• Corrosion Science and Technology
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• v.20 no.5
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• pp.295-307
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• 2021

Effects of ε-carbide (Fe_2.4C) on corrosion and hydrogen diffusion behaviors of ultra-strong steel sheets for automotive application were investigated using a number of experimental and analytical methods. Results of this study showed that the type of iron carbide precipitated during tempering treatments conducted at below A₁ temperatures had a significant influence on corrosion kinetics. Compared to a steel sample with cementite (Fe₃C), a steel sample with ε-carbide (Fe_2.4C) showed higher corrosion resistance during a long-term exposure to a neutral aqueous solution. In addition, the diffusion kinetics of hydrogen atoms formed by electrochemical corrosion reactions in the steel matrix with ε-carbide were slower than the steel matrix with cementite because of a comparatively higher binding energy of hydrogen with ε-carbide. These results suggest that designing steels with fine ε-carbide distributed uniformly throughout the matrix can be an effective technical strategy to ensure high resistance to hydrogen embrittlement induced by aqueous corrosion.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.1
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• pp.172-185
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• 2019

In this paper, we investigate the performance of the diffusion adaptation strategies for parameter estimation in wireless adaptive networks, where the nodes exchange information over noisy and fading wireless channels. This paper shows the differences between the effect of Rayleigh and Rician fading over wireless adaptive networks and proves that the Rician fading is a more practical model in such kinds of networks. Simulation results imply that the effect of Rayleigh fading is more degrading for the estimation process than Rician fading. Also, the simulation results show the performance of adapt then combine (ATC) diffusion algorithm is better than the combine then adapt (CTA) algorithm by merely considering noise in wireless channels. While the performance of CTA prevails ATC over the wireless adaptive network in the presence of noise plus channel fading.

• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.399-413
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• 2021

The solution of the time-dependent neutron diffusion equation can be approximated using quasi-static methods that factorise the neutronic flux as the product of a time dependent function times a shape function that depends both on space and time. A generalization of this technique is the updated modal method. This strategy assumes that the neutron flux can be decomposed into a sum of amplitudes multiplied by some shape functions. These functions, known as modes, come from the solution of the eigenvalue problems associated with the static neutron diffusion equation that are being updated along the transient. In previous works, the time step used to update the modes is set to a fixed value and this implies the need of using small time-steps to obtain accurate results and, consequently, a high computational cost. In this work, we propose the use of an adaptive control time-step that reduces automatically the time-step when the algorithm detects large errors and increases this value when it is not necessary to use small steps. Several strategies to compute the modes updating time step are proposed and their performance is tested for different transients in benchmark reactors with rectangular and hexagonal geometry.

• Asia pacific journal of information systems
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• v.7 no.3
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• pp.39-59
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• 1997

This study presents the growth strategy of outsourcing service by finding out the differences of importance between user firms and system integration(SI) firms in Korean outsourcing business, The result of data analysis reveals that there are siginificant differences between user firms and SI firms in some components of information systems(IS) outsourcing services. User firms regarded integation of distributea data centers as the prominent issue of IS environment changes. Meanwhile, SI firms chose management of IS/VAN center, office automation(OA), and management of global network, as the more important issues in the application area of outsourcing. Among the merits of outsourcing, both of them considered cost reduction and IS flexibility as the most important factors, However, they chose the difficulty of management control and the lack of operation knowledge among the demerits of outsourcing, Also, they commonly selected overall IS consulting among the components of outsourcing diffusion. In the question of future outsourcing services, user firms chose the adoption of client/server architecture, while SI firms selected the application of multimedia. These results show that there are some differences of preference between user firms and SI firms. Most of user firms consider the outsourcing to maximize information utilization, while the service suppliers focus on new IT adoption and its application to organization. For the strategic use of outsourcing services, SI firms are required to establish the diffusion strategy to meet the outsourcing needs of user firms.

