• Journal of Information Technology Applications and Management
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• v.20 no.4
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• pp.47-66
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• 2013

Recently, with the diffusion of a new paradigm named as the creative economy, the government's interests and efforts regarding support of SMEs' R&D have been concentrated. In particular, due to the dominant perception that the fundamental science and original technology from government-funded research institutes can further enhance the capabilities of SMEs' R&D, the importance of performance's diffusion on national R&D is further emphasized. In fact, the domestic SMEs don't have enough budget and workforce, so that all of self-contained technologies, product's competitiveness as well as the R&D capabilities, are very vulnerable, and thereby SMEs' commercialization is very likely to fail. For this end, SMEs need to adopt the concept of open innovation as the use of external R&D resources by licensing. In this study, we conducted a survey on a total of 286 domestic IT SMEs, and analyzed empirically to compare the degree of their acceptance on technological innovation between two groups divided by open/not-open innovation. As a result, we drew some of the key factors influencing the acceptance of the SMEs' open technological innovation, and found a variety of implications through them.

• The Journal of Korean Physical Therapy
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• v.35 no.6
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• pp.190-194
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• 2023

Purpose: Traumatic brain injury (TBI) refers to brain damage caused by external forces or trauma. TBIs can vary in severity and result from accidents, falls, sports injuries, assaults, or other forms of physical trauma. The prefrontal cortex (PFC) is known have roles in various cognitive functions. We report on a patient with traumatic brain injury who showed prefrontal symptoms after injury of thalamocortical connections between mediodorsal nuclei (MD) of thalamus and PFC. Methods: A 54-year-old, male patient suffered a TBI as a result of a heavy object falling on his head. After onset of TBI, he showed typical symptoms of prefrontal lobe injury, including personality changes, memory impairment, and general cognition problem. The thalamocortical connections between MD and PFC (ventrolateral prefrontal cortex (VLPFC), dorsolateral prefrontal cortex (DLPFC), and obrbitofrontal cortex (OFC)) were reconstructed using diffusion tensor tractography. In terms of fractional anisotropy value, the right thalamocortical connections to the OFC were significantly lower than those of control subjects. Results: The value of mean diffusivity in the right thalamocortical connections to the DLPFC was significantly higher than that of control subjects. By contrast, both VLPFC and left OFC showed significant decrement in the tract volume of thalamocortical connections compared with that of control subjects. Conclusion: We reported on a patient who showed cognitive and neuropsychiatric impairment due to global injury of the thalamocoritcal connections between MD and PFC following TBI.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.33-36
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• 2008

The transient behavior of a passive air breathing direct methanol fuel cell (DMFC) operated on vapor-feeding mode is studied in this paper. It generally takes 30 minutes after starting for the cell response to come to its steady-state and the response is sometimes unstable. A mathematical dynamic one-dimensional model for simulating transient response of the DMFC is presented. In this model a DMFC is decomposed into its subsystems using lumped model and divided into five layers, namely the anodic diffusion layer, the anodic catalyst layer, the proton exchange membrane (PEM), the cathodic catalyst layer and the cathodic diffusion layer. All layers are considered to have finite thickness, and within every one of them a set of differential-algebraic governing equations are given to represent multi-components mass balance, such as methanol, water, oxygen and carbon dioxide, charge balance, the electrochemical reaction and mass transport phenomena. A one-dimensional, isothermal and mass transport model is developed that captures the coupling between water generation and transport, oxygen consumption and natural convection. The single cell is supplied by pure methanol vapor from a methanol reservoir at the anode, and the oxygen is supplied via natural air-breathing at the cathode. The water is not supplied from external source because the cell uses the water created at the cathode using water back diffusion through nafion membrane. As a result of simulation strong effects of water transport were found out. The model analysis provides several conclusions. The performance drop after peak point is caused by insufficiency of water at the anode. The excess water at the cathode makes performance recovery impossible. The undesired crossover of the reactant methanol through the PEM causes overpotential at the cathode and limits the feeding methanol concentration.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.259-264
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• 2010

In continuous hot dip galvanizing process, oxide formation on steel surface has an influence on Zn wetting. High strength automotive steel contains high amount of Si and Mn, where Si-Mn composite oxides such as $Mn_2SiO_4$ or $MnSiO_3$ covers the surface after annealing. Zn wetting depends on how the aluminothermia reaction can reduce the Mn-Si composite oxides and then form inhibition layer such as $Fe_2Al_5$ on the steel surface. The outward diffusion of metallic ions such as $Mn^{2+}$, $Si^{2+}$ in the steel matrix is very important factor for the formation of the surface oxides on the steel surface. The surface state and grain boundaries provide an important role for the diffusion and the surface oxide reactions. Some elements such as P, Sb, and B have a strong affinity for the interface precipitation, and it influence the diffusivity of metallic ions on grain boundaries. B oxide forms very rapildly on the steel surface during the annealing, and this promote complex oxides with $SiO_2$ or MnO. P has inter-reacted with other elements on the grain boundaries and influence the diffusion through on them. Small addition of Sb could suppress the decarburization from steel surface and retards the formation of internal and external selective oxides on the steel surface. Interface control by the trace elements such as Sb could be available to improve the Zn wettability during the hot dip galvanizing.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.11
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• pp.804-811
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• 2011

The aim of this study is to evaluate the applicability of adsorption models for understanding adsorption properties of adsorbents. For this study, the adsorption charateristics of $NO_3^-$ by commercial anion exchange resin, PA-308, were investigated in bach process. The adsorption kinetic data for $NO_3^-$ by anion exchange resin showed two stage process comprising a fast initial adsorption process and a slower second adsorption process. Both the pseudo-first-order kinetic model and the pseudo-second-order kinetic model could not be used to predict the adsorption kinetics of $NO_3^-$ onto anion exchange resin for the entire sorption period. Only the fast initial portion ($t{\leq}20min$) of adsorption kinetics was found to follow pseudo-first-order kinetic model and controlled mainly by external diffusion that is very fast and high, whereas, the slower second portion (t > 20 min) of adsorption kinetics seems to be controlled by a second-order chemical reaction and by intraparticle diffusion.

