• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.941-952
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• 2012

In the present contribution the Encounter Theory (ET) (the prototype of the classical Collision Theory in rarefied gases) concepts for widely occurring diffusion assisted irreversible bulk reactions A + A ${\rightarrow}$ C and A + B ${\rightarrow}$ C in liquid solutions examined by the authors in the literature are analyzed and compared with each other for these different types of reactions. It is shown that for a particular case of equal initial concentrations $[A]_0=[B]_0$ in the reaction A + B ${\rightarrow}$ C, when the kinetics of both reactions A + A ${\rightarrow}$ C and A + B ${\rightarrow}$ C in the framework of formal chemical kinetics and ET are the same, the accumulation of macroscopic correlations breaking the concepts of independent encounters and leading to the Generalized Encounter Theory (GET) are drastically different. The influence of the force interaction and the decay of nonstable reactants on the time behavior the macroscopic correlations is also briefly discussed.

• Journal of the Korean Chemical Society
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• v.20 no.5
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• pp.340-350
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• 1976

Linear response theory is proposed to be applied for theoretical description of the phenomena in mechanical spectroscopy of solid high polymers below glass transition temperatures. The energy dissipation by sample is given in terms of certain time correlation functions. It is shown that the result leads to the result by Kirkwood on the energy loss and relaxation of cross-linked polymers, if the Liouville operator is replaced by the diffusion equation operator of Kirkwood. An approximation method of calculating the correlation functions is considered in order to show a way to calculate relaxation times. Using the approximation method, we consider a double-well potential model for energy relaxation, in order to see a connection between the present theory and a model theory used in mechanical energy relaxation phenomena of solid polymers containing pendant cyclohexyl groups at low temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.40-46
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• 1984

The extraction ratio of oil using solvent from the muscle of sardine, Sardinops melanosticta, was studied. The results were critically evaluated in the light of the theory of oil diffusion in a porous solid model. In addition the effect of temperature and moisture on the extraction rate was examined. Sardine muscle was prepared in a manner to meet the conditions required by the diffusion theory from Fick's law. The results of the model were well coincidenced to the theory derived from Fick's law. Diffusion constants at the direction to muscle fiber($D_1$) and at direction perpendicular to fiber($D_2=D_3$) when extracted at $45^{\circ}C$ were $8.16{\times}10^{-8}cm^2/sec\;and\;4.12{\times}10^{-8}cm^2/sec$, respectivly. The extraction rate was linearly propotional to absolute temperature(T) by eleventh power under the constant condition of moisture contents and muscle size. A comparison of the experiments with the highest($74.22\%$) and the lowest ($32.48\%$) moisture indicated that difference of $1\%$ in moisture contents caused to change the slope(K) of the extraction curve $0.53{\times}10^{-6}sec^{-1}$ approximately.

• Information Systems Review
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• v.19 no.4
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• pp.135-156
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• 2017

An intelligent personal assistant (IPA) is a software agent that assists people to perform basic tasks or services for an individual by commonly providing information via natural language. In spite of the versatile capabilities of the IPA to answer a user's simple information-based queries, such as the weather and driving directions, the actual usage rates for IPA services are limited to date. In this research, to evaluate the factors affecting the intention to use IPA, we develop an empirical model based on technology acceptance model, innovation diffusion theory, and IS success model. Afterward, we collect 203 questionnaires from actual users of IPAs. Finally, the structural equation model validates the causal relationship between the constructs of the model. Consequently, the innovation characteristics of IPA drawn from innovation diffusion theory, namely, relative advantage, compatibility, observability, all exerted a positive influence on perceived usefulness. Furthermore, information quality, a quality characteristic of IPA obtained from DeLone and McLean's IS success model, presented a positive effect on perceived usefulness and perceived ease of use. Finally, the perceived intelligence of IPA displayed a positive influence on perceived usefulness and ease of use. This characteristic was also a major factor that can increase the intention to use the IPA. Given these research findings, this study is significant for identifying factors that may influence the intention to use the IPA by providing strategic guidelines to relevant business operators and establishing an integrated model.

• Journal of Korea Port Economic Association
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• v.34 no.3
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• pp.159-182
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• 2018

The purpose of this study is to increase the competitiveness of big data in the maritime port organization, by understanding the expected performance and the intention to accept and use big data. In the empirical analysis of factors affecting the intention to use the big data technology for maritime port organizations, the variables employed are based on the Technology Organization Environment(TOE) and Diffusion of Innovations(DOI) theories, which are related to the acceptance of information and communication technologies. To achieve the objective of this study, an empirical analysis was conducted; this analysis targeted the personnel involved in the department of strategic planning and information technology in the related field. We set up eight hypotheses to examine the relevance between variables having three characteristics-technology, organization, and environmental characteristics. The empirical results are summarized as follows. First, it was seen that the technology characteristic, including relative advantage, complexity, and compatibility, has a significant effect on the expected performance. Second, the top management support of the organization characteristic has a significant effect, but the firm size of this characteristic has no significant effect on the expected performance. Third, the competitive pressure of the environment characteristic has a positive effect on the expected performance, while the regulatory support has no significant effect. Finally, the expected performance has a significant effect on the intention to use big data.

