• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.4
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• pp.39-49
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• 2001

In this paper, inelastic analysis procedures are presented for the seismic performance evaluation of RC bridge piers with premature termination of main reinforcement. The mechanical characteristic of cracked concrete and reinforcing bar in concrete has been modeled, considering the bond effect between reinforcing bars and concrete, the effect of aggregate interlocking at crack surface and the stiffness degradation after the crack. The smeared crack approach is incorporated. In boundary plane at which each member with different thickness is connected, local discontinuous deformation due to the abrupt change in their stiffness can be taken into account by introducing interface element. The increase of concrete strength due to the lateral confining reinforcement has been also taken into account to model the confined concrete. The proposed numerical method for seismic performance evaluation of RC bridge piers with premature termination of main reinforcement will be verified by comparison with reliable experimental results.

• Computers and Concrete
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• v.15 no.6
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• pp.951-972
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• 2015

The focus of the present study is to investigate both local and global behaviour of a precast concrete sandwich panel. The selected prototype consists of two reinforced concrete layers coupled by a system of cold-drawn steel profiles and one intermediate layer of insulating material. High-definition nonlinear finite element (FE) models, based on 3D brick and 2D interface elements, are used to assess the capacity of this technology under shear, tension and compression. Geometrical nonlinearities are accounted via large displacement-large strain formulation, whilst material nonlinearities are included, in the series of simulations, by means of Von Mises yielding criterion for steel elements and a classical total strain crack model for concrete; a bond-slip constitutive law is additionally adopted to reproduce steel profile-concrete layer interaction. First, constitutive models are calibrated on the basis of preliminary pull and pull-out tests for steel and concrete, respectively. Geometrically and materially nonlinear FE simulations are performed, in compliance with experimental tests, to validate the proposed modeling approach and characterize shear, compressive and tensile response of this system, in terms of global capacity curves and local stress/strain distributions. Based on these experimental and numerical data, the structural performance is then quantified under various loading conditions, aimed to reproduce the behaviour of this solution during production, transport, construction and service conditions.

• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.817-823
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• 2003

We have performed ab initio calculation on the active site of HIV-1 protease. The FEP method was used to determine the binding free energy of four different of protonated states of HIV-1 protease with inhibitor. The structure of the active site and hole structure was taken from the X-ray crystallographic coordinates of the C₂ symmetric inhibitor A74704 protease bound. The active site was modeled with the fragment molecules of binding pocket, acetic acid/ acetate anion (Asp25, Asp125), formamide (amide bond of Thr26/Gly27, Thr126/ Gly127), and methanol as inhibitor fragment. All possibly protonated states of the active site were considered, which were diprotonated state (0, 0), monoprotonated (-1, 0),(0, -1) and diunprotonated state (-1, -1). Once the binding energy Debind, of each model was calculated, more probabilistic protonated states can be proposed from binding energy. From ab-initio results, the FEP simulations were performed for the three following mutations: Ⅰ) Asp25 … Asp125 → AspH25 … Asp125, ⅱ) Asp25 … Asp125 → Asp25 … AspH125, ⅲ) AspH25 … Asp125 → AspH25 … AspH125. The free energy difference between the four states gives the information of the more realistic protonated state of active site aspartic acid. These results provide a theoretical prediction of the protonation state of the catalytic aspartic residues for A74707 complex, and may be useful for the evaluation of potential therapeutic targets.

• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.51-56
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• 2010

This study was conducted to clarify the characteristics of Holstein dairy cow's vocalization in postpartum related with calf isolation. Vocalizations of 16 individuals of cows were recorded 6 hours per day (1:00am~4:00am and 1:00pm~4:00pm) using digital recorder and microphone during October 2008 and May 2009. Vocalizations were divided into 4 types. Characteristics of frequency, intensity and duration were analyzed by GLM (general linear model) and Duncan's multi-test. There were significant differences in frequency and intensity based on analyses of spectrogram and spectrum among 4 types of vocalizations. Frequencies of vocalizations were dramatically decreased on 2nd and 3rd day. Vocalization would be important factor affecting the motheryoung bond in Holstein dairy cattle.

• Molecules and Cells
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• v.27 no.6
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• pp.651-656
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• 2009

The formation of ${\beta}$-amyloid peptide ($A{\beta}$) is initiated from cleavage of amyloid precursor protein (APP) by a family of protease, ${\alpha}$-, ${\beta}$-, and ${\gamma}$-secretase. Sub W, a substrate peptide, consists of 10 amino acids, which are adjacent to the ${\beta}$-cleavage site of wild-type APP, and Sub M is Swedish mutant with double mutations on the left side of the ${\beta}$-cleavage site of APP. Sub W is a normal product of the metabolism of APP in the secretary pathway. Sub M is known to increase the efficiency of ${\beta}$-secretase activity, resulting in a more specific binding model compared to Sub W. Three-dimensional structures of Sub W and Sub M were studied by CD and NMR spectroscopy in water solution. On the basis of these structures, interaction models of ${\beta}$-secretase and substrate peptides were determined by molecular dynamics simulation. Four hydrogen bonds and one water-mediated interaction were formed in the docking models. In particular, the hydrogen bonding network of Sub M-BACE formed spread over the broad region of the active site of ${\beta}$-secretase (P5-P3'), and the side chain of P2- Asn formed a hydrogen bond specifically with the side chain of Arg235. These are more favorable to the cleavage of Sub M by ${\beta}$-secretase than Sub W. The two substrate peptides showed different tendency to bind to ${\beta}$-secretase and this information may useful for drug development to treat and prevent Alzheimer's disease.

