• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.25-33
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• 1999

A great difference in drainage time was observed from the recycled stocks between corrugated container board and its component papers, liner and medium paper. It could be assumed that the different drainage property should be caused from a starch adhesive present in the corrugated board. Thus, three types of starch such as dried Stein-Hall adhesive, cooked starch solution, and its dried film were added to linerboard stock in order to investigate the mechanism of drainage reduction. The water-swollen starch particles derived from Stein-Hall adhesive were drastically deteriorated the drainage time, even though the amount of starch is very small (2% or below). The drainage time of OCC was improved by 25% when amylase was used a new biological treatment. The results from the lab and mill test showed that the starch-degradable enzymatic treatment improves the drainage property as well as the reduction of calcium hardness.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.251-256
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• 2006

The purpose of this study was to confirm multiple retention system of C-PAM, A-PAM and Inorganic micro particles vs. traditional micro particle system and dual polymer system by measuring retention, drainage and formation using RDA HSF and Techpap 2D -F Sensor The benefits of dual polymer system were easy to use, low chemical consumption and good retention property but defect was worse drainage property than inorganic microparticle systems. On the other hand, Inorganic microparticle system had benefit of good drainage effect but defects were difficult to use, high chemical consumption. Therefore, we tried to find optimal morphology of polyacrylamide and applied to multiple retention system of C-PAM, A-PAM and inorganic microparticles to compensate defects of both of retention systems. As a result, we found the performance of branched C-PAM, branched A-PAM and inorganic micro particle triple system was more appropriate than traditional inorganic mircoparticle systems or dual polymer systems by comparing retention, drainage and formation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.1
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• pp.24-29
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• 2001

The base paper of corrugated board is mainly produced from Korean old corrugated container (KOCC), and thus the recycling rate of KOCC is very high. However, there is a problem that the pulp quality is very low while the recycling rate of OCC is high. The fines content in KOCC, the main source of the corrugated board, amounts to nearly the half of the total stock, and its formation increases as recycling process repeats due to the hornification of fiber. There have been attempts to improve the drainage property of OCC by increasing the headbox concentration of the paper machine or by applying drainage-promoting polymer additives. However, these conventional methods have problems of weakened paper strength and lowered converting fitness caused by paper formation hindrance. The strength of linerboard could not be increased in case KOCC is used, because hornified OCC pulp can-not be sufficiently refined due to the lowered drainage property caused by fines formation. We studied about a new technique consisting of froth-flotation for fractionating pulp stock into a long fiber portion and fines fraction. This study will be developed in order to enhance the drainage and strength properties of a recycled OCC pulp by selective treatment of flocculant on fractionated OCC Fines.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.521-524
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• 2008

In addition the typhoon 'Lusa' of year 2002 has resulted 5,400 billion won of property damage and the damages for roads and railroads were approximated to be 2,860 billion won at 12,377 locations holding 53% damage of total. It was reported that the property damage due to the 2003 typhoon, 'Maemi' was 4,200 billion won. The recent typhoon, 'Aewinia', caused the 1,400 billion-won property damage including sweeping and flooding of 127 roads and 65 rivers, respectively. Therefore, this paper presented to estimate drainage size for debris flow

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.501-522
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• 2013

This study has performed comparative analysis on benefit indicators in agricultural irrigation and drainage project cases between Korea and Japan. The irrigation and drainage project with publicity should do economic analysis of direct benefit factors as well as indirect benefit factors. However, traditional economic evaluations are used that benefit factors are lack of consistency and focused on direct benefits. Therefore, the purpose of this study was to develop indicators for the economic evaluation of irrigation and drainage projects. We conducted a case study between Korea and Japan. The resulting benefit factors was divided into direct factors and indirect factors. The direct benefit factors were increase in income, cost savings. The indirect benefit factors were protection of property due to flooding, agricultural promotion, aesthetic improvement. The implications of this study are that the indicators of economic analysis can be evaluated and easily applied. Moreover, these indicators could promote the feasibility of economic analysis.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.22-28
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• 1998

The blended enzymes were applied for OCC recycling system to use the selective activities of various enzymes. Cellulase and hemicellulase were very effective in terms of the strength of recycled paper The effect of the addition of amylase on the drainage improvement indicates that the starch, which was used as an adhesive of corrugated container, deteriorates the drainage property in OCC recycling system. From the result of Scheffe's analysis, the combination of cellulase and amylase (50/50, w/w) were the most effective in improving the drainage properties with increased strength.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.1
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• pp.3-9
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• 2010

Drainage density, defined as the degree to which a landscape is dissected by streams, is a fundamental property of natural terrain that reflect the comprehensive morphologic response of watershed. In this study the spatial variability of drainage density is analyzed by statistical approach to it and its plotting method is proposed. Overland flow length is confirmed to be a highly variable spatial factor from the result of statistical analysis. Distribution map of drainage density based on spatial autocorrelation length in this study would be a superior tool to the classical definition of drainage density.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.26-32
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• 2000

The impact of major surface chemical properties of silica sols on the retention and drainage performance of the silica based micrparticle system, Compozil was investigated using four different silica sols. And the effect of silica properties on the interactions with cationic starch and cationic plyacrylamide has also been identified. The surface charge density and the stability over pH of silica sols were increased by introducing aluminosilicate anions at surface. It was found that the charge density of silica sols determined the addition level necessary to attain the maximum retention and drainage. When silica sols were combined with cationic starch, the change density of the product was the critical properties and the degree of microagregation was of minor importance. In the cationic polyacrylamide system the degree of colloid structure appeared to be a more critcial property than the charge density of silica sols.

• Korean Journal of Medicinal Crop Science
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• v.15 no.1
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• pp.12-16
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• 2007

This study was carried out to investigate the cultivated soil properties, the growth and yield of Ostericum koreanum Kit. in the Bonghwa area. The results were as follows: In Bonghwa area, soil texture of upland soil were mostly sandy loam and loam. Sloped areas of $7\sim15%$ were plentiful than the other slopes, that of next was $15\sim30%$ slope. Sandy loam and loam soil were mostly 'well' in the drainage class, but loamy coarse sand and loamy sand soil were 'excessively well' drainage class. In the 'moderately well' drainage class, yield of Ostericum koreanum was 289kg/10a, and that of 'poorly' drainage class was low. The yield of loam soil texture was 284kg/10a. Soil organic matter, Potassium and EC were lower in 'poorly' drainage, but the other constituents were not definite tendency by different drainage classes.

• Elastomers and Composites
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• v.39 no.3
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• pp.209-216
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• 2004

Two types of polyurethane-acrylate polymer were synthesized by reaction of 2-hydroxyethyl methacrylate(HEMA), acrylamide(AA), and polyurethane prepolymer. Water-soluble cationic polyurethane/acrylate retention aids were prepared by using polyurethane-acrylate, benzyl chloride and distilled water. The retention, drainage and strength properties of the retention aids were investigated. The retention of cationic polyurethane/acrylate type retention aids maintained around 70 % regardless of nm. COD value of white water was much reduced by adding the retention aids to it. Drainage property was also improved by addition of the retention aids. In addition, specific compression strength of the paper was improved a little by addition of the retention aids. PU-HEMA type showed better performance than PU-AA in terms of compression strength of the paper.