• Journal of Digital Convergence
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• v.17 no.1
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• pp.43-53
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• 2019

This study has explored the trajectory of the development and diffusion of the CTLs in the Korean universities by using isomorphism theory of neo-institutionalism. Neo-institutional theorists believe that organizational structure and behavior reflects the norms and values recognized in the society rather than the organization's autonomous and rational choices. Based on the isomorphism framework, the introduction and diffusion of the CTLs in the Korean universities have been led by the government. In addition, the CTLS(Korean Association of Center for Teaching & Learning) has served as a direct basis for the normative pressures. In other words, the CTLs have been securing devices for the universities to acquire external justification by the environment, and they have been able to confirm that the system was isomorphed, in particular by meeting and agreeing with the government-set university evaluation criteria. Efforts should be made to develop unique values and strategies that enable CTLs to become engines of the development of university education in response to rapid changes in the academic environment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5A
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• pp.709-718
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• 2008

Developed is a chloride penetration analysis program in which changes of environmental conditions such as temperature, humidity and external chloride concentration, and the diffusion, convection and binding of chlorides are considered. In order to consider the changes of environmental conditions, analyses for temperature and moisture distribution are implemented simultaneously, and variation of diffusion coefficients due to temperature, humidity and age is also considered. By comparing the calculated total chloride contents with some experimental data, it has been confirmed that the proposed analysis program can trace measured chloride distribution well. Also, through some example analyses, the mechanism of accumulation of chlorides at near surface and acceleration of corrosion of steel reinforcement in case that the moisture distribution changes according to repeated drying and wetting cycles have been verified.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.1009-1014
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• 2012

The influence of magnetic fields on chemical processes has long been the subject of interest to researchers. For this time numerous investigations show that commonly the effect of a magnetic field on chemical reactions is insignificant with impact less than 10 percent. However, there are some papers that point to the observation of external magnetic field effect on chemical and biochemical systems actually having a significant impact on the reactions. Thus, of great interest is an active search for rather simple but realistic models, that are based on physically explicit assumptions and able to account for a strong effect of low magnetic fields. The present work theoretically deals with two models explaining how an applied weak magnetic field might influence the steady state of a non-equilibrium chemical system. It is assumed that external magnetic field can have effect on the rates of radical reactions occurring in a system. This, in turn, leads to bifurcation of the nonequilibrium stationary state and, thus, to a drastic change in the properties of chemical systems (temperature and reagent concentration).

• Journal of the Korean Society of Combustion
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• v.21 no.4
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• pp.23-29
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• 2016

Reactivity of gasification defined by bouardard reaction is critical parameter in efficiency of the gasifier. In this study, char reactivity of the gasification was derived from the experiments using the intrinsic reaction kinetics model. Pressurized wire mesh heating reactor (PWMR) can produce high temperature and high pressure conditions up to 50 atm and 1750 K, respectively and PWMR was designed to evaluate the intrinsic reaction kinetics of $CO_2$ gasification. In this study, Kideco and KCH (sub-bituminous Indonesian coal) were pulverized and converted into char. Experiments used the PWMR were conducted and the conditions of the temperature and pressure were 1373~1673 K, 1~40 atm. To distinguish the pressure effect from high pressurized condition, internal and external effectiveness factors were considered. Finally, the intrinsic kinetics of the Kideco and KCH coal char were derived from $n^{th}$ order reaction rate equations.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.21-21
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• 2003

To increase the light-emission efficiency of LED, we increased the internal and external quantum efficiency by suppressing the defect formation in the quantum well and by increasing the light extraction efficiency in LED, respectively. First, the internal quantum efficiency was improved by investigating the effect of a low temperature (LT) grown p-GaN layer on the In$\sub$0.25/GaN/GaN MQW in green LED. The properties of p-GaN was optimized at a low growth temperature of 900oC. A green LED using the optimized LT p-type GaN clearly showed the elimination of blue-shift which is originated by the MQW damage due to the high temperature growth process. This result was attributed to the suppression of indium inter-diffusion in MQW layer as evidenced by XRD and HR-TEM analysis. Secondly, we improved the light-extraction efficiency of LED. In spite of high internal quantum efficiency of GaN-based LED, the external quantum efficiency is still low due to the total internal reflection of the light at the semiconductor-air interface. To improve the probability of escaping the photons outside from the LED structure, we fabricated nano-sized cavities on a p-GaN surface utilizing Pt self-assembled metal clusters as an etch mask. Electroluminescence measurement showed that the relative optical output power was increased up to 80% compared to that of LED without nano-sized cavities. I-V measurement also showed that the electrical performance was improved. The enhanced LED performance was attributed to the enhancement of light escaping probability and the decrease of resistance due to the increase in contact area.