• Journal of the Korea Society of Computer and Information
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• v.8 no.1
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• pp.37-43
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• 2003

The growing Internet business has required the acceleration of the development of security components. There are many different kinds of security components that have been developed in accordance with the appearance of various logs. Therefore, it is important that after the logs are collected they become integrated and need to Once the data from the logs have been collected form the IDS/Firewall/Router logs. It needs to be analyzed and formatted for standardization. This paper suggests designs that the log analyzation system could use in analyzing, detecting, and preventing intrusion in the various systems. Once the data has been analyzed it would be possible to Prevent further intrusion as well as trace the intrusion back to the source.

• Journal of the Korean Society for information Management
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• v.20 no.2
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• pp.27-41
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• 2003

Query logs are online records that capture user interactions with information retrieval systems and all the search processes. Query log analysis offers ad advantage of providing reasonable and unobtrusive means of collecting search information from a large number of users. In this paper, query logs of NAVER, a major Korean Internet search service, were analyzed to investigate the information seeking behabior of NAVER users. The query logs were collected over one week from various collecions such as comprehensive search, directory search and web ducument searc. It is expected that this study could contribute to the development and implementation of more effective web search systems and services.

• Convergence Security Journal
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• v.15 no.7
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• pp.85-96
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• 2015

In IT system, logs are an indicator of the previous key events. Therefore, when a security problem occurs in the system, logs are used to find evidence and solution to the problem. So, it is important to ensure the integrity of the stored logs. Existing schemes have been proposed to detect tampering of the stored logs after the key has been exp osed. Existing schemes are designed separately in terms of log transmission and storage. We propose a new log sys tem for integrating log transmission with storage. In addition, we prove the security requirements of the proposed sc heme and computational efficiency with existing schemes.

• Convergence Security Journal
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• v.15 no.5
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• pp.37-45
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• 2015

In IT system, logs are an indicator of the previous key events. Therefore, when a security problem occurs in the system, logs are used to find evidence and solution to the problem. So, it is important to ensure the integrity of the stored logs. Existing schemes have been proposed to detect tampering of the stored logs after the key has been exp osed. Existing schemes are designed separately in terms of log transmission and storage. We propose a new log sys tem for integrating log transmission with storage. In addition, we prove the security requirements of the proposed sc heme and computational efficiency with existing schemes.

• Educational Technology International
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• v.25 no.1
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• pp.27-65
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• 2024

The purpose of this study was to identify differences in learning patterns according to content complexity in video-based learning environments and to derive variables that have an important effect on learning achievement within particular learning contexts. To achieve our aims, we observed and collected data on learners' cognitive processes through perceived affordances, using behavioral logs and eye movements as specific indicators. These two types of reaction data were collected from 67 male and female university students who watched two learning videos classified according to their task complexity through the video learning player. The results showed that when the content complexity level was low, learners tended to navigate using other learners' digital logs, but when it was high, students tended to control the learning process and directly generate their own logs. In addition, using derived prediction models according to the degree of content complexity level, we identified the important variables influencing learning achievement in the low content complexity group as those related to video playback and annotation. In comparison, in the high content complexity group, the important variables were related to active navigation of the learning video. This study tried not only to apply the novel variables in the field of educational technology, but also attempt to provide qualitative observations on the learning process based on a quantitative approach.

• Journal of Forest and Environmental Science
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• v.14 no.1
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• pp.138-144
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• 1998

To provide further information for reutilization of the bed-logs decayed by oak mushroom(Lentinus edodes), the properties of wood-based board prepared with mixed materials of normal wood and bed-logs were examined. Wood fibers in bed-logs showed different morphology from normal wood fibers, that is, shorter length and rough surface. Thickness swelling increased with increasing mixing ratio of bed-log. On the other hand, modulus of rupture(MOR) in bending strength decreased. In products, the visual surface of board prepared from higher mixing rate of bed-log chips was smooth. Consquently, it is considered that the optimum mixing rate of bed-log to normal wood is the range of 25-50% and the bed-log can be used for raw material of board instead of normal wood.

• Journal of the Korean Wood Science and Technology
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• v.39 no.2
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• pp.163-171
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• 2011

Because Japanese cedar shows lower mechanical performance, glued-laminated timber (glulam) can be a better way to utilize Japanese cedar for structural purpose. However, low yield of higher grade lamination from log makes it difficult to design structural glulam. This study was aimed to increase the yield of higher grade lamination and provide higher efficiency of manufacturing structural lamination by ultrasonic log sorting technology. Logs were sorted by an existing log grading rule regulated by Korea Forest Research Institute (KFRI). It was found that the KFRI log grading rule contributed to finding better logs in viewpoint of the volumetric yield and it can reduce the number of rejected lumber by visual grading. However, it could not identify better logs to produce higher-grade products. To find an appropriate log-sorting-method for structural products, log diameter and ultrasonic time of flight (TOF) for the log were considered as factors to affect mechanical performance of resulting products. However, it was found that influence of log diameter on mechanical performance of resulting products was very small. The TOF showed a possibility to sort logs by mechanical performance of resulting products even though a coefficient of correlation was not strong (R = 0.6). In a case study, the log selection based on the ultrasonic TOF of the log increased the yield of the outermost tension lamination (E8 or better grade, KS F 3021) from 2.6% to 12.5% and reduced LTE5 (lower than E5 grade) lamination from 43.6% to 10.3%, compared with the existing KFRI log grading rule.

