• Bulletin of Food Technology
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• v.22 no.1
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• pp.31-40
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• 2009

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.237.1-237.1
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• 2016

Electrical properties of graphene-based field effect transistors (G-FETs) can be degraded in ambient conditions owing to physisorbed oxygen or water molecules on the graphene surface. Passivation technique is one of a fascinating strategy for fabrication of G-FETs, which allows to sustain electrical properties of graphene in the long term without disrupting its inherent properties: transparency, flexibility and thinness. Ironically, despite its importance in producing high performance graphene devices, this method has been much less studied compared to patterning or device fabrication processes. Here we report a novel surface passivation method by using atomically thin self-assembled alkane layers such as C18- NH2, C18-Br and C36 to prevent unintentional doping effects that can suppress the degradation of electrical properties. In each passivated device, we observe a shift in charge neutral point to near zero gate voltage and it maintains the device performance for 1 year. In addition, the fabricated PG-FETs on a plastic substrate with ion-gel gate dielectrics exhibit not only mechanical flexibility but also long-term stability in ambient conditions. Therefore, we believe that these highly transparent and ultra-thin passivation layers can become a promising candidate in a wide range of graphene based electronic applications.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.6
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• pp.641-649
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• 2023

This study analyzes the cool-down process of liquid hydrogen storage tanks, which have advantages in terms of large-capacity transfer, storage, and utilization as hydrogen demand increases. A hydrogen liquefaction plant is selected for analysis and an efficient tank cooling method is sought by comparing the time required for the cool-down process with the gas consumption in connection with the gassing-up process required for the operation of the liquid hydrogen storage tank. The results of this study can be referred to in the operation process after the initial start-up and maintenance of the hydrogen liquefaction plant.

• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.117-122
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• 2021

The article considers the position of scientists on the concept of "pedagogical technology", identifies the signs of pedagogical technology and existing classifications, considers non-traditional (innovative) learning technologies, as well as their practical forms of application in the educational process, summarizes the results, makes recommendations for the practical application of the studied material. The article considered the basic concepts of pedagogical technology, as well as some types of non-traditional (innovative) teaching technologies. Also, examples of the use of some elements of innovative technologies in practical educational activities are given. The choice of specific non-traditional pedagogical technologies is determined by the target orientation, content specificity, individualization of training, technical equipment of the educational institution, etc.

• Journal of Technology Innovation
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• v.15 no.1
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• pp.145-173
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• 2007

Using patent and firm-level panel data for 1982-2001, this study investigates spillover effects of patents and the strengthening of intellectual property rights on Productivity and Innovation. As well as we consider the effect of intra-industry spillovers, we extend the effect to inter-industry spillovers which implies the effects of IT industries on non-IT industries. The empirical results are summarized as follows. First, allowing for firm-level variables, market competition and technological spillovers, the strengthening of intellectual property rights does not play a significant role on innovative activities. Second, while innovative activities of domestic firms affect significantly firms' innovative activities, those of foreign firms do not. Third, innovative activities of IT industries as inter-industry spillovers play a significant role on innovative activities and labor productivities of domestic firms.

• The Journal of the Korea Contents Association
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• v.21 no.10
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• pp.409-421
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• 2021

The purpose of this study is to verify the effects of innovative technology characteristics of beauty care remote-manufacturing system on resistance and acceptance intentions to innovative technology in the era of the Fourth Industrial Revolution. A survey of 567 female consumers in their 20s and older was conducted. The collected survey data were analyzed for hypotheses verification through structural equation model analysis. First, the perceived usefulness and perceived ease to use of beauty care remote-manufacturing systems have negative effects on resistance to innovative technology. Second, resistance to beauty care remote-manufacturing systems has been shown to negatively affect acceptance intention. Third, perceived risk to beauty care remote-manufacturing systems have been shown to negatively affect acceptance intention. Through this study, it can be found that the significance of this study in that it derived factors that affect consumer' resistance and acceptance of innovative technologies and presented new trends and directions of the cosmetics manufacturing industry.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1847-1861
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• 2020

