• Structural Engineering and Mechanics
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• v.54 no.2
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• pp.305-317
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• 2015

Optimal sensor placement (OSP) is an integral component in the design of an effective structural health monitoring (SHM) system. This paper describes the implementation of a novel collaborative-climb monkey algorithm (CMA), which combines the artificial fish swarm algorithm (AFSA) with the monkey algorithm (MA), as a strategy for the optimal placement of a predefined number of sensors. Different from the original MA, the dual-structure coding method is adopted for the representation of design variables. The collaborative-climb process that can make the full use of the monkeys' experiences to guide the movement is proposed and incorporated in the CMA to speed up the search efficiency of the algorithm. The effectiveness of the proposed algorithm is demonstrated by a numerical example with a high-rise structure. The results show that the proposed CMA algorithm can provide a robust design for sensor networks, which exhibits superior convergence characteristics when compared to the original MA using the dual-structure coding method.

• Structural Engineering and Mechanics
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• v.19 no.3
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• pp.261-279
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• 2005

The hot spot stress approach is usually adopted in the fatigue design and analysis of tubular welded joints. To apply the hot spot stress approach for fatigue evaluation of long span suspension bridges, the FEM is used to determine the hot spot stress of critical fatigue location. Using the local finite element models of the Tsing Ma Bridge, typical joints are developed and the stress concentration factors are determined. As a case for study, the calculated stress concentration factor is combined with the nominal representative stress block cycle to obtain the representative hot spot stress range cycle block under traffic loading from online health monitoring system. A comparison is made between the nominal stress approach and the hot spot stress approach for fatigue life evaluation of the Tsing Ma Bridge. The comparison result shows that the nominal stress approach cannot consider the most critical stress of the fatigue damage location and the hot spot stress approach is more appropriate for fatigue evaluation.

• Korean Journal of Remote Sensing
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• v.35 no.1
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• pp.15-28
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• 2019

By applying the method of SAR interferometry to X-band synthetic aperture radar (SAR) image of COSMO-SkyMed, detailed motion patterns of five glaciers in the Parlung Zangbo River basin, Tibetan Plateau, in January 2010 have been derived. The results indicate that flow patterns are generally constrained by the valley geometry and terrain complexity. The maximum of $123.9ma^{-1}$ is observed on glacier No.1 and the minimum of $39.4ma^{-1}$ is found on glacier No.3. The mean values of five glaciers are between 22.9 and $98.2ma^{-1}$. Glaciers No.1, No.2, No.4 and No.5 exhibit high velocities in their upper sections with big slope and low velocities in the lower sections. A moraine lake accelerates the speed of mass exchange leading to a fast flow at the terminal of glacier No.3. These glaciers generally move along the direction of decreased elevation and present a macroscopic illustration of the motion from the northwest to the southeast. The accuracy of DEM and registration conditions of DEM-simulated terrain phases has certain effects on calculations of glacier flow direction and velocity. The error field is relatively fragmented in areas inconsistent with the main flow line of the glaciers, and the shape and uniformity of glacier are directly related to the continuous distribution of flow velocity errors.

• Genomics & Informatics
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• v.17 no.2
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• pp.20.1-20.5
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• 2019

Entity normalization, or entity linking in the general domain, is an information extraction task that aims to annotate/bind multiple words/expressions in raw text with semantic references, such as concepts of an ontology. An ontology consists minimally of a formally organized vocabulary or hierarchy of terms, which captures knowledge of a domain. Presently, machine-learning methods, often coupled with distributional representations, achieve good performance. However, these require large training datasets, which are not always available, especially for tasks in specialized domains. CONTES (CONcept-TErm System) is a supervised method that addresses entity normalization with ontology concepts using small training datasets. CONTES has some limitations, such as it does not scale well with very large ontologies, it tends to overgeneralize predictions, and it lacks valid representations for the out-of-vocabulary words. Here, we propose to assess different methods to reduce the dimensionality in the representation of the ontology. We also propose to calibrate parameters in order to make the predictions more accurate, and to address the problem of out-of-vocabulary words, with a specific method.

• Applied Chemistry
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• v.15 no.1
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• pp.21-24
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• 2011

A sensitive silver nanoparticles (Ag NPs) enhanced chemiluminescence (CL) method is reported for the determination of mandelic acid (MA). This method is based on the luminol-KIO₄ system catalyzed by Ag NPs to produce CL spectra. Prepared Ag NPs were characterized by UV-visible spectra and TEM image. Under optimal condition, CL spectra of the system were responded linearly with the concentration of MA in the range of 2.5×10^-9 to 2.0×10^-8 mol L^-1 (r=0.9989) with a detection limit of 1.2×10^-10 mol L^-1. The relative standard deviation of 1.0×10^-7 mol L^-1 MA was found 1.45 (n=9).

• Journal of the Korean Applied Science and Technology
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• v.12 no.1
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• pp.69-79
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• 1995

Ham, sausage and bacon were treated with common household processing techniques including refrigerated storage(0, 14, 28 days) and cooking(pan-frying, microwaving, boiling). Lipid oxidation was evaluated by measuring fatty acid composition, malonaldehyde(MA), TBA values and by measuring fluorescent products. Major fatty acid composition were oleic acid and followed respectively palmitic acid, stearic acid, linoleic acid, linolenic acid. There was no significant difference in fatty acid composition by cooking method but there was a tendency of being increased of unsaturated fatty acid during 28days storage. Ma, TBA and fluorescent products showed a tendency of being increased continually according to storage days rather than cooking method.

