of stand were used to analyze data. The results of this study are as follows : 1. With the classification by TWINSPAN, the community was categorized into four groups, such as Carpinus laxiflora, Quercus variabilis-Quercus serrata, Zelkova serrata-Celtis jessoensis and Carpinus cordata communities. 2. The dominant species in Carpinus laxiflora community were Carpinus laxiflora, Quercus variabilis, Quercus serrata, Pinus densiflora and Styrax japonica. The dominant species in Quercus variabilis-Quercus serrata community were Quercus variabilis, Quercus serrata, Styrax japonica, Castanea crenata and Platycarya strobilacea. The dominant species in Zelkova serrata-Celtic jessoensis community were Quercus serrata, Castanea crenata, Lindera erythrocarpa, Zelkova serrata and Styrax japonica. The dominant species in Carpinus cordata community were Carpinus cordata, Carpinus laxiflora, Sapium japonicum, Cornus controversa and Zelkova serrata. 3. The results of the correlation between Kyeryongsan valley forest community and environmental factors by DCCA ordination method are as follows; The Carpinus laxiflora community was found in low elevation and steep slope area. The Quercus variabilis-Quercus serrata community was found in low elevation and lower slope area. The Zelkova serrata-Celtis jessoensis community was found in high elevation and lower slope area. The Carpinus cordata community was found in high elevation and midium slope area.

• Journal of the Korean Ceramic Society
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• v.25 no.5
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• pp.479-487
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• 1988

In this study we studied the function of Glycerol as a DCCA(Drying Control Chemical Additives) in the preparation of silica bulk glas through Sol-Gel method. We used TEOS(Tetra Ethyl Ortho Silicate) and maintained the mixing ratio of TEOS : H2O : EtOH : HCI as 1 : 4 : 4 : 0.0007(mol) and varied glycerol input quantity from 0.1vol% considering the ethnaol input quantity as 100vol%. We investigated the changes from Sol-Gel Synthetic solutions to the glass using DT-TG, FT-IR and other instruments. The results obtained from this experiment showed that the dried gels made from the synthetic solutions containing 0.1-1.0vol% of glycerol were easily heat-treated up to 85$0^{\circ}C$ so that transparant bulk silica glass was prepared.

• The Korean Journal of Ecology
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• v.15 no.2
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• pp.117-125
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• 1992

TWINSPAN(two-way indicator species analysis), DCCA(detrended canonical correspondence analysis) and polar ordination method wee used so as to analyze the the relation between forest vegetation and hibitat of mudungsan(1, 187m) located in kwangju area. Vegetationsurvey consulted 1:25, 000 topographical map, set up 41 quadrats and analyzed from April, 1990 to August, 1991. Forest vegetation of mudungsan was classifild to quercus acutissima community, fraxinus mandshurica community, quercus mongolica community, quercus serrata community, quercus dentata community, quercus variabilis community, and pinus densiflora community by TWINSPANmethod, and this almost coincide with the result of plar ordination. according to DCCA analysis, P. densiflora community was formed in xeric and low altitude region which soil nutrient was poor, compared with other communities. q. variabilis and q. acutissima community wee distributed in the region that low altitude and organic matter content was comparatively low, but q. acutissima community was formed in a damp region while q. variabilis community in a xeric region. q. mongolica and f. mandshurica formed the communities in a high altitude region, especially f. mandshurica cmmunity was distributed in a high humidity region. According to polar ordination analysis, the forest vegetation was classified to 7 communities by means of environmental gradient such as humidity, organic matter, ph, temperature, c.e.c and P2O5.