• The KIPS Transactions:PartC
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• v.13C no.7 s.110
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• pp.821-830
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• 2006

As internet worms are spread out worldwide, the detection and filtering of worms becomes one of hot issues in the internet security. As one of implementation methods to detect worms, the Linux Netfilter kernel module can be used. Its basic operation for worm detection is a string matching where coming packet(s) on the network is/are compared with predefined worm signatures(patterns). A worm can appear in a packet or in two (or more) succeeding packets where some part of worm is in the first packet and its remaining part is in its succeeding packet(s). Assuming that the maximum length of a worm pattern is less than 1024 bytes, we need to perform a string matching up to two succeeding packets of 2048 bytes. To do so, Linux Netfilter keeps the previous packet in buffer and performs matching with a combined 2048 byte string of the buffered packet and current packet. As the number of concurrent connections to be handled in the worm detection system increases, the total size of buffer (memory) increases and string matching speed becomes low In this paper, to reduce the memory buffer size and get higher speed of string matching, we propose a string matching scheme without using buffer. The proposed scheme keeps the partial matching result of the previous packet with signatures and has no buffering for previous packet. The partial matching information is used to detect a worm in the two succeeding packets. We implemented the proposed scheme by modifying the Linux Netfilter. Then we compared the modified Linux Netfilter module with the original Linux Netfilter module. Experimental results show that the proposed scheme has 25% lower memory usage and 54% higher speed compared to the original scheme.

• The Journal of Engineering Geology
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• v.13 no.4
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• pp.419-428
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• 2003

In order to evaluate groundwater movement and the infiltration of contaminants, such as petroleum products, the determination of porosity and effective porosity is very important. Porosity and effective porosity are important physical parameters that determine the transfer and movement of water and solutes in porous media. Various methods of determining these parameters have been developed, with varying degrees of accuracy and applicability. Most of the existing methods produce static results. They do not produce instantaneous and real time of porosity and effective porosity in a porous media. In this study, we used a new permittivity method called Frequency Domain Reflectometry with Vector analyzer (FDR-V) to determine the porosity and effective porosity of some sand samples in the laboratory. The advantage of the FDR-V method is that it instantaneously determines the temporal variation of dielectric constants of porous media. Then, the porosity and the effective porosity of porous media are computed using well established empirical equations. Results obtained from the FDR-V method compared favorably with results from other permittivity methods such as gravimetric, injection and replacement tests. The ratio of effective porosity to porosity was 85 - 92 %, when FDR-V was used. This value compared favourably with 90 %, which has been usually quoted in previous studies. Considering the convenience and its applicability, the EDR-V permittivity holds a great potential in porous media and contaminant transport studies.

• Applied Microscopy
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• v.36 no.1
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• pp.7-16
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• 2006

A new remote access system for a 1.3 MV high voltage electron microscope has been developed. Almost all essential functions for HVEM operation, huck as stage control, specimen tilting, TV camera selection and image recording, are successfully embedded into this prototype of the remote system. Particularly, this system permits perfect and precise operation of the goniometer and also controls the high resolution digital camera via simple Web browsers. Transmission of control signals and communication with the microscope is accomplished via the global ring network for advanced applications development (GLORIAD). This fact makes it possible to realize virtual laboratory to carry out practical national and international HVEM collaboration by using the present system

• Cartoon and Animation Studies
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• s.36
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• pp.593-617
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• 2014

This article is aimed at evaluating the comic industries cluster in the cartoonists' perspective in terms of benefits, innovation milieu and loyalty. This article surveyed the 105 cartoonists in the Bucheon comic industries cluster, which has been established since 1998. As a result of analysis, cartoonists evaluated the comic industries cluster in term of facilities, knowledge and information, and social relationship in the positive way. However, the business network with the comic companies, the other contents industries is not established. The communication and collaboration between the cartoonists and local communities is not active in the Bucheon comic industries cluster. In addition, while comic industries cluster is effective in terms of city branding, the comic industries cluster is not effective in terms of economic impacts. In general, cartoonists' loyalty to the comic industries cluster is highly evaluated. The five factors such as knowledge, policy, urban regeneration, facilities are very significant in terms of the cartoonists' loyalty. This article concludes with a discussion of the sustainable strategies of the comic industries cluster in the context of creative city through comic resources.

• Economic and Environmental Geology
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• v.41 no.4
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• pp.427-442
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• 2008

Estimation of groundwater recharge is one of the most critical issues in sustainable management of groundwater resources. This study estimated groundwater recharge in the Junggwae-Boeun area in Ulsan City, by using the water balance and hydrogeological characteristics of geology and soil. Evapotranspiration was computed by using the Thornthwaite method, and direct runoff was determined by using the SCS-CN technique. Groundwater recharge was obtained as 266 mm/a (20.6% of the average annual precipitation, 1296 mm/a), with 779 mm/a (60.1%) of evapotranspiration and 119 mm/a (9.2%) of direct runoff. Precipitation and groundwater recharge was highly correlated, comparing with the relationships between precipitation and evapotranspiration, and between precipitation and direct runoff. This fact indicates that groundwater recharge responds more sensitively to precipitation than evapotranspiration and direct runoff do.

• Archives of design research
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• v.12 no.4
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• pp.283-292
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• 1999

As network and multimedia service has increased in educational environment, it is needed to study on digital system based educational scenarios, especially in art and design departments in which visual educational materials mainly used. Therefore, this study was conducted with three objectives: first, developing components of design database and their classification system, second, developing contents of database for fundamental form education in design, and third, developing application method of database. According to these objectives, the secondary research was implemented into two directions; the analysis of classification categories of design, and the analysis of contents and process of fundamental form design education. From the secondary research, it was found that design database should have a flexible structure with flexible components as well as fixed components to include subjective and aesthetic assessment. In the end, the application methods and user interface system of design database was developed based on design educational scenarios.