• Analytical Science and Technology
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• v.31 no.4
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• pp.161-170
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• 2018

The epidemic of disorders associated with synthetic stimulants, such as methamphetamine (MA) and amphetamine (AP), is a health, social, legal, and financial problem. Owing to the high potential of their abuse and addiction, reliable analytical methods are required to detect and identify MA, AP, and their metabolites in biological samples. Thus, a dilute-and-shoot liquid chromatography-tandem mass spectrophotometry (LC-MS/MS) was developed for simultaneous determination of MA, 4-hydroxymethamphetamine (4HMA), AP, and 4-hydroxyamphetamine (4HA) in urine. Urine sample ($100{\mu}L$) was mixed with $50{\mu}L$ of mobile phase consisting of 0.4 % formic acid and methanol and $50{\mu}L$ of working internal-standard solution. Aliquots of $8{\mu}L$ diluted urine was injected into the LC-MS/MS system. For all analytes, chromatographic separation was performed using a C18 reversed-phase column with gradient elution and a total run time of 5 min. The identification and quantification were performed by multiple reaction monitoring (MRM). Linear least-squares regression was conducted to generate a calibration curve, with $1/x^2$ as the weighting factor. The linear ranges were 2.0-200, 1.0-800, and 10-2500 ng/mL for 4HA and 4HMA, AP, and MA, respectively. The inter- and intraday precisions were within 6.6 %, whereas the inter- and intraday accuracies ranged from -14.9 to 11.3 %. The low limits of quantification were 2.0 ng/mL (4HA and 4HMA), 1.0 ng/mL (AP), and 10 ng/mL (MA). The proposed method exhibited satisfactory selectivity, dilution integrity, matrix effect, and stability, which are required for validation. Moreover, the purification efficiency of high-speed centrifugation was clearly higher than 6-15 % for QC samples (n=5), which was higher than that of the membrane-filtration method. The applicability of the proposed method was tested by forensic analysis of urine samples from drug abusers.

• Polymer(Korea)
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• v.37 no.6
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• pp.744-752
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• 2013

The miscibility between poly(L-lactide) (PLLA) and poly(methyl methacrylate) (PMMA) was investigated using thermal analyses for the purpose of developing birefringence-free material at oriented state. The effect of methyl acrylate (MA) units as comonomer of PMMA on the miscibility was also studied. All the blends prepared in this study show composition-dependent single $T_g$'s between those of blend components and high transparency over the visible region, indicating the miscibility at molecular level and no discernible effect of MA units on it. No phase separation was observed at elevated temperature of $280^{\circ}C$, higher than the degradation of PLLA and PMMA. The interaction energy density in PLLA/PMMA blends with 17 mol% of MA was measured to be $-0.74J/cm^3$ from the equilibrium melting temperature depression based on the Hoffman-Weeks method. The blends show zero-${\Delta}$n behavior at a specific mixing ratio and the drawing ratio of 3 due to compensation of intrinsic orientation birefringence. Birefringence dispersion of PLLA/PMMA5 blends was also measured to examine the possibility for quarter-wave plates or polarizer protective films.

• Journal of Marine Life Science
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• v.9 no.1
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• pp.22-32
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• 2024

The purpose of this study was to determine the effect of external biologger attachment methods on the blood parameters and attachment efficiency of spotted sea bass Lateolabrax maculatus (mean body weight 2630.8 g). The fish were tagged using four different external attachment methods with dummy biologgers: no attachment (control), anchor attachment (AA), monofilament attachment (MA), and silicon tube attachment (SA), each with triplicates. Blood indices and biologger attachment efficiency were assessed on days 1, 7, 14, 28, 56, and 84 after attachment. The concentrations of hematocrit, Na⁺, Cl^-, glutamic pyruvic transaminase and total protein, and the activity of superoxide dismutase in blood were not affected by the external attachment method of biologger. The concentrations of glutamic oxaloacetic transaminase (day 1 of attachment), hemoglobin (day 56) and total cholesterol (day 56 and 84) in AA group, the concentrations of glucose and cortisol (day 14) and total cholesterol (day 84) in MA group showed significantly higher than those of control (p<0.05). During the experiment period, the SA group had no differences from the control in all blood properties. The biologger attachment efficiencies of the AA, MA, and SA groups after 84 days were 0.0%, 33.3%, and 100.0%, respectively. These results indicate that the optimum external biologger attachment method under our experimental conditions is SA type.

• Journal of the Korean Magnetics Society
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• v.18 no.5
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• pp.163-167
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• 2008

The electronic structure and magnetism of superlattice systems consisted of Heusler compound $Co_2MnSi$ (CMS) and zinc-blende MnAs (MA) are investigated by means of the all-electron full potential linearized augmented plane wave method within the generalized gradient approximation. Four superlattice systems are considered, that is CMS(m)/MA(n), where m and n, being either 2 or 4, denote the number of alternatingly arrayed layers of the compounds in a superlattice along [001] direction. From the calculated total magnetic moments as well as the total density of states, it is found that neither of the four systems is half-metallic. It is also found that the Mn atoms are antiferromagnetically coupled in the systems of CMS2/MA2 and CMS2/MA4. The total and atom-resolved density of states of the four superlattices are compared with those of the bulk $Co_2MnSi$ and MnAs, and the influences of the change in the systems symmetry on the magnetism and half-metallicity are discussed.