• Korean Journal of Materials Research
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• v.28 no.6
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• pp.365-369
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• 2018

We perform density functional theory calculations to study the CO and $O_2$ adsorption chemistry of Pt@X core@shell bimetallic nanoparticles (X = Pd, Rh, Ru, Au, or Ag). To prevent CO-poisoning of Pt nanoparticles, we introduce a Pt@X core-shell nanoparticle model that is composed of exposed surface sites of Pt and facets of X alloying element. We find that Pt@Pd, Pt@Rh, Pt@Ru, and Pt@Ag nanoparticles spatially bind CO and $O_2$, separately, on Pt and X, respectively. Particularly, Pt@Ag nanoparticles show the most well-balanced CO and $O_2$ binding energy values, which are required for facile CO oxidation. On the other hand, the $O_2$ binding energies of Pt@Pd, Pt@Ru, and Pt@Rh nanoparticles are too strong to catalyze further CO oxidation because of the strong oxygen affinity of Pd, Ru, and Rh. The Au shell of Pt@Au nanoparticles preferentially bond CO rather than $O_2$. From a catalysis design perspective, we believe that Pt@Ag is a better-performing Pt-based CO-tolerant CO oxidation catalyst.

• Korean Journal of Crystallography
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• v.4 no.1
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• pp.6-10
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• 1993

11 β ,17 β -dihydroxy-9a-fluoro-l7a-methyl androst-4-en-3-one (Fluoxymesterone), CgoH29 FO,, orthorhombic, P2,2,2,, a=13.468(5) A, b= 19.554 (2)A, c=6.578(9)A, a=b=r=90˚, A (CuKa)=1.5406 A , Dm=1.289cm-3, Dc=1.299cm-3 and Z=4 at T=298k. The structure was solved by direct method using seminvariants of ggg Parity group and refined by the full-matrix least-square method, resulting model with reliability factor R=0.069 for 1098 unique reflection over 3σ . Ring A is an 1β-2a-half chair, 5 ring has a highly symmetrical chair conformation, C ring is in a distorted chair conformation and D ring is a 13aenveLope conformation. In the crystal structure, the molecules are packed with a hydrogen bond of 011-H23‥‥03(0.5+x, 1.5-y, 1.0-z) [1.94(9) A of H‥‥0.2.786(9)A of 0‥‥0 and 165(8) ˚ of

• The Journal of the Korea Contents Association
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• v.17 no.11
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• pp.90-101
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• 2017

This study will analyze that the meaning and the characteristic of Information design type advertising. This study research the advertisement and Information with the issue and explore Information design type advertising samples by doing an in-depth analysis with an expert group and an inexpert group. It attracts customers visualizing sensational information and data as information design technique. It can be classified in to Manual type ad, Identity type ad, Data visualizing type ad. The communication formula of it goes through the keywords: Attention, Curation, Study, and these Curation and Study are new steps which didn't exist before in consumer behavior model. Information used in it comes from common sense or storytelling made by imagination, but there is no example of using false information distorting truth. Not exaggeration and falsehood, interesting which based on confidence creates a bond of sympathy: period time.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.55-66
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• 1999

This paper presents an analytical prediction of the hysteresis behavior of reinforced concrete long column with rectangular section under the cyclic loading state. The mechanical characteristic of cracked concrete and reinforcing bar in concrete has been modeled, considering the bond effect between reinforcing bar and concrete, the effect of aggregate interlocking at crack surface and the stiffness degradation after the crack has taken place. The strength increase of concrete due to the lateral confining reinforcement has been also taken into account to model the confined concrete. The formulation of these models for concrete and reinforcing bar has been based on the smeared crack concept that the stress-strain relationship of reinforced concrete element would be defined using the average values. In addition to the material nonlinear properties, the algorithm for large displacement problem that may give an additional deformation has been formulated using total Lagrangian formulation. The analytically predicted behavior was compared with test result and they showed good agreement in overall behavior.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.4
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• pp.111-115
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• 2014

Effect of dynamic electric fields on dielectric breakdown behavior in Cu damascene interconnects was investigated. Among the DC, unipolar, and bipolar pulse conditions, the longest dielectric lifetime is observed under the bipolar condition because backward Cu ion drift occurs when the direction of electric field is changed by 180 degrees and Cu contamination is prohibited as a results. Under the unipolar pulse condition, the dielectric lifetime increases as pulse frequency increases and it exceed the lifetime under DC condition. It suggests that the intrinsic breakdown of dielectrics significantly affect the dielectric breakdown in addition to Cu contamination. As the unipolar pulse width decreases, dielectric bond breakdown is more difficult to occur.