• Journal of the Korean Magnetic Resonance Society
• /
• v.24 no.2
• /
• pp.53-58
• /
• 2020

Free radicals including reactive oxygen species (ROS) are important chemicals in the research area of biology, pharmaceutical, medical, and environmental science as well as human health risk assessment as they are highly involved in diverse metabolism and toxicity mechanisms through chemical reactions with various components of living bodies. Electron spin resonance (ESR) spectroscopy is a powerful tool for detecting and quantifying those radicals in biological environments. In this work we observed the ESR signal of 2,2,6,6-Tetra-methyl piperidine 1-oxyl (TEMPO) in aqueous solution at various concentrations to estimate the uncertainty factors arising from the experimental conditions and signal treatment methods. As the sample position highly influences the signal intensity, dual ESR tube geometry (consists of a detachable sample tube and a position fixed external tube) was adopted. This type of measurement geometry allowed to get the relative uncertainty of signal intensity lower than 1% when triple measurements are averaged. Linear dependence of signal intensity on the TEMPO concentration, which is required for the quantification of unknown sample, could be obtained over a concentration range of ~10³ by optimizing the signal treatment method depending on the concentration range.

• International Commerce and Information Review
• /
• v.11 no.1
• /
• pp.485-515
• /
• 2009

In this study aims to research and analyze what are decision factors between a wholly-owned subsidiary and a international company cooperation in the internationalization process. From 57 primary studies found 26 observed variables for aggregation of effect size in the using "Fixed Effect Model" on this mata-analysis. The article also links the theories that are used in the literature, not considered in the most of primary studies, to the empirical results and recommends global management strategy which is needed for business practical affairs. According to the result, the meta-analysis suggests that the number of employees of a MNC, the geological and cultural differneces between the host country and home country, the country-specific international experience of the MNC and export intensity, the international product diversification, the market growth and the market size of the foreign operations, and resource intensity of the foreign operations, the legal restrictions in the host country and the country risk of the home country do exert a significant effect on the decision between cooperative arrangement and a wholly-owned subsidiary. Conversely, for a large number of variables, no significant relationship seems to exist based on the combined results. This is the case, for example, for factor specificity, the r&d-intensity, the subsidiary size, the assets of the MNC and the sales volume of the MNC.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07a
• /
• pp.175-178
• /
• 2005

The spatio-temporal behaviors of Infra Red(IR) emission images of the sustain discharges were observed in AC PDP with various coplanar-gaps and auxiliary electrode. When the height of barrier rib was fixed, IR intensity of the sustain discharges in AC PDP did not increase with increase of coplanar-gap. The IR efficiency of sustain discharges showed the similar behavior with the IR intensity. The IR intensity had its maixmum value when the coplanar-gap was $200\;{\mu}m$ and the height of barrier rib was $150\;{\mu}m$. It was also found that the auxiliary electrode in the front plate enhanced IR emission during sustain discharge when the pulse was applied to the auxiliary electrode.

• The Bulletin of The Korean Astronomical Society
• /
• v.38 no.1
• /
• pp.66.2-66.2
• /
• 2013

In this study, we present a pore-selection technique to estimate the size of pore. The estimation of the size of pore is important to examine the temporal evolution of size itself and corresponding intensity. The size of pore is typically estimated by applying the intensity threshold technique to the fixed box which contains the entire pore. The typical method has disadvantages in the following circumstances; there are small features near the pore or the image has low spatial resolution. In the former, it is difficult to define a box containing the pore only, excluding the small features near the pore. In the latter, the background and threshold intensity are insignificant due to the insufficient number of pixel in the box. To avoid these difficulties, we use a pore-selection technique which is simply based on the measurement of distances from the pore center. In addition, we will discuss the advantage of the technique for the imaging spectrograph data like the NST FISS.

• East Asian Economic Review
• /
• v.18 no.1
• /
• pp.29-54
• /
• 2014

The purpose of this research is to identify the relation between OFDI (Outward Foreign Direct Investment) and wage inequality. In order to analyze various effects of OFDI on wages depending on the types of workers, the research classified laborers into four categories: permanent/skilled worker, permanent/unskilled worker, temporary/skilled worker, and temporary/unskilled worker. With controlling wage-determining factors such as education, labor union, individual fixed-effect, and industry-level effect, this paper examines whether OFDI attributes to the wage inequality among each type of workers. Moreover, this study also analyzes possible effects on wages that could vary according to the different characteristics of investments by classifying OFDI into two groups: OECD and non-OECD. The results reveal that OFDI makes certain differences according to skill-intensity and contract type in terms of influences on wages. It also shows that the effect of OFDI on wages is more subject to contract type than to skill-intensity. The classification of OFDI into OECD and non-OECD proves that effects on wages can vary by characteristics of the subject of investment.

