• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.4
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• pp.82-90
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• 2009

It is very important to utilize effectively fibrous waste paper in terms of cost savings, environmental effects, and governmental policies. The quality of final products and runnability of papermaking process are primarily affected by constitutions of fibrous raw materials. In specific, board grade paper depends directly on compositions of waste paper bales. At present, the raw materials of board grade paper are mainly derived from lots kinds of wastepaper. Some papermaking countries, like EU, USA and Japan have advanced classification and management systems of recycled fiber, but Korea has not yet organized systematically. In this study, evaluation of wastepaper bale compositions and their fiber properties were carried out for effective utilization of fibrous raw materials for board grade paper production. 3 kinds of wastepaper bales were classified to fibrous or non-fibrous materials. In case of fibrous materials, KOCC, kraft sack paper and white duplex board matters were main component in total weight basis, and in case of non-fibrous materials, vinyl, plastic and cloth matters were main component, in turns. 3 representative kinds of waste paper were disintegrated and classified, and then prepared to handsheet for evaluation of recycled fiber property. Consequently, fines and ash content of waste paper, isolated from KOCC and white duplex board were higher than that of kraft sack paper. pH values of all kinds of waste fibers were neutral or weak alkaline.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.3
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• pp.20-26
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• 2013

We investigated practical methods of using recycled gypsum board paper in the paper industry. Gypsum board paper is used to produce construction gypsum board, and can be recycled through the recycling process of construction wastes. The experiments were carried out in two ways: One was the substitution of recycled gypsum board papers for KOCC, and the other was the use of recycled gypsum board paper powder. Recycled gypsum board paper was not disintegrated easily, but high temperature and the use of chemicals were able to improve their disintegration. The physical properties of handsheets made of the pulp of recycled gypsum board paper exhibited the same performance level as those made from KOCC except in the parameter of compressive strength. The powder of recycled gypsum board paper was manufactured using a grinder and handsheets were made with the powder and KOCC. The bulk was increased, but the strength properties were decreased by the addition of the powder.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.1 no.1
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• pp.51-61
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• 1995

This paper is discussed on the prospects of packaging industry and technologies of Japan for comming 21th century. It is clear that packaging industry depends on living style and social mechanizms. A trends of numerical consumption, amounts of money and composisition of packaging materials are one of a measure of development of packaging industry. Total consumption of packaging materials in Japan of 1965, 1980 and 1993 were $6,344.5{\times}10^3,\;15,898.7{\times}10^3\;and\;21,603.3{\times}10^3$ tons respectively and also, shipping money of packaging materials were $7,073{\times}10^{11},\;45,421{\times}10^{11}\;and\;63,902{\times}10^{11}$ yen, respectively. It is estimated from these data that the packaging industry is also increasing in future according of GNP of country. Compositions of packaging materials from 1965 to 1993, however, are somewhat changing according to development of new materials or social conditions such as platics packaging or wooden packaging materials. Technical forcasts of packaging industry are shown from view point of national living style, energy and resorces as well as environment of world based on forcasting committee of pulp & paper in Japan, report of research committee for the 21th packaging in JPI and materials of symposium in Kanagawa University in this paper. As a my conclusion, many functional packaging materials shall be developed in the future and accordingly Life Cycle Assesment plays a important role of packaging fields. Furthermore, I am estimating in future the new cellulosic materials such as nonwood fiber resources instead of paper, board, wooden containers and a part of plastic packaging materials shall be developed. This paper is constructed by three items as follow:

• Korean Journal of Materials Research
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• v.26 no.5
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• pp.241-245
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• 2016

Hydrogen is considered a potential future energy source. Among other applications of hydrogen, hydrogen-rich water is emerging as a new health care product in industrial areas. Water electrolysis is typically used to generate a hydrogen rich water system. We annealed 10AA carbon paper in air to use it as an electrode of a hydrogen rich water generator. Driven by annealing, structural changes of the carbon paper were identified by secondary electron microscope analysis. Depending on the various annealing temperatures, changes of the hydrophilic characteristics were demonstrated. The crystal structures of pristine and heat-treated carbon paper were characterized by X-ray diffraction. Improvement of the efficiency of the electrochemical oxygen evolution reaction was measured via linear voltammetry. The optimized annealing temperature of 10AA carbon paper showed the possibility of using this material as an effective hydrogen rich water generator.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.5-21
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• 2015

The common production methods of nanocellulosic (cellulosic nanofibrils, CNF) materials from wood are being reviewed, together with large scale applications and particularly papermaking applications. The high energy demand for producing CNF has been one particular problem, which has been addressed over the years and can now be considered solved. Another problem was the clogging of homogenizers/microfluidizers, and the different routes to decrease the energy demand. The clogging tendency, related to the flocculation tendency of fibres is discussed in some detail. The most common methods to decrease the energy demand are TEMPO-oxidation, carboxymethylation and mechanical/enzymatic pre-treatments in the order of increased energy demand for delamination. The rheology characteristics of CNF materials, i.e. the high shear viscosity, shear thinning and the thixotropic properties are being illuminated. CNF materials are strength adjuvants that enhance the relative bonded area in paper sheets and, hence increase the sheet density and give an increased strength of the paper, particularly for chemical pulps. At the same time papers obtain a lower light scattering, higher hygroexpansion and decreased air permeability, similar to the effects of beating pulps. The negative effects on drainage by CNF materials must be alleviated through the appropriate use of microparticulate drainage aids. The use of CNF in films and coatings is interesting because CNF films and coatings can provide paper/board with good oxygen barrier properties, particularly at low relative humidities. Some other high volume applications such as concrete, oil recovery applications, automotive body applications and plastic packaging are also briefly discussed.

