• Title/Summary/Keyword: growth factors

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A Study on Determinants of Photovoltaic Energy Growth: Panel Data Regression with Autoregressive Disturbance (태양광 보급의 결정요인 연구: 자기상관 패널데이터 분석)

  • Kim, Kwangsu;Choi, Jinsoo;Yoon, Yongbeum;Park, Soojin
    • Current Photovoltaic Research
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    • v.10 no.1
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    • pp.6-15
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    • 2022
  • Climate change is among the most important issues facing mankind in modern society. However, global PV energy expansion has been driven mainly by OECD countries. We investigate the determinants of PV energy growth by panel data of selected OECD countries from 1991 to 2018. We investigate four categories of driving factors: socioeconomic, technological, country specific, and policy factors. The test results support that PV capacity growth is significantly driven by technology development and multidimensional environment policy factors. Socioeconomic factors such as CO2, GDP, and electricity price are statistically significant on the growth of PV energy, too. Whereas, country-specific solar potential factor is the least related. As most of the socioeconomic factors are exogenous, we need to focus more on PV technology development and policy measures.

The Key Historical Factors of Small and Medium-Sized Enterprises (SMEs) for Economic Growth in the Republic of Korea

  • Eungoo KANG
    • Journal of Koreanology Reviews
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    • v.2 no.2
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    • pp.9-17
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    • 2023
  • The primary objectives of this study is to examine and identify the historical factors that have significantly contributed to the growth/ expansion and prosperity of SMEs in the Republic of Korea and to evaluate and assess the impact of historical factors on the economic progress/ development, innovation, and job creation within SMEs in South Korea. To achieve the purpose of the current study, the present author has investigated the comprehensive literature investigation and figured out a total of four Key historical factors of SMEs for Economic Growth in the Republic of Korea, such as (1) Government Policies, (2) Technological Advancements, (3) Access to Finance, (4) International Trade. In conclusion, this study has undertaken a thorough investigation into the four critical historical factors that have significantly affected the development and achievements of SMEs in the Republic of Korea. By addressing a notable gap in current scholarly work, this study not only adds to the existing pool of knowledge but also provides valuable insights for various stakeholders. Practitioners/ professionals should proactively participate in government support initiatives/ programs and financial aid. SMEs can benefit from monetary incentives and donations/ grants intended to stimulate research and development, creativity, and international trade ventures.

A Study on Relationship between Economic Growth and Pollution: Theoretical and Empirical Analysis (환경오염과 경제성장 간의 관계에 대한 모형구축 및 실증분석)

  • Kim, Ji Uk
    • Environmental and Resource Economics Review
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    • v.12 no.3
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    • pp.515-529
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    • 2003
  • This theoretical model makes three contributions to the study on economic growth and environment. First, emissions are generated during final goods production and technology accumulation. Second, this paper assumes that pollution is directly increasing with increase in final goods output or in consumption. Third, we use reproducible factors associated with labor and capital input in production function and assume constant return to scale in reproducible factors. From growth rate condition we derived, increases in reproducible factors, increases in productivity of either the abatment or technology sector, and decrease in social discount rate would increase the sustainable growth rate. In empirical test, the environmental degradation did not effect the economic growth rate though other factors satisfied the growth rate condition equation. However, through the reinterpretation of this result, we found indirectly the fact of that an inverted U relationship between air pollution and economic growth rate would exist in 20 OECD countries using a panel data for the period of 1986~1995.

