• Journal of the Korean Wood Science and Technology
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• v.43 no.2
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• pp.156-167
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• 2015

The aim of this study was to determine the physical and mechanical properties of glued laminated timber (glulam) manufactured from small-diameter logs of three wood species, Acacia mangium (mangium), Maesopsis eminii (manii), and Falcataria moluccana (sengon), with densities of 533, 392, and $271kg/m^3$, respectively. Glulam measuring 5 cm by 7 cm by 160 cm in thickness, width, and length, respectively, was made with three to five lamina, or layers, and isocyanate adhesive. The glulams contained either the same wood species for all layers or a combination of mangium face and back layers with a core layer of manii or sengon. Solid wood samples of the same size for all three species were included as a basis for comparison. Physical-mechanical properties and delamination tests of glulam referred to JAS 234:2003. The results showed that the properties of same species glulam did not differ from those of solid wood, with the exception of the shear strength of glulam being lower than that of solid wood. Wood species affected glulam properties, but three- and five-layer glulams were not different except for the modulus of elasticity. All glulams were resistant to delamination by immersion in both cold and boiling water. The glulams that successfully met the JAS standard were three- and five-layer mangium, five-layer manii, and five-layer mangium-manii glulams.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.112-117
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• 2005

Geophysical logging is routinely undertaken as part of most coal mine exploration programs. Currently, the main application for the logs is to determine coal seam depth and to qualitatively estimate coal quality, lithology, and rock strength. However, further information can be obtained, if quantitative log interpretation is made. To assist in the uptake of quantitative interpretation, we discuss log responses in terms of the mineralogy of the clastic sedimentary rocks frequently found in the Australian black coal mining areas of the Sydney and Bowen Basins. We find that the log responses can be tied to the mineralogy with reasonable confidence. Ambiguities in the interpretation will be better resolved if a full suite of logs is run. A method for checking for internal consistency, by comparing calculated and observed velocities, is also described. A key driver for quantitative interpretation is geotechnical characterisation. We propose a classification system for clastic rocks that takes into consideration physical rock properties that can be inferred from geophysical logs.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.4
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• pp.101-114
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• 2011

As it seems like critical information leakages have been increasing due to industrial espionage and malicious internal users, the importance of introducing audit and log security technology is growing every now and then. In this paper, we suggest the session logging system for the company's internal control to meet the SOX legislation level, by monitoring and analyzing users behaviors connecting to the business-critical Operating System. The system proposed in this paper aims to monitor the user's illegal activities in the Operating System, and to present the clear evidence of purpose of those activities by detailed logs. For this purpose, we modified Operating System by adding multiple services suggested in this paper. These services utilize interfaces provided by the existing Operating System and add functions to control access and get logs. The system saves and manages session logs of users or administrators connected to the server with centralized log storage. And the system supports session log searching and lookup features required by SOX legislation for the company's internal controls with the level of computer forensics and logging technology.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.1
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• pp.67-80
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• 2012

Recently as the number of smartphone user is growing rapidly, android is also getting more interest in digital forensic. However, there is not enough research on digital data acquisition and analysis based on android platform's unique characteristics so far. Android system stores all the related recent systemwide logs from the system components to applications in volatile memory, and therefore, the logs can potentially serve as important evidences. In this paper, we propose a digital data acquisition and analysis system for android which extracts meaningful information based on the correlation of android logs and user activities from a device at runtime. We also present an efficient search scheme to facilitate realtime analysis on site. Finally, we demonstrate how the proposed system can be used to reconstruct the sequence of user activities in a more intuitive manner, and show that the proposed search scheme can reduce overall search and analysis time approximately 10 times shorter than the normal regular search method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.8
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• pp.1205-1212
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• 2022

Cyber threat targeting ICS (Industrial Control System) has indicated drastic increases over the past decade and Cyber Incident in Critical Infrastructure such as Energy, Gas Terminal and Petrochemical industries can lead to disaster-level accidents including casualties and large-scale fires. In order to effectively respond to cyber attacks targeting ICS, a multi-layered defense-in-depth strategy considering Control System Architecture is necessary. In particular, the centralized security log system integrating OT (Operational Technology) and IT (Information Technology) plays an important role in the ICS incident response plan. The paper suggests the way of implementing centralized security log system that collects security events and logs using OPC Protocol from Level 0 to Level 5 based on IEC62443 Purdue Model to integrate ICS security logs with SIEM (Security Information Event Management) operated in IT environment.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.73-79
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• 2004

Research investigated the variation of density, weight loss and dimensional decreasing rate, heat conduction rate by the resin impregnation rate and burning temperature of woodceramics, which were formed by impregnation rate of 40~80% and burning temperature of 600~1500℃ with sawdust board impregnated with phenolic resin made from thinned logs of pinus densiflora, Larix kaemferi and pinus koraiensis. As the resin impregnation rate and the burning temperature increased, the density increased, however, as the burning temperature increased to at 1200℃ or more, the density decreased. The more the resin impregnation rate increased, the more the decreasing rate of weight and size decreased; the more the burning temperature increased, the more the decreasing rate of weight and size increased. When the resin impregnation rate was high, the heat conduction (mm/sec) was superior.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.58-65
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• 2002

This research was carried out to develop field treatment techniques of thinned small diameter softwood logs and less utilized hardwood logs using sap displacement method. In this paper, we report the feasibility of using transpiration method and butt-end method for the treatment of three softwood species and three hardwood species with preservatives, fire-retardant chemicals, and dimensional stabilizer. Butt-end method was effective as a field treatment technique compared to transpiration method when considered the treatability, easiness of treatment, productivity of treated wood, and environmental aspects related to chemical treatment, regardless of the combination of wood species and chemicals.

