• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.3
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• pp.79-85
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• 2012

In this study, purified cellulose was prepared from rice husk which is one of the major agricultural residues in Korea. The various bleaching processes such as ozone bleaching, $ClO_2$ bleaching and $H_2O_2$ bleaching were applied to remove residual lignin and impurities. In order to increase the contents of ${\alpha}$-cellulose contents, the effects of acid and alkali treatments were evaluated. Although the multi stages of the bleaching processes resulted in less than 0.5 % residual lignin contents, the application of ozone leaded to the decrease in DP(degree in Polymerization) and ${\alpha}$-cellulose contents. The alkali treatment after bleaching processes resulted in pure cellulose which showed more than 98% of ${\alpha}$-cellulose contents.

• IE interfaces
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• v.13 no.1
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• pp.54-59
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• 2000

Presented in this paper is a development of knowledge management system based on knowledge life cycle. Knowledge processes in an organization have a life cycle from creation to disposal. So, KMSs have to support the entire life cycle of knowledge. This paper proposes desired knowledge life cycle model, and extracted functional requirements for KMS. For the fulfillment of this requirements, we developed KMS called XM-Brenic/MSX. This system has 6 components for supporting the knowledge life cycle.

• Journal of Korean Elementary Science Education
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• v.25 no.4
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• pp.339-351
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• 2006

The purpose of this study was to analyze the processes of observation teaching and the types of observation in elementary life science class. For the purposes of this study, 40 teachers majoring in elementary science education participated in surveys on the processes of observation teaching. In addition, after videotaping the observation classes conducted by three teachers, each teaching in the 3rd to 5th grade, and their one hundred and eight students, we analyzed the processes of observation teaching. As a result, the processes of observation leaching in elementary science class were categorized into 12 stages (motivation, stating the objective, recognizing objects to observe, free and subjective observation, introducing ways to observe, observing by the simple way, introducing additional ways, observing by the manipulative way, making a note of observation, looking over the contents of observation, finding regularities, consolidation). In the types of observation, teachers and students performed mostly simple observing by the visual way. Teachers introduced time-independent/non-compared/whole observing; students concentrated on time-independent/non-compared/particular observing as targets. Thus, students carried out observing in the types of observation that teachers had presented. Consequently, the analysis about the processes of observation teaching can establish an effective teaching program for observing in scientific activities by reconstructing its observing target and suitable topic. The analysis about the types of observation can be applied to set up strategies for improving observation skills.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.976-979
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• 2000

This paper describes a Life Cycle Engineering approach which is able to optimize a product under technical, ecological and economical requirements. The methodology of Life Cycle Engineering comes with a holistic approach for the analysis of processes, products, systems or services. The Life Cycle Engineering approach is combining environmental and economical parameters and using the technical requirements for setting the baseline for the studies. This paper also describes the approach method for ？ㄴ composed in large numbers sub-parts.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.203-203
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• 2005

• BMB Reports
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• v.53 no.5
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• pp.241-247
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• 2020

As an intracellular degradation system, autophagy is an essential and defensive cellular program required for cell survival and cellular metabolic homeostasis in response to various stresses, such as nutrient deprivation and the accumulation of damaged organelles. In general, autophagy flux consists of four steps: (1) initiation (formation of phagophore), (2) maturation and completion of autophagosome, (3) fusion of autophagosomes with lysosomes (formation of autolysosome), and (4) degradation of intravesicular components within autolysosomes. The number of genes and reagents that modulate autophagy is increasing. Investigation of their effect on autophagy flux is critical to understanding the roles of autophagy in many physiological and pathological processes. In this review, we summarize and discuss ways to analyze autophagy flux quantitatively and qualitatively with the use of imaging tools. The suggested imaging method can help estimate whether each modulator is an inhibitor or a promoter of autophagy and elucidate the mode of action of specific genes and reagents on autophagy processes.

• BMB Reports
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• v.51 no.6
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• pp.274-279
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• 2018

Mitochondria are crucial organelles that generate cellular energy and metabolites. Recent studies indicate that mitochondria also regulate immunity. In this review, we discuss key roles of mitochondria in immunity against pathogen infection and underlying mechanisms, focusing on discoveries using Caenorhabditis elegans. Various mitochondrial processes, including mitochondrial surveillance mechanisms, mitochondrial unfolded protein response ($UPR^{mt}$), mitophagy, and reactive oxygen species (ROS) production, contribute to immune responses and resistance of C. elegans against pathogens. Biological processes of C. elegans are usually conserved across phyla. Thus, understanding the mechanisms of mitochondria-mediated defense responses in C. elegans may provide insights into similar mechanisms in complex organisms, including mammals.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1731-1738
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• 2014

The life of a mother undergoes a dramatic change after a child is diagnosed with cancer. The present study aimed to determine effects on the everyday life process and health status of mothers with children suffering from leukemia. This qualitative study was based on a grounded theory approach with sixteen mothers. The results indicate that after onset of disease in their children, they marginalized their own health and tied their identities to taking care of the child and keeping the child healthy by ignoring themselves, becoming imprisoned in a taking-care-of-the-child position, and trying very hard for seek balance and stability Enduring physical pressures on the one hand, and constantly attempting to achieve balance and stability in family processes on the other hand, gradually cause exhaustion. It seems that health care providers and nurses should pay much more attention to the health status of this group of mothers.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.1
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• pp.61-67
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• 2000

Gears are the most commonly used parts in automotive and industrial applications. One of most common modes of gear failures is tooth breakage, which is usually produced by the bending fatigue failure. It is important to manufacture the gears which can withstand the applied stresses in view of safety and economic requirement. This paper deals with bending fatigue strength for cold forged bevel gear. Especially, to compare fatigue characteristics for manufacturing processes difference, bending fatigue tests of bevel gears made by three different processes respectively. Results indicate that the fatigue strength of bevel gear is improved by cold forging process. Intergranular fracture is found on fatigue fracture surface, and dimples are observed on final fracture surface. The fatigue failure cannot be considered as a deterministic quantity, but must be characterized statistically. This study proposes a method to estimate bending fatigue lift of the bevel gear using the probability-load-life and Weibull analysis.

• Molecules and Cells
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• v.40 no.2
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• pp.90-99
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• 2017

Caenorhabditis elegans is an important model organism with many useful features, including rapid development and aging, easy cultivation, and genetic tractability. Survival assays using C. elegans are powerful methods for studying physiological processes. In this review, we describe diverse types of C. elegans survival assays and discuss the aims, uses, and advantages of specific assays. C. elegans survival assays have played key roles in identifying novel genetic factors that regulate many aspects of animal physiology, such as aging and lifespan, stress response, and immunity against pathogens. Because many genetic factors discovered using C. elegans are evolutionarily conserved, survival assays can provide insights into mechanisms underlying physiological processes in mammals, including humans.