• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.1
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• pp.59-69
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• 2001

Ths paper presents an algorithm of detecting eccentricity signal and diagnosing the cause in rolling process. A designed technique uses only the outputs of load cell and tachorreter, which are generally utilized in rolling process, and need not any acklitional sensors. Detecting signals related to eccentricity is done by combining outputs of 6 digital bandPass filters whose center frequency are varied with roll's rotating frequency. A function of diagnosing the cause of occentricity from extracted data having occentricity components is implemented by defining reasonable variables. In order to show validity of an algorithm designed in this paper, simulation was accomplished for three groups. The first is that some portion of roll in the direction of roll circumference is distorted. The second is that rotating axis and roll center is not identical. The third is that composite cause is occmed Simulation results show that every kind of eccentricity can be diagnosed in terms of algorithm proposed.oposed.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.2
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• pp.149-154
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• 1992

A study was carried out to know the effects of two kinds of paper mill sludge manure compost(SMC) on the growth and chemical components of kidney bean(Phaseolus vulgaris) : Control(SMC-0) contained chemical fertilizer only, sludge manure compost-1(SMC-1) contained 18% of swine manure and 8% of sawdust of the total weight of the manure in addition to the chemical fertilizer, and sludge manure compost-2(SMC-2) contained swine manure without sawdust a third of the total by weight on a fresh weight basis, 1) Kidney bean treated with SMC-1 and SMC-2 showed the increasing tendency of values meristem height, stem diameter, pod number per plot and total grain yield when compared to control(SMC-0) treatment 2) Though there was not a significant difference between SMC-1 and SMC-2 treatments on the growth, SMC-1 tended to increase the value of meristem height, stem diameter, pod number per plot and total grain yield of kidney bean, 3) The contents of aluminium, iron and zinc in kidney bean were higher than other elements, though there was no significant difference between the treatments, And those of chromium, lead and cadmium were negligible. 4) From the results obtained, it can be said that SMC application has more favorable effects on the growth of the plant than control(SMC-0). The effects of SMC-1 application on the growth of kidney bean was more favorable than those of SMC-2.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.219-229
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• 1993

Effects of paper mill sludge-fertilizers were investigated on the growth performances of tree seedlings under field conditions. Two types of sludge-fertilizers applied were an organic sludge compost and a processed sludge-pellet fertilizer strengthened with several components of organic and inorganic nutrients. Three species of tree seedlings studied were ibota privet(Ligustrum obtusifolium) and yellow poplar(Liriodendron tulipifera) of 1-0 year seedlings and also eastern white pine(Pinus strobus) of 2-2 year seedlings. Nitrogen and phosphorus contents of plot soil treated with sludge compost+sludge-pellet fertilizer+sludge-pellet fertilizer plot were increased to 8 times and 2.6 times as those of control plot, respectively. The growth performances of root collar diameter and seedling height were repeatedly measured up to five times through the growing season and the results were analyzed statistically by analysis of variance of randomized block design and Duncan's multiple range test. The growth performances of dry weight were measured after last fifth measurements.

• Journal of the Korea Concrete Institute
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• v.13 no.2
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• pp.114-122
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• 2001

The purpose of this study was to manufacture sintered lightweight aggregate using paper sludge ash and to evaluate the qualities of the aggregate according to various mix proportions, conditions of pelletization and sintering. The paper sludge ash alone, due to its mineral and chemical compositions could not gain suitable expansion and strength. Hence, it was essential to add mineral additives such as clay, fly ash etc. The optimum muting ratio range determined in this study is as follows , paper sludge ash 30∼50 %, clay 30∼50 %, fay ash 0∼40 %, Paper sludge 0∼10% and hematite 2∼3 %(for manufacturing lightweight aggregate both for non-structural and structural concrete). It was possible to manufacture various lightweight aggregate whose dry specific gravity ranged about from 0.6 to 1.4 by using this optimum mixing ratio. From the test results of the qualities of aggregate, it showed that the 10% granules crushing value test and water absorption percentage ranged about 5∼10 ton and 10∼20%. Thus, it was favorably comparable to those of the imported aggregate. The manufactured lightweight aggregate could be used for structural concrete and non-structural concrete.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.24-29
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• 2013

In this study, we investigated the applicability of PCC(precipitated calcium carbonate) as a raw material for the manufacture of duplex-board. Papers were made with white-ledger stock collected from the actual duplex-board mill and PCC in a laboratory, and paper properties including bulk, ash content, tensile strength, burst strength, brightness and opacity were measured. The effect of PCC on the drying energy of duplex-board was also determined by measuring the moisture content of wet web and calculating drying energy reduction. PCC increased bulk and ISO brightness significantly, which means PCC can decrease the use of virgin pulp and recycled fibers. PCC decreased the moisture content of wet web, which means PCC can decrease drying energy consumption. However, paper strength decreased as addition levels of PCC addition increased. Therefore, the addition level of PCC must be determined considering the reduction of paper strengths.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.99-103
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• 2006

