• The Korean Journal of Applied Statistics
• /
• v.29 no.1
• /
• pp.41-59
• /
• 2016

There have been continuous improvements in human life expectancy. Life expectancy is as a key factor in an aging population and can wreak severe damage on the financial integrity of pension providers. Hence, the projection of the accurate future mortality is a critical point to prevent possible losses to pension providers. However, improvements in future mortality would be overestimated by a typical mortality projection method using the Lee-Carter model since it underestimates the mortality index ${\kappa}_t$. This paper suggests a mortality projection based on the projection of the skewness of the mortality versus the typical mortality projection of the Lee-Carter model based on the projection of the mortality index, ${\kappa}_t$. The paper shows how to indirectly estimate future t trend with the skewness of the mortality and compares the results under each estimation method of the mortality index, ${\kappa}_t$. The analysis of the results shows that mortality projection based on the skewness presents less improved mortality at an elderly ages than the original projection.

• Radiation Oncology Journal
• /
• v.16 no.2
• /
• pp.125-138
• /
• 1998

Purpose : To evaluate the late effect(3 and 6 months) of cis-diarnrninedichlo-roplatinum(II)(cisplatin) on the radiation brain damage when the cisplatin was intraperitoneally infused immediately after whole brain irradiation in the rats. Materials and Methods : The histolopathological findings of the brain were examined in rat brains at 3 and 6 months after the treatment. The rats were irradiated(20 or 22.5 Gy, RT) or cisplatin was injected intraperitoneally(2,4, or 8mg/kg, CT) and in combined treatment group, cisplatin(2mg/kg) was injected immediately after irradiation(20 or 22.5 Gr). Histopathological examination was done mostly in irradiation or cisplatin alone groups, because the rats in combined group died during experimental period except 2 rats. Results : The rats treated with cisplatin showed marked epithelial vacuolation with perivascular edema and vascular dilatation in choroid plexus at 3 months as well as multifocal necrosis involving fimbria and cerebellar hemispheres at 3 and 6 months. The changes were more prominent in rats with 2mg/kg injection compared to rats with 8mg/kg injection. The rats with RT and combined CT and RT showed characteristic delayed irradiation effects such as focal coagulation necrosis and vascular changes, which were more marked than previous reports Prominent perivascular and leptomenin-geal astrocytic Proliferation was well documented by anti-GFAP antibody. Cisplatin treatment did not enhance the effect of radiation-induced changes of blood vessels and astrocytic proliferation. Conclusion : The focal necrosis was the most consistently noted finding in this study, it suggested the possibility to use this as an evaluation factor for combined effects of RT and cisplatin.

• Journal of Wetlands Research
• /
• v.16 no.4
• /
• pp.403-411
• /
• 2014

This study Development of Evaluation Items and Indicators for Hydrological Safety on Agricultural Reservoir improvement and grasped the relative importance through stratification of the evaluation points through AHP technique exercised by group of experts. Below conclusion was acquired based on the study done. Firstly, the hierarchy of the evaluation items was divided into two layers: there were six upper evaluation items and eleven lower evaluation items. Secondly, using the analytic hierarchy process, the importance values of the six upper evaluation items were determined via the paired comparison questionnaire survey and consistency check, which were in the order of maintenance condition (condition evaluation grade), freeboard of levee body (non-overtopping), discharge capacity of spillway, potential flood damage, flood calculation factor and freeboard of downstream bank. The maintenance condition(condition evaluation grade) was significantly influenced the results of the hydrological safety on agricultural reservoir evaluation results. Finally, the study indicated that in the short term, improving the safety check condition evaluation grade will be useful to improve the hydrological safety of the agricultural reservoir because it can be performed immediately.

