• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.338-338
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• 1994

The present study was designed to compare the effects of d-1 imonene and cineole on the benzo(a) pyrene (BP)-induced mutagenicity, BP metabol ism and lipid peroxidation. Modified Ames assay was employed to evaluate the inhibitory effect of d-1 imonene and cineole on the BP-induced mutagenici ty. The number of revertant-bearing wet Is was decreased by 44∼77% in the presence of both BP and d-1 imonene compared with that of BP alone wherease cineole decreased the nutter of revertant-bearing wet Is by 28∼45% at the concentrations between 2${\mu}$M and 2mM. d-Limonene suppressed BP metsbolism by 16, 26 and 55% at the same concentrations. The EC$\_$50/ values for d-1 imonene and cineole in inhibiting lipid peroxidation were 2.0 mM and 16mM respectively, as assayed by thiobarbituric acid method. The pre sent study showed that d-1 imonene and cineole have common ant imutagenic effects although d-1 imonene appeared to be more effective than cineole in suppressing mutation and lipid peroxidation. The results suggest that the antimutagenic effects of d-1 imonene and cineole nay be associated with alternation in enzyme activities and with inhibition of lipid pero xidation.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.10
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• pp.522-531
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• 2001

A large dispersion value in optical fiber cable should be maintained to suppress the nonlinear effect induced distortion for the narrow channel spaced DWDM system while small value of dispersion is needed for high bit rate transmission. To meet these two requirement simultaneously, dispersion distribution control method during the cabling process was exploited. And dispersion distribution cable was fabricated by the way of designing alternation sections in single cable piece with standard single mode fiber(SSMF) and newly developed negative dispersion fiber(NDF). It is shown that the discretely dispersion varying cable along the axis keep the same average dispersion value of an entire cable length as that of nonzero dispersion shifted fiber(NZDSF) with 3.6 ps/km/nm while the local dispersion is around 17 ps/km/nm of absolute value. Moreover, the developed cable had good optical and mechanical properties and the feasibility of this cable for practical use was confirmed.

• ALGAE
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• v.26 no.1
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• pp.51-60
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• 2011

Similar to other species of Gigartinaceae Chondrus crispus has an alternation of perennial, isomorphic gametophytic and sporophytic generations. As these two generations co-exist independently within populations and obtain their resources in a similar manner, intraspecific competition is expected. In populations within the southern Gulf of St. Lawrence, fronds of both generations of C. crispus occur in similar numbers. This equivalency can be related to substratum instability, where the population is dynamic with a high turn-over rate of genets. These observations support a stochastic hypothesis to account for distribution of gametophytes and sporophytes in this area. Along the Atlantic coast of Nova Scotia, where the substratum is stable, gametophytes are overwhelmingly predominant. Gametophytic predominance is greatest in the lower littoral zone where C. crispus is abundant and space is limited. Under the fucoid canopy where "free-space" exists, the gametophyte to sporophyte ratio is lower. Gametophytic and sporophytic fronds are distributed equally among different size-classes and size-distribution is not considered a competitive factor. Previous studies have shown that sporophytic fronds of C. crispus are more susceptible to infections by endophytic algae and other pathogens, and are more heavily grazed by herbivores than are gametophytic fronds. Thus, mechanistic factors are strongly implied in the selection of gametophytes in the Atlantic population.

• The Journal of Engineering Geology
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• v.8 no.2
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• pp.153-161
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• 1998

An anisotropic characteristics of stratified sedimentary rocks should be considered in the design of tunnel. The second line of Taegu subway is under construction through the sedimentary rocks which is stratified by alternation of shale and sandstone, and Tongsoe over bridge road is planned to be constructed along the subway line. Thus the subway twin tunnels will be subjected by the bridge load of 76.2 MN per pier that will be placed in between the twin tunnels of the subway line. A numerical analysis is carried out for the stability of the twin tunnel, and the result shows that the maximum principal stress of surrounding ground is increased by 5∼6 MPa and the additional displacement of concrete lining is reached up to 8∼10mm due to the external bridge load. For the safety operation of the subway, reinforcement of the tunnel structure is highly recommended.

• Journal of the Korean Society for Heat Treatment
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• v.8 no.4
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• pp.289-301
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• 1995

The effect of Air/$C_3H_8$ gas addition on the compound layer growth of steels nitrocarburised in $NH_3+Air+C_3H_8$ mixed gas atmospheres was investigated. It is considered that amount of residual $NH_3$ was varied according to alternation of Air/$C_3H_8$ mixing ratio and volume content. The compound layer formed from nitrocarburising was composed of ${\varepsilon}-Fe_{2-3}$(C, N) and ${\gamma}^{\prime}-Fe_4$(C, N). According as Air/$C_3H_8$ mixing ratio increased, the superficial content of ${\gamma}^{\prime}-Fe_4$(C, N) within the compound layer was increased, at the same time the growth rate of compound layer and porous layer was increased. In the case of alloy steel at the fixed gas composition, the growth rate of compound layer and porous layer was worse than carbon steel and compound layer phase composition structure primarily consisted of E phase. As the carbon content of materials was increasing in the given gas atmospheres, the growth rate of compound layer and porous layer was increased and the superficial content of ${\varepsilon}-Fe_{2-3}$(C, N) within the compound layer was increased.

