• Title/Summary/Keyword: Growth time

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Effect of PWHT on Variability of fatigue Crack Propagation Resitance in TIG Welded Al 6013-T4 Aluminum Alloy (TIG 용접된 Al6013-T4 알루미늄 합금에서 피로균열전파저항의 변동성에서의 PWHT의 영향)

  • Haryadi, Gunawan Dwi;Lee, Sang-Yeul;Kim, Seon-Jin
    • Journal of Power System Engineering
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    • v.15 no.6
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    • pp.73-80
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    • 2011
  • The experimental investigation focuses on an influence of artificial aging time in longitudinal butt welded Al 6013-T4 aluminum alloy on the fatigue crack growth resistance. The preferred welding processes for this alloy are frequently tungsten inert gas welding (TIG) process due to its comparatively easier applicability and better weldability than other gas metal arc welding. Fatigue crack growth tests were carried out on compact tension specimens (CT) in longitudinal butt TIG welded after T82 heat treatment was varied in three artificial aging times of 6 hours, 18 hours and 24 hours. Of the three artificial aging times, 24 hours of artificial aging time are offering better resistance against the growing fatigue cracks. The superior fatigue crack growth resistance preferred spatial variation of materials within each specimen in the Paris equation based on reliability theory and fatigue crack growth rate by crack length are found to be the reasons for superior fatigue resistance of 24 hours of artificial aging time was compared to other joints. The highest of crack propagation resistance occurs in artificial aging times of 24 hours due to the increase in grain size (fine grained microstructures).

Vertically Standing Graphene on Glass Substrate by PECVD

  • Ma, Yifei;Hwang, Wontae;Jang, Haegyu;Chae, Heeyeop
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.232.2-232.2
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    • 2014
  • Since its discovery in 2004, graphene, a sp2-hybridized 2-Dimension carbon material, has drawn enormous attention. A variety of approaches have been attempted, such as epitaxial growth from silicon carbide, chemical reduction of graphene oxide and CVD. Among these approaches, the CVD process takes great attention due to its guarantee of high quality and large scale with high yield on various transition metals. After synthesis of graphene on metal substrate, the subsequent transfer process is needed to transfer graphene onto various target substrates, such as bubbling transfer, renewable epoxy transfer and wet etching transfer. However, those transfer processes are hard to control and inevitably induce defects to graphene film. Especially for wet etching transfer, the metal substrate is totally etched away, which is horrendous resources wasting, time consuming, and unsuitable for industry production. Thus, our group develops one-step process to directly grow graphene on glass substrate in plasma enhanced chemical vapor deposition (PECVD). Copper foil is used as catalyst to enhance the growth of graphene, as well as a temperature shield to provide relatively low temperature to glass substrate. The effect of growth time is reported that longer growth time will provide lower sheet resistance and higher VSG flakes. The VSG with conductivity of $800{\Omega}/sq$ and thickness of 270 nm grown on glass substrate can be obtained under 12 min growing time. The morphology is clearly showed by SEM image and Raman spectra that VSG film is composed of base layer of amorphous carbon and vertically arranged graphene flakes.

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Effects of Yongohkgo on Growth and Learning Ability in Growth Deficiency Rat With Linsufficient Nutrition Diet (영양소 결핍으로 유도한 성장장애 흰쥐에서 용옥고(龍玉膏)가 성장 및 학습효과에 미치는 영향)

  • Kong, In-Pyeo;Cha, Yun-Yeop
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.3
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    • pp.624-629
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    • 2008
  • Effects of Kyungohkgo Ga Nokyong(Yongohkgo) on growth development and learning ability were investigated growth and intellectual impairment rat with insufficient nutrition diet. We divided male Sprague-Dawley rats into 4 groups. They were Normal group, Growth deficiency rat with insufficient nutrition diet group, Growth deficiency rat with 0.1% Yongohkgo group and 0.2% Yongohkgo group. They were administered for 5 weeks. We measured body weight, and morris water maze test in escape distance, escape time and escape speed, serum growth hormone, insulin-like growth factor and thyroid stimulating hormone, RBC, concentration of Hb and PCV ratio, total WBC and its composition, the values of GOT and GPT activities. The results are as follows that Yongohkgo 0.1%, 0.2% groups were showed significantly different than control groups in body weight and the counts of RBC. In the morris water maze test, in escape distance and escape time, in concentration of Hb and PCV ratio, 0.2% Yongohkgo group were significantly different than control groups. Serum growth hormone, insulin- like growth factor and thyroid stimulating hormone showed a tendency to increase in Yongohkgo groups. The counts of total WBC and its composition, GOT, GPT activities showed no significantly different in all treatment groups. These results suggested that Yongohkgo have an effect of promoting growth and learning ability of rats and might be effect to treat various kinds of growth and learning ability delay in children.

