• Journal of the Korean Chemical Society
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• v.28 no.3
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• pp.149-154
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• 1984

The electrical conductivity of p-type yttrium sesquioxide has been measured as a function of temperature and of oxygen partial pressure at temperatures from 650 to 1050$^{\circ}C$C and oxygen partial pressures from $1 {\times}10^{-5}\;to\;2{\times}10^{-1}$atm. Plots of log conductivity vs. 1/T at constant oxygen partial pressures are found to be linear with low-and high-temperature dependences of conductivity. The high-temperature dependence of conductivity shows two different defect structures. The plots of log conductivity vs. log $Po_2$ are found to be linear at $Po_2$'s of $10^{-5}\;to\;10^{-1}$ atm. The electrical conductivity dependences on $Po_2$ are found to be ${{\sigma}{\propto}Po_2}^{1/6}$at $850{\sim}950^{\circ}C,\;{{\sigma}{\propto}Po_2}^{3/16}$ at $950{\sim}1050^{\circ}C\;and\;{{\sigma}{\propto}Po_2}^{1/7.5}{\sim}{{\sigma}{\propto}Po_2}^{1/8.3}\;at\;650{\sim}800^{\circ}C$, respectively. The defect structures are$O_i{''}$ at $850{\sim}950^{\circ}C$ and $V_M{'''}$ at $950{\sim}1050^{\circ}C$. The electron hole is main carrier type, however, ionic contribution is found at lower temperature portion.

• Journal of the Korea Society of Computer and Information
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• v.20 no.5
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• pp.1-12
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• 2015

NAND flash memory has being used for storage systems widely, because it has good features which are low-price, low-power and fast access speed. However, NAND flash memory has an in-place update problem, and therefore it needs FTL(flash translation layer) to run for applications based on hard disk storage. The FTL includes complex functions, such as address mapping, garbage collection, wear leveling and so on. Futhermore, implementation of the FTL on low-power embedded systems is difficult due to its memory requirements and operation overhead. Accordingly, many index data structures for NAND flash memory have being studied for the embedded systems. Overall performances of the index data structures are enhanced by a decreasing of page write counts, whereas it has increased page read counts, as a side effect. Therefore, we propose an index management method using a page mapping log table in $B^+$-Tree based on NAND flash memory to decrease page write counts and not to increase page read counts. The page mapping log table registers page address information of changed index node and then it is exploited when retrieving records. In our experiment, the proposed method reduces the page read counts about 61% at maximum and the page write counts about 31% at maximum, compared to the related studies of index data structures.

• Korean Journal of Heritage: History & Science
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• v.39
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• pp.5-38
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• 2006

Although in Korea there are only three examples of wooden coffins being found in burial mounds - from the Daho-ri, Songhyun-dong, and Munyung tombs, in Japan data on the shape and structure of wooden coffins from the Gofun era is relatively abundant. The wooden coffins of the Gofun era of Japan can be classified into either the dugout log style or the combined boards style according to their method of manufacture. They can also be divided by shape, into such categories as the boat shape, the split bamboo shape, the box shape, and so on. The box shape category can be further divided into the assembled type and the nailed type, according to how the boards are put together. Japanese Umbrella Pine (Sciadopitys verticillata) was favored as coffin-wood in all ages, but during the later Gofun era easily obtained woods such as the Japanese cedar (Cryptomeria japonica) or the Hinoki Falsecypress (Chamaecyparis obtusa) were also used. The coffins found at Daho-ri and Songhyun-dong are similar to the Japanese dugout log style in shape and manufacture, while the king's and queen's coffins excavated at Munyung Tomb are seen to have had direct influence on the appearance of nailed coffins Japan. The coffin in Songhyun-dong 7th mound was originally a dugout log boat. It was probably used for practical reasons such as the bugproof, anti-corrosion qualities of camphor wood, not because of ideological reasons such as in a boat burial (in which the boat takes the deceased to the after world). Because the Changnyong region is inland, where camphor trees do not grow, using an already existing boat may have been the only way to procure a camphor-wood coffin. From historical circumstances, it may be inferred that the camphor trees were imported into Korea from Japan, between which there was much cultural exchange.