• Journal of Internet Computing and Services
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• v.24 no.5
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• pp.51-66
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• 2023

In this paper, we propose a new type of process discovery framework, which is named as control-path-driven process group discovery framework, to be used for process mining and process reengineering in supporting life-cycle management of business process models. In addition, we develop a process mining system based on the proposed framework and perform experimental verification through it. The process execution event logs applied to the experimental effectiveness and verification are specially defined as Process BIG-Logs, and we use it as the input datasets for the proposed discovery framework. As an eventual goal of this paper, we design and implement a control path-driven process group discovery algorithm and framework that is improved from the ρ-algorithm, and we try to verify the functional correctness of the proposed algorithm and framework by using the implemented system with a BIG-Log dataset. Note that all the process mining algorithm, framework, and system developed in this paper are based on the structural information control net process modeling methodology.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.81-95
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• 2006

In order to investigate the possibility of waste logs after oak mushroom production as a source of an alternative energy and to obtain the fundamental data of supercritical water hydrolysis that has been paid attention as a new saccharification method of lignocellulosics, supercritical water hydrolysis of normal log woods (Quercus acutissima Carruth) and waste logs was carried out. With the increase of reaction time and temperature, the color of the degradation products has been dark and the degradation rate and the crystalline index increased. However the increase of reaction pressure affected the color of the degradation products and the degradation rate at only low reaction temperature. In the early stage of the reaction, the degradation of hemicellulose was progressed, while in the late stage, the cellulose was degraded. The increase of reaction time and reaction temperature (less than $415^{\circ}C$) improved the sugar yield, while at high temperature(more than $415^{\circ}C$), the sugar yield was decreased. Based on the result of the sugar yield, the optimal hydrolysis condition of Q. acutissima Carruth by supercritical water was determined to be $415^{\circ}C$, 60 seconds and 230 pressure bar with the sugar yield of 2.68% (w/w). At the optimal condition, the supercritical water hydrolysis of waste logs after the mushroom production was carried out and the sugar yield was increased to 358% (w/w). The major degradation products of waste logs by supercritical water hydrolysis were 1,1'-oxybis-benzene and 1,2-benzendicarboxylic acid by the GC-MS analysis. At the reaction condition with low degradation rate, the fatty acids such as pentadecanoic acid, 14-methyl-heptadecanoic acid were identified. With the increase of the reaction temperature and time, the amounts of phenol and benzene were increased, but the reaction pressure did not affect the kinds of degradation products. Holocellulose content was 60.6~79.2% in the water insoluble residue and the monosaccharide yield of the water insoluble residue was 49.2~675% by the acid hydrolysis. The monosaccharide yield of water-soluble portion was increased largely by the second hydrolysis using dilute acid.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.527-533
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• 2009

This study was performed to investigate the escape of pine wood nematode (PWN), Bursaphelenchus xylophilus, from two vector species (Monochamus alternatus and M. saltuarius) through oviposition and feeding behavior. First, we checked number of PWNs escaped from M. alternatus emerged from three different cases of pine logs. In case A, healthy pine trees were cut into logs and left in pine forest infected with PWN. In case B, healthy pine trees were cut into logs, left in large screen cage, and let them oviposited by M. alternatus emerged from pine trees infested with PWN. In case C, pine trees which were harboring M. alternatus were cut into logs, and PWN was inoculated artificially. The M. alternatus adults emerged from the above three cases of pine logs were checked in the next year to know how many PWN they were harboring in their bodies. The percentages of M. alternatus harboring PWN (18.3 and 15.6%, respectively) and number of nematodes per vector ($5,713.1{\pm}9,248.3$ and $2,034.1{\pm}4,746.8$ PWNs, respectively) in case A and B logs are similar to each other. However, the percentage and the number in case C (38.3% and $20,083.1{\pm}32,188.3$ PWNs) were higher than those of case A and B. Among 52 M. alternatus adults harboring PWN from all the three cases, 20 adults (38.5%) were harboring more than 5,000 PWNs per beetle. And these 20 adults were harboring 97.9% of the total PWNs in 52 adults. Second, we checked the daily escape of PWNs from M. alternatus and M. saltuarius collected at pine forest infested with PWN. The PWN escaped from their vector body for $34.9{\pm}12.4$ days for M. alternatus, and for $23.9{\pm}16.2$ days for M. saltuarius, reaching at peak escape during the 2nd week of emergence of the two vector species. A 44.5 and 47.2% to the total PWNs escaped from vector body within 2 weeks of vector emergence for M. alternatus and M. saltuarius, respectively. The number of PWNs escaped from each vector was $3,570.6{\pm}5,189.2$ and $1,556.2{\pm}1,710.3$ for M. alternatus and M. saltuarius, respectively.