• Information Systems Review
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• v.19 no.1
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• pp.75-100
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• 2017

Today, firms are constantly transforming and innovating to survive under the rapidly changing business environment. The introduction of cloud computing services has become popular throughout society as a whole and is expected to result in many changes and developments not only in firms and but also in the public sector subject to innovation. The purpose of this study is to investigate the effect of the characteristics of cloud computing services on the perceived expected performance according to innovativeness based on innovation diffusion theory. The results of the analysis of the data collected from this research are as follows. The convenience and understanding of individuals' work as well as the benefits of cloud computing services to them depend on the innovative trend of cloud computing services. Further, the expectations for personal benefit and those for organizational benefit of cloud computing services are different from each other. Leading firms in the global market have been actively engaged in the utilization of cloud computing services in the public sector as well as in private firms. In consideration of the importance of cloud computing services, using cloud computing services as the target of innovation diffusion research is important. The results of the study are expected to contribute to developing future research models for the diffusion of new technologies, such as big data, digital convergence, and Internet of Things.

• Journal of the Korean Geotechnical Society
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• v.30 no.2
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• pp.77-85
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• 2014

The paper presents comparison between numerical and experimental results to verify finite element algorithm of air diffusion in three-phase porous media. The theory of two-phase flow in partially saturated soil is a fundamental study to predict the safety for $CO_2$ sequestration. Geotechnical engineering problems exposed to atmospheric pressure generally assume that air pressure is equal to zero in three-phase porous media, but the geotechnical engineering problem at a depth of about over 1 km needs to be considered in connection with deformable solid skeleton due to air pressure. Therefore, the objective of this study is to validate the numerical algorithm by comparing with results obtained from measurement of air diffusion and dissipation through drainage test.

• Journal of Computing Science and Engineering
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• v.8 no.4
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• pp.187-198
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• 2014

In this paper an efficient image encryption scheme based on cyclic rotations and multiple blockwise diffusions with two chaotic maps is proposed. A Sin map is used to generate round keys for the encryption/decryption process. A Pomeau-Manneville map is used to generate chaotic values for permutation, pixel value rotation and diffusion operations. The encryption scheme is composed of three stages: permutation, pixel value rotation and diffusion. The permutation stage performs four operations on the image: row shuffling, column shuffling, cyclic rotation of all the rows and cyclic rotation of all the columns. This stage reduces the correlation significantly among neighboring pixels. The second stage performs circular rotation of pixel values twice by scanning the image horizontally and vertically. The amount of rotation is based on $M{\times}N$ chaotic values. The last stage performs the diffusion four times by scanning the image in four different ways: block of $8{\times}8$ pixels, block of $16{\times}16$ pixels, principal diagonally, and secondary diagonally. Each of the above four diffusions performs the diffusion in two directions (forwards and backwards) with two previously diffused pixels and two chaotic values. This stage makes the scheme resistant to differential attacks. The security and performance of the proposed method is analyzed systematically by using the key space, entropy, statistical, differential and performance analysis. The experimental results confirm that the proposed method is computationally efficient with high security.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.545-550
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• 2007

The aim of this paper is to find out whether there is a difference in adopting and/or diffusing the information and communication technology (ICT) between countries. If there is, what are the primary factors that keep some countries from adopting and diffusing ICT while others do? To analyze the above problem, we adopted the Unified Theory of Acceptance and Use of Technology (UTAUT) suggested by Venkatesh et al. (2003), which consists of effort expectancy, performance expectancy and social influence. We also use the innovation diffusion functions, which are known to have the S-shape and are made up of the introduction, growth, maturity and decline phases. We do not, however, consider the decline phase, because the ICT that we are considering is not believed to be in that phase. Therefore, we researched how the three factors affect adoption in the three phases. We selected the cellular phone as the ICT, because it is considered to be the most popularly used ICT and its technology has been developing rapidly. We surveyed the cellular phone adopters in Korea, and the U.S. for 15 years from 1989 to 2003. Korea, and the U.S. represent newly developed and developed countries, respectively. For the data analysis, a survival analysis was used, as it could explain the characteristics of the potential adopters or non-adopters. We found that the ICT diffusion patterns, as well as the ICT diffusion factors, of the two countries were different. Therefore, we believe that the results of our research can be used in building strategies on reducing the digital divide gaps between countries.

• Archives of design research
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• v.16 no.2
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• pp.121-130
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• 2003

The diffusion expressive power means the flexibility of which creative power test spheres(fluency, originality) by Torrance is ability making the considerations, thoughts and concepts to the meaningful symbolic change. This study is willing to develop and improve program toward the diffusion expressive power and is to testify training effect of the students are majoring design with the object. The training programs composed of six levels which is based on the theory of Eskild Tjalve. And the parameters of each levels are element, function, number, arrangement, form geometric, size and have to practice 2 weeks at once by 12 weeks. For successful measuring the effective results of this study, 40 undergraduate junior students in the department of design are grouped to excercise with experimental pilot group and regulated group. The standard type of creative paper is used to evaluate the results of student's training. This study give proof that creative power of the experimental pilot and under training group is higher than the regulated and under comparison group at in the conclusion.