• Transactions of Materials Processing
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• v.19 no.8
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• pp.502-507
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• 2010

The physical and mechanical properties and formability of sheet metals depend on preferred crystallographic orientations (texture). In this research work, the texture development and formability (plastic strain ratios) of AA1050 Al alloy sheets after 3 and 10 passes of asymmetric rolling and subsequent heat treatment were investigated. The plastic strain ratios of 10 passes asymmetrically rolled and subsequent heat treated samples are 1.3 times higher than those of the initial AA1050 Al alloy sheets. The ${\Delta}r$ of 10 passes of asymmetrically rolled and subsequent heat treated samples is 1/30 times lower than those of the initial AA1050 Al alloy sheets. The plastic strain ratios of 10 passes of asymmetrically rolled and subsequent heat treated Al sheets are higher than those of 3 passes ones. These results could be attributed to the formation of $\gamma$-fiber, ND//<111>, and the other texture components by means of asymmetric rolling in Al sheets.

• Journal of Environmental Health Sciences
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• v.27 no.3
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• pp.63-70
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• 2001

To identify and evaluate the benzidine-DNA adducts in liver and bladder, we exposed the 80 ppm benzidine to 40 sprague-dawley rats by drinking water for 4 weeks(6.2 mg/kg body wt./day). Only one benzidine-DNA adduct was found at the same site of thin layer chromatogram of $^{32}$ P-postlabeling method in the liver and bladder of exposed rats. So we know the DNA adduct formed at liver and bladder were similar to each other, which was N-(deoxyguanosin-8-yl)-N'-acetylbenzidine. Relative adduct labeling(RAL) of DNA adduct was similar to each other for 1 and 2 weeks, but that in liver was significantly higher than in bladder for 3 and 4 weeks. RAL$\times$10$^{9}$ of DNA adduct were 84.45$\pm$11.31 and 152.8$\pm$5.53 in liver, and were 24.76$\pm$7.06 and 38.00$\pm$10.57 in bladder for 3 and 4 weeks, respectively. Regression equation between liver and bladder was Y=-3.801+2.507 X(r=0.6036, p<0.01). In conclusion, benzidine-DNA adduct formed in liver was significantly higher than that in bladder, with the similar compound structure in sparague-dewley rates treated benzidine in drinking water.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.507-510
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• 2007

Piston cores retrieved from the western Ulleung Basin, East Sea were analyzed to examine the potential for hydrocarbon generation and to determine the hydrocarbon indicators. 2D multi-channel reflection seismic and Chirp data were also investigated for mapping and characterizing the geophysical hydrocarbon indicators such as BSR (bottom simulating reflector), blank zone, pock-mark etc. High organic carbon contents and sedimentation rates that suggest good condition for hydrocarbon generation. High pressure and low temperature condition, and high residual hydrocarbon concentrations are favor the formation of natural gas hydrate. In the piston cores, cracks generally oriented to bedding may indicate the gas expansion. The seismic data show several BSRs that are associated with natural gas hydrates and underlying free gas. A number of vertical to sub-vertical blank zones were well identified in the seismic sections. They often show the seismic pull-up structures, probably indicating the presence of high velocity hydrates. Numerous pockmarks were also observed in the Chirp profiles. They may indicate the presence of free gas below the hydrate stability zone as well.

• Journal of the korean society of oceanography
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• v.39 no.1
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• pp.20-25
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• 2004

The Yellow Sea is known to be a very productive region in terms of fisheries. However, its trophic status seems to be highly variable, ranging from oligotrophic to eutrophic, based on new production (NP) values. The NP and regenerated production (RP) values estimated from $^{15}N$-labelled nitrate and ammonium uptake in spring (April 1996) and winter (February 1997) during this study ranged from 0.05 to 19.8 mg $N m^{-2} d^{-1}$ and from 0.1 to 22.8 mg $N m^{-2}d^{-1}$, respectively. Our measurements and earlier observations suggested that NP in the Yellow Sea varied over the four orders of magnitude (range 0.05-180.9 mg $N m^{-2} d^{-1}$) temporally and spatially, and that RP (range 0.1-507.5 mg $N m^{-2}d^{-l}$) based on ammonium predominated during most period of the year, except in winter when both productions were low. The significant nitrogen uptake by phytoplankton below the euphotic zone and episodic entrainment of phytoplankton from below the euphotic zone into the euphotic zone, and nitrite excretion and dissolved organic nitrogen release during nitrate uptake might explain the apparent dominance of RP in the Yellow Sea.

• Structural Engineering and Mechanics
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• v.63 no.4
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• pp.497-507
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• 2017

During recent earthquakes, a significant number of concrete structures suffered extensive damage. Conventional reinforced concrete structures are designed for life-time safety that may see permanent inelastic deformation after severe earthquakes. Hence, there is a need to utilize adequate materials that have the ability to tolerate large deformation and get back to their original shape. Super-elastic shape memory alloy (SMA) is a smart material with unique properties, such as the ability to regain undeformed shape by unloading or heating. In this research, four different stories (three, five, seven and nine) of reinforced concrete (RC) buildings have been studied and subjected to near-field ground motions. For each building, two different types of reinforcement detailing are considered, including (1) conventional steel reinforcement (RC frame) and (2) steel-SMA reinforcement (SMA RC frame), with SMA bars being used at plastic zones of beams and steel bars in other regions. Nonlinear time history analyses have been performed by "SeismoStruct" finite element software. The results indicate that the application of SMA materials in plastic hinge regions of the beams lead to reduction of the residual displacement and consequently post-earthquake repairs. In general, it can be said that shape memory alloy materials reduce structural damage and retrofit costs.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.5
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• pp.507-511
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• 2008

There have been enormous technological advances in science & technology domain and frequent convergences between its sub-domains. Topic analysis with science & technology corpus is a key process to grasp topic trends and relations between topics. The main objective of this research is to show various analytic approaches with topics extracted from CiteSeer corpus, which is widely used in information technology domain. This paper will also show a case study of Onto-Frame, an R&D support system developed by KISTI, to reveal the role of topics on the system.

