• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.3
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• pp.211-221
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• 2016

Waste salt generated from a pyro-processing for the recovery of uranium and transuranic elements has high volatility at vitrification temperature and low compatibility in conventional waste glasses. For this reason, KAERI (Korea Atomic Energy Research Institute) suggested a new method to de-chlorinate waste salt by using an inorganic composite named SAP ($SiO_2-Al_2O_3-P_2O_5$). In this study, the de-chlorination behavior of waste salt and the microstructure of consolidated form were examined by adding $B_2O_3$ and $Fe_2O_3$ to the original SAP composition. De-chlorination behavior of metal chloride waste was slightly changed with given compositions, compared with that of original SAP. In the consolidated forms, the phase separation between Si-rich phase and P-rich phase decreases with the amount of $Al_2O_3$ or $B_2O_3$ as a connecting agent between Si and P-rich phase. The results of PCT (Product Consistency Test) indicated that the leach-resistance of consolidated forms out of reference composition was lowered, even though the leach-resistance was higher than that of EA (Environmental Assessment) glass. From these results, it could be inferred that the change in the content of Al or B in U-SAP affected the microstructure and leach-resistance of consolidated form. Further studies related with correlation between composition and characteristics of wasteform are required for a better understanding.

• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.726-735
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• 2010

Publications with the data on allometric equation, biomass and productivity of major oak forests in Korea were reviewed. Different allometric equations of major oak species showed site- or speciesspecific dependences. The biomass of major oak forests varied with age, dominant species, and location. Aboveground tree biomass over the different oak species was expressed as a power equation of the stand age. The proportion of tree component (stem, branch and leaf) to total aboveground biomass differed among oak species, however, biomass ranked stem > branch > leaf in general. The leaf biomass allocation over the different oak species was expressed as a power equation of total aboveground biomass while there were no significant patterns of biomass allocation from stem and branch to the aboveground biomass. Tree root biomass continuously increased with the aboveground biomass for the major oak forests. The relationship between the root to shoot ratio and the aboveground tree biomass was expressed by a logarithmic equation for major oak forests in Korea. Thirteen sets of data were used for estimating the net primary production (NPP) and net ecosystem production (NEP) of oak forests. The mean NPP and NEP across different oak forests was 10.2 and 1.9 Mg C $ha^{-1}year^{-1}$. The results in biomass allocation, NPP and NEP generally make Korean oak forests an important carbon sinks.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.4
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• pp.43-56
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• 2014

In this study, ecological investigation was performed on Yong-neup, Daeam-san for 5 times. This area is considered DMZ zone located between Yanggu-gun and Inje-gun, Gangwon-do, where has been recognized highly valuable for ecological preservation. As a result, Sphagnum and hydrophobic vegetation were found in Little Yong-neup, revealing its characteristics of high moor, where as no Sphagnum were found in Baby Yong-neup. Thereby, the carnification has been investigated in both Little Yong-neup and Baby Yong-neup. A main cause of damage was associated with the creation of stating rink and increases of visitors. The damages of vegetation in Little Yong-neup and Baby Yong-neup have been intensified by road construction or uses of groundwater while relocating military troops to upper stream of Little Yong-neup and Baby Yong-neup, further causing the damages of water circulation system and soil erosion. These artificial factors have caused the carnification of wetland protection areas including Little Yong-neup. The terrestrial vegetations, such as Plantago asiatica, Geranium Koreanum and Artemisia feddei have increased compared to current survey conducted by the Ministry of Environment. 5 endangered species, such as Lychnis wilfordii and Trientalis europaea and 5 other introduced species, such as Aster pilosus and Taraxacum officinale were found. 10 different species of mammal and 2 species of amphibian were investigated; and in addition to this, a original form of Sphagnum fens, the remaining wetland was found. Therefore, this study is to identify the causes of damages in Little Yong-neup and Baby Yong-neup through their ecological survey and accordingly proposing a direction for ecological restoration through the improvement of water circulation system, creation of habitats for plant and animal, restoration of vegetation through eco-friendly materials and indigeneity, relocation of the current military troops, securing of structural stability.

• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.1-10
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• 2003

The purpose of this study is to evaluate the capacities of repaired structural walls with different shear span ratios(1, 2, 3). Experimental tests were carried out. In this study three isolated large-scale wall specimens were made. The original wall specimens were tested until the drift reaches more than 3%. The region of the damaged specimen with the crack larger than 0.2 mm is replaced by new concrete. Also, severly distorted reinforcements were also replaced by new reinforcements. The crack smaller than 0.2 mm was cured by epoxy resin. Because of the space limitation of the laboratory the dimensions of all walls are the same. The shear-span ratio was controlled by the combination of axial and lateral force using the special test setting. All specimens were tested using the incremental quasi static cyclic load until failure occurs. Test results show that strength of repaired walls was almost equivalent to that of original walls. However, deformation capacities of repaired wall specimens are inferior to the original wall specimens.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.123-130
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• 2020

These experiments were to investigate the variations of rye on forage quality, productivity and β-carotene concentration affected by maturity in Pyeongchang region. Limited information are available about how forage quality and β-carotene content are affected by various factors. Samples were collected from rye harvested every 5 days, from April 25 to May 31 (April 25, April 30, May 4, May 9, May 15, May 21, May 25 and May 31). Dry matter (DM) content, plant height, DM yield and total digestible nutrient (TDN) yield increased continuously with the progressed maturity. However, crude protein (CP) content, in vitro dry matter digestibility (IVDMD) and relative feed value (RFV) decreased markedly with the delay of harvesting, while TDN content decreased from April 25 till May 15, then followed by a stable fluctuation. Conversely, acid detergent fiber (ADF) and neutral detergent fiber (NDF) value increased and then fluctuated slightly after blooming stage. For quality of plant parts, stem contained the lowest CP content and RFV value, and the highest ADF and NDF contents compared with other parts, while the grain showed the higher CP, IVDMD, RFV and lower fiber contents than others. With the plant matured, leaf proportion decreased while stem and grain proportion increased, and feed value of all the three parts decreased till blooming stage and followed by a stable phase. β-carotene concentration showed its highest on jointing stage, and then fell down sharply on the sequential stages. In conclusion, harvest around May 15 (blooming) is proper for forage rye if directly consumed by livestock as green chop in Pyeongchang under the consideration of both nutritive yield and forage quality.

• Toxicological Research
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• v.14 no.3
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• pp.453-457
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• 1998

In order to evaluate the mutagenic potential of Intralipidos produced by Greenmate cooperation. We performed Salmonella typhimurium reversion assay, chromosomal aberration test on chinese hamster ovarian cells and in vivo micronucleus assay using mouse bone marrow cells. In the reverse mutation test using Salmonella typhimurium TA98 and TA100, Intralipidos did not increase the number of revertant at any of the concentration tested in this study. Intralipidos did not increase the number of cells having structural or numberical chromosome aberration in cytogenetic test. In mouse micronucleus test, no significant increase were observed in the occurrence of micornucleated polychromatic erythrocytes in ICR male mice intraperitoneally administered with Intralipidos. These results indicate that Intralipidos has no genetic toxicity under these experimental conditions.

• Journal of Korean Medical classics
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• v.25 no.2
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• pp.25-41
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• 2012

Objective : Neijingshiyifanglun with additions and emendations was written by Liu Yude, a doctor who lived during Ming period. I researched the origin of the book, and analyzed the features of it as well. I also approximated his birth date and death date. In doing this, I gained a better understanding the practice of medicine in ancient China. Method : I researched the book by comparing its contents, including the causes of diseases, the descriptions of symptoms, the transmissions of diseases, and treatments, with other sources that he had referenced. Result : In understanding Hwangdineijing, Liu Yude was influenced by many medical scholars such as, Wang Bing, Ma Shi, and Wu Kun, but his opinion is most similar to that of Zhang Jiebin. In the field of the Chinese Medical Theory, he was deeply influenced by 'JinYuan-Sidaijia's theories, particularly Li Gao and Zhu Zhenheng. In fanglun, he was greatly influenced by Yifangkao. He concluded that 'aggregationaccumulation' was a disease of stuffiness, and suggested its cure in through 'yangjingzezichu' and 'treatment of blood aspect'. He recognized the disease of 'reversal of qi' as the disease of 'jiaoqi'. He also indicated that the word of 'qi' is not 'rough' but 'tears' or 'yingfengliulei'. Conclusion : 1. He was an excellent medical practitioner and scholar in the history of oriental medicine. 2. He found and corrected errors in the opinions of Wang Bing, Ma Shi, and Wu Kun. 3. He frequently practiced Taipinghuiminhejijufang, and considered Spleen-Stomach, yin-blood, and fire-heat important. 4. He captured the spirit of Huangdisuwenxuanminglunfang, Neijingshiyifanglun, Yifangkao in views of remedy and theory. 5. Neijingshiyifanglun with additions and emendations is the most comprehensive book about fanglun because of its thorough analysis of the Hwangdineijing and its connection to the treatment of ancient diseases in Oriental Medical History.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.169-169
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• 2011

