• Title/Summary/Keyword: environment effect

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Analysis of Factors Influencing Entrepreneurial Performance at the University Level for Becoming Entrepreneurial Universities (기업가형 대학(Entrepreneurial University)을 위한 대학의 창업 성과 영향요인 분석)

  • Lim, Hanryeo;Hon, Sungpyo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.2
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    • pp.19-32
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    • 2020
  • The purpose of this study was to investigate the influence factors of the university level centering on the entrepreneurial performance of the university students and full-time faculties in the situation of increasing interest in entrepreneurial university. In order to achieve the purpose of the study, a panel data was established from 2015 to 2018 on the basis of the university notification data. The panel data included universities with data on the number of university students and full-time faculty founders for at least two years. Through this, four year data from 154 universities were used for analysis. As an analysis method, frequency analysis and descriptive statistics were conducted to understand the characteristics of the university. Since then, panel negative binomial regression analysis has been conducted in consideration of the longitudinal features and distribution of the data. Also, based on the Hausman test results, the results were interpreted based on random effect model. The results of this study are as follows. First, as a result of the analysis of the entrepreneurial performance and the change trend of the domestic university from 2015 to 2018, the entrepreneurial performance of the university has been steadily increasing in the last four years, and the increase in the number of university student entrepreneurs was relatively higher than the full-time faculties. Second, economic and educational approaches need to be combined to promote university students' start-ups. The university factors that promote the start-up of university students were found to be scholarships, start-up grants, startup lectures, and startup clubs. Third, the openness and regional characteristics of the univeristy can promote the establishment of university students. Fourth, the establishment of a research environment and support for start-ups for full-time faculty members can enhance their start-up performance. The university factors that promote the start-up of full-time faculty were research funds and staffes who support start-up. The conclusions drawn from these findings are as follows. First, overall efforts are needed to develop into an entrepreneurial university. Second, in order to change into an entrepreneurial university, direct support for entrepreneurship is needed. Third, as an entrepreneurial university, it is necessary to find a way to bridge the gap by university according to region and size. Fourth, it is necessary to reinforce the support for linking the research results of universities to start-ups. Fifth, it is necessary to improve the atmosphere for full-time faculty members to be entrepreneur.

Differences of Wood Vinegar Ingestion and Exercise Training on Blood Lipids, MDA, and SOD Activities in Rats (4주간 흰쥐의 목초액 섭취와 운동에 따른 혈중지질과 MDA, SOD 활성 차이)

  • Kang, Jong-Suk;Kim, Sea-Hyun;Kim, Pan-Gi;Lee, Dong-Woon;Ryu, Sung-Pil
    • Journal of Life Science
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    • v.19 no.9
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    • pp.1190-1199
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    • 2009
  • The purpose of this study is to identify the effects of exercise training and oak tree wood vinegar ingestion on the blood lipids and antioxidant activities of rats. The subjects were 28 Sprague Dawley male rats, and they were assigned into four groups (n=7, respectively): the control group (CON), the exercise group (EXE), the vinegar ingestion group (VIN), and the vinegar ingestion and exercise training group (VINEXE). The diet was based on high fat and oral administration of oak tree wood vinegar. The rats that were not given oak tree wood vinegar were given the same amount of distilled water orally in order to maintain the same level of stress. They were exercise trained on motor-driven treadmills during a four-week session. Weight changes in the VINEXE were significantly inhibited in the later period of exercise, when compared to the CON (p<0.05). Fat increase was significantly suppressed in VIN and EXE (p<0.05), and a synergistic effect was discovered in the VINEXE (p<0.05). Glucose and ammonia levels were significantly reduced in the EXE, VIN, and VINEXE compared to the CON (p<0.05). In blood lipids, TC and LDL-C were significantly enhanced in the EXE, VIN, and VINEXE compared to the CON (p<0.05), while HDL-C was significantly improved in the EXE and VINEXE (p<0.05). Liver MDA contents showed significant changes in each group (p<0.05), and SOD activities were significantly enhanced in the VIN and the VINEXE when compared to other groups (p<0.05). Therefore, oak tree wood vinegar ingestion with exercise training for four weeks may result in inhibition of weight gain, improvement of blood lipids, and inhibition of lipid peroxidation, contributing to health promotion.

