• Structural Engineering and Mechanics
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• v.23 no.3
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• pp.233-247
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• 2006

Most codes of practice state that for large in-plane structures it is necessary to account for the spatial variability of earthquake ground motion. There are essentially three effects that contribute for this variation: (i) wave passage effect, due to finite propagation velocity; (ii) incoherence effect, due to differences in superposition of waves; and (iii) the local site amplification due to spatial variation in geological conditions. This paper discusses the procedures to be undertaken in the time domain analysis of a cable-stayed bridge under spatial variability of earthquake ground motion. The artificial synthesis of correlated displacements series that simulate the earthquake load is discussed first. Next, it is described the 3D model of the International Guadiana Bridge used for running tests with seismic analysis. A comparison of the effects produced by seismic waves with different apparent propagation velocities and different geological conditions is undertaken. The results in this study show that the differences between the analysis with and without spatial variability of earthquake ground motion can be important for some displacements and internal forces, especially those influenced by symmetric modes.

• The Magazine of the IEIE
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• v.30 no.3
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• pp.295-295
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• 2003

The advantages of using analogue optical networks for delivering radio signals from a central location to many remote antenna sites have been recognized. In a telecommnications context, radio signals may be for fixed radio access, cordless or mobile networks, but the same principles apply. By making use of the high bandwidth, low loss characteristics of optical fiber, all high frequency and signal processing functions can be performed centrally and signals can then be transported over the optical network directly at the carrier frequency. The remote sites then become very simple, requiring only optoelectronic conversion, filtering and linear amplification. This shifting of the complex functionality away from the remote site allow cheap, reliable, small and light-weight radio access points with low power consumption to be deployed. In this paper, we show that an electroabsorption modulation(EAM) may be used as a single component in such a radio access point, as a passive transceiver for small-sized cell(picocells).

• The Magazine of the IEIE
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• v.30 no.3
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• pp.81-85
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• 2003

The advantages of using analogue optical networks for delivering radio signals from a central location to many remote antenna sites have been recognized. In a telecommnications context, radio signals may be for fixed radio access, cordless or mobile networks, but the same principles apply. By making use of the high bandwidth, low loss characteristics of optical fiber, all high frequency and signal processing functions can be performed centrally and signals can then be transported over the optical network directly at the carrier frequency. The remote sites then become very simple, requiring only optoelectronic conversion, filtering and linear amplification. This shifting of the complex functionality away from the remote site allow cheap, reliable, small and light-weight radio access points with low power consumption to be deployed. In this paper, we show that an electroabsorption modulation(EAM) may be used as a single component in such a radio access point, as a passive transceiver for small-sized cell(picocells).

• Korean Journal of Veterinary Service
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• v.27 no.1
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• pp.103-109
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• 2004

Babesia equi ema-1 5' intergenic(IG) nucleotide was PCR amplified and analyzed for restriction sites in order to identify a promoter region in this IG nucleotide sequence. B equi ema-1 5' IG specific primers identified a 1268 bp PCR product. The sequence had restriction sites for 34 restriction enzymes when analyzed by a computer program. Among them, 26 enzymes had only one restriction site, but the others had more than one sites. When four restriction enzymes (Bgll , HindⅢ, Kpn1 and BamH1) were treated to digest the 1268 bp nucleotide, they had restriction sites as expected by the computer program. Information of restriction sites in the 1268 bp IG nucleotide will be applied to select restriction enzymes for cloning the IG nucleotide to a vector.

• Plant Resources
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• v.7 no.2
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• pp.136-140
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• 2004

Co-segregation of male fertility with DNA markers selected by RAPD analysis as being potentially linked to the restorer gene (Rf) for Cytoplasmic male sterility (CMS) was analyzed using segregating F2 population. One RAPD marker directly linked to the Rf locus was identified. Amplification of OPT-02/570 using the STS primers generated a monomorphic band of each fertile plants randomly selected F2 progenies. From these results, this specific marker would be strongly linked to be restoring gene. The use of STS marker is effective in overcoming the reliability of the RAPD phenotype and improving their utility for MAS, co-dominant STS markers are especially very useful.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.337-344
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• 2006

This paper is concerned with the simplified criterion given in ASCE 4-98, for determining whether soil-structure interaction (SSI) analysis is required for seismic response analysis of nuclear power plant structures. In this study, the criterion is evaluated for a couple of example structures including an existing nuclear power plant and the Hualien large-scale seismic test building. Forced vibration analysis and seismic response analysis are carried out using the simple stick model with soil springs and an elaborated SSI analytical model. From the numerical analyses, it is found that the criterion may not allow the fixed-base analysis for bedrock with shear wave velocity of greater than 1,100m/s which is a well-known criterion for a rock site. In addition, it is indicated that peak amplification as well as the peak broadening specified in NRC RG 1.122. shall be considered to include the effects of SSI.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.6
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• pp.11-25
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• 2009

