• Title/Summary/Keyword: school bonding

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SABA (secondary structure assignment program based on only alpha carbons): a novel pseudo center geometrical criterion for accurate assignment of protein secondary structures

  • Park, Sang-Youn;Yoo, Min-Jae;Shin, Jae-Min;Cho, Kwang-Hwi
    • BMB Reports
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    • v.44 no.2
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    • pp.118-122
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    • 2011
  • Most widely used secondary structure assignment methods such as DSSP identify structural elements based on N-H and C=O hydrogen bonding patterns from X-ray or NMR-determined coordinates. Secondary structure assignment algorithms using limited $C{\alpha}$ information have been under development as well, but their accuracy is only ~80% compared to DSSP. We have hereby developed SABA (Secondary Structure Assignment Program Based on only Alpha Carbons) with ~90% accuracy. SABA defines a novel geometrical parameter, termed a pseudo center, which is the midpoint of two continuous $C{\alpha}s$. SABA is capable of identifying $\alpha$-helices, $3_{10}$-helices, and $\beta$-strands with high accuracy by using cut-off criteria on distances and dihedral angles between two or more pseudo centers. In addition to assigning secondary structures to $C{\alpha}$-only structures, algorithms using limited $C{\alpha}$ information with high accuracy have the potential to enhance the speed of calculations for high capacity structure comparison.

Development of the Magnetic Abrasive Using Sludge (Sludge를 이용한 자기 연마재 개발)

  • Kim, Hee-Nam;Yun, Yeo-Kwon;Kim, Sang-Baek;Choi, Hee-Sung;Ahn, Hyo-Jong
    • Journal of the Korean Society of Safety
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    • v.19 no.2
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    • pp.6-10
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    • 2004
  • The magnetic polishing is the useful method to finish using magnetic power of magnet. This method is one of precision polishing techniques and has an aim of the clean technology using for the pure of gas and inside of the clean pipe for transportation. The magnetic abrasive polishing method is not so common for machine that it tis not spreaded widely. There are rarely researcher in this field because of non-effectiveness of magnetic abrasive. Therefore, in ths paper deals with development of the magnetic abrasive using sludge. In this development, abrasive grain WA and GC used to resin bond fabricated low temperature. And magnetic material was fabricated from the sludge which were crused into 200 mesh and average diameter ${\o}$1.2mm ball type. The XRD analysis result show that only WA and GC abrasive and sludge crystal peaks detected which explains resin bond was not any more chemical reaction. From SEM analysis it tis found that WA and GC abrasive and sludge were stron bonding with each other by bond.

Effect of Starch and Base Paper Properties an Adhesion Problem of Corrugated Board (골판지 접착 불량에 대한 전분과 원지 특성의 영향)

  • Lee, Jin-Ho;Park, Jong-Moon;Lee, Sang-Hyun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.2 s.115
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    • pp.43-51
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    • 2006
  • Starch is widely used as an adhesive material in the paper and corrugated board industry. The adhesion problem of corrugated board is categorized by two main parts called zipper board and white glue line. The object of this research is to investigate the factors affecting the adhesion problem by the gelatinization of various starch solutions and dynamic penetration properties measurements of various commercial base paper and handsheets. Flow property of starch solution is affected by sodium hydroxide addition and reaction level. Absorption property of commercial base papers and handsheets is affected by sizing and stock composition. Optimum bonding between top/bottom liners and corrugated medium is accomplished by acceptable flow viscosity of mixed starch solution and proper adsorption characteristic of base paper.

Fault Location for Incomplete-Journey Double-Circuit Transmission Lines on Same Tower Based on Identification of Fault Branch

  • Wang, Shoupeng;Zhao, Dongmei;Shang, Liqun
    • Journal of Electrical Engineering and Technology
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    • v.12 no.5
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    • pp.1754-1763
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    • 2017
  • This paper analyses the characteristics of incomplete-journey double-circuit transmission lines on the same tower formed by single-circuit lines and double-circuit lines, and then presents a fault location algorithm based on identification of fault branch. With the relationship between the three-phase system and the double-circuit line system, a phase-mode transformation matrix for double-circuit lines can be derived. Based on the derived matrix, the double-circuit lines with faults can be decoupled, and then the fault location for an incomplete-journey double-circuit line is achieved by using modal components in the mode domain. The algorithm is divided into two steps. Firstly, the fault branch is identified by comparing the relationships of voltage amplitudes at the bonding point. Then the fault location, on the basis of the identification result, is calculated by using a two-terminal method, and only the fault distance of the actual fault branch can be obtained. There is no limit on synchronization of each terminal sampling data. The results of ATP-EMTP simulation show that the proposed algorithm can be applied within the entire line and can accurately locate faults in different fault types, fault resistances, and fault distances.

