• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.3
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• pp.14-22
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• 2016

Pulping is a stage that can change fibrous raw materials into pumpable slurry. Recovered paper can be defibrated to individual fibers by shear stress generated by rotation of a rotor and water. Disintegration of recovered paper is more complicated than that of chemical pulp. When disintegration of recovered paper is poor, screening and cleaning efficiency will be worse and properties of paper will also be deteriorated. Therefore, pulping is an important treatment for improvement of availability of recovered paper and process runnability. In this study, degrees of disintegration of KOCC obtained from a linerboard mill was analyzed with a pilot-scale screen. Flake removal of KOCC slurry was performed by a pilot screen. Simple pumping action gave a positive effect on disintegration of KOCC. After pumping for 10 minutes, paper strength increased without the change of water retention value and fibrillation of KOCC slurry. This phenomena can be explained by modification of hornified surface of KOCC fibers by shear stress generated by pumping. Consequently, disintegration efficiency of KOCC can be enhanced by control of retention time at pulper or an agitation power at chests of papermaking process.

• Journal of the Korean Society of Fashion and Beauty
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• v.5 no.1 s.12
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• pp.71-77
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• 2007

This study attempted to comparative analysis about the physical and morphological damage degrees of hair according to the bleaching methods by $H_2O_2$ concentration. As a result of the changes in the physical characteristics of the hair according to the deceleration operation methods by 3-6-9% and 9% $H_2O_2$ concentration, the intensity of tension considerably decreased but the elongation was increased. And the more the damage of hair, the larger the degree of change. Regarding the method of deceleration operation, the 3-6-9% deceleration operation method was more damaging than the 9% single deceleration operation method. In the change of the characteristics of the form of the hair, the control group of the 5-level deceleration hair generally showed a smooth external appearance and regular and closely overlapped epidermis and undamaged cuticle were observed. But in the 3-6-9% deceleration operation method and 9% single deceleration operation method, damages such as the irregular form of the edge of the epidermis and the unclear boundary between the epidermis occurred.

• Korean Journal of Applied Biomechanics
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• v.21 no.2
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• pp.131-140
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• 2011

The purpose of this study was to evaluate the kinematic characteristics of 5th hurdle clearance during the 100m hurdle final competition at the 2010 Colorful DaeGu pre-championship meeting. This study was also intended to provide the technical data for better performance for preparing the 2011 world championship. Lee and Jung need to change technical movement by reducing the distance of the take-off point from the hurdle and by decreasing the vertical velocity of the C.G.(center of gravity) at the takeoff. Powell's angle of the take-off leg showed bigger at the touchdown and smaller at the takeoff comparing to Lee's and Jung's. Furthermore, Powell's horizontal velocity of the C.G. was maintained at the takeoff and touchdown. So, Lee and Jung need to change angle of the take-off leg the same as Powell's. Both Lee and Jung need to increase the angle of landing leg at the touchdown. In addition to increasing the angle Jung needs to improve the knee and ankle velocity with the hurdling leg.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.12 no.2
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• pp.31-47
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• 2001

From the viewpoint of Information Ethics. I tried to examine the moral justification of Intellectual Property Rights in the age of the digital information society. Lockian traditional argument of property rights which is based on the value of labor and Hegelian theory of personalization, both are not enough to justify the new Intellectual Property Rights. The notions of Intellectual Property Rights are to be changed. One change is from the absolute dominion over material property to the limited dominion over intellectual property. The change from property rights to process control rights is the other. To protect these intellectual property rights, there are three possible protection devices that we might take - legal protection, technical protection and moral protection. I argued that both legal and technical protection have some limitations, so the final way to protect the IP rights is to attempt to establish the moral protection as a fundamental solution.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.2 s.115
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• pp.1-8
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• 2006

In this study a process simulation method was used to analyze the accumulation phenomena of anionic starch in the process white water as the closure level of a fine paper making process is increased. A pilot paper machine was used as a model process. Dynamic simulations of the influence of white water usage ratio and uncoated broke addition ratio on the variation of process variable was monitored as a function of time. Results from the dynamic simulations showed that the volume of reservoirs affected the dynamic behavior of the process. The dynamic behavior of flow rate and dissolved starch concentration in process units were different from each other. The speed of the change of dissolved starch concentration in process units was depend on the starting point of the change of dissolved starch concentration, the length of circulation loop, and the volume of reservoirs.