• Journal of the Korean association of regional geographers
• /
• v.19 no.4
• /
• pp.615-626
• /
• 2013

In this study, spatial patterns of the urban flood vulnerability index in Seoul are examined by considering climate exposure, sensitivity, and adaptability associated with floodings for recent 5 year (2006~2010) period by the smallest administrative unit called Dong. According to the results of correlation analyses based on the IPCC(Intergovernmental Panel on Climate Change)'s vulnerability model, among many variables associated with urban flooding, rainwater tank capacity, 1-day maximum precipitation and flood pumping station capacity have statistically-significant, and relatively-high correlations with the number of flood damage in Seoul. The flood vulnerability map demonstrates that the extensive areas along Anyang and Joongnang streams show relatively high flood vulnerability in Seoul due to high sensitivity. Especially in case of Joongnang stream areas, climatic factors also contribute to the increase of flood vulnerability. At local scales, several Dong areas in Gangdong-gu and Songpa-gu also show high flood vulnerability due to low adaptability, while those in Gangnam-gu do due to high sensibility and climate factor such as extreme rainfall events. These results derived from the flood vulnerability map by Dong unit can be utilized as primary data in establishing the adaptation, management and proactive policies for flooding prevention within the urban areas in more detail.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.29 no.4
• /
• pp.299-306
• /
• 2009

Oxidative stress is the main limiting factor in crop productivity. To solve global environmental problems using the plant biotechnology, we have developed on the oxidative stress-tolerant transgenic tall fescue plants via Agrobacterium-mediated genetic transformation method. In order to develop transgenic tall fescue (Festuca arundinacea Schreb.) plants with enhanced tolerance to multiple environmental stresses, nucleotide diphosphate kinase gene under the control of CaMV35S promoter were introduced into genome of tall fescue plants. Proteomic analysis revealed that transgenic tall fescue not only accumulated NDP kinase 2 protein in their cells, but also induced several other antioxindative enzyme-related proteins. When leaf discs of transgenic plants were subjected to cold stress, they showed approximately 30% less damage than wild-type plants. In addition, transgenic tall fescue plants showed normal growth when transgenic plants were subjected to $4^{\circ}C$ for 3 days treatments. These results suggest that transgene is important in ROS scavenging by induction of antioxidative proteins, and could improve abiotic stress tolerance in transgenic tall fescue plants.

• The Journal of Engineering Geology
• /
• v.17 no.3
• /
• pp.411-418
• /
• 2007

It is a very difficult thing to estimate an occurrence possibility location and hazard expectation area by landslide. The prediction difficulty of landslide occurrence has relativity in factor of various geological physical factors and contributions. However, estimation of landslide occurrence possibility and classification of hazard area became available correlation mechanism through analysis of landslide occurrence through landslide data analysis and statistical analysis. This study analyzed a damage possibility of a cultual heritage area due to landslide occurrence by a heavy rainfall. We make a landslide prediction map and tried to analysis of landslide occurrence possibility for the cultural heritage site. The study area chooses a temple of Silsang-Sa Baekjang-Am site and made a landslide prediction map. In landslide prediction map, landslide hazard possibility area expressed by occurrence probability and divided by each of probability degrees. This degree used to evaluate occurrence possibility for existence and nonexistence of landslide in the study site. For the prediction and evaluation of landslide hazard for the cultural heritage site, investigation and analysis technique which is introduced in this study may contribute an efficient management and investigation in the cultural heritage site, Korea.

• Microbiology and Biotechnology Letters
• /
• v.31 no.2
• /
• pp.95-102
• /
• 2003

Microalgae are a diverse group of photosynthetic organisms and abundant in every ecosystem in the biosphere. They are common in aqueous environments including marine, brackish and fresh waters and in some habitats that lack eukaryotic life such as some hot springs and highly alkaline lakes. Microalgal biotechnology that is focused on the microalgae-based production of a variety of useful materials such as pharmaceutical comfounds, health foods, natural pigments, and biofuels is considered as an important discipline with the development of biotechnology. In addition, the mass cultivation of microalgae can also contribute to improving the environmental quality by reducing the concentration of $CO_2$ which is one of major gases lead to global warming. Consequently, it seems that the microalgae can be used as an efficient, renewable, environmentally friendly source of high-value biomaterials such as chemicals, pigments, energy, etc. and the microalgal biotechnology will most likely represent a larger portion of modern biotechnology.