Bond behavior of PP fiber-reinforced cinder concrete after fire exposure

  • Cai, Bin;Wu, Ansheng;Fu, Feng
    • Computers and Concrete
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    • v.26 no.2
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    • pp.115-125
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    • 2020
  • To reduce the damage of concrete in fire, a new type of lightweight cinder aggregate concrete was developed due to the excellent fire resistance of cinder. To further enhance its fire resistance, Polypropylene (PP) Fibers which can enhance the fire resistance of concrete were also used in this type of concrete. However, the bond behavior of this new type of concrete after fire exposure is still unknown. To investigate its bond behavior, 185 specimens were heated up to 22, 200, 400, 600 or 800℃ for 2 h duration respectively, which is followed by subsequent compressive and tensile tests at room temperature. The concrete-rebar bond strength of C30 PP fiber-reinforced cinder concrete was subsequently investigated through pull-out tests after fire exposure. The microstructures of the PP fiber-reinforced cinder concrete and the status of the PP fibre at different temperature were inspected using an advanced scanning electron microscopy, aiming to understand the mechanism of the bonding deterioration under high temperature. The effects of rebar diameter and bond length on the bond strength of PP fiber-reinforced cinder concrete were investigated based on the test results. The bond-slip relation of PP fiber-reinforced cinder concrete after exposure at different temperature was derived based on the test results.

An experimental study on depositional environments and consolidation properties of Shihwa deposits (시화지역 퇴적층의 퇴적환경과 압밀 특성에 관한 연구)

  • Won, Jeong-Yun;Chang, Pyoung-Wuck;Kim, Dong-Beom;Son, Young-Hwan
    • Proceedings of the Korean Geotechical Society Conference
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    • 2004.03b
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    • pp.203-210
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    • 2004
  • Consolidation properties were analysed by means of depositional environments. Depositional environments including geochemical properties, porewater chemistry, sediment structures, particle size distributions and carbon age dating were analysed using undisturbed samples retrieved successively from a boring hole in the study area. Laboratory oedometer tests and anisotropic consolidated triaxial tests(CKoUC) were performed to examine the overconsolidation phenomenons. Based on the carbon age dating results and profiles of geochemical properties, porewater chemistry, salinity and pH, it was founded that the upper silt/clay complex layer was deposited under marine condition while sand and clay layers were deposited under fluvial condition. Planar laminated structures of silts and clays were dominant in marine deposits. Although there was no clear evidences that geological erosion had been occurred in marine deposits, overconsolidation ratio obtained from oedometer tests were greater than unity. Stress paths of samples behaved similar to those of normally consolidated clays. Data plotted in stress state charts proposed by Burland(1990) and Chandler(2000) showed that the marine deposits were geologically normally consolidated. These apparent overconsolidations can be explained by the fabric and chemical bonding due to the difference of the rate of deposition.

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Performance evaluation of MPCM to apply for radiant floor heating system (바닥난방시스템 적용을 위한 MPCM 성능평가)

  • Jeong, Su-Gwang;Jeon, Ji-Soo;Kim, Su-Min
    • 한국태양에너지학회:학술대회논문집
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    • 2012.03a
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    • pp.475-479
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    • 2012
  • Thermal energy storage (TES) systems using Microencapsulated phase change material (MPCM) have been recognized as one of the most advanced energy technologies in enhancing the energy efficiency and sustainability of buildings. We examined a way to incorporate MPCMs with building materials through application for wood-based flooring. Wood-based flooring is commonly used for floor finish materials of residential buildings in Korea. However, wood-based flooring has not performed the characteristic of heat storage. This study is aimed at manufacturing high thermal efficiency wood flooring by increasing its heat storage using MPCM. As a result, this study confirmed that MPCM is dispersed well in adhesive through the scanning electron microscopy analysis. From the differential scanning calorimetry analysis, it can be confirmed that this composite has the characteristic of a thermal energy storage material. Also, we analyzed how this composition was formed by physical combination through the Fourier transform infrared analysis. Also, we confirmed the bonding strength of the material by using the universal testing machine.