• Korean Journal of Human Ecology
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• v.13 no.4
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• pp.507-519
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• 2004

The purpose of this study is to explore the general trends and the correlations of parent-child conflicts, copings, and psychological well-being of single mothers and their children, and to analyze the variables explaining relationships between single mothers and their children. The subjects were 196 dyads of single mothers and their children who reside in Gwangju city and Jeonnam area. The data were analyzed with frequency, t-Test, Pearsons' r, and multiple regression by SPSS. The major findings are as follows: 1. Scores of single mothers and their children had conflicts and emotion-focused copings lower than median. Another scores of single mothers and their children had significantly higher problem solving focused copings and emotion-focused copings than their children except life satisfaction; 2. Conflicts, copings, life satisfaction, and depression of a single mother were positively related to those of children; 3. Life satisfaction of single mothers depends on the reason for spouse-loss, their own education background, and problem solving-focused copings. Also, that of children depends on problem solving-focused copings, mother-child conflicts, and the mothers' education. Depression of single mothers is dependent upon mother-child conflicts, emotion-focused copings, and mothers' education. Also, that of children is upon mother-child conflicts, emotion-focused copings, mothers' education, and problem solving-focused copings.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1271-1271
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• 2001

Water pollutants in drainage mainly consist of organic compounds. Hence, total organic carbon (TOC), chemical oxygen demand (COD), and biochemical oxygen demand (BOD) were generally used as the indices of pollution. However, these values are determined by special analyzer (TOC), titration method (COD), or microbe culture (BOD). Therefore, the development of simple and easy methods for the determination of water pollution is required. The authors reported the evaluation of water pollution by near infrared (NIR) spectroscopy in a model system with food components (Takamura et al. (200) Near Infrared Spectroscopy: Proceedings of 9th International Conference, pp. 503-507). In this study, the relationship between NIR spectra and drainage was investigated in order to develop a method for evaluation of drainage by NIR. Drainage was obtained in Nara Purification Center. The ranges of TOC, COD, and BOD were 0-130, 0-100 and 0-200, respectively. NIR transmittance spectra were recorded on NIR Systems Model 6250 Research Composition Analyzer in the wavelength range of 680-1235 and 1100-2500 nm with a quartz cell (light path: 0.5, 1, 2, 4 and 10mm) at 10-40. Statistical analysis was performed using NSAS program. A partial least squares (PLS) regression analysis was used for calibration. As the result, a good correlation between the raw NIR spectra and OC was obtained in the calibration. The best light path was 10 and 0.5mm in the wavelength range of 680-1235 and 110-2500nm, respectively. In the calibration, correlation coefficients(R) were 096-0.97 in the both range. In the prediction, however, a good correlation (R=0.89-0.96) was obtained only in the range of 6801235 nm, Similar results were obtained in the cases of COD and BOD. These results suggest the possibility that NIR spectroscopy can be used to evaluate drainage.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.497-507
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• 2018

Tactical networks are evolving into an All-IP based network for network centric warfare(NCW). Owing to the flexibility of IP based network, various military data applications including real-time and multi-media services are being integrated in tactical networks. Because each application has diverse Quality-of-service(QoS) requirements, it is crucial to develop a QoS provisioning method for guaranteeing QoS requirements efficiently. Conventionally, differentiated services(DiffServ) have been used to provide a different level of QoS for traffic flows. However, DiffServ is not designed to guarantee a specific requirement of QoS such as delay, loss, and bandwidth. Therefore, it is not suitable for military applications with a tight bound of QoS requirements. In this paper, we propose a multi-layer network virtualization scheme that allocates traffic flows having different QoS requirements to multiple virtual networks, which are constructed to support different QoS policies such as virtual network functions(VNFs), routing, queueing/active queue management(AQM), and physical layer policy. The experiment results indicate that the proposed scheme achieves lower delays and losses through multiple virtual networks having differentiated QoS policies in comparison with conventional networks.

• Food Science of Animal Resources
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• v.36 no.4
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• pp.499-507
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• 2016

In this study, traditional culture method and 16S rRNA gene analysis were applied to reveal the composition and diversity of lactic acid bacteria (LAB) of fermented cow milk, huruud and urum from Baotou and Bayannur of midwestern Inner Mongolia. Also, the quantitative results of dominant LAB species in three different types of dairy products from Baotou and Bayannur were gained by quantitative polymerase chain reaction (q-PCR) technology. Two hundred and two LAB strains isolated from sixty-six samples were identified and classified into four genera, namely Enterococcus, Lactococcus, Lactobacillus, Leuconostoc, and twenty-one species and subspecies. From these isolates, Lactococcus lactis subsp. lactis (32.18%), Lactobacillus plantarum (12.38%) and Leuconosto mesenteroides (11.39%) were considered as the dominated LAB species under the condition of cultivating in MRS and M17 medium. And the q-PCR results revealed that the number of dominant species varied from samples to samples and from region to region. This study clearly shows the composition and diversity of LAB existing in fermented cow milk, huruud and urum, which could be considered as valuable resources for LAB isolation and further probiotic selection.