• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권2호
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• pp.98-102
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• 2000

Ferroelectric PZT heterolayered thin films were fabricated by spin coating method on the Pt/Ti/SiO2/Si substrate using PZT(10/90) and PZT(90/10) m7etal alkoxide solutions. All PZT heterolayered films showed a homogeneous grain structures without presence of rosette structure. It can be assumed that the lower PZT layers played a role of nucleation site for the formation of the upper PZT layer. Pb-deficient PZT phase was formed at PZT/Pt interface due to the diffusion of Pb element into a Pt bottom electrode. The relative dielectric constant and the dielectric loss of the PZT-6 film were 567 and 3.6%, respectively. Increasing the number of coatings, remanent polarization and coercive field were decreased and the values of the PZT-6 heterolayered film were $7.18\muC/cm^2$ and 68.5kV/cm, respectively. Leakage current densities were increased with increasing the number of coatings, and the value of the PZT-4 film was about $7\times10-8A/cm^2$ at 0.05MV/cm.

• 한국컴퓨터정보학회논문지
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• 제21권12호
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• pp.139-145
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• 2016

In this paper, we propose to evaluate the effect of Resistin-like molecule alpha (Retnla) on the expression of transporters involved in modulating concentrations of peripheral cholesterol and plasma high-density lipoprotein (HDL) cholesterol. High levels of blood cholesterol are a well-recognized risk factor for atherosclerosis and are eliminated via the process of reverse cholesterol transport (RCT). We recently showed that Retnla ameliorates hypercholesterolemia and atherosclerosis by increasing biliary cholesterol secretion, the final step of the process, in low-density lipoprotein receptor-deficient mice. However, the role of Retnla in HDL-mediated cholesterol efflux, initial step of RCT pathway, is not yet clear. To identify cholesterol transport genes regulated by Retnla, we performed an extensive microarray-based gene expression screen using livers from Retnla-overexpressing (Tg) mice and control animals. The most significant change in Retnla-Tg mice was an upregulation of ATP-binding cassette sub-family G member 4 (Abcg4) transport and was validated using quantitative RT-PCR. The validated gene was also induced by treatment of purified Retnla protein in RAW 264.7 cells incubated with acetylated low-density lipoprotein and Hepa1c1c7 cells. Taken together, these results indicates that Retnla might also accelerate initial step of RCT pathway, suggesting therapeutic value of Retnla in the treatment of hypercholesterolemia and atherosclerosis.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.252-252
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• 2007

$Al_2O_3-TiO_2$(AT)ceramics shows great promise as a dielectric material for millimeter-wave use. The sintering temperature of AT ceramics was approximately $1450^{\circ}C$ and decreased to $900^{\circ}C$ with the addition of BaCu(B2O5) (BCB) ceramic powder. The presence, of the liquid phase was responsible for the decrease of the sintering temperature. The liquid phase is considered to have a composition similar to the BaO-deficient BCB. The Q-value initially increased with the addition of BCB, but decreased considerably when a large amount of BCB was added, because of the presence of the liquid phase. Good microwave dielectric properties of $Q{\times}f\;=\;16,200\;GHz$, ${\varepsilon}_r\;=\;9$ and ${\tau}_f\;=\;-4\;ppm/^{\circ}C$ were obtained for the 20.0 mol% BCB-added AT ceramics sintered at $900^{\circ}C$ for 2 h.

• 한국토양비료학회지
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• 제44권4호
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• pp.551-558
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• 2011

The aim of this study was to know whether leaf nitrate can be a substitute of total leaf N to justify plant N status and how nitrate influences macro elements uptake and physiological parameters of tomato plants under different nitrogen levels. Leaf nitrate content decreased in low N, while showed similar value with the control in high N, ranging from 55 to $70mg\;g^{-1}$. Differences in nitrate supply led to nitrate-dependent increases in macro elements, particularly cations, while gradual decrease in P. Physiological parameters, photosynthesis rates and antioxidants, greatly responded in N deficient conditions rather than high N, which didn't show any significant differences compared the control. Considering nitrogen forms and physiological parameters, total-N in tomato plants represented positive relation with growth (shoot dry weight), nitrate and $CO_2$ assimilation, whereas negative relation with lipid peroxidation.