• Journal of Electrochemical Science and Technology
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• v.7 no.2
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• pp.115-131
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• 2016

Though battery chemistry and technology had been developed for over a hundred years back, increase in demand for storage energy, in the computer accessories, cell phones, automobile industries for future battery car and uninterrupted power supply, has made, the development of existing and new battery, as an emerging areas of research. With innovation of high energetic inexpensive Nano structure materials, a more energy efficient battery with lower cost can be competitive with the present primary and rechargeable batteries. Materials electrochemistry of electrode materials, their synthesis and testing have been explained in the present paper to find new high efficient battery materials. The paper discusses fundamental of electrochemistry in finding true cell potential, overvoltages, current, specific energy of various combinations of anode-cathode system. It also describes of finding the performance of new electrode materials by various experiments viz. i. Cyclic Voltammetry ii. Chronoamperometry iii. Potentiodynamic Polarization iv. Electrochemical Impedance Spectroscopy (EIS). Research works of different battery materials scientists are discussed for the development of existing battery materials and new nano materials for high energetic electrodes. Problems and prospects of a few promising future batteries are explained.

• Tribology and Lubricants
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• v.21 no.2
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• pp.77-82
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• 2005

In previous paper, the wear properties of clutch facing materials with two different copper amounts against fly-wheel materials used in the clutch system were investigated by sliding wear tests at different applied loads and speeds. This paper have been aimed to evaluate the friction properties for clutch facing materials at the same test conditions as the previous paper. The experimental results indicated that the friction properties of clutch facing materials are influenced from the thermal conductivities of the clutch facing material and the counter material. The clutch facing material with the lower thermal conductivity and the fly-wheel material with the higher thermal conductivity showed the low and stable friction coefficient in the range of high sliding speed. This appears to be due to the formation of a film on the surface of the fly-wheel material.

• Structural Engineering and Mechanics
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• v.17 no.3_4
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• pp.303-329
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• 2004

Magnetostrictive materials are routinely employed as actuator and sensor elements in a wide variety of noise and vibration control problems. In infrastructural applications, other technologies such as hydraulic actuation, piezoelectric materials and more recently, magnetorheological fluids, are being favored for actuation and sensing purposes. These technologies have reached a degree of technical maturity and in some cases, cost effectiveness, which justify their broad use in infrastructural applications. Advanced civil structures present new challenges in the areas of condition monitoring and repair, reliability, and high-authority actuation which motivate the need to explore new methods and materials recently developed in the areas of materials science and transducer design. This paper provides an overview of a class of materials that because of the large force, displacement, and energy conversion effciency that it can provide is being considered in a growing number of quasistatic and dynamic applications. Since magnetostriction involves a bidirectional energy exchange between magnetic and elastic states, magnetostrictive materials provide mechanisms both for actuation and sensing. This paper provides an overview of materials, methods and applications with the goal to inspire novel solutions based on magnetostrictive materials for the design and control of advanced infrastructural systems.

• Journal of Korea Technology Innovation Society
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• v.8 no.2
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• pp.732-756
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• 2005

This paper attempts to find the sources of materials technology innovation and to analyze the relationships between the sources and materials technology innovation. Starting from the traditional hypothesis on the innovation sources (e.g. technology-push, demand-pull and user-supplier), materials scientific knowledges, materials processing technologies and users' needs are found as three main sources of innovation in materials technology. There are not only close interactions between the sources and materials innovation, but also the interactions among the sources of innovations play important roles for materials technology innovation. This paper discusses the characteristics of interactions between sources of innovation in materials technology. This study on the sources and interactions among sources may provide important information for policymaking in materials technology

• Journal of Korean Home Economics Education Association
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• v.16 no.1
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• pp.19-30
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• 2004

Korean traditional paper is more than paper itself to the Korean people because of its excellence, compared to western paper, in keeping records, flexibility, strength. air permeability. and blocking ultraviolet rays. It has been used for various purposes such as book-making. covering for walls. windows or floors. making clothes and living appliances. and so on. Notwithstanding these merits. mass-produced paper has been substituted for Korean paper. Recently, however, there is a growing tendency to re-evaluate Korean paper because of its physiochemical properties. traditional beauty. eco-friendliness. and applicability to crafts. Korean paper deserves widely received re-evaluation as teaching materials for the education of ecology. creativity. and traditional arts. The purpose of this study was to find out a way of using Korean paper as sewing materials in Practical Arts classes for the elementary school. Previous researches on what properties Korean paper has and how many kinds of crafts have been made of Korean paper were reviewed. Concrete methods of utilizing Korean paper as sewing materials. especially for the finishing skills of sewing. were also proposed.