• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.389-395
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• 2018

The present work aims to report the consequences of Darcy-Forchheimer medium in flow of Cross fluid model toward a stretched surface. Flow in porous space is categorized by Darcy-Forchheimer medium. Further heat transfer characteristics are examined via thermal radiation and heat generation/absorption. Transformation procedure is used. The arising system of nonlinear ordinary differential equations is solved numerically by means of shooting method. The effects of different flow variables on velocity, temperature, concentration, skin friction, and heat transfer rate are discussed. The obtained outcomes show that velocity was enhanced with the increase in the Weissenberg number but decays with increase in the porosity parameter and Hartman number. Temperature field is boosted by thermal radiation and heat generation; however, it decays with the increase in the Prandtl number.

• IE interfaces
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• v.17 no.4
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• pp.407-413
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• 2004

Recently, many enterprises are adopting EAI (Enterprise Application Integration) technologies for integrating heterogeneous enterprise information systems. Among EAI levels, data-level integration is relatively straightforward and most popular. However, most commercial solutions provide complex functionalities and are expensive for implementing the data integration tasks at the small & medium enterprises. Also, they have their own proprietary architectures and have a restricted interoperability. Proposed in this paper is the development of a data integration middleware for facilitating data exchanges between the heterogeneous information systems. The main feature of this middleware is a explicit mapping of meta data about the relationships between source and target data. Based on this explicit mapping, users who do not have expertise in information technology at the small & medium enterprises can easily execute data exchange tasks among various information systems.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.1
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• pp.164-169
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• 1986

Walsh analysis is applied to the numerical specification of the volume distribution which is the key parameter in the formulation of the constitutive equations of heterogeneous media, indicating the geometrical state of the mixture. An example of two-dimensional volume distribution, its approximation, and the Walsh correlation coefficients are presented and the change of the information distribution in the operations is investigated. The phenomena of information concentration upon the large-scale Walsh coefficients are applied to the volumetric response of porous slids, clarifying the validity of the spherical-model calculation.

• Microbiology and Biotechnology Letters
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• v.22 no.2
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• pp.152-157
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• 1994

Inulinase of Kluyveromyces marxianus origin was produced by recombinant yeast Saccharomyces cerevisiae under the control of GAL1 promoter, to examine the expression and localization of inulinase in a repressed(galactose-free) or derepressed(galactose-containinga) medium. The inulinase gene(INU1A) was constitutively expressed at 6.7 units/ml in a repressed medium. When the cell started to utilize galactose in a derepressed medium, the INU1A gene began to be expressed, and the final expression level reached about 45 units/ml. According to be the nondenaturingPAGE analysis, inulinase produced by S. cerevisiae was found to be less glycosylated than the bakers yeast invertase. In addition, its glycosylation pattern was less heterogeneous than the K. marxianus inulinase. The supplementation of inulin or raffinose into the derepressed medium increased the cell growth rate, while the expression of INU1A was repressed. Regardless of the carbon sources examined, most of inulinase activity (more than 98%) was found in the extracellular medium, indicating excellent secretion efficiency.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2724-2730
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• 2012

A new heterogeneous acidic catalyst was successfully prepared by impregnation of silica (Aerosil 300) by an acidic ionic liquid, named 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate [$PYC_4SO_3H$][$HSO_4$], and characterized using FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques. The amount of loaded acidic ionic liquid on Aerosil 300 support was determined by acid-base titration. This new solid acidic supported heterogeneous catalyst exhibits excellent activity in the synthesis of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with aromatic aldehydes under solvent-free conditions and the desired products were obtained in very short reaction times with high yields. This catalyst has the advantages of an easy catalyst separation from the reaction medium and lower problems of corrosion. Recycling of the catalyst and avoidance of using harmful organic solvent are other advantages of this simple procedure.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.10
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• pp.4642-4660
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• 2016

One major concern of applying Multipath TCP (MPTCP) to data delivery in heterogeneous wireless networks is that the utilization of asymmetric paths with diverse networking-related parameters may cause severe packet reordering and receive buffer blocking (RB²LOC). Although many efforts are devoting to addressing MPTCP's packet reordering problems, their sender-controlled solutions do not consider balancing overhead between an MPTCP sender and receiver, and their fully MPTCP mode cannot make MPTCP achieve a desired performance. This paper proposes a novel receiver-centric buffer blocking-aware data scheduling strategy for MPTCP (dubbed MPTCP-rec) necessitating the following aims: (1) alleviating MPTCP's packet reordering and RB²LOC problems, (2) improving the MPTCP performance, and (3) balancing load between the MPTCP sender and receiver. Simulation results show that the proposed MPTCP-rec solution outperforms the existing MPTCP solutions in terms of data delivery performance in heterogeneous wireless networks.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1345-1348
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• 2012

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.41-49
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• 2005