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Estimation of Highland Kimchi Cabbage Growth using UAV NDVI and Agro-meteorological Factors

  • Na, Sang-Il;Hong, Suk-Young;Park, Chan-Won;Kim, Ki-Deog;Lee, Kyung-Do
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.5
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    • pp.420-428
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    • 2016
  • For more than 50 years, satellite images have been used to monitor crop growth. Currently, unmanned aerial vehicle (UAV) imagery is being assessed for analyzing within field spatial variability for agricultural precision management, because UAV imagery may be acquired quickly during critical periods of rapid crop growth. This study refers to the derivation of growth estimating equation for highland Kimchi cabbage using UAV derived normalized difference vegetation index (NDVI) and agro-meteorological factors. Anbandeok area in Gangneung, Gangwon-do, Korea is one of main districts producing highland Kimchi cabbage. UAV imagery was taken in the Anbandeok ten times from early June to early September. Meanwhile, three plant growth parameters, plant height (P.H.), leaf length (L.L.) and outer leaf number (L.N.), were measured for about 40 plants (ten plants per plot) for each ground survey. Six agro-meteorological factors include average temperature; maximum temperature; minimum temperature; accumulated temperature; rainfall and irradiation during growth period. The multiple linear regression models were suggested by using stepwise regression in the extraction of independent variables. As a result, $NDVI_{UAV}$ and rainfall in the model explain 93% of the P.H. and L.L. with a root mean square error (RMSE) of 2.22, 1.90 cm. And $NDVI_{UAV}$ and accumulated temperature in the model explain 86% of the L.N. with a RMSE of 4.29. These lead to the result that the characteristics of variations in highland Kimchi cabbage growth according to $NDVI_{UAV}$ and other agro-meteorological factors were well reflected in the model.

Human umbilical cord blood mesenchymal stem cells engineered to overexpress growth factors accelerate outcomes in hair growth

  • Bak, Dong Ho;Choi, Mi Ji;Kim, Soon Re;Lee, Byung Chul;Kim, Jae Min;Jeon, Eun Su;Oh, Wonil;Lim, Ee Seok;Park, Byung Cheol;Kim, Moo Joong;Na, Jungtae;Kim, Beom Joon
    • The Korean Journal of Physiology and Pharmacology
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    • v.22 no.5
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    • pp.555-566
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    • 2018
  • Human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) are used in tissue repair and regeneration; however, the mechanisms involved are not well understood. We investigated the hair growth-promoting effects of hUCB-MSCs treatment to determine whether hUCB-MSCs enhance the promotion of hair growth. Furthermore, we attempted to identify the factors responsible for hair growth. The effects of hUCB-MSCs on hair growth were investigated in vivo, and hUCB-MSCs advanced anagen onset and hair follicle neogeneration. We found that hUCB-MSCs co-culture increased the viability and up-regulated hair induction-related proteins of human dermal papilla cells (hDPCs) in vitro. A growth factor antibody array revealed that secretory factors from hUCB-MSCs are related to hair growth. Insulin-like growth factor binding protein-1 (IGFBP-1) and vascular endothelial growth factor (VEGF) were increased in co-culture medium. Finally, we found that IGFBP-1, through the co-localization of an IGF-1 and IGFBP-1, had positive effects on cell viability; VEGF secretion; expression of alkaline phosphatase (ALP), CD133, and ${\beta}-catenin$; and formation of hDPCs 3D spheroids. Taken together, these data suggest that hUCB-MSCs promote hair growth via a paracrine mechanism.

THE EFFECT OF GROWTH FACTORS IN PLATELET-RICH PLASMA ON THE ACTIVITY OF OSTEOBLAST CELL LINE (혈소판농축혈장 내의 성장요소가 조골세포주의 활성도에 미치는 영향)

