• Title/Summary/Keyword: CSA

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Triaxial shear behavior of calcium sulfoaluminate (CSA)-treated sand under high confining pressures

  • James Innocent Ocheme;Sakiru Olarewaju Olagunju;Ruslan Khamitov;Alfrendo Satyanaga;Jong Kim;Sung-Woo Moon
    • Geomechanics and Engineering
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    • v.33 no.1
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    • pp.41-51
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    • 2023
  • Cementitious materials such as Ordinary Portland Cement (OPC), fly ash, lime, and bitumen have been employed for soil improvement over the years. However, due to the environmental concerns associated with the use of OPC, substituting OPC with calcium sulfoaluminate (CSA) cement offers good potential for ground improvement because it is more eco-friendly. Although earlier research has investigated the stabilizing effects of CSA cement-treated sand, no attempt has been made to examine soil behavior under high confining pressure. As a result, this study aimed to investigate the shear strength and mechanical behavior of CSA cement-treated sand using a consolidated drained (CD) triaxial test with high confining pressure. The microstructure of the examined sand samples was investigated using scanning electron microscopy. This study used sand with CSA cement contents of 3%, 5%, and 7% and confining pressures of 0.5, 1.0, and 1.5 MPa. It revealed that the confining pressures and CSA cement content significantly affected the stress-strain and volumetric change behavior of CSA cement-treated sand at high confining pressures.

Thermal stability of polyaniline based conductive polymer blend (Polyaniline계 전도성 고분자의 열안정 특성)

  • 백운석;윤호규;서광석
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.11a
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    • pp.215-218
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    • 1998
  • The thermal stability of polyaniline-camphorsulfonic acid(PANI-CSA) film was studied as a function of temperature and time. A decrease in electrical conductivity of PANI-CSA film occurred when PANI-CSA film is subjected to temperature above 60$^{\circ}C$. From the result of thermogravimetry (TG), it was thought that the deterioration in electrical conductivity of PANI-CSA film was due to evaporation of water and residual solvent.

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FPGA Implementation of High Speed RSA Cryptosystem Using Radix-4 Modified Booth Algorithm and CSA (Radix-4 Modified Booth 알고리즘과 CSA를 이용한 고속 RSA 암호시스템의 FPGA 구현)

  • 박진영;서영호;김동욱
    • Proceedings of the IEEK Conference
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    • 2001.06a
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    • pp.337-340
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    • 2001
  • This paper presented a new structure of RSA cryptosystem using modified Montgomery algorithm and CSA(Carry Save Adder) tree. Montgomery algorithm was modified to a radix-4 modified Booth algorithm. By appling radix-4 modified Booth algorithm and CSA tree to modular multiplication, a clock cycle for modular multiplication has been reduced to (n+3)/2 and carry propagation has been removed from the cell structure of modular multiplier. That is, the connection efficiency of full adders is enhanced.

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A Comparative Study on the Testing Methods for the Analysis of Tensile Strength of GERP Rebars (GFRP 보강근의 인장강도 분석을 위한 시험방법 비교 연구)

  • You, Young-Chan;Park, Ji-Sun;You, Young-Jun;Park, Young-Hwan
    • Journal of the Korea Concrete Institute
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    • v.18 no.3 s.93
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    • pp.303-312
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    • 2006
  • The main objective of this experimental study is to examine the feasibilities of each testing method with various kinds of grip systems for the analysis of tensile strength of GFRP(glass fiber reinforced polymer) reinforcing bars. Three types of grip systems were examined such as resin-sleeved pipe-type grip proposed by CSA(Canadian Standard Association), frictional resistance type metal grip by ASTM(American Standard for Testing and Materials) and wedge-inserted cone-type grip normally used in prestressing tendons. Also, mechanical properties of GFRP rebars with different surface deformations were investigated for each different type of testing grip used in this study. All testing procedures including specimens preparation, set-up of test equipments and measuring devices were made according to the CSA S806-02 recommendations. From the test results, it was found that the highest tensile strengths of GFRP rebars were observed when tested by resin-sleeved grip system regardless of their different surface deformations. But tensile strengths of GFRP rebars by ASTM grip system are only 10% less than those by CSA grip system. On the other hand, CSA grip is not only difficult to prepare but also not disposable. Therefore, ASTM grip system is recommended as a practical alternative to estimate the tensile strength of GFRP rebars.