We have developed a random heterogeneous velocity model with bimodal distribution in methane hydrate-bearing Bones. The P-wave well-log data have a von Karman type autocorrelation function and non-Gaussian distribution. The velocity histogram has two peaks separated by several hundred metres per second. A random heterogeneous medium with bimodal distribution is generated by mapping of a medium with a Gaussian probability distribution, yielded by the normal spectral-based generation method. By using an ellipsoidal autocorrelation function, the random medium also incorporates anisotropy of autocorrelation lengths. A simulated P-wave velocity log reproduces well the features of the field data. This model is applied to two simulations of elastic wane propagation. Synthetic reflection sections with source signals in two different frequency bands imply that the velocity fluctuation of the random model with bimodal distribution causes the frequency dependence of the Bottom Simulating Reflector (BSR) by affecting wave field scattering. A synthetic cross-well section suggests that the strong attenuation observed in field data might be caused by the extrinsic attenuation in scattering. We conclude that random heterogeneity with bimodal distribution is a key issue in modelling hydrate-bearing Bones, and that it can explain the frequency dependence and scattering observed in seismic sections in such areas.

• Geomechanics and Engineering
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• v.13 no.5
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• pp.775-791
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• 2017

Surface wave techniques are widely used as non-invasive method for geotechnical site characterization. Field surface wave data are collected and analyzed using different processing techniques to generate the dispersion curves, which are further used to extract the shear wave velocity profile by inverse problem solution. Characteristics of a dispersion curve depend on the subsurface layering information of a vertically heterogeneous medium. Sometimes soft layer can be found between two stiff layers in the vertically heterogeneous media, and it can affect the wave propagation dramatically. Now most of the surface wave techniques use the fundamental mode Rayleigh wave propagation during the inversion, but this may not be the actual scenario when a soft layer is present in a vertically layered medium. This paper presents a detailed and comprehensive study using finite element method to examine the effect of soft layers which sometimes get trapped between two high velocity layers. Determination of the presence of a soft layer is quite important for proper mechanical characterization of a soil deposit. Present analysis shows that the thickness and position of the trapped soft layer highly influence the dispersion of Rayleigh waves while the higher modes also contribute in the resulting wave propagation.

• Journal of Intelligence and Information Systems
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• v.22 no.4
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• pp.193-215
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• 2016

In recent years, the proliferation of diverse social networking services has led users to use many mediums simultaneously depending on their individual purpose and taste. Besides, while collecting information about particular themes, they usually employ various mediums such as social networking services, Internet news, and blogs. However, in terms of management, each document circulated through diverse mediums is placed in different categories on the basis of each source's policy and standards, hindering any attempt to conduct research on a specific category across different kinds of sources. For example, documents containing content on "Application for a foreign travel" can be classified into "Information Technology," "Travel," or "Life and Culture" according to the peculiar standard of each source. Likewise, with different viewpoints of definition and levels of specification for each source, similar categories can be named and structured differently in accordance with each source. To overcome these limitations, this study proposes a plan for conducting category mapping between different sources with various mediums while maintaining the existing category system of the medium as it is. Specifically, by re-classifying individual documents from the viewpoint of diverse sources and storing the result of such a classification as extra attributes, this study proposes a logical layer by which users can search for a specific document from multiple heterogeneous sources with different category names as if they belong to the same source. Besides, by collecting 6,000 articles of news from two Internet news portals, experiments were conducted to compare accuracy among sources, supervised learning and semi-supervised learning, and homogeneous and heterogeneous learning data. It is particularly interesting that in some categories, classifying accuracy of semi-supervised learning using heterogeneous learning data proved to be higher than that of supervised learning and semi-supervised learning, which used homogeneous learning data. This study has the following significances. First, it proposes a logical plan for establishing a system to integrate and manage all the heterogeneous mediums in different classifying systems while maintaining the existing physical classifying system as it is. This study's results particularly exhibit very different classifying accuracies in accordance with the heterogeneity of learning data; this is expected to spur further studies for enhancing the performance of the proposed methodology through the analysis of characteristics by category. In addition, with an increasing demand for search, collection, and analysis of documents from diverse mediums, the scope of the Internet search is not restricted to one medium. However, since each medium has a different categorical structure and name, it is actually very difficult to search for a specific category insofar as encompassing heterogeneous mediums. The proposed methodology is also significant for presenting a plan that enquires into all the documents regarding the standards of the relevant sites' categorical classification when the users select the desired site, while maintaining the existing site's characteristics and structure as it is. This study's proposed methodology needs to be further complemented in the following aspects. First, though only an indirect comparison and evaluation was made on the performance of this proposed methodology, future studies would need to conduct more direct tests on its accuracy. That is, after re-classifying documents of the object source on the basis of the categorical system of the existing source, the extent to which the classification was accurate needs to be verified through evaluation by actual users. In addition, the accuracy in classification needs to be increased by making the methodology more sophisticated. Furthermore, an understanding is required that the characteristics of some categories that showed a rather higher classifying accuracy of heterogeneous semi-supervised learning than that of supervised learning might assist in obtaining heterogeneous documents from diverse mediums and seeking plans that enhance the accuracy of document classification through its usage.