• Economic and Environmental Geology
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• v.48 no.6
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• pp.509-523
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• 2015

This study introduces newly implemented geological well logs database for Jeju public water wells, built for a research project focusing on integrated hydrogeology database of Jeju Island. A detailed analysis of the existing 1,200 Jeju Island geological logs for the public wells developed since 1970 revealed six major indications to be improved for their use in Jeju geological logs DB construction: (1) lack of uniformity in rock name classification, (2) poor definitions of pyroclastic deposits and sand and gravel layers, (3) lack of well borehole aquifer information, (4) lack of information on well screen installation in many water wells, (5) differences by person in geological logging descriptions. A new Jeju geological logs DB enabling standardized input and output formats has been implemented to overcome the above indications by reestablishing the names of Jeju volcanic and sedimentary rocks and utilizing a commercial, database-based input structured, geological log program. The newly designed database structure in geological log program enables users to store a large number of geology, well drilling, and test data at the standardized DB input structure. Also, well borehole groundwater and aquifer test data can be easily added without modifying the existing database structure. Thus, the newly implemented geological logs DB could be a standardized DB for a large number of Jeju existing public wells and new wells to be developed in the future at Jeju Island. Also, the new geological logs DB will be a basis for ongoing project 'Developing GIS-based integrated interpretation system for Jeju Island hydrogeology'.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3973-3980
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• 2014

Prostate adenocarcinoma is one of the leading causes of cancer related mortality in men but still limited knowledge is available about its associated functional SNPs including rs1042522 (Pro72Arg). The present study was undertaken to explore the association of this SNP with susceptibility to prostate adenocarcinoma along with its structural and functional impacts in the Pakistani population in a case-control study. Three-dimensional structure of human TP53 with Pro72Arg polymorphism was predicted through homology modeling, refined and validated for detailed structure-based assessment. We also carried out a HuGE review of the previous available data for this polymorphism. Different genetic models were used to evaluate the genotypes association with the increased risk of PCa (Allelic contrast: OR=0.0.34, 95%CI 0.24-0.50, p=0.000; GG vs CC: OR=0.17, 95%CI 0.08-0.38, p=0.000; Homozygous: OR=0.08, 95%CI 0.04-0.15, p=0.000; GC vs CC: OR=2.14, 95%CI 1.01-4.51, p=0.046; Recessive model: OR=0.10, 95%CI 0.05-0.18, p=0.000; Log Additive: OR=3.54, 95%CI 2.13-5.89, p=0.000) except the Dominant model (OR=0.77, 95%CI 0.39-1.52, p=0.46). Structure and functional analysis revealed that the SNP in the proline rich domain is responsible for interaction with HRMT1L2 and WWOX. In conclusion, it was observed that the Arg coding G allele is highly associated with increased risk of prostate adenocarcinoma in the Pakistani population (p=0.000).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.644-651
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• 2021

Viral hemorrhagic septicemia virus (VHSV) is a fish pathogen responsible for causing enormous economic loss to the aquaculture industry not only in Korea but worldwide. Thus, it is necessary to identify natural compounds that can be used to control the spread of VHSV. In this study, the anti-VHSV activities of five catechol derivatives, i.e., catechol, pyrogallol, 3-methyl catechol, veratrole, and 3-methyl veratrole-extracted from green tea-were assessed. The antiviral activities of these derivatives were found to be dependent on their structure, i.e., the hydroxyl or methoxyl group and their substituent groups-on the benzene ring. Catechol, pyrogallol, and 3-methyl catechol exhibited relatively high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities than veratrole, and 3-methyl veratrole. Moreover, 3-methyl catechol harboring a methyl substituent group increased the viability of the virus-infected cells and resulted in a 2.86 log reduction in the gene copies of VHSV N (per mL) in real-time PCR analysis. In conclusion, the catechol derivatives harboring hydroxyl groups in their benzene ring exhibited higher antioxidant activities than those harboring the methoxyl groups. However, catechol derivatives with a methyl group at the 3'-position of the benzene ring exhibited higher antiviral activity than those harboring a hydroxyl group. To our knowledge, this is the first study to evaluate the relationship between the structure and the anti-VHSV activity of catechol derivatives.