• Asia Pacific Journal of Business Review
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• 제5권2호
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• pp.19-44
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• 2021

Sub Saharan Africa (SSA) is receiving increased investments in the energy sector under the belt and road initiative (BRI) project since its inception in 2013. SSA has a worse energy efficiency ratio coupled with deficient electricity access, through analysis showed varied impacts on the SSA countries due to the BRI initiative. This study dilves into the influencing factors for Energy Efficiency (EE) in 38 SSA countries, applying the probit and logit approach for 2000-2018. The Multiple-regression model shows significant results of some variables such as foreign direct investment, gross domestic product, and port infrastructure quality being significant on EE under BRI initiative countries. However, the logit and probit models produce similar results and the marginal effect for the entire variable, except energy imports that do not likely impact EE. Furthermore, the interaction of quality of port infrastructure and foreign direct investment variables produces significant results, highlighting the increased investments SSA receives under the BRI initiative in the energy and transport sectors. The model Percent correctly predicted (PCP) value was about 84%, indicating it correctly classified the variables and about 16% not classified. The study recommends EE performance standards should be incorporated on energy projects in SSA to ensure that these projects are energy efficient and decouple SSA's energy demand from economic growth. The research proffers suggestions for policy regarding the BRI initiative in SSA and the implications on sustainable energy and building a community with a shared future.

• 한국지진공학회논문집
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• 제28권2호
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• pp.113-119
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• 2024

Existing reinforced concrete buildings with seismically deficient column details affect the overall behavior depending on the failure type of column. This study aims to develop and validate a machine learning-based prediction model for the column failure modes (shear, flexure-shear, and flexure failure modes). For this purpose, artificial neural network (ANN), K-nearest neighbor (KNN), decision tree (DT), and random forest (RF) models were used, considering previously collected experimental data. Using four machine learning methodologies, we developed a classification learning model that can predict the column failure modes in terms of the input variables using concrete compressive strength, steel yield strength, axial load ratio, height-to-dept aspect ratio, longitudinal reinforcement ratio, and transverse reinforcement ratio. The performance of each machine learning model was compared and verified by calculating accuracy, precision, recall, F1-Score, and ROC. Based on the performance measurements of the classification model, the RF model represents the highest average value of the classification model performance measurements among the considered learning methods, and it can conservatively predict the shear failure mode. Thus, the RF model can rapidly predict the column failure modes with simple column details.

• Journal of Nutrition and Health
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• 제15권1호
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• pp.70-79
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• 1982

Using dietary, anthropometric, and biochemical methods of evaluation, a nutritional survey was made of 81 seven-and eight-year-old children from two schools with different socioeconomic backgrounds in Daejon city, during the October of 1980. All the children were tall and heavy in comparison with 1976 Korean standard. School A children with relatively high socioeconomic levels showed higher value in length and lower value in weight than school B children with relatively low socioeconomic levels. Mean hemoglobin values were 13.3 (school A) and 12.8 (school B) g/100 ml and hematocrits were 39.7 and 37.9%, respectively. Anemic children were not many in both schools ( A ; 0-25%, B ; 12.5-15.0% ). Urea nitrogen/creatinine ratios were 9.2 (A) and 7.8 (B). The intake of animal foods was higher in school A owing to the higher intake of milks. The intakes of all nutrients except energy and calcium were comparable to or higher than Korean recommend dietary allowances (KRDA). Riboflavin intake wae deficient in school B only. Low socioeconomic school B children had significantly lower intakes of fats, calcium, and riboflavin than school A children. Energy intakes were low as 75.9 (A) and 83.2 (B) % of KRDA but their composition of carbohydrates, fats, and proteins were satisfactory in both schools. More than one-third of protein intake was animalorigin in both schools (A ; 1.40/3, B ; 1.10/3) and calcium intake was very low as 59.0%(A) and 45.8%(B). Education levels of parents, esp. mothers, were positively correlated with Kaup indice (in school A & B) and some nutrients intakes (in school A). In school B, number of siblings and birth order showed negative correlations with some nutrient intakes.

