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Meta-analysis about the study related with foundation: As the center from 1998 to 2013 treatises (창업 관련 연구에 대한 메타분석: 1998년~2013년 학술지 논문을 중심으로)

  • Yoo, Jun Ho
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.1
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    • pp.51-67
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    • 2014
  • The study is aimed to recognize the meaning of foundation study through understanding history and flow of foundation study in Korea. The analysis period is from 1998 when there was first boom of venture foundation in Korea after IMF to 2013 September when the latest thesis was made, and the analysis intends total 382 dissertations the online. The analysis was conducted in the fields of foundation study, foundation support, foundation steps, founding company forms, founder's demographic features, and from the analysis, the following conclusion could be drawn out. First, the field actively carrying out foundation studies is the business management & economics field, but the foundation is dealt as an object of study across the all industries. It could be identified that of the all industries, especially IT industry, food service industry, and contents industry are the fields showing much interest about the foundation. Second, the field attracting most keen attention among the fields of foundation support was the field related with the founders. Third, the main problem relevant to foundation study was that the foundation was judged in comprehensive viewpoint, not being judged with strategies, in detail. Fourth, investing from the company's form aspect, it was found that during the starting period, the main foundation trend was the venture firm foundation, but recently the foundation-relevant attention is focused on the small business foundation and the most dominant founder type is the youth including college students, and the women's foundation is paid continual attention and senior foundation is being actively discussed. According to these analyzed results, future foundation studies should actively promote the general foundation studies, the specified foundation studies reflecting each industry's specialities, the fusion studies.

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Exploring the feasibility of Salmonella Typhimurium-specific phage as a novel bio-receptor

  • Choi, In Young;Park, Do Hyeon;Chin, Brayan A.;Lee, Cheonghoon;Lee, Jinyoung;Park, Mi-Kyung
    • Journal of Animal Science and Technology
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    • v.62 no.5
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    • pp.668-681
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    • 2020
  • The purpose of this study was aimed to isolate a Salmonella Typhimurium-specific phage (KFS-ST) from washing water in a poultry processing facility and to investigate the feasibility of the KFS-ST as a novel bio-receptor for the magnetoelastic (ME) biosensor method. KFS-ST against S. Typhimurium was isolated, propagated, and purified using a CsCl-gradient ultracentrifugation. Morphological characteristics of KFS-ST were analyzed using transmission electron microscopy (TEM). Its specificity and efficiency of plating analysis were conducted against 39 foodborne pathogens. The temperature and pH stabilities of KFS-ST were investigated by the exposure of the phage to various temperatures (-70℃-70℃) and pHs (1-12) for 1 h. A one-step growth curve analysis was performed to determine the eclipse time, latent time and burst size of phage. The storage stability of KFS-ST was studied by exposing KFS-ST to various storage temperatures (-70℃, -20℃, 4℃, and 22℃) for 12 weeks. KFS-ST was isolated and purified with a high concentration of (11.47 ± 0.25) Log PFU/mL. It had an icosahedral head (56.91 ± 2.90 nm) and a non-contractile tail (225.49 ± 2.67 nm), which was classified into the family of Siphoviridae in the order of Caudovirales. KFS-ST exhibited an excellent specificity against only S. Typhimurium and S. Enteritidis, which are considered two of the most problematic Salmonella strains in the meat and poultry. However, KFS-ST did not exhibit any specificity against six other Salmonella and 27 non-Salmonella strains. KFS-ST was stable at temperature of 4℃ to 50℃ and at pH of 4 to 12. The eclipse time, latent time, and burst size of KFS-ST were determined to be 10 min, 25 min and 26 PFU/ infected cell, respectively. KFS-ST was relatively stable during the 12-week storage period at all tested temperatures. Therefore, this study demonstrated the feasibility of KFS-ST as a novel bio-receptor for the detection of S. Typhimurium and S. Enteritidis in meat and poultry products using the ME biosensor method.