• Archives of design research
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• v.17 no.3
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• pp.167-178
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• 2004

The purpose of this treatise is to show merits and method of establishing Lotte department store design division Online Documents Communication System through illustration of examples of intranet in which internet environment convenient to use for its openness is applied for establishing Design Online Documents Communication System for fundamentals of organization. In this connection merits and effect attainable from establishing Design Outline Documents Communication System of the enterprise as found were as follows: Firstly, it brought about reduction in workload of staffs through sharing various existing resources. It reduced redundant works and enables speedy handling of works. Secondly, it was possible to exchange viewpoints and share information by pertinent parties. Thirdly, by expediting information exchange and communication among persons in charge it was possible to improve work efficiency. Fourthly, it was possible to build and operate such system at relatively low cost on the basis of web browser. Without using any other significant instrument or equipment but by linking it to business network and using existing computer system operation was possible. Fifthly, by common sharing of work exclusive to design room through on-line it was possible to improve professionalism and convenience in data preservation. Through this treatise and survey and study on process for establishing intranet it was possible to find that there were sharing work, improving work efficiency, reducing workload, saving cost and expediting communication to a significant degree.

• Archives of design research
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• v.17 no.3
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• pp.81-90
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• 2004

The reason of the appearance of Internet is regarded as a milestone since we have shared information globally in a mutual way. The important thing on this point is what contents we choose for ourselves. The Internet could be meaningless unless we use it in a certain way, which ultimately means that the Internet has to deliver something valuable to us humans. Therefore, we have looked at how we can deliver and share humanity and emotion through the Internet, also how we can instill vital power into our real life, through the Internet. Fortunately, the current study must essentially be ongoing due to its nature with perhaps a multidisciplinary team brainstorming ideas. The reason for that is that not only could we find new business models for companies, but also find out new ways to appease the human mind in the modern age. In addition, as consumers needs become more specialized and diversified, companies are expected to face up to fierce competition with the help of innovative ideas. The ever-intensifying competition requires companies to cultivate new strategic tools in order to have new, powerful and sustainable comparative advantages. The goal of this research will be to explore ways of finding a new approach. Specifically, this research is about how to use the EVC(empathetic virtual character), which, this researcher believes, can deliver emotional benefits so as to make e-branding successful. According to reports, it has been proven that this new concept including the EVC can result in tremendous success. So the goal of this research is to explore the current situation and to anticipate the future concerning virtual characters.

• Archives of design research
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• v.19 no.2 s.64
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• pp.91-98
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• 2006

The product convergence and complex application environment raise the need of multi-modal interface which enables us to interact products through various human senses. The sense of vision has been used predominantly more than any other senses for the traditional and general information gathering situation, but in the future which will be developed based on the digital network technology, the practical use of the various senses will be desired for more convenient and rational usage of the information appliances. The sense of auditory which possibility of practical use is becoming higher than ever with the sense of vision, the possible usage will be developed broader and in the various ways in the future. Based on this situation, the characteristics of the written language and the colloquial language and the comparative analysis of the difference between male and female's reaction for each language were examined through this study. To achieve this purpose, the literature research about the diverse components of the language system was peformed. Then, some peculiar characters of the sense of vision and auditory were reviewed and the appropriate experimentation was planned and carried out. The result of the accomplished experimentation was examined by the objective analysis method. The main results of this study are as follows: first, the reaction time for written language is shorter than colloquial language, second, there is a partial difference between the male's and female's reaction for those two stimuli, third, there is no selection bias between the sense of sight and the sense of hearing. I think the continuous development of the broad and diverse ways of study for various senses is needed based on this study.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.297-305
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• 1998

This study used in vivo intracellular recording in rat hippocampus to evaluate the effect of lidocaine and MK-801 on the membrane properties and the synaptic responses of individual neurons to electrical stimulation of the commissural pathway. Cells in control group typically fired in a tonic discharge mode with an average firing frequency of $2.4{\pm}0.9$ Hz. Neuron in MK-801 treated group (0.2 mg/kg, i.p.) had an average input resistance of $3.28{\pm}5.7\;M{\Omega}$ and a membrane time constant of $7.4{\pm}1.8$ ms. These neurons exhibited $2.4{\pm}0.2$ ms spike durations, which were similar to the average spike duration recorded in the neurons of the control group. Slightly less than half of these neurons were firing spontaneously with an average discharge rate of $2.4{\pm}1.1$ Hz. The average peak amplitude of the AHP following the spikes in these groups was $7.4{\pm}0.6$ mV with respect to the resting membrane potential. Cells in MK-801 and lidocaine treated group (5 mg/kg, i.c.v.) had an average input resistance of $3.45{\pm}6.0\;M{\Omega}$ and an average time constant of $8.0{\pm}1.4$ ms. The cells were firing spontaneously at an average discharge rate of $0.6{\pm}0.4$ Hz. Upon depolarization of the membrane by 0.8 nA for 400 ms, all of the tested cells exhibited accommodation of spike discharge. The most common synaptic response contained an EPSP followed by early-IPSP and late-IPSP. Analysis of the voltage dependence revealed that the early-IPSP and late-IPSP were putative $Cl^--and\;K^+-dependent$, respectively. Systemic injection of the NMDA receptor blocker, MK-801, did not block synaptic responses to the stimulation of the commissural pathway. No significant modifications of EPSP, early-IPSP, or late-IPSP components were detected in the MK-801 and/or lidocaine treated group. These results suggest that MK-801 and lidocaine manifest their CNS effects through firing pattern of hippocampal pyramidal cells and neural network pattern by changing the synaptic efficacy and cellular membrane properties.