Use of recycled fibers in papermaking has been increased for economical and environmental reasons. Recycled panels are major liber resources for brown grades and newsprints. Since the recycled fibers have disadvantageous properties as raw materials for papermaking it is of great importance to optimize the use of these recycled fibers. OCC (Old Corrugated Containers) is the major fiber source for linerboards and corrugating mediums that require diverse specification in strength properties. Many studies have been focused to overcome the problems of strength reduction of brown grades when recycled fibers are used as raw materials. The problem of strength loss for papers made from recycled fibers is closely associated with the increased amount of fines in recycled fibers and hornification of fibers. Fines contained in the recycled fiber resources cause problems not only in paper properties but also in process runnability. This shows that the optimal management and proper use of fines in recycling papermaking system are critical to get most benefits of using recycled fibers. In this study some approaches for optimal use of fiber fines in recycled paper mill have been investigated. Stock samples, prepared in the laboratory and obtained from a recycling plant were used. Fractionation of these samples was made using Sweco screen. And the effect of the addition of polyelectrolytes including cationic PAM and PEI on drainage and retention was evaluated. Different methods of polymer addition were compared to find the most effective ways of treating recycled fiber stocks with polyelectrolytes. Addition of polyelectrolytes to the short fiber fraction was most effective in retention and drainage. The influence of the charge and molecular weight of these two polymers has been examined and discussed.

• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.1-6
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• 2017

More addition of calcium carbonate in printing paper allows savings of the wood fibers and the drying energy. Pre-flocculation of GCC (ground calcium carbonate) using functional polymers was known as the best available technology to make high loaded paper until now, and it allowed less reduction of the paper essential properties such as tensile strength and smoothness at higher GCC content. However, pre-flocculated GCC became unstable in size under the continued agitation in the mill. Therefore, pre-flocculation method was modified in such a way that the in-situ calcium carbonate was formed between the GCC particles of the pre-flocculated GCC, and the resultant became more stable in size, which we named as HCC (hybrid calcium carbonate). HCC turned out to make high tensile strength and smoothness as much as the pre-flocculated GCC and gave much better size stability against stirring. Furthermore, HCC gave high bulk that pre-flocculation could not make.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.324-327
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• 2005

An electrophoretic display using $TiO_2$ particles is the most promising candidate because it offers various advantages such as ink-on-paper appearance, good contrast ratio, wide viewing angle, image stability in the off-state and extremely low power consumption. The core technology of electrophoretic display is the dispersion controlling of $TiO_2$ nano particles in nonaqueous solution. To prepare an ink for electronic paper using electrophoretic properties of $TiO_2$ nano particles, cyclohexane with low dielectric constant and transparency, polyethylene for producing polymer coating layer which reduces apparent gravity of $TiO_2$, and $TiO_2$ powders were mixed together by planetary-mill. The zeta-potential value of $TiO_2$ particles in cyclohexane was measured about -40mV, but was measured over -110mV by dispersant attached to polyethylene-coated $TiO_2$ surface. Prepared electronic ink was filled in cross patterned micro-wall with $200{\mu}m$ in width and $40{\mu}m$ in height on ITO glass designed by photolithography. The response time of electronic paper evaluated by mobility of $TiO_2$ particle between micro-walls was measured 0.067sec, but the drift velocity from reflectance wave form during reverse from of electronic ink was measured 0.07cm/sec.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.106-112
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• 2015

Many researchers have proposed analytical methods to measure the adsorption of di-sulpho fluorescent whitening agents (D-FWAs), but practical methods for D-FWA utilization in an actual paper mill have not been established. In particular, the D-FWA adsorption behavior must be monitored in paper mills to ensure the effective use of D-FWAs. This study used the zeta-potential of pulps as an indicator of the adsorption behavior of a D-FWA. We identified the relationship between the actual adsorption of the D-FWA and the zeta-potential of the pulps as a function of D-FWA addition. zeta-potential measurements were then used to analyze the D-FWA adsorption behavior under different conditions of pulp type, conductivity, and pH. The actual adsorption of a D-FWA was proportional to the ${\Delta}zeta-potential$ of the pulps (i.e., the difference between the zeta-potential of a pulp containing no D-FWA and one containing the D-FWA). The ${\Delta}zeta-potential$ of the pulps was therefore adopted for adsorption analysis. A higher adsorption of the D-FWA was observed onto Hw-BKP than onto Sw-BKP because of the shorter fiber length and higher fines content of Hw-BKP. A high conductivity and an acidic pH decreased the D-FWA adsorption because of direct effects of high ion concentrations and low pH on the D-FWA solubility. Therefore, a D-FWA must be added to Hw-BKP under low conductivity conditions and at neutral or alkaline pH to optimize the D-FWA adsorption.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.77-86
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• 2012

We consider the capacitated lot-sizing and scheduling problem for a paper remanufacturing system that produces several types of corrugated cardboards. The problem is to determine the lot sizes as well as the sequence of lots for the objective of minimizing the sum of setup and inventory holding costs while satisfying the demand and the machine capacity over a given planning horizon. In particular, the paper remanufacturing system has sequence-dependent setup costs that depend on the type of product just completed and on the product to be processed. Also, the setup state at one period can be carried over to the next period. An integer programming model is presented to describe the problem. Due to the complexity of the problem, we modify the existing two-stage heuristics in which an initial solution is obtained and then it is improved using a multi-pass interchange method. To show the performances of the heuristics, computational experiments were done using the real data, and a significant amount of improvement is reported.