Effect of Dietary Probiotics Supplementation Contained with Astaxanthin Produced by Phaffia rhodozyma on the Productivity and Meat Quality of Ducks (Astaxanthin을 생성하는 Phaffia rhodozyma를 포함한 미생물제제의 급여가 오리의 성장과 육질에 미치는 영향)

  • Kim K. S.;Lee J. H.;Shin M. S.;Cho M. S.;Kim Y. P.;Cho S. K.;Kang Y. J.
    • Korean Journal of Poultry Science
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    • v.32 no.2
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    • pp.73-80
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    • 2005
  • This study was carried out to investigate the influence of dietary probiotics supplementation contained with astaxanthin synthesizing microorganism 'Phaffia rhodozyma' on the productivity and meat quality of ducks. Growth performance carried out during 45 days for day-old ducks offered in Joowonori incorporated. A total of 150 day-old ducks(cheribery) of mixed sex(M:F=1:1) were allotted into 5 groups. The basal diets were added with low levels of astaxanthin containing probiotics. We investigated mortality, bodyweight, and feed conversion used by growth performance. 45day-old ducks were butchered and carried out nutrients composition analysis, meat quality test, organoleptic examination, fatty acid analysis, cholesterol analysis, storage test, and astaxanthin concentration analysis. Control showed $3.7\%$ mortality and treatments showed $0\%$ mortality. These results showed improvement of immunity, for influence of dietary probiotics supplementation contained with astaxanthin. The control gained 2.68 kg and treatment gained 2.84 kg. The control was 2.15 and treatment was 1.83 for feed conversion. Treatment was increased feed conversion than control as significantly. The results of meat quality test showed that treatment was tender and taste more than control. The results of nutrients composition analysis showed that treatment was produced low fat and high protein meat. Ducks meat of treatments contained higher unsaturated fatty acid and lower cholesterol than control. The case of carotenoids confirmed that astaxanthin and $\beta-carotein$ were accumulated in duck meat.

Structure and Variation of Tidal Flat Temperature in Gomso Bay, West Coast of Korea (서해안 곰소만 갯벌 온도의 구조 및 변화)

  • Lee, Sang-Ho;Cho, Yang-Ki;You, Kwang-Woo;Kim, Young-Gon;Choi, Hyun-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.100-112
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    • 2005
  • Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

Photoalteration in Biodegradability and Chemical Compositions of Algae- derived Dissolved Organic Matter (자외선에 의한 조류기원 용존유기물의 생분해도 및 화학조성변환.)

  • Imai, Akio;Matsushige, Kazuo;Nagai, Takashi;Kim, Yong-Hwan;Kim, Bom-Chul;Choi, Kwang-Soon
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.235-241
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    • 2003
  • The effect of ultraviolet (UV) radiation on the characteristics of algae-derived dissolved organic matter (DOM) was examined by comparing the biodegradability and DOM fraction distribution of algal DOM before and after UV exposure. Algal DOM from two axenic cultures of Microcystis aeruginosa and Oscillatoria agardhii were irradiated for 24 h at a UV intensity of 42 W/$m^2$. A complete degradation of algal DOM during the UV exposure did not occur, remaining at constant concentrations of dissolved organic carbon(DOC). After UV exposure, however, microbial degradations were reduced by 17% in M. aeruginosa and 53% in O. agardhii, respectively, and decomposition rates also were two times lower in UV exposed algal DOM. In addition, the chemical compositions of algal DOM altered substantially after UV radiation exposure. The proportions of hydrophilic bases (HiB; protein-like DOM) decreased considerably in both algal DOM sources after UV exposure (16.8% and 20.0% of DOM, respectively), whereas those of hydrophilic acids (HiA; carboxylic acids-like DOM) increased as much as the decrease of the HiB fraction. Capillary ion electrophoresis (CE) analysis showed that several carboxylic acids increased significantly after UV exposure, further confirming an increase in HiA fractions. The results of this study clearly indicate that algal DOM can be changed in its chemical composition as well as biodegradability without complete degradation by UV radiation.

SOD and Inorganic Nutrient Fluxes from Sediment in the Downstream of the Nagdong River (낙동강 하류 수계에서 저질퇴적층의 SOD와 영양염 용출)

  • Jung, Ha-Young;Cho, Kyung-Je
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.322-335
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    • 2003
  • Nutrient fluxes and sediment oxygen demands (SOD) were measured with intact sediment cores collected from three stations in the downstream of Nagdong River. The sediments were subjected to controlled oxic and hypoxic conditions and temperature gradients (from $10^{\circ}C$ to $30^{\circ}C$) of the overlying waters in laboratory batch system. The effect of temperature and labile layer thickness of the sediment on SOD were examined. $PO_4\;^{3-}$ and $NH_4\;^+$ fluxes were elevated above $20^{\circ}C$ and large mobilities were observed when they were coupled with a hypoxic and high-temperature condition. In the well oxygenated conditions, $PO_4\;^{3-}$ fluxes were negative or negligible but $NH_4\;^+$ fluxes ranged from 1.3 mg N $m^{-2}\;hr^{-1}$ to 2.3 $m^{-2}\;hr^{-1}$. Temperature quotients($Q_{10}$) of $PO_4\;^{3-}$ fluxes were 3.7 ${\sim}$ 7.3 ranges to have the most high values. $PO_4\;^{3-}$ and $NH_4\;^+$ fluxes had the logarithmic increase with temperature, while $NO_3\;^-$ was negatively absorbed to the sediment and linearly correlated with the temperature. $SiO_2$ fluxes showed no difference among oxic and hypoxic conditions and sediment texture. The nutrient fluxes would be closely correlated with pore water chemistry of sediments and activated by the top sediment layer composition such as labile organic matters or algal detritus. The ecological implications of the nutrient fluxes were discussed in terms of sources and sinks of nutrients coupled to algal productions in the Nagdong River.