• Asian Journal of Business Environment
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• v.3 no.2
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• pp.17-22
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• 2013

Purpose - This dissertation is based on previous research, and analyzes processing trade, which constitutes a major section of foreign trade in Shandong Province. Research design, data, and methodology - The study uses the survey data on polarization, which is a vital index reflecting the unbalanced growth of regional economic development. The article introduces the processing trade polarization index, and the processing trade polarization fluctuation rate, to predict the geographical polarization posture and development trends in Shandong Province. Results -The development of processing trade in Shandong Province shows the level of gradient from east to west. The first-line growth pole has been formed and developed, and the initial formation of the diffusion mechanism has taken place. However, coordination problems in accompanying regional development have become increasingly prominent. Conclusions - This study focuses on the development of processing trade strategy and suggests overall coordination of development objectives, using non-balanced development goals. According to regional characteristics and development objectives of the processing trade in Shandong Province, the region around the city is divided into innovation diffusion region, enhanced growth areas, areas expected to undertake development, and areas to upgrade in four levels, given the different policy proposals.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.115-126
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• 2019

Recently, in order to solve the traffic congestion in urban areas and to improve the peripheral environment, research on the design and construction technology development of great depth underground double-deck tunnel is under way by using the underground space in the urban area. The network type double-deck tunnel is in the form of an intersection with a small cross section and a steep slope as per construction at the base of a flatland, so that the fire smoke spreads rapidly in case of fire, which is expected to cause damage of human life. Therefore, this study is analyzed the delay effect of fire smoke diffusion according to the installation and non - installation of delay system for fire smoke diffusion at the intersection. Fire fumes were delayed up to 270 seconds when the delay system for fire smoke diffusion was installed at the intersection and it is analyzed that the greater the operating area of the delay system for fire smoke diffusion, the more preventable the damage of human life of the intersection.

• Journal of the Korean Wood Science and Technology
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• v.51 no.6
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• pp.555-568
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• 2023

The diffusion strategies of wood culture were established using the analytic hierarchy process, to prepare a diffusion plan of wood culture and wood utilization in response to climate change due to global warming. 'Standardization of wood culture', 'Valuation of wood culture', and 'Habituation of wood culture' were set as three major implementation strategies and priorities were evaluated. As a result, it was analyzed in the following order: 'Development of systematic education programs for each age group for rational and efficient use of eco-friendly wood materials and development of wood education standard guidelines linked to the curriculum', 'Preparation of scientific basis data on human compatibility and eco-friendliness of wood to ensure the reliability of wood and wood products', and 'Establishment of monitoring and improvement plan through the designation as a model school'. Through this, it was determined that an educational environment, changes in public attitudes through publicity, and expanding opportunities to use wood and wood products were necessary for wood culture diffusion. The results of this study can be used as basic data to derive the diffusion strategies of wood culture and establish a roadmap and policy implementation strategy to revitalize wood culture.

• Journal of Korea Technology Innovation Society
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• v.2 no.2
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• pp.309-325
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• 1999

If we want to overcome the current IMF-guarded economic situations as early as possible and to change the present industry structure to the new knowledge-based structure, it is a great necessity to increase the capability of technology innovation as a key factor of the international competitiveness, and to establish the infrastructure of venture business for increasing utilization of technologly and patent. Even though there has been a great increase in application and enrollment of the Industrial Property Rights (i.e. IPRs) including patent recently, the number of unused IPRs are increasing progressively every year (for example, the ratio of unused patent is about 60% in 1997), and illegal use of patent and dependance on the foreign patent are increasing sharply. This paper will suggest policy on nurturing venture business for increasing utilization of the unused IPRs, including technology transaction strategy and link strategy of the high-tech industries between metro Taejon and Chungcheong Area.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.1
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• pp.13-26
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• 2016

Service and technology for the future hyper-connected society, which is every information receive through the mobile internet, will be an Internet of Things. Thus, it is mandatory to derive key standardization work item and establish strategy for the global business with the standardization of device and service platform by the application service. In this study, by analyzing the domestic and international market trends, state of technical development, and standardization of technology, we identified the open platform is the stepping stone for achieving the goal which is establishing the virtuous circulation of IoT ecosystem. Also, we defined emphasized key standardization work item for achieving the open platform are network, server, access authentication, billing system, and software platform. After that, we proposed future strategy direction of standardization. This research could be contribute to the IoT service diffusion by realizing IP communication among low power wireless terminals and implementing light-weight standard internet protocol.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2321-2328
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• 2022

The passive safety system is adopted in an AP1000 nuclear power unit to improve the operation safety of the whole unit. However, due to boron diffusion and periodic sampling, boron dilution occurs in the core makeup tank. The boron replenishment process in the core makeup tank is essential and becomes particularly important. Based on the validated models, this article numerically investigates the influence of the replenishment flow rate and the position on the boron distribution in the core makeup tank. The thermal fatigue phenomenon of the "T" connection caused by replenishment is analyzed. Finally, the replenishment strategy is proposed to benefit both boron mixing in the core makeup tank and eliminating the thermal fatigue of the "T" connection.