  • Jung Tae-Wook;Kim Yung-Soo;Kim Chang-Whe;Jang Kyung-Soo;Lim Young-Jun
    • The Journal of Korean Academy of Prosthodontics
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    • v.42 no.2
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    • pp.175-191
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    • 2004
  • Statement of problem: Platelet-rich plasma(PRP) is well known to be very effective method to stimulate and accelerate the healing of bone and soft tissue. However, there are few reports which deal with the mechanisms of the PRP on the activation of the osteoblasts. Purpose: This study was aimed to investigate the effect of growth factors in PRP on the activity of osteoblasts. Material and method: To evaluate the effect on human, human osteoblast cell line was cultured. PRP was extracted from the blood of a healthy volunteer. Using the recombinant growth factors of PDGF, $TGFT-\beta$, IGF-1, bFGF which are mainly found at bone matrix and their neutralizing antibody, the effect of PRP on the attachment and proliferation of osteoblasts was evaluated. To evaluate the autocrine and paracrine effects, conditioned media(CM) of PRP was made and compared with PRP. By the western blot analysis, the expression of growth factors in PRP, CM was examined. Cell morphology was compared by the light microscope. Results : 1) The effects of CM on osteoblast were similar to the effects of PRP. 2) PRP, CM, recombinant $TGF-\beta$, bFGF, IGF-1 showed significantly higher cellular attachment than control(p<0.05) in the cell attachment assay. In the cell proliferation assay, PRP, CM, recombinant $TGF-\beta$, IGF-1, bFGF, PDGF increased significantly cell proliferation(p<0.01). Among the recombinant growth factors, IGF-1 showed the highest cellular attachment and proliferation. 3) In the western blot assay, bFGF, IGF-1, PDGF weve equally expressed in PRP and CM. 4) The attachment of osteoblast cell decreased significantly after the addition of neutralizing antibody against $TGF-\beta$, IGF-1(p<0.05). In the cell proliferation assay, the addition of neutralizing antibody against $TGF-\beta$, bFGF, PDGF, IGF-1 decreased significantly the cellular proliferation(p<0.05). The amount of decreasing in the cell attachment and proliferation is the highest in at-lGF-1. 5) The cells in control group were flattened and elongated with a few cellular processes in the a light microscope. But, the cells appeared as spherical, plump cells with well developed cellular processes in experimental groups. The cells in PRP and CM had more prominent developed features than recombinant growth factor groups. Conclusions : These findings imply that PRP maximize the cellular activity in early healing period using the synergistic effect, autocrine, paracrine effects of growth factors and increase the rate and degree of bone formation.

Assessment of environmental impacts of LID technologies on vegetation

  • Choi, Hyeseon;Hong, Jungsun;Geronimo, F.K.F.;Kim, Lee-Hyung
    • Membrane and Water Treatment
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    • v.10 no.1
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    • pp.39-44
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    • 2019
  • LID facilities do not consider environmental factors, and due to inappropriate vegetation planting causing degradation in efficiency due to plant damage and difficulty in maintenance. Therefore, in this study, assessment of impact environmental factor by seasonal variation of chlorophyll and growth of vegetation planted in LID technologies and change of pollutant reduction were conducted. In the case of B-SJ and B-RI, growth rate decreased after summer (August), and B-MG showed steady growth until autumn (September). Chlorophyll was found to increase during spring season while it decreased during autumn season. The chlorophyll concentration was found to affect the plant growth pattern. TN reduction efficiency was highest with greater than 80% efficiency in summer, and it was analyzed that plants were identified as the main factor affecting the seasonal reduction efficiency of TN. Also, temperature and relative humidity were analyzed to affect plant growth, activity and pollutant removal efficiency. Plant type and growth pattern are considered as factors to be considered in selection of appropriate plant types in LID technologies.

Insulin-Like Growth Factors and Their Binding Proteins in Tumors and Ascites of Ovarian Cancer Patients: Association With Response To Neoadjuvant Chemotherapy

  • Yunusova, Natalia V;Villert, Alisa B;Spirina, Liudmila V;Frolova, Alena E;Kolomiets, Larisa A;Kondakova, Irina V
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.12
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    • pp.5315-5320
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    • 2016
  • Purpose: Tumor cell growth and sensitivity to chemotherapy depend on many factors, among which insulin-like growth factors (IGFs) may play important roles. The aim of the present study was to evaluate the levels of insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) in primary tumors and ascites as predictors of response to neoadjuvant chemotherapy in ovarian cancer (OC) patients. Materials and Methods: Tumor tissue samples and ascitic fluid were obtained from 59 patients with advanced OC. The levels of IGF-I, IGF-II, IGFBP-3, IGFBP-4 and PAPP-A were determined using ELISA kits. Taking into account the data on expression of these IGF-related proteins and outcome, logistic regression was performed to identify predictors of response to neoajuvant chemotherapy. Results: Human ovarian tumors expressed IGFs, IGFBP-3, IGFBP-4 and PAPP-A and these proteins were also present in ascites fluid and associated with its volume. IGFs and IGFBPs in ascites and soluble PAPP-A might play a key role in ovarian cancer progression. However, levels of proteins of the IGF system in tumors were not significant predictors of objective clinical response (oCR). Univariate analysis showed that the level of IGF-I in ascites was the only independent predictor for oCR. Conclusion: The level of IGF-I in ascites was shown to be an independent predictor of objective clinical response to chemotherapy for OC patients treated with neoadjuvant chemotherapy and debulking surgery.