Estimation of Correlation Coefficients between Histological Parameters and Carcass Traits of Pig Longissimus Dorsi Muscle

  • Ryu, Y.C.;Rhee, M.S.;Kim, B.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.3
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    • pp.428-433
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    • 2004
  • The aim of this study was to investigate the histochemical parameters of muscle fibers, and to estimate the correlation between these histological parameters and carcass traits in pigs. A total of 230 crossbred Duroc$\times$(Yorkshire$\times$Landrace) pigs (149 gilts and 81 castrated male pigs) was evaluated. Carcass traits (carcass weight, backfat thickness, and loin eye area), muscle fiber size (crosssectional area, diameter, and perimeter), muscle fiber number (density of fibers/$mm^2$ and total number of fibers), and fiber type composition (percentages of myofibers and relative areas of each fiber type) were evaluated. Mean cross-sectional area (CSA) and type IIB fiber CSA were positively correlated to carcass weight, backfat thickness and loin eye area. Mean fiber CSA was mostly related to type IIB CSA (r=0.98) as a result of the high percentage of type IIB fibers in the longissimus muscle. Correlations between fiber diameters and perimeters were also high, and showed similar results with CSA. Mean fiber density was negatively correlated to carcass weight (r=-0.24), backfat thickness (r=-0.18) and loin eye area (r=-0.27). To the contrary, total fiber number was positively correlated with carcass weight (r=0.27) and loin eye area (r=0.53). Carcass weight and loin eyZe area were not significantly related to muscle fiber composition. For backfat thickness, there was an opposition between type IIA percentage, which was positively related and type IIB percentage, which was negatively related. Fiber type composition of type I and IIA fibers were negatively correlated to that of type IIB fibers (r=-0.67 to -0.74). In the present study, carcass weight and loin eye area were positively correlated to CSA and negatively correlated to fiber density. But, these relationships were generally low. The fiber density was strongly affected by muscle fiber size and the total fiber number was affected either by CSA of muscle fiber and loin eye area. Fiber type composition was much more related to their numerical abundance than their CSA.

Unbound Protein-Protein Docking Using Conformational Space Annealing

  • Lee, Kyoung-Rim;Joo, Kee-Hyoung;Lee, Joo-Young
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2005.09a
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    • pp.294-299
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    • 2005
  • We have studied unbound docking for 12 protein-protein complexes using conformational space annealing (CSA) combined along with statistical pair potentials. The CSA, a powerful global optimization tool, is used to search the conformational space represented by a translational vector and three Euler amgles between two proteins. The energy function consists of three statistical pair-wise energy terms; one from the distance-scaled finite ideal-gas reference state (DFIRE) approach by Zhou and the other two derived from residue-residue contacts. The residue-residue contact terms describe both attractive and repulsive interactions between two residues in contact. The performance of the CSA docking is compared with that of ZDOCK, a well-established protein-protein docking method. The results show that the application of CSA to the protein-protein docking is quite successful, indicating that the CSA combined with a good scoring function is a promising method for the study of protein-protein interaction.

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The Effects of a Parental Developmental Bibliotherapy Program for Their Young Children's Sexual Abuse Self-Protection (발달적 독서치료를 활용한 부모 대상의 유아 성학대 자기보호 교육자 훈련프로그램의 개발 및 효과검증)

  • Chun, Hui-Young
    • Journal of the Korean Home Economics Association
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    • v.47 no.9
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    • pp.37-53
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    • 2009
  • The purpose of this study was to assess the effects of a children sexual abuse (CSA) parental training program with applied developmental bibliotherapy on parents. Subjects were 54 mothers, 24 of whom participated in the program which included 8 sessions for 4 weeks. Four dependent variables were subjected to analysis of covariance (ANCOVA); mothers’ knowledge, myths and stereotypes related to CSA, and their children’s levels of prevention concepts comprehension and self-protection skills of CSA. The results showed that the program increased mothers’ knowledge of CSA and decreaesd their beliefs on myths and stereotypes, and also increased their comprehension level of CSA prevention concepts and their level of children self-protection skills. These positive effects of the program show that the program can be incorporated into early childhood education practices. We are also pursuing the development of other research programs on this subject.