• Journal of Life Science
• /
• v.25 no.5
• /
• pp.539-547
• /
• 2015

This study aimed to investigate the protective effect of Semisulcospira libertina extract on liver injury induced by D-galactosamine in rats. After the administration of S. libertina extract, the local fat degeneration and infiltration of inflammatory cells in liver tissues were significantly decreased and peripheral hemorrhages around portal triads and central necrosis around central veins were found to be protective. The elevated levels of plasma ALT, AST, and LDH, the ALP activation lipid peroxidation, and the lipid contents of a damaged liver were recovered in experimental rats administrated with S. libertina extract, suggesting its role in blood enzyme activation and lipid content restoration within damaged rat liver tissues. Moreover, the expression rate of TNF-α, which accelerates inflammation and induces tissue damage and necrosis, was significantly decreased. In addition, the activities of antioxidant enzymes were more effectively upregulated compared to those of the control group induced hepatotoxicity. All data showed that S. libertina extract has a preventive role against liver damages, such as inflammation and tissue necrosis, as instigated with D-galactosamine by improving the activities of blood enzymes and antioxidant enzymes and modulating the expression of inflammation factor, suggest S. libertina extract is an effective medicinal resource for the restoration of hepatotoxicity.

• KSBB Journal
• /
• v.24 no.3
• /
• pp.312-320
• /
• 2009

Stable cell preservation is an essential factor in the regenerative medicine for cell therapies and transplantation of biologic materials. In this study, we studied to provide more stable hypothermic preservation by protection of cell damage during the preservation at $4^{\circ}C$. The result of searching for key components that have excellent efficacy in hypothermic preservation of cells, we have identified the fact that the hypothermic preservation adding protein hydrolysates such as yeast hydrolysate is far superior to others. All protein hydrolysates that are derived from animal, plant and microbe sources have superior efficacy, especially the peptides which have molecular weights under 10 kDa have the best efficacy among the components of protein hydrolysate. The protein hydrolysates prevented the decrease of ATP level in the cells caused by hypothermic environment and they inhibited the generation of ROS. Adding antioxidants and control agents of osmotic pressure were showed to have more superior efficacy in hypothermic preservation. Finally, KUL261 solution (DMEM/F12 1 : 1 medium, yeastolate 1%, $\alpha$-tocopherol $100{\mu}M$, dextran 2.5%), the preservation solution developed in this study, showed the best efficacy in both cell viability and cell growth more than other conventional preservation solutions. In conclusion, the improved hypothermic preservation solution that contains the protein hydrolysates as a key component provide the best preservation efficacy. It provides better efficacy than other preservation solutions and will contribute to both the development of regenerative medicine and global commercialization in this therapeutic field.

• Journal of the Korean GEO-environmental Society
• /
• v.17 no.12
• /
• pp.35-43
• /
• 2016

With the development of construction technology, constructions of dam and levee (dike) as well as the environmental problems are becoming issues. Recently, many countries have tried to develop and used CSG (Cemented Sand and Gravel), which needs fewer requirements than others in aggregates, constructability and ground condition during the dam construction. Mixing up with small amount of cement, CSG is able to increase the strength and proceed accelerated construction without artificial gradation adjustment of riverbed aggregate and crushed rock on construction site. Thus, CSG can minimize environmental damage resulted from quarries mining and reduce cost of construction. Unlike heat of hydration condition that regular concrete usually met, CSG exposes to repeated dry-wet and freezing and thawing environment. Thus, consider the importance of structure of dam or levee, intensive study on the durability of CSG is needed. In this study, freezing and thawing experiment was carried out to evaluate the durability of CSG. In results, the durability factor of CSG is 30~40 or >40 when the amount of cement is $0.4{\sim}0.6kN/m^3$ or $0.8{\sim}1.0kN/m^3$, respectively. The unconfined compressive strength is reduced to 30~50% or 40~70% when the amount of cement is $0.4{\sim}0.6kN/m^3$ or $0.8{\sim}1.0kN/m^3$, respectively. Taken together, the strength and durability of CSG is reliable when the amount of cement is over $0.8kN/m^3$.