Xylans are polysaccharides present in large amounts in cell walls of land plants. However, during kraft cooking, a high portion of hemicelluloses including xylans are dissolved in the cooking liquor. In the current trend for a more effective utilization of biomass, attention has been paid to the exploitation of xylans as strength-enhancing additives for paper. It is believed that surface xylan adds flexibility to the cell wall/fiber surface, resulting in stronger fiber-fiber joints or greater contact area between the fibers. Accordingly, there is proposal for a new pulping process involving the extraction of xylan prior to pulping, followed by their re-adsorption on the unbleached pulp. A suitable bleaching process should be employed then, which ought to does not only improve the brightness of the pulp, but also remain the effect of the adsorption of xylan on pulp fibers. The objective of this research was to investigate the impact of hydrogen peroxide bleaching on the properties of unbleached hardwood kraft pulp pretreated with birchwood xylan by measuring optical properties (brightness, post color number, opacity) as well as physical properties (tensile index, tearing index, bulk) of handsheets made from the bleached pulp. In the meantime, the influence of process variables of peroxide bleaching including bleaching temperature, time, initial pH and $MgSO_4$ dosage were studied.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.5
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• pp.16-23
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• 2010

This paper presents 6bit 250MS/s flash A/D converter which can be applied to wireless communication system. To solve the problem of large power consumption in flash A/D converter, control algorithm by input signal level is used in comparator stage. Also, input voltage range detector circuit is used in reference resistor array to minimize the dynamic power consumption in the comparator. Compared with the conventional A/D converter, the proposed A/D converter shows 4.3% increase of power consumption in analog and a seventh power consumption in digital, which leads to a half of power consumption in total. The A/D converter is implemented in a $0.18{\mu}m$ CMOS 1-poly 6-metal technology. The measured results show 106mW power dissipation with 1.8V supply voltage. It shows 4.1bit ENOB at sampling frequency 250MHz and 30.27MHz input frequency.

• Journal of Ecology and Environment
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• v.35 no.3
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• pp.243-249
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• 2012

Biomass expansion factors, which convert timber volume (or dry weight) to biomass, are used for estimating the forest biomass and accounting for the carbon budget at a regional or national scale. We estimated the biomass conversion and expansion factors (BCEF), biomass expansion factors (BEF), root to shoot ratio (R), and ecosystem biomass expansion factor (EBEF) for Quercus mongolica Fisch. and Quercus variabilis Bl. forests based on publications in Korea. The mean BCEF, BEF, and R for Q. mongolica was 1.0383 Mg/$m^3$ (N = 27; standard deviation [SD], 0.5515), 1.3572 (N = 27; SD, 0.1355), and 0.2017 (N = 32; SD, 0.0447), respectively. The mean BCEF, BEF, and R for Q. variabilis was 0.7164 Mg/$m^3$ (N = 17; SD, 0.3232), 1.2464 (N = 17; SD, 0.0823), and 0.1660 (N = 8; SD, 0.0632), respectively. The mean EBEF, as a simple method for estimating the ground vegetation biomass, was 1.0216 (N = 7; SD, 0.0232) for Q. mongolica forest ecosystems, and 1.0496 (N = 8; SD, 0.0725) for Q. variabilis forest ecosystems. The biomass expansion factor values in this study may be better estimates of forest biomass in Q. mongolica or Q. variabilis forests of Korea compared with the default values given by the Intergovernmental Panel on Climate Change (IPCC).