The Effect of Cyclosporine A on the Expression of the Major Histocompatibility Complex Antigen Class II(MHC II) (Cyclosporine A의 MHC Class II 항원에 대한 억제 효과)

  • 박국양
    • Journal of Chest Surgery
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    • v.28 no.5
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    • pp.443-446
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    • 1995
  • The present study was designed to determine whether cyclosporine A inhibits Major Histocompatibility Complex Class II antigen[MHC II expression in the allograft rat heart myocardium. In this rat allograft study we also tried to elucidate whether CSA inhibits MHC II in a dose dependent way. Hearts were isolated from LBN rats weighing 200-250 grams and heterotopically transplantated into the abdomen of weight-matched ACI rats. The ACI rats were randomly assigned to one of the three experimental groups according to cyclosporine dosage: {1}control [no CSA , n=6 {2}CSA 5 mg/day , n=5 {3}CSA 10 mg/day, n=5. The transplanted hearts were harvested 5 days postoperatively and analyzed. MHC II expression was detected by indirect immunoperoxidase staining and quantified via computer image analysis system. The % positive area reading was obtained in each slide [50 areas per group and compared to other groups. Significant differences were noted between three groups [p<0.05 . We conclude that CSA inhibits MHC II in heterotopically transplanted allograft rat heart in a dose dependent way.

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Clinical Study on the Blood Conservative Effect of Cell Saver Apparatus During OHS (개심술시 자가수혈기의 동종혈액 요구량의 저하 효과에 관한 연구)

  • Won, Yong-Soon;Ahn, Hyuk;Rho, Joon-Ryang
    • Journal of Chest Surgery
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    • v.28 no.4
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    • pp.365-370
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    • 1995
  • We studied blood salvage effect of Cell Saver Apparatus[CSA with adult cardiac patients. This study compares blood salvage in two groups of patients undergoing valve replacement or congenital cardiac operation.Group 1 is composed with 60 patients operated during 1991-1992 using CSA. Group 2 is composed with 60 patients operated during 1990-1991. No special effort was made to salvage blood in Group 2. The average requirements in Group 1 were approximately one-fourth the amount of RBC products by Group 2. The hospital course, blood chemistry level were comparable for the two groups. CSA produced blood was concentrated, well oxygenated blood and the average amount was 830 ml. Any complication was not detected in transfusion of CSA produced blood. This study shows that CSA allows safe and practical blood salvage during adult cardiac operations.

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Effects of Binary Doping on Chiroptical, Electrochemical, and Morphological Properties of Chiral Polyaniline

  • Kim, Eunok
    • Journal of the Korean Chemical Society
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    • v.59 no.5
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    • pp.423-428
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    • 2015
  • (1S)-(+)-10-camphorsulfonic acid (CSA) and HCl were used together as a binary dopant in the electrodeposition of polyaniline (PAni). (+)-CSA and HCl were added in different mole ratios (9:1 and 6:4). (+)-CSA-doped and binary-doped PAni exhibited markedly different ultraviolet-visible and circular dichroism spectral characteristics due to differences in their conformations. Distinct helical structures are observed in the scanning electron microscopy images of (+)-CSA-doped PAni. The X-ray diffraction pattern of (+)-CSA-doped PAni exhibited remarkably higher crystallinity than that of HCl-doped PAni which is associated with the helical ordering along the polymer chains. The conformational changes due to the binary doping in chiral PAni had a significant effect on its chiroptical and electrochemical properties, morphology, and crystallinity, thus determined its conductivity.