• Journal of fish pathology
• /
• v.34 no.2
• /
• pp.169-176
• /
• 2021

Parasitic infection is among the most common problems for carp cultivation. They are also important for the principal entrance of other hazardous infections as well. This study was carried out for determining of parasitic fauna of two major carp known as silver and grass carp with the comparison of prevalence value and intensity rate of parasites among them, alongside the relationship between the biometric characteristics and host sex with the infection level. For this purpose, a total of 94 fish samples were caught randomly using a fishing net, from Guilan ponds during spring and summer of the year 2018 and transported alive to the laboratory. Upon arriving, the biometric characteristics and genus of each carp were measured individually. Specimens were then acquired from the skin, gills, and eyes of the carp and examined according to standard parasitology methods. Recovered parasites were observed under a light microscope and then fixed for identification. As the result, the occurrence and intensity in the higher length group were comparatively greater than the lower one. Also, the prevalence and intensity of total parasites in male carp were higher than in females. In this research, Dactylogyrus hypophthalmichthys and Dactylogyrus aristhichtys were observed in silver carp and Dactylogyrus lamellatus was detected in grass carp. In the paper below, we found that the host specificity varies in different species of Dactylogyrus isolated from grass carp and silver carp.

• Korea Trade Review
• /
• v.46 no.2
• /
• pp.75-92
• /
• 2021

There is increasing awareness in the international alliance literature that the firm performance effects of the alliance portfolio go beyond the effects of the individual alliances. I enrich this nascent perspective by developing a alliance portfolio composition framework based on the alliance portfolio dimensions - underpinned by the simultaneity of quantitative and qualitative factors in international portfolio - that enhances firms' financial performance. This paper assesses the impact on firm performance of composing the alliance dimension within a firm's international alliance portfolio. In an unbalanced panel data analysis with fixed effects of the performance of 502 firms operating in the Korean manufacturing industry during 2011-2017, I test whether firm's three dimension of international alliance portfolio affect on firm financial performance. I find that the intensity of international alliance have significantly positive effect on the firm performance. And following the moderating analysis of three portfolio dimension-functional, relational, and attribute, all of each three international alliance portfolio has positive moderating effects on the relationship between the alliance intensity and firm performance. These results indicate that firms should consider and form simultaneous approaches to exploit the international alliance based on the alliance portfolio dimensions with intensity of alliance portfolio.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.18 no.9
• /
• pp.2331-2338
• /
• 1994

Experimental conditions of the optical shadow methods of caustics for measurement of the stress intensity factor and the J-integral in various materials(polycarbonate, PMMA, Al 5586D) are investigated. The necessary experimental requirements toe determine accurate values of the stress intensity factors and the J-integrals are described. The ratio of $r_o$ (radius of initial curve) to $r_p$ (plastic zone size) is selected as a parameter to verify the experimental limitation of the method of caustics in determination of fracture parameters. In this study, transmission caustics method was used for compact tension specimens made of polycarbonate and PMMA. while reflection caustics method was applied to c-shaped tension specimen made of Al 5586D. The appropriate ranges of $r_o/r_p$ tp determine accurate values of stress intensity factors were found to be 1.5~1.8. Existing experimental results have been obtained mainly by changing $r_p$ with different loads in $r_o/r_p$. However, in this study we could obtain varying $K_{caus}/K_{th}$ over the wide range of $r_o/r_p$ at fixed load conditions with newly designed optical arrangement. Thus, we could find the range in which theoretical and experimental results agree well each other by changing $r_o$ values only. In Al 5586D specimen, experimental caustics were located inside of the plastic zone, and $K_{caus}/K_{th}$ were found to be not unity in this range. It is found that $J_{caus}/J_{th}=1{\;}with{\;}r_o/t{\geq}0.8$ and the experimental plastic zone includes the contours of caustics.

• Communications for Statistical Applications and Methods
• /
• v.30 no.1
• /
• pp.95-107
• /
• 2023

Purpose: The statistical analysis of point processes on linear networks is a recent area of research that studies processes of events happening randomly in space (or space-time) but with locations limited to reside on a linear network. For example, traffic accidents happen at random places that are limited to lying on a network of streets. This paper applies techniques developed for point processes on linear networks and the tools available in the R-package spatstat to estimate the intensity of traffic accidents in Leon County, Florida. Methods: The intensity of accidents on the linear network of streets is estimated using log-linear Poisson models which incorporate cubic basis spline (B-spline) terms which are functions of the x and y coordinates. The splines used equally-spaced knots. Ten different models are fit to the data using a variety of covariates. The models are compared with each other using an analysis of deviance for nested models. Results: We found all covariates contributed significantly to the model. AIC and BIC were used to select 9 as the number of knots. Additionally, covariates have different effects such as increasing the speed limit would decrease traffic accident intensity by 0.9794 but increasing the number of lanes would result in an increase in the intensity of traffic accidents by 1.086. Conclusion: Our analysis shows that if other conditions are held fixed, the number of accidents actually decreases on roads with higher speed limits. The software we currently use allows our models to contain only spatial covariates and does not permit the use of temporal or space-time covariates. We would like to extend our models to include such covariates which would allow us to include weather conditions or the presence of special events (football games or concerts) as covariates.

• Journal of Korean Institute of Industrial Engineers
• /
• v.22 no.1
• /
• pp.83-93
• /
• 1996

In this research, we concentrate on the effects of dependencies in arrival processes on queueing measures. In particular, we use a specific form of arrival process which has the advantage of allowing us to change dependency properties without at the same time changing one dimensional distributional conditions. It is shown that the mean queue length can be made arbitrarily large with the same interarrival distributions and the same service time distributions with fixed smaller than one traffic intensity.