Analysis of Health Status of Street Trees and Major Affecting Factors on Deogyeong-daero in Suwon (수원시 덕영대로의 가로수 건강성 평가 및 주요 영향요인 분석)

  • Kim, Eun-Young;Jung, Kyung-Min
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.2
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    • pp.49-57
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    • 2019
  • The street trees increase the liveability of cities by reducing stormwater runoff, improving air quality, storing carbon, providing shade, and ameliorating the urban heat-island effect. In this study, the health status of street trees in Suwon was evaluated, and the factors affecting the growth of the trees were also derived. In order to evaluate the growth and health of street trees, field survey was carried out on a total of 125 trees in 25 sections of the Deogyeong-daero where is through the city. During the field survey, the following items were examined: Street trees health status (i.e. species, height, DBH (diameter at breast height), planting types, vigor, etc.), soil factors (i.e. soil temperature, humidity, pH, hardness, etc.), and environmental factors (i.e. landuse, road width, etc.). As the results of field survey, the main species of the street trees was Zelkova serrata, which was healthy in most of the sections. The factors such as planting types, soil temperatures, tree root cover, road extension, distance from the road were derived to affect the growth and health of street trees, and the differences were significant. The results of this study were derived the following conclusions for vigorous street trees: First, it is important to install and maintain the protection facilities like tree root cover for the growth of trees. Second, it is necessary to discuss how to plant multiple trees in narrow spaces like a street green space. Third, it is important to provide appropriate soil conditions continuously for growth of threes. Finally, it should be utilized as a mitigation measure of urban heat island effects.

Development and Application of Village Extinction Index in Rural Areas - A Case Study on Chungcheongnam-do - (농촌의 마을소멸지수 개발 및 적용 - 충청남도를 대상으로 -)

  • Yun, Jeong-mi;Cho, Young-jae;Kim, Jin-young
    • Journal of Korean Society of Rural Planning
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    • v.29 no.3
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    • pp.15-24
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    • 2023
  • The sense of crisis regarding regional extinction due to low birth rates and an aging population is expanding. Generally, the local extinction index is used to analyze local extinction. However, it is challenging to diagnose the actual situation of village extinction risk in rural areas, even though the regional extinction index can be analyzed in units such as Si-Gun-Gu and Eup-Myeon-Dong. This difficulty arises because the regional extinction index solely relies on natural population growth indicators (elderly population and female population aged 20-39). Therefore, the purpose of this study is to develop a village extinction index that can identify the disappearance of rural villages. Additionally, the aim is to apply the developed indicators to the village (administrative ri) spatial unit. The existing regional extinction index used only mortality-related indicators as factors for natural population decline and fertility-related indicators as factors for natural population growth. However, the developed village extinction index included not only the factors of natural population change but also incorporated social population growth factors and factors related to the pace of village extinction. This is the key difference between the developed village extinction index and the existing regional extinction index. In this study, the indicators of "total population," "number of young women aged 20-44," "number of elderly population aged 70 or older," and "number of incoming population" were selected to develop a village extinction index. The village extinction index was developed by incorporating both natural population growth indicators and social population growth indicators. The developed village extinction index was applied to administrative villages. This research is expected to provide a more accurate understanding of the current state of rural villages facing extinction.