A design study was performed to improve the limit aseismic performance (LSP) of a primary heat transport system (PHTS) pump. This pump is part of the primary equipment of a prototype generation IV sodium-cooled fast reactor (PGSFR). The LSP is the maximum allowable seismic load that still ensures structural integrity. To calculate the LSP of the PHTS pump, a structural analysis model of the pump was developed and its dynamic characteristics were obtained by modal analysis. The floor response spectrum (FRS) initiated from a safety shutdown earthquake (SSE), 0.3 g, was applied to the support points of the PHTS pump, and then the seismic induced stresses were calculated. The structural integrity was evaluated according to the ASME code, and the LSP of the PHTS pump was calculated from the evaluation results. Based on the results of the modal analysis and LSP of the PHTS pump, design parameters affecting the LSP were selected. Then, ways to improve the LSP were proposed from sensitivity analysis of the selected design variables.

• Journal of the Korea Safety Management & Science
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• v.16 no.1
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• pp.53-68
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• 2014

The purpose of this study is to verify the relationships among innovative behavior, turnover intention, and job security. An additional purpose was to examine partial mediating effects on psychological ownership. The baseline of analyzing those relationships in this study is that the role of psychological ownership will be a mediator between job security and turnover intention as well as innovative behavior in the organization. To accomplish these purposes, a model was built among job security as predictor variable, the psychological ownership as mediating variable and turnover intention, and innovative behavior as criteria variables based on the studies conducted in the various areas. The 248 questionnaires surveyed from the area of DaeGu and Kyungbuk were used in the statistical analyses. The detail statistical techniques are such as descriptive analysis, reliability analysis, factor analysis, correlation analysis, and multi regression analysis. The results of the study show that job security had positively significant effect on turnover intention and innovative behavior. In addition, only the psychological ownership of organization-level thinking have partial mediating effects between job security and innovative behavior also job security and turnover intention. The results may indicate that the psychological ownership of organization-level thinking be a key factor to alleviate the turnover intention of employees and to encourage the innovative behavior during their works for the small-medium size companies showing the unstable job security.

• Journal of Convergence for Information Technology
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• v.9 no.5
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• pp.104-116
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• 2019

Transformational leadership(TL) is an effective job resource that can lead to innovative behavior. The new concern is to identify the mechanisms by which innovative behaviors persist, taking into account factors such as mediator. Therefore, this study intends to identify the mediating role of job engagement in the relationship between sub-factors of TL and innovative behavior. We conducted a questionnaire survey of 671 employees who are highly related to innovative behavior in public, private firms and utilized a structural equation analysis, mediation analysis to verify hypotheses based on previous studies. As a result, charisma and intellectual stimulation, which are sub-factors of TL were proved to influence innovative behavior through job engagement. The results of this study imply that companies need to utilize the measurement tool of job engagement and select leader with charisma and intellectual stimulation to sustain innovative behavior.

• Carbon letters
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• v.13 no.4
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• pp.205-211
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• 2012

Methanol as a carbon source in chemical vapor deposition (CVD) graphene has an advantage over methane and hydrogen in that we can avoid optimizing an etching reagent condition. Since methanol itself can easily decompose into hydrocarbon and water (an etching reagent) at high temperatures [1], the pressure and the temperature of methanol are the only parameters we have to handle. In this study, synthetic conditions for highly crystalline and large area graphene have been optimized by adjusting pressure and temperature; the effect of each parameter was analyzed systematically by Raman, scanning electron microscope, transmission electron microscope, atomic force microscope, four-point-probe measurement, and UV-Vis. Defect density of graphene, represented by D/G ratio in Raman, decreased with increasing temperature and decreasing pressure; it negatively affected electrical conductivity. From our process and various analyses, methanol CVD growth for graphene has been found to be a safe, cheap, easy, and simple method to produce high quality, large area, and continuous graphene films.