Distribution Model of the Wintering Red-crowned Crane and White-naped Crane in Cheorwon, Korea (철원지역에서 월동하는 두루미와 재두루미의 서식밀도모델)

  • Yoo, Seung-Hwa;Lee, Ki-Sup;Kim, Hwa-Jung;Hur, Wee-Haeng;Kim, Jin-Han;Park, Chong-Hwa
    • Korean Journal of Ecology and Environment
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    • v.47 no.4
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    • pp.282-291
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    • 2014
  • This study was conducted to make distribution model of the Red-crowned Crane and the White-naped Crane according to the anthropogenic and natural factors affecting distribution of crane in Cheorwon, Korea. It was investigated that the impact power and its range of the indirect anthropogenic influence to feeding flock density in cranes from the road, residential area, military facilities, civilian control zone (CCZ), greenhouse and natural influence such as roosting site and available feeding area. Available feeding area is the most important factor for the crane's feeding site selection. The feeding flock density of the cranes near the residential area was lower than that of area far from the area, and tended to increase within 2.5 km distance. The increasing tendencies of feeding flock density from military facilities and high traffic volume road were similar, but the density in military facilities increased within 800 m, and the density from high traffic volume road increased within 2 km. These results suggested that residential area, military facilities and the road with high traffic volume had significant effect on foraging densities to the certain range. As the distance from the road with low traffic volume and roosting site increased, feeding flock density tended to decrease. The density of Red-crowned crane and White-naped crane inside the CCZ were respectively higher than those of outside the CCZ, especially for the Red-crowned crane. As a result, density of Red crowned cranes inside the CCZ was 5.2 times higher than that of outside, while that of white-naped cranes was 2.2 times bigger. If the density of greenhouse is lower than $40km^{-2}$, crane's feeding flock density in the low greenhouses density area was higher than that of high greenhouses density area. However, there was no difference in the feeding flock density if the density of the green houses is higher than $40km^{-2}$. The model for the Red-crowned Crane was related with available feeding area, distance from residential area, civilian control zone and distance from high traffic road. The model of the White-naped Crane was related with available feeding area, distance from roosting site and distance from lake. Finally, the estimated feeding flock density of cranes significantly correlated with density model according to the natural and anthropogenic factors.

Relation of Stream Shape Complexity to Land Use, Water Quality and Benthic Diatoms in the Seom River Watershed (섬강 수계에서 하천 형태복잡도와 토지이용, 수질 및 부착규조류 군집 분포와의 관계)

  • Min, Han-Na;Kim, Nan-Young;Kim, Mi-Kyung;Lee, Sang-Woo;Hwang, Kil-Soon;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.45 no.1
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    • pp.110-122
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    • 2012
  • This study examined the benthic diatom community distribution, land cover/use and water quality in relation to stream shape complexity (SSC) in the Seom River watershed. SSC showed a significant relation to the riparian land cover/use pattern and also water quality variables of the studied streams. Streams with high stream shape complexity (HSC) appeared to have a high proportion of forest and farmland, while streams having a low stream shape complexity (LSC) appeared to have high proportion of city. Streams with lower SSC showed higher nutrients concentration in the stream waters. Benthic diatom species composition and dominant species appeared to be similar regardless of SSC differences among the studied streams, while the variation of diatom density was manifested with SSC. The relative abundance of dominant benthic diatoms varied with SSC. Saprophilic diatoms were dominant in the streams of LSC, while saproxenic diatoms were dominant in the streams of HSC. During the evaluation of biological water quality using the benthic diatom indices, Trophic Diatom Index (TDI) and Diatom Assemblage Index to organic water pollution (DAIpo), the streams of LSC generally showed poorer water quality than those of MSC (Middle stream shape complexity) and HSC. In particular, BOD, TP, and $PO_4$-P showed significant relationships with DAIpo. In conclusion, shape complexity of streams in the Seom River watershed showed a close relation with benthic diatom distribution. This relation seemed to primarily be resulted from the effect of proximate factors, such as water quality, which might be affected by the land use types determining the degree of SSC.

