• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.598-601
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• 2006

The Purpose of this study is to develope the method for early recovery of the biodiversity in the oligotrophical costal area, it is important in the recovery of the biodiversity to make kelp forest grow in the concerned area. In order for it, sufficient nutrient is required as well as the proper seedbed, Hence in this study, granulated fertilizer, which contains nutrient, such as nitrogen, phosphorus and etc, is coated by cement paste, and then is mixed in to the porous concrete in order to provide seedbed and nutrient simultaneously. As a result of examination of growth property of marine plants of multiple performance concrete for kelp forest regeneration, seaweeds is adhered plentifully when the number of days is longer. when the granular fertilizer mixed. adherence and growth of marine plants is excellent and is stabilized over the long run. In case 6 month of the number of days immersed, marine plants and growth will appear.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.15-23
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• 1991

The early vegetational recovery and species diversity were investigaed in burned pine forest of Mt. Todoksn from 1986 to 1990. The changes of vegetation in the burned site occurred Miscanthus→Miscanthus-Lespedeza→Lespedeza community. The biological spectra based on SD(%) and SP(%) of the burned site were similar to the unburned site with H---e type. The degree of succession(DS) was gradually increased with succession in burned site. The species diversity index(H') and evenness index(e) were declining successional trend, nut dominance index(C) inclining successional trend in the burned site. The domiance-diversity curves of the burned site showed gradual decrease in diversity and evenness, and then slopes of them were progressively steep in early successional stage.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.521-524
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• 2004

The Purpose of this study is to develope the method for early recovery of the biodiversity in the oligotrophical costal area, it is important in the recovery of the biodiversity to make kelp forest grow in the concerned area. In order for it, sufficient nutrient is required as well as the proper seedbed, Hence in this study, granulated fertilizer, which contains nutrient, such as nitrogen, phosphorus and etc, is coated by cement paste, and then is mixed in to the porous concrete in order to provide seedbed and nutrient simultaneously. The physical and mechanical properties, such as water permeability, void ratio, compressive strength of porous concrete with granulated fertilizer are discussed.

• Journal of the Korean Wood Science and Technology
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• v.40 no.2
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• pp.78-90
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• 2012

Soybean hull is an attractive feedstock for glucose production. To increase the glucose conversion in acid hydrolysis, a pretreatment method combined steam explosion with alkali pretreatment for soybean hull was studied. For first step pretreatment, steam explosion conditions (log Ro 2.45) were optimized to obtain maximum solid recovery and cellulose content. In the second step pretreatment, the conditions for potassium hydroxide pretreatment of steam exploded soybean hull were optimized by using RSM (response surface methodology). The optimum conditions for minimum lignin content were determined to be 0.6% potassium hydroxide concentration, $70^{\circ}C$ reaction temperature and 198 min reaction time. The predicted lignin content was 2.2% at the optimum conditions. Experimental verification of the optimum conditions gave the lignin content in similar value with the estimated value of the model. Finally, glucose conversion of pretreated soybean hull using acid hydrolysis resulted in $97.1{\pm}0.4%$. This research of two-step pretreatment was a promising method for increasing the glucose conversion in the cellulose-to-glucose process.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.1
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• pp.65-73
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• 2011

The fibrous raw materials in packaging-grade paper production in Korea were mainly obtained from waste paper. The use of recycled paper has both positive and negative impacts in papermaking process. The primary positive impacts are the environmental protection and manufacturing cost reduction, and the negative impacts are the quality reduction in paper quality and the accumulation of heavy metals and other pollutants in wet- and dry-end process. This study was carried out to consider the optimum acid decomposition system with the highest recovery rate for the analysis of heavy metals in packaging-grade paper. The open digestion system using Kjeldahl apparatus and the closed digestion system using microwave oven for decomposing the organic materials in paper were compared. In both open and closed digestion method, the combination of nitric acid, hydrochloric acid and hydrogen peroxide showed higher recovery rate than using only nitric acid alone because the presence of Cl- ions in hydrochloric acid stabilizes ligand formation with metal ions. KOCC was observed to have the highest heavy metal content among the recycled paper samples. The heavy metal contents decomposed with the closed digestion system were relatively higher than with open digestion system.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.578-590
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• 2015