Analyzing Growth Factors of Alley Markets Using Time-Series Clustering and Logistic Regression (시계열 군집분석과 로지스틱 회귀분석을 이용한 골목상권 성장요인 연구)

  • Kang, Hyun Mo;Lee, Sang-Kyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.6
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    • pp.535-543
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    • 2019
  • Recently, growing social interest in alley markets, which have shown rapid growth like Gyeonglidan-gil street in Seoul, has led to the need for an analysis of growth factors. This paper aims at exploring growing alley markets through time-series clustering using DTW (Dynamic Time Warping) and examining the growth factors through logistic regression. According to cluster analysis, the number of growing markets of the Northeast, the Southwest, and the Southeast were much more than the Northwest but the proportion in region of the Northwest, the Northeast, and the Southwest were much more than the Southeast. Logistic regression results show that people in 20s and 30s have a lower impact on sales than those in 50s, but have a greater impact on growth of alley market. Alley markets located in high-income areas often reached their growth limits, indicating a tendency to stagnate or decline. The proximity of a subway station effected positive on sales but negative on growth. This research is an advanced study in that the causes of sales growth of alley markets is examined, which has not been examined in the preceding study.

Effects of Growth Temperature and Time on Properties of ZnO Nanostructures Grown by Electrodeposition Method (Electrodeposition에 의해 성장온도와 시간을 달리하여 성장한 ZnO 나노구조의 특성)

  • Park, Youngbin;Nam, Giwoong;Park, Seonhee;Moon, Jiyun;Kim, Dongwan;Kang, Hae Ri;Kim, Haeun;Lee, Wookbin;Leem, Jae-Young
    • Journal of the Korean institute of surface engineering
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    • v.47 no.4
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    • pp.204-209
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    • 2014
  • The electrodeposition of ZnO nanorods was performed on ITO glass. The optimization of two process parameters (solution temperature and growth time) has been studied in order to control the orientation, morphology, density, and growth rate of ZnO nanorods. The structural and optical properties of ZnO nanorods were systematically investigated by using field-emission scanning electron microscopy, X-ray diffractometer, and photoluminescence. Commonly, the results of the structural property show that hexagonal ZnO nanorods with wurtzite crystal structures have a c-axis orientation, and higher intensity for the ZnO (002) diffraction peaks. Furthermore, the nanorods length increased with increasing both the solution temperature and the growth time. The results of the optical property show a strong UV (3.28 eV) peaks and a weak visible (1.9~2.4 eV) bands, the intensity of UV peaks was increased with increasing both the solution temperature and the growth time. Especially, the UV peak for growth of nanorods at $75^{\circ}C$ blue-shift than different temperatures.

Effect of Plant Growth Regulators on Fruit Enlargement and Optimal Harvest Time in Sageretia thea (Osback) M. C. Johnst (생장조정제 처리가 상동나무 열매의 비대와 수확시기에 미치는 영향)

  • Song, Sang Churl;Song, Chang Khil;Kim, Ju Sung
    • Korean Journal of Medicinal Crop Science
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    • v.23 no.4
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    • pp.311-318
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    • 2015
  • This study had been conducted to investigate the effect of some plant growth regulators inducing fruit enlargement and optimal harvest time in Sageretia thea. Two hundred fifty $mg/{\ell}$ mepiquat chloride treatment, $1mg/{\ell}$ thidiazuron treatment on full bloom, and $200mg/{\ell}$ gibberellic acid treatment on 7 days before full bloom resulted in the increase of 21.7% in weight, and $200mg/{\ell}$ gibberellic acid treatment 7 days before full bloom, 10$mg/{\ell}$ forchlorfenuron treatment 14 days after full bloom, and $1mg/{\ell}$ thidiazuron treatment on full bloom also brought about positive effects on the enlargement of the fruit, increasing 6.3%, 6.3% and 8.1% in its transverse diameter, respectively. Furthermore, the effects of the plant growth regulator treatments on the harvest time of Sageretia thea were determined as follows: the increase in the optimal harvest time of 57.2 - 75.4%, shorter maturation period, by the treatments with $500mg/{\ell}$ mepiquat chloride 7 days after full bloom, $100mg/{\ell}$ gibberellic acid treatment on full bloom, $2.5mg/{\ell}$ forchlorofenuron 7 days after full bloom and $2mg/{\ell}$ thidiazuron treatment 7 days before full bloom; and the greater effects of plant growth regulator treatments on the fruit maturation in the following order, gibberellic acid > thidiazuron > forchlorofenuron > mepiquat chloride. The results of this study are expected to be used as a reference data to develop Sageretia thea as a new local specific crop for Jeju island.