A method of instrumentally estimating the seismic intensity (MMI) based on Fourier Acceleration Spectrum, which is the so-called 'FAS MMI method' of Sokolov and Wald (2002), was considered for its applicability to Korea. In order to implement the FAS MMI method, the empirical models of mean (m) and standard deviation (${\sigma}$) for Korea were derived for MMI ${\leq}$ IV according to individual seismic intensity by using the site-consistent horizontal FAS of 580 records from 65 isoseismal maps prepared based on the reported MMI of Korea Meteorological Administration. The site-consistent FAS at a site were obtained by correcting the observed FAS for the difference of the site amplification function relative to that of the target site of Class D station (Yun and Suh, 2007) which was evaluated to be a representative site for the generic soil profile of Korea. The FAS m model for MMI ${\leq}$ IV follows the overall linear relation in log space according to seismic intensities, featuring the FAS mean model for MMI = IV similar to that of the global model of Sokolov and Wald (2002). The ${\sigma}$-values of the FAS model are found to be greater than those of the global model for MMI ${\geq}$ V, while significantly lower than those of the global model for MMI = IV.

• The Journal of Engineering Geology
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• v.19 no.1
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• pp.15-23
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• 2009

The site effects relating to the amplification of ground motion under earthquake loading are strongly influenced by both the subsurface soil condition and geologic structure. In this study, the site effects at the Hongseong area in Korea were examined by both the site investigation including borehole drilling and in-situ seismic tests and the site visit for acquiring geologic information of ground surface. Subsurface of Hongseong area with a major instrumental earthquake event in 1978 is composed of weathered layers of a maximum of 45 m thickness overlying bedrock. A geotechnical information system based on GIS framework was implemented to effectively find out spatial geologic structure of study area and it indicated Hongseong is a shallow and wide shaped basin. Two-dimensional finite element (FE) analyses for a representative cross-section of the Hongseong area were performed to evaluate seismic site responses. From the results of seismic responses, it was observed that the ground motions were amplified during the propagation of shear waves through the soil layer overlying the bedrock and the duration of shaking near the basin edges was prolonged due to the surface waves generated by interactions of shear waves with basin geometry. Furthermore, one-dimensional FE seismic response analyses were additionally conducted for soil sites selected in the basin, and it gives similar results to the two-dimensional seismic responses at most locations in the basin with the exception of the locations near the basin edges, because the basin in this study is very shallow and wide.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.695-701
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• 1999

The hypothalamus is the classic site of synthesis of arginine vasotocin as neurohypophyseal hormone in the chicken. However, high concentrations of arginine vasotocin were also measured in ovarian tissues by radioimmunoassay. At first, we observed specific positive signal of mRNA encoding AVT in the hypothalamus by Northern hybridization. However, we could not find any specific bands in ovarian and uterine tissues. For evidence of transcription of the arginine vasotocin gene ingonadal tissues of the chicken, this study has applied the polymerase chain reaction as a highly sensitive assay. The hypothalamus, the four largest preovulatory ovarian follicles and the shell gland (uterus) were collected at 4 h and 20 h before oviposition. The ovarian follicular tissues were separated into granulose theca interns and theca externa layers. The uterine tissues were separated into myometrium and endometrium The extracted mRNA was converted to cDNA by reverse-transcriptase using oligo-$d(T)_{15}$ primer. Then, the cDNA was amplified by Vent polymerase and arginine vasotocin specific primers. The amplification reaction was incubated by 30 cycles successively, $95^{\circ}C$, $55^{\circ}C$ and $72^{\circ}C$ earth for 1 min. Te comparisons of the mRNA levels encoding arginine vasotocin between the tissues were determined by semi-quantification methods. After amplification of the cDNA, the PCR products were detected in hypothalamus, ovarian tissues and uterine tissues. The results of semi-quantification showed that the levels of arginine vasotocin mRNA in ovarian iud uterine tissues were about from 1/50 to 1/1000 when compared to that in the hypothalamus. The very low levels of mRNA encoding arginine vasotocin in ovarian and uterine tissues probably led us to conclude that arginine vasotocin may play a role of local mediate acting autocrine and/or paracrine.

• Geotechnical Engineering
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• v.9 no.1
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• pp.7-20
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• 1993

The first Korean earthquake resistant design code was enacted in 1988. In the code, the soil factor which takes into account both the soil amplification factor and the soil -structare interaction effect is divided into three groups : soil factor, 5 : 1.0, 1.2 and 1.5. In order to assist in choosing the soil factors appropriately in the earthquake resistant design, the local site effects on the based shear force induced by earthquakes are considered in depth for typical soil conditions in Korea. The depth of the alluvial and/or weathered zone is usually not deep and the fresh rock is found at depth shallower than 20 meters, and even at about 10 meters around Seoul. One dimensional wave propagation theory and the elastic half space method are used to obtain the soil -structure interaction effect as well as the soil amplification effect. The kinematic interaction effect due to scattering of waves by pile foundation is also considered. Finally, the soil factor is recommended for each soil condition from loose state to dense, and also from shallow soil depth to deep, so that the designer can choose the factor with-out difficulty.