The Mineralogical and Chemical Characteristics of Slag from Kazakhstan and Leaching of Cu and Fe (카자흐스탄 구리 슬래그의 광물학적, 화학적 특성 및 구리와 철의 용출 특성)

  • Kim, Bong-Ju;Cho, Kang-Hee;Shin, Seung-Han;Choi, Nag-Choul;Park, Cheon-Young
    • Journal of the Mineralogical Society of Korea
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    • v.28 no.1
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    • pp.17-28
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    • 2015
  • In order to study the mineralogical and chemical characteristics of copper slag, optical microscopy, SEM/EDS, EPMA, AAS and XRD analyses were carried out. In addition, sulfuric acid leaching experiments were performed to investigate the potential of the slag as a copper resource. It was confirmed that fayalite, chromite, bornite and chalcopyrite were contained in the slag. The slag mainly consisted of acicular fayalite and skeletal lath -euhedral chromite crystals. Also a very large amount of bornite and chalcopyrite grains were contained in the slag. The content of Fe and Cu in the slag was 18.37% and 0.93%, respectively. As a result of sulfuric acid leaching experiments, the leaching rates of Cu and Fe were increased through decreasing the slag particle size, increasing the sulfuric acid concentration and the leaching temperature. The maximum efficiency of Cu and Fe leaching were obtained under the conditions of particle size of 32 mesh, sulfuric acid concentration of 2.0 M, and leaching temperature of $60^{\circ}C$. Accordingly, it is expected that the slag could be available as a potential and alternative resource of metallic copper.

Rainfastness of 5 Fungicides on the Leaf Surface of Hot Pepper (고추잎 표면에서 5종 살균제의 내우성)

  • Choi, Yun-Kyong;Yu, Ju-Hyun;Chun, Jae-Chul
    • Journal of Applied Biological Chemistry
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    • v.52 no.3
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    • pp.126-132
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    • 2009
  • In order to elucidate the relationship between the rainfastness of fungicides and their water solubilities, the fungicide residues on the leaf surface of hot pepper was assessed and compared after the drop-wise applications of fungicide solutions on leaf surface followed by artificial raining. As the raining was progressed after application of aqueous acetone solution of fungicides, the residue levels of fungicides were drop rapid at the early stage of raining, but the decreasing rates of residue level were slowed down thereafter. The initial rainfastness was reversely proportional to the water solubilities of the fungicides. Whole amount of dimethomorph residue, which water solubility is 18 mg/L, was washed off by 2.5 mm of raining. Although WP formulations of fungicides showed remarkable decreases of rainfastness compared to the aqueous acetone formulations, the fungicides having low water solubility showed better rainfastness. Chlorothalonil and mepanipyrim suspension concentrates was better in rainfastness than their WP formulation, and the rainfastness of mepanipyrim suspension was reversely proportional to the median diameter of suspension particles in the range of 1 to 4 ${\mu}m$. In brief, the rainfastness of 5 fungicides tested on the pepper leaf was, in the early stage of raining, closely related to water solubility. But, as the raining is progressed, the effect of the unknown factor, which is related with the particle size of fungicides, becomes serious.

Rapid HPLC Method for the Simultaneous Determination of Eight Urinary Metabolites of Toluene, Xylene and Styrene

  • Lee, Cheol-Woo;Lee, Jeong-Mi;Lee, Jae-Hyun;Eom, Han-Young;Kim, Min-Kyung;Suh, Joon-Hyuk;Yeom, Hye-Sun;Kim, Un-Yong;Youm, Jeong-Rok;Han, Sang-Beom
    • Bulletin of the Korean Chemical Society
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    • v.30 no.9
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    • pp.2021-2026
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    • 2009
  • Toluene, xylene and styrene are volatile organic solvents that are commonly used in mixtures in many industries. Because these solvents are metabolized and then excreted in urine, their urinary metabolites are thought to be biomarkers of occupational exposure to these solvents. Therefore, a simple, rapid, and yet reliable analytical method for determining the metabolites is required for accurate biological monitoring. In the present study, a simple and rapid HPLC-UV method was developed for the simultaneous determination of eight major metabolites of toluene, xylene and styrene: hippuric acid (HA), mandelic acid (MA), o-, m- and p-methylhippuric acids (o-, m- and p-MHAs), and o-, m- and p-cresols. A monolithic column was employed as the stationary phase and several conditions, including flow rate, composition of mobile phase and column temperature, were variables for the optimization of the chromatographic resolution. All eight metabolites were successfully resolved within 5 minutes in 10% aqueous ethanol containing 0.3% acetic acid and 1.6% $\beta$-cyclodextrin, using a flow rate gradient of 1.0 - 5.0 mL/min at 25 ${^{\circ}C}$. The performance of this method was validated by linearity, intra- and inter-day accuracy, and precision. The linearity was observed with correlation coefficients of 0.9998 for HA, 0.9999 for MA, 0.9989 for o-MHA, 0.9998 for m-MHA, 0.9991 for p-MHA, 0.9997 for o-cresol, 0.9998 for m-cresol, and 0.9986 for p-cresol. The intra- and inter-day precision of the method were less than 5.89% (CV) and the accuracy ranged from 92.95 to 106.62%. The validity was further confirmed by analysis of reference samples that were prepared by the inter-laboratory quality assurance program of the Korea Occupational Safety and Health Agency (KOSHA, Seoul, Korea). All measured concentrations of the analytes agreed with the certified values.