• Structural Engineering and Mechanics
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• v.50 no.2
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• pp.137-149
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• 2014

In this study, modal parameters such as natural frequencies, mode shapes and damping ratios of RC frames with low strength are determined for different construction stages using ambient vibration test. For this purpose full scaled, one bay and one story RC frames are produced and tested for plane, brick in-filled and brick in-filled with plaster conditions. Measurement time, frequency span and effective mode number are determined by considering similar studies and literature. To obtain experimental dynamic characteristics, Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification techniques are used together. It is shown that the ambient vibration measurements are enough to identify the most significant modes of RC frames. The results indicate that modal parameters change significantly depending on the construction stages. In addition, Infill walls increase stiffness and change the mode shapes of the RC frame. There is a good agreement between mode shapes obtained from brick in-filled and in-filled with plaster conditions. However, some differences are seen in plane frame, like expected. Dynamic characteristics should be verified using finite element analysis. Finally, inconsistency between experimental and analytical dynamic characteristics should be minimize by finite element model updating using some uncertain parameters such as material properties, boundary condition and section properties to reflect the current behavior of the RC frames.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.361-365
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• 1999

This study examined the effects of multiple recycling on deinkability and properties of recycled paper from laser computer printout (LCPO). First, alkaline paper with a 20% printed area was disintegrated by TAPPI standard disintegrator at room temperature. After dewatering, the pulp was flotated and dried in oven at80$^{\circ}C$ for 24 hrs. A sequence of wetting, disintegrating, flotating and drying was one recycling cycle and this cyclic treatment was repeated from zero to five times. The recycled handsheet dropped to 90% of the original brightness after five cycles, and lost the most brightness after five cycles, and lost the most brightness in the first two cycles. However, it had a gain of 10% in opacity after five cycles as the same as the case of nonprinting. And, in this study, the method for determining residual ink(toner) content in recycled handsheets ere established by means of SEM-EDX and Py-GC. The change of residual ink percentage on recycled paper showed the effect of recycling numbers on deinkability of waste paper. A slight decrease in deinkability was noted for the recycled handsheets, which may be due to the change of fiber surface free energy connected with fiber swelling.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.499-504
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• 2006

To improve the quality of coating paper, many areas, such as the manufacturing process of inorganic pigment for the coating, the property change of coating color, the surface design of coating pigment and the productivity of coated paper, were studied. In this study the physical properties and printability of coated paper were compared with the coating pigment to modify the surface of large particle and the coating pigment to mix together the large and small particles. After the coating color was mixed under the same conditions in order that the coating color has the same printability, the printability change caused by the surface modification of coating color was investigated. With the surface SEM of coated paper, the efficiency of the surface modification of coating pigment was investigated. The physical property and printability of coated paper, in addition to the physical properties of coating color, were compared and evaluated. Also, the efficiency of printability was evaluated, changing the mixing condition.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.1
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• pp.43-51
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• 2012

Carbon dioxide emission trading market would play very important role in the global effort to cope with climate change. In KOREA, the energy consumption and geen house gas emission of various industry would be controlled by the low carbon-green growth law which was established at 2009. The paper industry as one of major industries in terms of energy consumption has been greatly required to prepare action plan for addressing this regulation and reduction of carbon dioxide emission. In this study, the current states of carbon dioxide emission trading market were analyzed in terms of practical responses of the paper industry. And the various action plans including CDM projects for paper industry were suggested.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.4
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• pp.42-51
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• 2013

Climate changes have become the major issue for the sustainable society and the various regulation has been established for promoting low carbon and green growth in Korea. The paper industry as a large comsumer of energy is forced to cope with these regulation. In this study, the various examples were investigated for providing the basic schemes to develop environmental management strategies of Korean paper industry. The various cases to follow carbon economic were introduced and were categorized into five ways, for example, the carbon capture projects such as reforestation, the increasing the process efficiency, the resource recovery form process waste, the cogeneration systems, the application of non-woody biomass.