A Study on Complementarity of Green Growth (녹색성장의 상보성에 관한 연구)

  • PARK, Seong-Kwae
    • Journal of Fisheries and Marine Sciences Education
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    • v.21 no.2
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    • pp.306-324
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    • 2009
  • The purpose of this study is to analyze green growth issues such as employment, education and training, social capital and nature's standing right from the complementary perspective between natural environment conservation and economic growth. Green growth can be defined as a growth which lowers an increasing rate of entropy and at the same time improves our living standard. Green growth paradigm requires a quite amount of understanding the laws of thermodynamics and the uncertainty principle as the highest orders which regulate our overall socio-economic behaviors. They suggest that socio-economic growth is a mere transformation process of natural energy from one form to another and they increases natural manmade entropy over time. The most important issue of green growth policy may be a problem concerning employment and/or unemployment since green growth may induce inevitable movement of resources from the existing industries to the green sector. In particular, green industries will demand more highly specialized manpower than the existing ones. Without a well-designed new training education system and social capital accumulation toward environmental concerns, green growth may accompany a substantial amount of structural involuntary frictional unemployment. This may increase not only wealth-distribution disparity but also political instability. In order to achieve harmonious green growth, we should recognize that there are important complementary relationships between green and growth. Our society should also be able to innovate the existing educational system to accumulate social capital, to create a new sharing system, and to admit nature's standing right. Although the 2003 lawsuit case of Korean Salamander in Cheonseong Mountain went against plaintiff, it would provide apparently our society with a way of green development ahead.

Validation of Broth Model for Growth of Bacillus cereus in Blanched Vegetables (전처리 나물류에서 Bacillus cereus 성장 예측 모델 검증)

  • Jo, Hye-Jin;Hong, Soo-Hyun;Kim, Young-Gyo;Shin, Dan-Bi;Oh, Myung-Ha;Hwang, Jeong-Hee;Lkhagvasarnai, Enkhjargal;Yoon, Ki-Sun
    • Journal of the East Asian Society of Dietary Life
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    • v.22 no.4
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    • pp.558-565
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    • 2012
  • The objective of this study was to develop a predictive growth model for Bacillus cereus in nutrient broth and validate the developed growth model in blanched vegetables. After inoculating B. cereus into nutrient broth, growth of B. cereus was investigated at 13, 17, 24, 30 and $35^{\circ}C$. Lag time (LT) decreased while specific growth rate (SGR) increased with an increase in storage temperature. Growth of B. cereus was not observed at temperatures lower than $12^{\circ}C$. Secondary growth models were developed to describe primary model parameters, including LT and SGR. Model performance was evaluated based on bias factor ($B_f$) and accuracy factor ($A_f$). In addition, we inoculated B. cereus into blanched vegetables stored at 13, 24, $35^{\circ}C$ and observed the growth kinetics of B. cereus in five different blanched vegetables. Growth of B. cereus was most delayed on Doraji at $13^{\circ}C$ and was not observed on Gosari at $13^{\circ}C$. Growth of B. cereus at $35^{\circ}C$ was significantly (p<0.05) slower on Gosari than on other blanched vegetables. The developed secondary LT model for broth in this study was suitable to predict growth of B. cereus on Doraji and Gosari, whereas the SGR model was only suitable for predicting the growth of B. cereus on mung bean sprout.

Analysis Method of the Effect of National R&D investments on Economic Growth

  • Choi, Eun-Chul
    • Journal of Technology Innovation
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    • v.7 no.2
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    • pp.1-20
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    • 1999
  • This paper investigates the effects of various R&D investments on economic growth empirically. To this end, the relationships between various R&D investments and economic growth are analysed, and the rates of return of R&D investments are estimated. Furthermore, the effect of government R&D investment on private sector R&D investment, and the effect of social factors, which affect the relationship between the R&D inputs and economic growth, are analysed. Based on the results of this analysis, a simulation model is developed, which shows the relationship between R&D investments and economic growth rate; this model is verified by analysing the correlation between the actual and the estimated economic growth rate, using the data between 1981 and 1995 of eight selected countries. The validation results show that the simulation model has sufficient accuracy to be used for evaluating and proposing R&D policies for the countries for which appropriate data is available. However, the time-lag effect, which is naturally believed to exist between the R&D input and the economic growth, could not be analysed in a mathematical form, because of the lack of the data to establish this relationship. Thus, when estimating the relationship between them, the time-lag effect in this relationship was included implicitly by using the data of fifteen years.

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The Effect of Banking Industry Development on Economic Growth: An Empirical Study in Jordan

  • ALMAHADIN, Hamed Ahmad;AL-GASAYMEH, Anwar;ALRAWASHDEH, Najed;ABU SIAM, Yousef
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.5
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    • pp.325-334
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    • 2021
  • This study aims to investigate whether economic growth is elevated by banking industry development in Jordan. The study adopts time-series econometric methodologies, which comprise the bounds testing approach within the autoregressive distributed lag (ARDL) and the conditional causality analysis. Consistent with the assumptions of the adopted methodology, the study utilized annual time-series data for a relatively long period of thirty-nine years, between 1980 and 2018. The empirical results show that Jordan's economic growth is strongly responsive in respect to any changes in banking industry development. Also, the results reveal the harmful impact of rising lending interest rate; as this rate increases, economic growth will decrease. The findings are in line with the conceptual arguments of the supply-leading hypothesis, which confirmed that banking development is considered as one of the main pillars that have stimulating effects on economic growth. The evidence of the current study may provide important implications for policymakers and bankers. Those professionals should work to maintain a stable regulatory system that enhances the banking system function in activating economic growth. Also, a considerable focus should be placed on designing a steady interest rate policy to avoid the inherently undesirable impacts of high-interest rates on the Jordanian economy.