• Korean Journal of Food Science and Technology
• /
• v.26 no.5
• /
• pp.585-589
• /
• 1994

The effects of T-2 toxin on mitogen-induced blastogenesis of chick splenic cells were investigated. The [$^3H$] thymidine incorporation in splenic cells stimulated by lipopolysaccharide and concanavalin A were equally inhibited as the concentration of T-2 toxin was increased. The effective dose of T-2 toxin causing a 50% reduction of [$^3H$] thymidine incorporation was inbetween 1.0 and 5.0 ng/ml for both mitogens. Mitogen-induced blastogenesis in chick splenic cells showed differences among experimental groups with different exposure time of T-2 toxin, exhibiting the most inhibition in the experimental group exposed to T-2 toxin at both embryonic and chick periods.

• Toxicological Research
• /
• v.15 no.1
• /
• pp.35-38
• /
• 1999

RNA synthesis rate was measured at different time points after UV irradiation in various xeroderma pigmentosum (XP) cells including complementation groups F and G. The RNA synthesis was assayed by measuring 3H-uridine incorporation. In normal cells, recovery of RNA synthesis was initiated at about 6 hr ager UV irradiation and reached to the same level as in unirradiated cells at 24hr after UV irradiation. By contrast, no such recovery was observed in group F,G XP cells.

• Journal of Plant Biology
• /
• v.25 no.4
• /
• pp.181-188
• /
• 1982

Chloroplasts isolated from tobacco (Nicotiana tabacum L. cv. Virginia 115) leaves have been transferred into protoplasts of soybean (Glycine max Merr. cv. Jangyeop) suspension-cultured cells with the help of polyethylene glycol (PEG). The increased yield in protoplasts of chloroplast uptake was depended upon the concentration of both PEG 4,000 and PEG 6,000. The highest yield(36%) occurred at 50% of both PEG, and the yield was decreased above this concentration. The rate of uptake with the incubation time was highest at one hour, then decreased. The process of the chloroplast uptake into the protoplasts was similar with that of a protoplast fusion, except forming invagination during uptake.

• Journal of Digital Convergence
• /
• v.19 no.12
• /
• pp.175-182
• /
• 2021

Focusing on the recently announced "KOSPI 200 ESG Index," this study intends to examine whether the "KOSPI 200 ESG Index" has any relevance to stock prices. Specifically, it was empirically analyzed whether companies included in the KOSPI 200 ESG index showed average abnormal return and cumulative average abnormal return of stock prices due to incorporation into the index. As for the research method, the case study was conducted using the return by the market model using the coefficient estimated by the OLS for the normal expected return. The study results are summarized as follows. First, the initial incorporation of a company into the KOSPI 200 ESG index showed significant positive(+) average abnormal return and cumulative average abnormal return. Second, the incorporation of a company into the KOSPI 200 ESG index showed significant positive(+) average abnormal return and cumulative average abnormal return. Through this study, it was confirmed that investors in the market are aware of ESG indicators as non-financial information, not just financial information. In addition, it can be said that the contribution of this study to the fact that investors perceive ESG index as information for investment. This study differs in that it uses the latest ESG index, but at the same time, it has limitations in that the study period is short and the study sample is limited.

• Journal of Industrial Technology
• /
• v.27 no.B
• /
• pp.245-253
• /
• 2007

Failure rate serves as a pivotal role in reliability study. Of all, the constant failure rate is the most popularly used in field exercises. In reality, however, the electrical and electronic parts' life is represented by not only the constant failure rate but the decreasing and/or increasing failure rates. Explicit consideration and incorporation of them into the model development may yield more desirable results. In this study, we built a reliability model for failure rates varying over time intervals and derived well known measures such as probability density function, reliability function, mean life, moments, and mission time. We then evaluated mean life with consideration of the first-year multiplier and compared the results those with constant failure rate. The results given in the study may provide a reference applying for practical decision making.

• Nuclear Engineering and Technology
• /
• v.56 no.5
• /
• pp.1627-1637
• /
• 2024

This research paper proposes a novel methodology for predicting the optimal location of friction supports to effectively mitigate vibrational energy in piping systems. The incorporation of friction forces in the dynamic characteristics of the system introduces inherent nonlinearity, making its analysis challenging. Typically, numerical solutions in the time domain are employed to circumvent the complexities associated with finding analytic solutions for nonlinear systems. However, time domain analysis (TDA) can be computationally intensive and demand significant computational resources due to the intricate calculations stemming from nonlinearity. To address this computational burden, this study presents an efficient approach based on linear analysis to predict the ideal position for installing friction supports as a replacement for fixed supports. Furthermore, we investigate the relationship between the installation positions of friction supports and their effectiveness in absorbing vibrations using the harmonic balanced method (HBM). Both methodologies are validated by comparing the obtained results with those obtained through time domain analysis (TDA) using the finite element method (FEM).