• Korean journal of applied entomology
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• v.35 no.1
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• pp.45-51
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• 1996

As the pest of the Letinus edoeds, five insect species and six animal species are investigated injuring the fresh mushroom. Of these, insect and animals, Achorutes armatus, Scaphidium amurense and Philomycus confusa caused severe damage to mushroom fruitbody, and a greate deal of damage was done to mushroom lamella by mites (Rhizoglyphis sp., and Histiostoma sp.). As the pest of Lentinus edodes bed logs, two insect species from immature bed logs, eight insects and one isopod species from matured bed logs were investigated. Of those, Moechotypa diphysis was found to be the most injurious species from both immature and matured bed logs. As the pest of Pleurotus ostreatus, six insects and the two mite species were investigated from sporophore. Of those, Lycoriella sp. and Mycophilla sp. are considered to be very serious. while two insects and five mite species were investigated from the mushroom bed. Of those, one insect (Lycoriella sp.) and two mites (Histiostoma feroniarum and Throglyphus bankslogior) found to be abundant and caused serious damage.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.33-36
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• 2007

An attempt was made to investigate the status of harmful microorganisms occurring on different kinds of oak bed-logs during shiitake cultivation. As a result, totally 14 species of harmful microorganisms, including Trametes versicolor, were confirmed. Twelve kinds of harmful microorganisms were observed on Quercus acutissima, 9 kinds on Q. mongolica and 10 kinds on Q. aliena. Diatrype stigma, Hypoxylon truncatum, Hypoxylon sp. and Trichoderma sp. occupied 75.1% of the total harmful fungi occurred on Q. acutissima. H. truncatum and Trichoderma sp. occupied 71.2% of the total harmful fungi occurred on Q. mongolica. On Q. aliena, the occurrence of H. truncatum, Trichoderma sp. and Hypoxylon howeianum was 80.3%. D. stigma and Hypoxylon sp. were observed exclusively on Q. acutissima bed-logs, and the outbreak ratios were 51.6% and 13.1%, respectively. H. truncatum was observed on 46.6% of Q. aliena bed-logs and Trichoderma sp. was observed on 30.3% of Q. mongolica bed-logs.

• Geophysics and Geophysical Exploration
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• v.7 no.1
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• pp.45-50
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• 2004

This paper describes a method of detecting formation boundaries, and permeable fractures, from frequency-domain Stoneley wave logs. Field data sets were collected between the depths of 330 and 360 m in well EE-4 in the Higashi-Hachimantai geothermal field, using a monopole acoustic logging tool with a source central frequency of 15 kHz. Stoneley wave amplitude spectra were calculated by performing a fast Fourier transform on the waveforms, and the spectra were then collected into a frequency-depth distribution of Stoneley wave amplitudes. The frequency-domain Stoneley wave log shows four main characteristic peaks at frequencies 6.5, 8.8, 12, and 13.3 kHz. The magnitudes of the Stoneley wave at these four frequencies are affected by formation properties. The Stoneley wave at higher frequencies (12 and 13.3 kHz) has higher amplitudes in hard formations than in soft formations, while the wave at lower frequencies (6.5 and 8.8 kHz) has higher amplitudes in soft formations than in hard formations. The correlation of the frequency-domain Stoneley wave log with the logs of lithology, degree of welding, and P-wave velocity is excellent, with all of them showing similar discontinuities at the depths of formation boundaries. It is obvious from these facts that the frequency-domain Stoneley wave log provides useful clues for detecting formation boundaries. The frequency-domain Stoneley wave logs are also applicable to the detection of a single permeable fracture. The procedure uses the Stoneley wave spectral amplitude logs at the four frequencies, and weighting functions. The optimally weighted sum of the four Stoneley wave spectral amplitudes becomes almost constant at all depths, except at the depth of a permeable fracture. The assumptions that underlie this procedure are that the energy of the Stoneley wave is conserved in continuous media, but that attenuation of the Stoneley wave may occur at a permeable fracture. This attenuation may take place at anyone of the four characteristic Stoneley wave frequencies. We think our multispectral approach is the only reliable method for the detection of permeable fractures.