The present study examines the influence of slurry composting and biofiltration liquid fertilizer (SCBLF) treatment on the biomass characteristics of yellow poplar, and the optimization of organosolv pretreatment for sugar production. After SCBLF treatment, total exchangeable cation contents of yellow poplar was increased from $3.1g\;kg^{-1}$ to $4.4g\;kg^{-1}$, and as a result, biomass production of yellow poplar was also enhanced by 82.3%. Organosolv pretreatment was conducted with three independent variables: 1) reaction temperature: $133.2^{\circ}C$ to $166.8^{\circ}C$; 2) acid concentration: 0.2% to 1.8%; and 3) reaction time: 1.6 min to 18.4 min. Reaction temperature was the most significant variable in water insoluble solid (WIS) recovery rate. High overall sugar yield was attained from pretreatment conditions approximately 50% of WIS recovery rate, and the highest overall glucose yield (44.0%) was achieved from pretreatment at $140^{\circ}C$ with 1.5% acid concentration for 5 min. Consequently, 21.1% of glucose and 5.8% of xylose were produced from the organosolv pretreatment of SCBLF-treated 8-year-old yellow poplar.

• Journal of the Society of Disaster Information
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• v.9 no.3
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• pp.347-357
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• 2013

Abstract The objective of this study is to investigate and analyze understanding of residents living in landslide disaster impact areas to landslide mitigation and recovery projects with respect to develop socio-economic damage level standards of landslide disasters. South Korea is one of the representative mountain-side urbanized countries that cities have been developed through mountain-side urbanization due to high population density because mountain areas occupy 64 percent of the total land proportion. South Korea were recently suffered from the massive landslide disasters with significant causality that overcomes the annual drowned causality of flood disasters. Consequently, the total death toll of South Korea landslide disasters including unexpected Mt. Woo-Myun disaster and Chuncheon disaster in 2011 became forty-three persons. The hugh amount of disaster management budget was spent in landslide mitigation and recovery projects of the affected areas. This research performed facility field research and resident surveys for landslide damage conditions and damage factors for Mt. Woo-Myun, Chuncheon, Pusan, and Dongdoochon that were major effect cities of 2011 landslide disasters.

• Journal of Forest and Environmental Science
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• v.36 no.2
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• pp.69-77
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• 2020

Lignocellulosic biomass has recalcitrant characteristics against chemical and biological conversion due to its structural heterogeneity and complexity. The pretreatment process to overcome these recalcitrant properties is essential, especially for the biochemical conversion of lignocellulosic biomass. In recent years, pretreatment methods using ionic liquids (ILs) and deep eutectic solvents (DESs) as the green solvent has attracted great attention because of their advantages such as easy recovery, chemical stability, temperature stability, nonflammability, low vapor pressure, and wide liquids range. However, there are some limitations such as high viscosity, poor economical feasibility, etc. to be solved for practical use. This paper reviewed the research activities on the pretreatment effect of various ILs including DESs and their co-solvents with organic solvents on the enzymatic saccharification efficiency of lignocellulosic biomass and the nanocellulose preparation from the pretreated products.

• The Journal of Fisheries Business Administration
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• v.42 no.1
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• pp.37-55
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• 2011

This study is to examine the economic effects of seaweed forest creation project in the case of Jeju Woodo Seokwang－ri. Seaweed forest creation project will raise up the quality and quantity of coastal fisheries resource and improve the structure of coastal ecosystem as a project the recovery of coastal fisheries resource against barren ground like whitening event. The economic effect by seaweed forest creation project can be found not only in the income increase of fishermen but also in reduction of carbon dioxide. The results of this study are summarized as follows: First, the income increase effect of fishermen has economic value of 26,945 thousand won under a 30-year cash flow based on a 8.5% discount rate. This suggests that the seaweed forest creation project increases income of fishermen. Second, the reduction effect of carbon dioxide has economic value of 1,083 thousand won per year. This indicates that the seaweed forest creation project reduces carbon dioxide. In conclusion, the results of this study suggest the seaweed forest creation project has economic value in the case of Jeju Woodo Seokwang-ri.

• Korean Journal of Environment and Ecology
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• v.36 no.5
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• pp.525-534
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• 2022

In this study, we investigated the psychological and physiological effects of experiences in real natural forests and virtual forests using artificially controllable VR. The experiment tested 60 adult college students in a natural forest and a graduate seminar room where external light was blocked. It evaluated the effects of the natural and the VR forest environments by comparing the psychological and physiological recovery of the subjects. Psychometric testing using the PANAS psychological index showed increased positive emotions and decreased negative emotions after experiencing forest scenery in the natural and VR forest environments. And a stress index, based on measuring cortisol in saliva, decreased significantly in the subjects in both environments. The experiment results can be used to support the creation of a psychological and physiological recovery environment with VR for those who cannot go to the natural forest due to certain restrictions such as physical distance, mobility difficulties, etc. It is expected that the results will be the basis for further research into the visual effects of forest healing and also for widening the use of VR, a technology of the fourth industry, in the field of forestry.