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
• /
• v.4 no.1
• /
• pp.11-19
• /
• 2008

Groundwater flow in confined aquifer and heat transport in underground geologic media are using same governing equation(line source) like well fuction. Therefore the conventional slope method using only later data obtained from in-situ thermal response test to determine the thermal conductivity of vertical geothermal heat exchanger(GHEX) is basically identical with one of Theis straight line method of aquifer test under artesian condition. In case that the pumping rate(Q, $m^3$/d) and drawdown(s,m) which are used for input data of existing hydrogeologic computer programs for aquifer test are replaced and converted to supplying heat energy per unit length of bore hole(Q/L,w/m or Kcal/h.m) and temperatures (T,$^{\circ}C$)measured at in and out-let of GHEX as in put data respectively, thermal conductivity around geothermal heat exchanger can be easily estimated without any special modification of the existing hydrogeologic computer program. Two numbers of time series temperature variation data obtained from in situ geothermal response test are analized using Theismethods(standard curve and straight line method) by using existing aquifer test program and conventional Slope method proposed by ASHRAE. The results show that thermal conductivity values estimated by two straight methods are identical and the difference of estimated values between standard curve methods and Slope method are also within acceptable ranges. In general,the thermal conductivity estimated from Theis straight linemethod gives more accurate value than the one of Slope method due to that Slope method uses only visual matching otherwise Theis method uses automatic curve matching estimation with reducing RSS.

• Journal of the Korean Ceramic Society
• /
• v.54 no.2
• /
• pp.108-113
• /
• 2017

The use of aluminum-based coagulants in water pretreatment is being carefully considered because aluminum exposure is a risk factor for the onset of Alzheimer's disease. Lightly burned-dolomite kiln dust (LB-DKD) was evaluated as an alternative coagulant because it contains high levels of the healthful minerals calcium and magnesium. An organic pore forming agent (OPFA) was incorporated to prepare porous granules after OPFA removal through a thermal decomposition process. A spray drying method was used to produce uniform and reproducible spherical granules with low density, since fine dolomite particles have irregular agglomeration behavior in the hydration reaction. The use of fine dolomite powder and different porosity granules led to a visible color change in raw algae (RA) containing water, from dark green to transparent colorlessness. Also, dolomite powders and granules exhibited a mean removal efficiency of 48.3% in total nitrogen (T-N), a gradual increase in the removal efficiency of total phosphorus (T-P) as granule porosity increased. We demonstrate that porous dolomite granules can improve the settling time and water quality in summer seasons for the emergent treatment of excessive algal blooms in eutrophic water.

• The Journal of Pediatrics of Korean Medicine
• /
• v.35 no.2
• /
• pp.11-20
• /
• 2021

Objectives The purpose of the study is to evaluate the safety of the Allium Fistulosum extract in children and its effectiveness in height growth. Methods This study is randomized, double-blind, placebo-controlled trial. The participants are children between the 3rd and 25th percentiles in height, and between the ages of 5 and 12 years. They are randomly assigned to treatment group or control group. The treatment group will take 5 g (1 g as Allium Fistulosum extract) for 24 weeks, 1 time a day. The control group will take the 5 g (0 g as Allium Fistulosum extract) of placebo for 24 weeks, 1 time a day. The primary outcome is change in height, and the secondary outcomes are growth rate, height standard deviations, Insulin-like growth factor-1 (IGF-1), Insulin-like growth factor binding protein-3 (IGFBP-3), IGF1-1/IGFBP-3 ratio, growth hormone, bone age, osteocalcin, and Z-score for growth. Results This protocol has been approved by the institutional review board (IRB) of Daejeon Korean Medicine Hospital of Daejeon University (IRB No. DJDSKH-20-BM-15), and registered in the Clinical Research Information Service (CRIS) (Registry No. KCT0005981). Conclusions This study will provide clinical information about the effectiveness and safety of Allium Fistulosum extract in children for their growth.

• Ecology and Resilient Infrastructure
• /
• v.3 no.4
• /
• pp.307-314
• /
• 2016

River restoration has recently been performed not only for the improvement of the artificial parts in the past but also for the restoration of abandoned river reaches which were blocked and isolated. For the restoration of abandoned river reaches, it is important to recover the hydraulic and ecological connectivity in the isolated space by longitudinal structures like levees. But because the assessment tools to determine whether the river restoration is performed properly are so rare at present, we aim to provide a tool for assessing ecological connectivity in a target river in this study. In the first step, one-dimensional numerical model for rainfall-runoff and channel routing was developed and then applied to the watershed of the Cheongmi Stream. In this step, a numerical model was developed to assess the restoration of connectivity. The model consists of two parts: one part is to convert the results of one-dimensional channel routing into two-dimensional spatial distribution. The other is to calculate the habitat suitability index according to time steps by using two-dimensional hydraulic features. The model was applied to a restoration area of the Cheongmi Stream. The advantage of this study is that two-dimensional hydraulic analysis can be easily obtained from one-dimensional hydraulic analysis without a complex and time-consuming two-dimensional analysis. HHS (Hydraulic Habitat Suitablility) by sections of target reaches and target species can be easily obtained using the results of this study.