Temporal and Spatial Characteristics of Visual and Somatosensory Integration in Normal Adult Brain (정상성인의 시각 및 촉각 통합 작용 시 뇌신경세포의 전기생리적활동의 시간 및 공간적 특성: 예비실험)

  • Ju, Yu-Mi;Kim, Ji-Hyun
    • The Journal of Korean Academy of Sensory Integration
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    • v.8 no.1
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    • pp.41-49
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    • 2010
  • Objective : Multisensory integration (MSI) is the essential process to use diverse sensory information for cognitive task or execution of motor action. Especially, visual and somatosensory integration is critical for motor behavior and coordination. This study was designed to explain spatial and temporal characteristics of visual and somatosensory integration by neurophysiological research method that identifies the time course and brain location of the SI process. Methods : Electroencephalography (EEG) and event-related potential (ERP) is used in this study in order to observe neural activities when integrating visual and tactile input. We calculate the linear summation (SUM) of visual-related potentials (VEPs) and somatosensory-related potentials (SEPs), and compared the SUM with simultaneously presented visual-tactile ERPs(SIM) Results : There were significant differences between the SIM and SUM in later time epochs (about 200-300ms) at contralateral somatosensory areas (C4) and occipital cortices (O1&O2). The amplitude of the SIM was mathematically larger than the summed signals, implying that the integration made some extra neural activities. Conclusion : This study provides some empirical neural evidence of that multisensory integration is more powerful than just combing two unisensory inputs in the brain and ERP data reveals neural signature relating to multisensory integrative process. Since this study is preliminary pilot study, larger population and criteria are needed for level of the significance. Further study is recommended to consider issues including effect of internally-driven attention and laterality of interaction to make the evidence by this study solid.

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The effect of call center agent job characteristics on turnover intention : focused on moderating effect of self leadership (콜센터 상담직원의 직무특성이 이직의도에 미치는 영향 : 셀프리더십의 조절효과를 중심으로)

  • Oh, Jong-chul;An, Un-seok
    • Journal of Venture Innovation
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    • v.1 no.1
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    • pp.145-164
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    • 2018
  • The purposes of this study was to investigate job related attitudes of emotional labors working at call centers in Korea. The attitudinal variables were burnout, psychological capital and turnover intention with job characteristics as the independent variables. In addition, leadership behaviors of the superiors, self leadership behavior in particular, was incorporated to see if it has any bearing on these relationship as moderating variable. Data has been collected from 543 respondents for this study using questionnaire method. The survey for the actual analysis of the research was done and analyzed with the employees who work for contact centers in Seoul, Busan, and Gwangju, Korea. The survey was done for 24 days from November, 2016 through December, 2016. * The following study results were revealed: First, the job characteristics does not have direct positive effect on turnover intentions. Second, the job characteristics were related positively to job burnout. Third, the job burnout does mediate the relationship between job characteristics and turnover intentions. Lastly, results of research on the moderating effect of self leadership in relationships between emotional labor, job burnout, psychological capital and turnover intention show that super leadership has only a limited regulatory effect between job characteristics and turnover intention.

Computation of Aeolian Tones from Twin-Cylinders Using Immersed Surface Dipole Sources

