• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2021.04a
• /
• pp.35-35
• /
• 2021

This study was conducted to improve and supplement the system of cryopreservation for adventitious bulbs induced by tissue cultured bulb-scales of lily (Lilium spp.) cvs. 'MilkyWay'. The explants, bulblets and bulb-scale-bulblets, were treated to low temperature (4℃) for 7 days prior to the pre-culture. The adventitious bulbs were pre-cultured in Murashige and Skoog (MS) liquid medium supplemented with sucrose (0.3 and 0.7M). The pre-cultured adventitious bulbs were treated to loading solution (LS1 or LS2, C4 or C6) containing 35% of PVS3 (LS1, C4) or 40% of PVS3 (LS2, C6) for 40 min and exposed to dehydration solution (PVS3, B1) containing 50% glycerol and 50% sucrose for 60 min at 25℃. The adventitious bulbs were moved onto droplets containing 3 ㎕ PVS3 on sterilized aluminum foils, and then soaked into liquid nitrogen (LN) for 60 min. The result of highest regrowth rate as 65.7% was obtained in cold treatment (4℃), osmoprotected with LS1 solution, and cultured in PCM3 medium by using bulb-scale-bulblet for cryopreservation. This result shows that droplet-vitrification could be used as a promising method for long-term storage of lily genetic resource.

• International Journal of Highway Engineering
• /
• v.14 no.5
• /
• pp.11-19
• /
• 2012

PURPOSES: The new methodology is proposed for estimation of long-term performance and pavement life based on the national highway database in Daejeon area. Furthermore, this study tried to verify the applicability of performance estimation using NHPCI (National Highway Pavement Condition Index) on tendency of pavement deterioration as time goes by under Korean road environments. METHODS: Reliability theories are applied to estimate the mean life and to determine the appropriate distribution using 3 levels of traffic loads (high, medium, low) based on maintenance and rehabilitation history data for 15 years. RESULTS: As a result, Lognormal distribution is suitable for explanation of pavement lifetime in Daejeon area regardless of traffic loads. In addition, we found that the results of mean life and maintenance timing based on NHPCI for the pavement sections of 3 levels of traffic loads are available. CONCLUSIONS: Based on this study, it was found that mean life of high, medium and low levels of traffic loads are about 8.1 years, 12.2 years and 12.7 years, respectively. Higher level of traffic loads shorten the pavement mean life.

• Transactions of the Korean hydrogen and new energy society
• /
• v.15 no.2
• /
• pp.119-128
• /
• 2004

DME(Dimethyl Ether) was directly produced from the synthesis gas using the slurry phase reactor. The catalyst for DME production prepared two types (A type; Cu:Zn:Al=57:33:10, B type; Cu:Zn:Al=40:45:15, molar ratio). It was evaluated for the effect of the reaction medium oil using the small size slurry phase reactor. DME production yield and the methanol selectivity decreased in the order: n-hexadecane oil> mineral oil> therminol oil. The long-term test of DME production was carried out using A and B type catalyst, and n-hexadecane oil and mineral oil, respectively. It was confirmed that the use of A type for the catalyst and n-hexadecane for the reaction medium oil was very useful for the viewpoint of the DME production form the synthesis gas.

• Journal of Digital Convergence
• /
• v.15 no.10
• /
• pp.133-150
• /
• 2017

In this study, the performance of the technological innovation of small and medium enterprises is divided into short-term aspects of technological innovation and long-term aspects of ambidextrous innovation, and the effects of dynamic capabilities affecting these achievements are explored. For the purpose of conducting empirical analysis, the survey conducted a survey of 219 small businesses belonging to various industries, and dynamic capabilities performed a parallel multi-parameter analysis to demonstrate the effectiveness of technological innovation performance, including exploratory innovation and exploitative innovation. Through this study, it aims to understand the dynamic capabilities of the small and midsize enterprises and provide suggestions on how to manage of the company, thereby improving the understanding of dynamic capabilities and helping to improve the management of small and medium-sized enterprises.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.37 no.5
• /
• pp.81-89
• /
• 1995

One of the most difficult problem to estimate the flood inflow is how to understand the effective rainfall. The effective rainfall is absolutely influenced by the condition of soil moisture in the watershed just before the storm event. DAWAST model developed to simulate the daily streamflow considering the meteologic and geographic characteristics in the Korean watersheds was applied to understand the soil moisture and estimate the effective rainfall rather accurately through the daily water balance in the watershed. From this soil moisture and effective rainfall, concentration time, dimensionless hydrograph, and addition of baseflow, the rainfall-runoff model for flood flow was developed by converting the concept of long-term runoff into short-term runoff. And, real-time flood forecasting model was also developed to forecast the flood-inflow hydrograph to the river and reservoir, and called RETFLO model. According to the model verification, RETFLO model can be practically applied to the medium and small river and reservoir to forecast the flood hydrograph with peak discharge, peak time, and volume. Consequently, flood forecasting and warning system in the river and the reservoir can be greatly improved by using personal computer.