The Effect of Hydrology on Phytoplankton Assemblages and Its Adaptive Strategies in Lake Hwaseong, Estuarine Reservoir with Seawater Exchange, Korea (해수유통 중인 간척담수호 화성호에서 식물플랑크톤의 군집과 적응전략에 대한 수문학적 영향)

  • Song, Tae Yoon;Yoo, Man Ho;Lee, In Ho;Kang, Eue-Tae;Kim, Mi Ok;Choi, Joong Ki
    • Korean Journal of Ecology and Environment
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    • v.47 no.2
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    • pp.71-81
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    • 2014
  • A survey was carried out to understand the influence of hydrology on the composition, abundance and adaptive strategies of phytoplankton in artificial Lake Hwaseong, an estuarine reservoir with seawater exchange through a sluice. Samples were collected seven times from May to October 2012. Hydrological events (seawater exchange, rainfall) resulted in a wide variation in salinity along with nutrients and turbidity. Shifts in the dominant phytoplankton composition occurred on every survey. Chlorophyll-a ranged from 9.7 to $104.1{\mu}g\;L^{-1}$. Multivariate analysis allowed us to identify the four phases on phytoplankton community change. Phase I (May~June) was characterized by small-sized Gymnodinium sp. and Heterosigma akashiwo dominated in warm temperature and high salinity derived from seawater exchange, and followed by Cylindrotheca closterium blooms due to rainfall and winds during phase II (July and September). During phase III (August), the dominance of Oscillatoria spp. was correlated with high temperature and low salinity. Abundant cryptomonads were associated with lower temperature during phase IV (October). Adaptive strategies were identified in the phytoplankton as morphological and physiological characteristics. These strategies identified small-sized flagellates as CR-strategists, fast-growing opportunistic species, which might favor the weak stratification of lake due to the seawater exchange during phase I and IV. Dominant species during phase II and III were characterized with R-strategists, medium-sized stress-tolerant species, which might favor turbulence by river flow. The results indicate that stronger stratification following the termination of seawater exchange for the freshening might intensify the predominance of smaller flagellates. In conclusion, this study suggests that hydrology may drive phytoplankton community change and blooms through the controls of salinity, turbulence and nutrients.

Phytoplankton Community Change of Lake Paldang by Increasing $CO_2$ and Temperature during Spring Cold Water Season ($CO_2$와 수온 증가에 대한 봄철 저수온기 팔당호 식물플랑크톤군집 변화)

  • Lee, Ka-Ram;Sung, Eun-Ju;Park, Hye-Jin;Park, Chae-Hong;Park, Myung-Hwan;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.46 no.4
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    • pp.588-595
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    • 2013
  • This study investigated the influence of temperature and $CO_2$ increase on phytoplankton growth and community structure during cold water season (spring) in Lake Paldang, Korea. Four experimental treatments of temperature and $CO_2$ manipulation were prepared in the laboratory batch culture: (1) Control; ambient low temperature ($6{\pm}2^{\circ}C$) and low $CO_2$ (air level, $400mgL^{-1}$), (2) T1; low temperature and high $CO_2$ ($800mgL^{-1}$), (3) T2; high temperature ($20{\pm}2^{\circ}C$) and low $CO_2$, (4) T3; high temperature and high $CO_2$. Algal growth experiment was carried out for 10 days under the light intensity of $70{\mu}mol\;m^{-2}s^{-1}$ (L :D=24 : 0). The level of pH decreased in both T1 and T3, due to dissolution of added $CO_2$. The dominant phytoplankton species of ambient water, Cyclotella meneghiniana succeeded to Fragilaria capucina var. gracilis in high-temperature treatment groups (T2 and T3). Cyanobacteria were very rare at the beginning of the experiment, while Oscillatoria limnetica appeared in only high-temperature groups (T2 and T3) at $6{\sim}7^{th}$ day. $CO_2$ addition in ambient temperature (T1) induced the highest phytoplankton growth, and thereby producing the highest average cell density of $3.27{\pm}0.33\;10^4\;cells\;mL^{-1}$, followed by T2 ($2.65{\pm}0.26\;10^4\;cells\;mL^{-1}$), T3 ($2.09{\pm}0.16\;10^4\;cells\;mL^{-1}$), and Control ($1.86{\pm}0.13\;10^4\;cells\;mL^{-1}$) (F=7.167, p=0.000). In summary, temperature increase changed the phytoplankton community structure and $CO_2$ increase promoted the phytoplankton growth during the cold spring season in Lake Paldang, suggesting a potential effect of climate change on freshwater phytoplankton.