• Asian-Australasian Journal of Animal Sciences
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• 제10권1호
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• pp.28-34
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• 1997

This study was conducted to determine the protein content, cell wall fractions, and mineral concentrations of some minor plant species collected for one year in pastures grazed by goats in the Philippines. An assessment of nutrient variability and a comparison of forage protein and mineral concentrations to the critical value of protein and minerals based on animal needs were also studied. The plant species were the following: grasses(Axonopus compressus, Eleusine indica, Rottboellia exaltata); legumes (Aeschynomene indica, Calopogonium muconoides, Desmodium tortousum); and herbs (Corchorus olitorius, Ipomea aquatica, Sida acuta, Synedrella nodiflora). The two seasons (dry and wet) were subdivided into Dry-1 (December to February, 132 mm total rainfall), Dry-2 (March to May, 25 mm total rainfall), Wet-1 (June to August, 1,138 mm total rainfall), and Wet-2 (September to November, 1,118 mm total rainfall). Results showed that significant differences were obtained on various nutrient fractions including those mineral concentrations across species. Across season, acid detergent lignin (ADL) had higher (p < 0.05) value at Dry-1. Legumes and herbs were higher in crude protein (CP) especially Sida acuta. Grasses showed the highest neutral detergent fiber (NDF) and acid detergent fiber (ADF) with the addition of Sida nodiflora (herb) for it contained high NDF. Aeschynomene indica contained the highest amount of ADL and the herbs (Ipomea aquatica and Sida acuta) had exceptionally high concentration of minerals. Coefficient variation of the various nutrient values ranged from 27.3 to 136.7%. Some forage minerals appeared to be deficient (sodium, phosphorus and copper) or excess (molybdenum) for the whole or part of the year. This study shows that some minor plant species could extend the range of concentration of some nutrients (i.e., CP and minerals) beyond that normally found in conventional pasture species.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권4호
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• pp.113-121
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• 2015

The contaminated soil at abandoned smelter areas present challenge for remediation, as the degraded materials are typically deficient in nutrients, and rich in toxic heavy metals and metalloids. Bioremediation technique is to isolate new strains of microorganisms and develop successful protocols for reducing metal toxicity with heavy metal tolerant species. The present study collected metal contaminated soil and characterized for pH and EC values, and heavy metal contents. The pH value was 5.80, representing slightly acidic soil, and EC value was 13.47 mS/m. ICP-AES analytical results showed that the collected soil samples were highly contaminated with various heavy metals and metalloids such as lead (183.0 mg/kg), copper (98.6 mg/kg), zinc (91.6 mg/kg), and arsenic (48.1 mg/kg), respectively. In this study, a bacterial strain, Bacillus cereus KM-15, capable of adsorbing the heavy metals was isolated from the contaminated soils by selective enrichment and characterized to apply for the bioremediation. The effects of heavy metal on the growth of the Bacillus cereus KM-15 was determined in liquid cultures. The results showed that 100 mg/L arsenic, lead, and zinc did not affect the growth of KM-15, while the bacterial growth was strongly inhibited by copper at the same concentration. Further, the ability of the bacteria to adsorb heavy metals was evaluated.

• 미생물학회지
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• 제37권4호
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• pp.305-311
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• 2001

다양한 식물병원성 진균을 방제하기 위하여 온천수로부터 1종의 동물병원성 진균과 12종의 식물병원성 진균에 항진균 활성을 갖는 고온성 세균을 분리하였으며 Bacillus subtilis YS1으로 동정되었다. 분리 균주의 감마선($Co^{60}$)에 대한 감수성 조사 결과, $D_{10}$ value는 2.08 kGy로 20 kGy 의 방사선량에서도 생존 가능한 방사선 저항성 균주였다. 방사선 조사를 이용하여 5종의 돌연변이체를 유기하였으며, 이 중 B. subtilis YS1-1009 돌연변이체는 Botryoshaeria dothidea에 대한 항진균 활성의 증가 및 4종의 식물병원성 진균에 대하여 항진균 활성이 감소하는 종특이적 항진균 활성 변화를 나타내었다. 또한 상용농약인 tebuconazole에 대하여 저항성을 나타내었으며 17종의 다른 농약에 대해서도 전체적으로 야생형 균주에 비해 저항성이 증가하였다. B. subtilis YS1-1006 돌연변이체는 copper hydroxide에 저항성을 나타내었으며, B. subtilis YS67 돌연변이체는 항진균 활성이 소실된 tryptophan 및 proline 또는 uracil 및 arginine 영양요구성 돌연변이체였다. 이러한 결과로부터 극한 환경에서 분리한 본 분리균주는 환경친화적으로 진균에 의한 식물병을 방제할 수 있으며 방사선을 이용한 돌연변이체 유기는 기능성 균주의 개량이나 작용기작 연구를 위한 돌연변이체의 획득에 매우 효과적인 방법이라 사료된다.