• Journal of the Korean Institute of Rural Architecture
• /
• v.17 no.1
• /
• pp.65-72
• /
• 2015

Recently the concerns of aging & care according to the aged Society were on the increase about Home for the elderly facility. In order to moment, the purpose of this study is to analyze planning direction and Architectural Environments in medium and small scale Elderly Care Facilities. This survey are used to investigate with latest building data, which is Long-term Care Insurance Code for the Elderly was started on July 2008 in Korea. The results of this paper are as follows. First, various type of home for the elderly and the elderly group homes are spread out, attached to day care center type, nursing home type, city region type, countryside rural type, near the university and remodeling type. Secondly, per capita room area-$6.32m^2$ are sufficient in regal comparison with $6.6m^2$. Thirdly, Sunlight environments is inappropriate condition as south direction proportion-41.95%. According to the present situation various facility type and model for our baby boomers generation should be more developed with preemptive systems of senior welfare concept.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2019.10a
• /
• pp.37-37
• /
• 2019

Cryopreservation is one of the ideal and suitable methods for long-term storage of plant germplasm. The plant contaminated with diseases and pathogens are decreased the multiplication rate, survival rate and high quality of plants after cryopreservation. The aim of this work was to improve a micropropagation method for lily in Korea, which are cultivars and indigenous plant. In the last process of rinsing scales after surface-sterilization, we tried to control the diseases and pathogens lived within the tissue by rinsing in 0.03% sodium hypochlorite (NaClO) instead of sterile distilled water. Bulb scales of Lilium were cultured in vitro on MS medium supplemented with Plant Preservative Mixture (PPM). The newly small bulb formed from bulb-scales was transferred to MS medium. We checked the non-contamination and survival rate after 2 weeks in culture. Non-contamination was shown to be 70 to 90% in formed small bulbs. This study will help to mitigate microbial contamination in Lilium species micropropagation for cryopreservation.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.30 no.2
• /
• pp.133-141
• /
• 2008

Stem cells have self-renewal capacity, long-term viability, and multiline age potential. Adult bone marrow contains mesenchymal stem cells. Bone marrow-derived mesenchymal stem cells (BMSCs) are progenitors of skeletal tissue components and can differentiate into adipocytes, chondrocytes, osteoblasts, and myoblasts in vitro and undergo differentiation in vivo. However, the clinical use of BMSCs has presented problems, including pain, morbidity, and low cell number upon harvest. Recent studies have identified a putative stem cell population within the adipose tissue. Human adipose tissue contains pluripotent stem cells simillar to bone marrow-derived stem cells that can differentiate toward the osteogenic, adipogenic, myogenic, and chondrogenic lineages. Human adipose tissue-derived stem cells (ATSCs) could be proposed as an alternative source of adult bone marrow stem cells, and could be obtained in large quantities, under local anesthesia, with minimal discomfort. Human adipose tissue obtained by liposuction was processed to obtain ATSCs. In this study, we compared the osteogenic differentiation of ATSCs in a specific osteogenic induction medium with that in a non-osteogenic medium. ATSCs were incubated in an osteogenic medium for 28 days to induce osteogenesis respectively. Osteogenic differentiation was assessed by von Kossa and alkaline phosphatase staining. Expression of osteocyte specific bone sialoprotein, osteocalcin, collagen type I and alkaline phosphatase, bone morphogenic protein 2, bone morphogenic protein 6 was confirmed by RT-PCR. ATSCs incubated in the osteogenic medium were stained positively for von Kossa and alkaline phosphatase staining. Expression of osteocyte specific genes was also detected. Since this cell population can be easily identified through fluorescence microscopy, it may be an ideal source of ATSCs for further experiments on stem cell biology and tissue engineering. The present results show that ADSCs have an ability to differentiate into osteoblasts. In the present study, we extend this approach to characterize adipose tissue-derived stem cells.

• Economic Analysis
• /
• v.27 no.1
• /
• pp.1-36
• /
• 2021

Given the US dollar's status as a global safe haven, global factors, such as US monetary policy, may have considerable impacts on financial markets in other countries. Regarding such hypothesis, this paper looked at the impacts of US monetary policy on domestic bond and FX swap markets through an event study. According to our analysis, US monetary policy had significant positive impacts on domestic interest rates. In particular, it turned out to have bigger impacts on long-term products with high term premiums. By period, the correlation between US monetary policy and domestic interest rates was not significant before the financial crisis, but was clearly positive after the crisis. The US conventional monetary policy was seen to have big impacts on short-term and medium-term KTB yields, while its unconventional monetary policy had major impacts on long-term KTB yields. Moreover, FX swap rates reacted very sensitively to US monetary policy shocks before the financial crisis, while they did not show any significant reactions after the crisis. This suggests that, in line with the covered interest rate parity, the impact of US monetary policy shocks was transmitted to domestic financial markets mainly through swap rate adjustments before the global financial crisis, but through the changes in domestic interest rates during the post-crisis period.

• Korean Journal of Plant Tissue Culture
• /
• v.21 no.2
• /
• pp.69-76
• /
• 1994

Callus growth and shoot regeneration of Solanum and Lycopersicon depended on genotype, growth regulators, and thiamine concentration. L. peruvianum LA 1277 and L. peruvianum LA 1373 and PI 251301 had the greatest callus growth while L hirsutum LA 1777, L.esculentum 'Diego'and 'Red Plum' had the least callus growth. Lycopersicon penvianum genotypes were superior to L. esculentur genotypes in regenerating plants. MG medium was more effective in regenerating shoots than MS medium. A low level of IAA (0.2mg/L) and high level of BA (2 mg/L) resulted in the greatest shoot regeneration. Shoot growth varied depending on thiamine concentration and genotype. Shoot proliferation of Solanum ptycathum, Solanum nigrum, and L. peruvianum PI 199380 was best on medium with 20 mg/L thiamine. Regeneration of L. peruvianum PI 251301 and PI 128652 was better on medium with 30 and 10mg/L thiamine, respectively.