• Journal of the Korean Geophysical Society
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• v.7 no.1
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• pp.1-10
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• 2004

Gravity, magnetic and high-resolution seismic surveys were carried out in the Powell Basin to examine tectonic structure and recent sedimentation on Dec. 2002. The trend of negative gravity anomalies along the spreading axis of the Powell Basin changes from northwest to east-west toward south. Both boundaries of the basin with the Antarctic Peninsula and the South Orkey micro-continent show negative magnetic anomalies, which indicates that the boundaries were continental rift areas in the initial stage of spreading. Magnitude of the magnetic anomalies corresponding to the axis of the basin is rather small compared to those of normal spreading axises in other regions. Such small anomalies would be caused by reduction of magnetic strength of oceanic crust below thick sediments due to thermal alternation. High-resolution (3.5 kHz) seismic profiles reveal that top of the South Scotia Ridge is a flat terrain coverd with thin coarse sediments by glacial erosion. Thick oceanic sediments are deposited in the central part of the basin. Little deformation in the oceanic sediments indicates that the Powell Basin has been in stable tectonic environment after spreading of the basin stopped.

• Journal of the Mineralogical Society of Korea
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• v.9 no.1
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• pp.43-53
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• 1996

The detailed crystal chemistry of ilmenite from the Hadong massif was studied by the EPMA, M ssbauer spectroscopy, and Rietveld structural refinement using X-ray powder diffraction data. The ilmenite-bearing anorthosite shows complicated mineral assemblage which consists of plagioclase, clinopyroxene, hornblende, biotite, chlorite, apatite, allanite, and zircon. Anorthite is andesine in composition (Ab 28-57), and clinopyroxene drops in ferro-hypersthene (Fs 62-70). Ilmenite is trigonal symmetry with R space group, whose structure shows the alternation of Fe2+ (M1 site) octahedral layer and Ti (M2 site) layer along c axis. M ssbauer spectroscopy indicates that there are three doubles which assigned to couple of Fe2+($\delta$=0.812, 0.890mm/sec) and one Fe3+($\delta$=0.303mm/sec) in octahedral sites. Their Fe3+/$\Sigma$Fe is 0.065 and chemical formula is established as Fe2+0.94Fe3+0.07Ti0.97O3 using both EPMA and M ssbauer analysis. Rietveld structural refinement reveals that site occupancies of Fe in M1 and Ti in M2 are 91.2% and 89.4%, respectively. This implies that Ti and Fe2+ are alternatively occupy M1 and M2 sites. In addition, smaller M2 site is more preferable to Fe3+ occupancy over M1.

• Convergence Security Journal
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• v.15 no.2
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• pp.33-41
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• 2015

A safe Linux system for security enhancement should have an audit ability that prohibits an illegal access and alternation of data as well as trace ability of illegal activities. In addition, construction of the log management and monitoring system is a necessity to clearly categorize the responsibility of the system manager or administrator and the users' activities. In this paper, the Linux system's Security Log is analyzed to utilize it on prohibition and detection of an illegal protrusion converting the analyzed security log into a database. The proposed analysis allows a safe management of the security log. This system will contribute to the enhancement of the system reliability by allowing quick response to the system malfunctions.

• Journal of The Korean Digital Architecture Interior Association
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• v.13 no.4
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• pp.41-50
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• 2013

One of the important point in the development of urban fishing villages is to create various alternatives providing appropriate environment of fishing villages by keeping the characteristics of each fishing village. The purpose of this study is to suggest an urban-planning alternation to main fishing villages in Busan city by adaptation of the framework analysis, by adapting differentiated strategy considering the characteristics of each fishing village and by having similarities of development direction the whole city. At the same time this study is to propose against imprudent development of certain fishing villages or staying physical issues of existing plans about fishing villages. So this study is willing to visualize the frame of village and suggest the development direction after analyzing the 6 fishing villages(Songjeong village, Millak village, Daebyeon village, Gongsu village, Duho village, Dongam village) representing Busan city by using the five development types extracted from the type of cultural city. In addition, this study is used the framework analysis as the visual tool of potential elements and development direction in fishing villages by making frame of the most revealing cultural or environmental elements.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.11a
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• pp.163-166
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• 2008

With both Gatdui and Daean areas, under construction for upgrading the old housing in Gyeongju downtown area, this study was carried out to find out implications of upgrading methods in a historical and cultural city, by using a physical survey in the areas and life survey among their residents, as well as by analysing the level of their satisfaction with and requirement for housing and their preferring housing type. The upgrading patterns of residents were analysed by examining cases constructed newly in the manner of upgrading. The findings showed that it is required for both existing authorities and private parties to assume roles and responsibilities for upgrading the old housing while recently there have been continuous conflicts between development and preservation of the historic and cultural resources within the city and even the city identity also has been neglected by residents. In addition, it is necessary to take development conditions and resident's economic situation into consideration and introduce a wide range of methods for rearrangement, by turning the importance of housing upgrading to social rearrangement for the purpose of positive alternation.