  • Cheong, Cheol-Ung;Ryu, Je-Wook;Lee, Soo-Gab
    • Journal of Mechanical Science and Technology
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    • v.20 no.12
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    • pp.2292-2314
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    • 2006
  • Efficient numerical method is developed for the prediction of aerodynamic noise generation and propagation in low Mach number flows such as aeolian tone noise. The proposed numerical method is based on acoustic/viscous splitting techniques of which acoustic solvers use simplified linearised Euler equations, full linearised Euler equations and nonlinear perturbation equations as acoustic governing equations. All of acoustic equations are forced with immersed surface dipole model which is developed for the efficient computation of aerodynamic noise generation and propagation in low Mach number flows in which dipole source, originating from unsteady pressure fluctuation on a solid surface, is known to be more efficient than quadrupole sources. Multi-scale overset grid technique is also utilized to resolve the complex geometries. Initially, aeolian tone from single cylinder is considered to examine the effects that the immersed surface dipole models combined with the different acoustic governing equations have on the overall accuracy of the method. Then, the current numerical method is applied to the simulation of the aeolian tones from twin cylinders aligned perpendicularly to the mean flow and separated 3 diameters between their centers. In this configuration, symmetric vortices are shed from twin cylinders, which leads to the anti-phase of the lift dipoles and the in-phase of the drag dipoles. Due to these phase differences, the directivity of the fluctuating pressure from the lift dipoles shows the comparable magnitude with that from the drag dipoles at 10 diameters apart from the origin. However, the directivity at 100 diameters shows that the lift-dipole originated noise has larger magnitude than, but still comparable to, that of the drag-dipole one. Comparison of the numerical results with and without mean flow effects on the acoustic wave emphasizes the effects of the sheared background flows around the cylinders on the propagating acoustic waves, which is not generally considered by the classic acoustic analogy methods. Through the comparison of the results using the immersed surface dipole models with those using point sources, it is demonstrated that the current methods can allow for the complex interactions between the acoustic wave and the solid wall and the effects of the mean flow on the acoustic waves.

Experimental Study on the Hydrodynamic Dispersion of Contaminants in Geologic Media : Adsorption and Diffusion of Sr and Cr-EDTA in Granitic Rocks (수리지질계에서 지질매체에 따른 오염물질의 수리분산에 관한 실험적 연구 : 화강암질암에서 Sr과 Cr-EDTA의 흡착 및 확산에 관한 연구)

  • Chang, Ho-Wan;Lee, Kwang-Sik
    • Journal of the Korean Society of Groundwater Environment
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    • v.1 no.2
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    • pp.105-112
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    • 1994
  • To investigate the migration behavior of contaminants in rocks. adsorption and diffusion experiments for Sr as a sorbing contaminant and for Cr-EDTA as a non-sorbing contaminant were carried out on granitic rocks. The Sr adsorption on separated minerals and crushed rocks tends to slightly increase with increasing pH. It also greatly decreases with the increase of ionic strength in NaCl solution. Among separated minerals, biotite and sericite have adsorbed much more amount of Sr than other rock-forming minerals, such as quartz, plagioclase, and potassic feldspar, because the specific surfaces and cation exchange capacities of phyllosilicates are generally much greater than those of the other rock-forming minerals. The intrinsic diffusion coefficients of Cr-EBTA for granitic rocks differ little from those of Sr. This indicates that they are independent of water-rock interactions. Experimental data show that the intrinsic diffusion coefficients are positively correlated with the porosities of the rocks. They are close to the theoretically predicted values, especially in pre-steady state diffusion region, with the increase of rock sample thickness.

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Species of Korean Furniture in the Late Choseon Dynasty (I)

  • Song, Ji-Ae;Park, Won-Kyu
    • Journal of the Korea Furniture Society
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    • v.21 no.6
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    • pp.486-498
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    • 2010
  • The purpose of this study was to analyze the species of 82 furniture in the late Choseon Dynasty (mainly, 19th century), which are housed in the Seoul Museum of History. Total of 22 species were found. The species shared 43% as hard pine(Diploxylon), 9% as Zelkova serrata Makino, 7% as Paulownia spp., 7% as Tilia spp., 6% as soft pine(Haploxylon), 5% as Ginkgo biloba Linn., 4% as Cedrela sinensis A. Juss., 3% as Diospyros spp., 3% as Abies spp., 2% as Alnus spp., 2% as Picea spp., 1% as bamboo, 1% as Populus spp., 1% as Betula spp., 1% as Juglans spp. The other minor ones were Torreya nucifera Sieb. et Zucc., Pyrus spp., Castanea spp., Ulmus spp. and Kalopanax oictuse (Thunb.) Nakai. Thirty seven furniture (45% in total) was made of single species, 19 (23%) of two species, 16 (20%) of three species and 10(12%) of 4 to 6 species. For frames and panels, hard and strong woods, such as hard pines, Zelkova and Cedrela, were used. For drawer, however, light woods having low shrinkage, such as Paulownia and Tilia, were used. The origin of woods could be specified by the habitats of the species identified. Both Hwanghaedo- and Parkcheon- Chests used basswood (Tilia), which grow in the cold regions, indicating the origin of woods as North Korea.

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