• Journal of KIISE
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• v.44 no.1
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• pp.1-12
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• 2017

The continuously growing internet service requirements has resulted in a multitier system structure consisting of web server and database (DB) server. In this multitier structure, the existing intrusion detection system (IDS) detects known attacks by matching misused traffic patterns or signatures. However, malicious change to the contents at DB server through hypertext transfer protocol (HTTP) requests at the DB server cannot be detected by the IDS at the DB server's end, since the DB server processes structured query language (SQL) without knowing the associated HTTP, while the web server cannot identify the response associated with the attacker's SQL query. To detect these types of attacks, the malicious user is tracked using knowledge on interaction between HTTP request and SQL query. However, this is a practical challenge because system's source code analysis and its application logic needs to be understood completely. In this study, we proposed a scheme to find the HTTP request associated with a given SQL query using only system log files. We first generated an HTTP request-SQL query map from system log files alone. Subsequently, the HTTP request associated with a given SQL query was identified among a set of HTTP requests using this map. Computer simulations indicated that the proposed scheme finds the HTTP request associated with a given SQL query with 94% accuracy.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.4
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• pp.824-831
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• 2005

Past corporaion's network security system is single security solution, or mixed several ways, but there was inefficient system because doing not get into organic link But, constructed more strong security system by ESM enterance on. ESM uses way to integrate of each agent to manage easily various kinds security solution. That is, it is system that connect system of existent VPN, FireWall, IDS and so on configurationally depending on security policy and manage. ESM is security system that is developed more than existent security system. But, practical use of network and the development speed of technology being increasing with the mon faster speed, is heightening the level more as well as dysfunction of information crime and so on. Many improvements are required at ESM system, this research wished to make up for the weak-point in the ESM system about interior security. Studied on structure of security solution that is basis of security policy. VPN, Firewall, IDS's link that is main composition of existing security system analysis, reconstructed. And supplemented security of ESM system itself. Establish imaginary intrusion and comparative analysis access data that apply each Telnet Log analysys IDS existent ESM system and proposed ESM system comparative analysis. Confirm the importance of interior security and inspected security of proposed system.

• Applied Biological Chemistry
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• v.42 no.1
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• pp.68-72
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• 1999

The cytotoxicity of 1,3-diphenylpropenone derivatives known to inhibit the farnesyl protein transferase (FPTase) was examined against various established tumor cell line, A549 (lung cancer), SKMEL-2 (uterine cancer), HCT-15 (skin cancer), SKOV-3 (brain cancer) and XF-498 (colon cancer) of the 1,3-diphenylpropenone derivatives showing farnesyl protein transferase (FPTase) inhibition activity. And the structure-activity relationship (SAR) between structure of 1,3-diphenylpropenone derivatives as substrate and cytotoxicity was investigated by Free-Wilson analysis as well as Hansch method with tumor cell lines. From the result of Free-Wilson analyses, X-substituents on the benzoyl group have a more important role than Y-substituents on the styryl group. The 2,4-dichloro substituent, 15 and 2,4-dimethyl substituent, 16 showed the highest cytotoxicity (average pI_(50)=5.0). Particulary, the cytotoxicity of X-substituents increased with electronic effect $({\sigma})$ due to weak electron withdrawing group with optimum value $({\sigma}_{opt}=0.22{\sim}0.29})$ whereas that of Y-substituent resulted from various factors such as logP, $B_1$ and R constant.

• Korean Journal of Agricultural Science
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• v.28 no.1
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• pp.33-40
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• 2001

The authors attempted to derive a comprehensive quantitative structure-toxicity relationships (QSTRs) between various physicochemical parameters of phenyl substituents in fungicidal phenylthionocarbamate derivatives and toxicity evaluated using TOPKAT calculation. On the basis of this approach we made preditions for toxicity values for not yet tested substances with respect to these systems. The results suggested that the optimal values, $(B_2)_{opt.}=1.54_{\AA}$(Ames mutagenicity), $(R)_{opt.}=0.16$ (car-cinogenicity of male rat), $(\pi)_{opt.)=0.16$ (carcinogenicity of male mouse), $({\varepsilon}LOMO)_{opt}=-0.52e.v.$ ($LD_{50}$ of rat oral), $(B_3){opt.}=1.54_{\AA}$(chronic LOAEU), $(logP)_{opt.}=4.25$ ($LC_{50}$ of Fathead minnow) and $({\sigma})_{opt}=-0.68$ ($EC_{50}$ of Daphnia magna) of phenyl substituents were strongly correlated with the acute and chronic toxicities.