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A Study of the Mechanical Properties of Patch-Bonded and Riveted Repairs on Cracked Al 6061-T6 alloy Structures

  • Yoon, Young-Ki;Kim, Guk-Gi;Yoon, Hi-Seak
    • International Journal of Precision Engineering and Manufacturing
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    • v.1 no.2
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    • pp.55-60
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    • 2000
  • A comparison of Riveted and bonded repairs, bearing and net tension failures, and Al 6061-T6 plates is presented. The results are then compared with previous papers about bonded repairs on different patch materials and shapes. Aluminum alloys, including Al 6061-T6, have a face-centered-cubic crystal structure. Under normal circumstances, these types of crystal structures do not exhibit cleavage fractures even at very low temperatures. In aluminum-base structures, the cracked plate structures are frequently repaired using mechanical fasteners-either rivets of bolts- even though patch-bonding techniques are applied to repair and reinforce the structure. Static test results indicate that the riveted repairs are affected by the position of the rivers. When using the same size of patch, the bonded repair technique is stronger; the rate of elongation is also increased. Form FEM analysis, it is revealed the origin of patch debonding in patch-bonded structures is the edge of the patch along to the tensile strength.

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The Wetting Properties of UBM-coated Si-wafer to the Lead-free Solders in Si-wafer/Bumps/Glass Flip-Chip Bonding System

  • Hong, Soon-Min;Park, Jae-Yong;Park, Chang-Bae;Jung, Jae-Pil;Kang, Choon-Sik
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2000.04a
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    • pp.74-79
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    • 2000
  • In an attempt to estimate the wetting properties of wettable metal layers by wetting balance method, an analysis of wetting curves of the coating layer was performed. Based on the analysis, wetting properties of UBM-coated Si-plate were estimated by the new wettability indices. The wetting curves of the one and both sides-coated UBM layers have the similar shape and show the similar tendency to the temperature. So the wetting property estimation of one side coating is possible with wetting balance method. For UBM of Si-chip, Cr/Cu/Au UBM is better than Ti/Ni/Au in the point of wetting time. At general reflow temperature, the wettability of high melting point solders(Sn-Sb, Sn-Ag) is better than that of few melting point ones(Sn-Bi, Sn-In).The contact angle of the one side coated plate to the solder can be calculated from the farce balance equation by measuring the static state force and the tilt angle.

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The Influence of Surface Modification of Gold Nanoparticles Supported on TiO2 in the Catalytic Activity of CO Oxidation

  • Park, Da-Hee;Reddy, A.S.;Eah, Sang-Kee;Park, Jeong-Young
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.213-213
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    • 2011
  • Gold catalysts supported on TiO2 have shown a unique catalytic behavior on CO oxidation, depending on surface effects. Particle size has an influence on the surface activity. To make monodisperse Au nanoparticles, organic capping ligands, such as alkylthiols, were used by a "greener" synthesis method [1,2] and Au nanoparticles were deposited on TiO2. However, organic capping ligands must be removed for high catalytic activities by the Au nanoparticles without changing the Au size [3]. We used UV ozone treatment to decompose thiol ligands. The samples have been characterized by X-ray photoelectron spectroscopy to examine the surface modification by UV ozone treatment. We show the size distribution of the gold nanoparticles by light scattering analysis and transmission electron microscopy. Au/TiO2 have been prepared using the wetness impregnation method. The catalytic performance of CO oxidation over Au supported on TiO2 under oxidizing reaction conditions (40 Torr CO and 100 Torr O2) were tested. The results show that the catalytic activity depends on particle size and the time of UV ozone exposure, which suggests the role of sulfur bonding in determining the catalytic activity of Au/TiO2 catalysts.

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