• Title/Summary/Keyword: Complex Loading

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Data Sampling-based Angular Space Partitioning for Parallel Skyline Query Processing (데이터 샘플링을 통한 각 기반 공간 분할 병렬 스카이라인 질의처리 기법)

  • Chung, Jaehwa
    • The Journal of Korean Association of Computer Education
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    • v.18 no.5
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    • pp.63-70
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    • 2015
  • In the environment that the complex conditions need to be satisfied, skyline query have been applied to various field. To processing a skyline query in centralized scheme, several techniques have been suggested and recently map/reduce platform based approaches has been proposed which divides data space into multiple partitions for the vast volume of multidimensional data. However, the performances of these approaches are fluctuated due to the uneven data loading between servers and redundant tasks. Motivated by these issues, this paper suggests a novel technique called MR-DEAP which solves the uneven data loading using the random sampling. The experimental result gains the proposed MR-DEAP outperforms MR-Angular and MR-BNL scheme.

Dynamic field monitoring data analysis of an ancient wooden building in seismic and operational environments

  • Lyu, Mengning;Zhu, Xinqun;Yang, Qingshan
    • Earthquakes and Structures
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    • v.11 no.6
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    • pp.1043-1060
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    • 2016
  • The engineering background of this article is an ancient wooden building with extremely high historic and cultural values in Tibet. A full understanding of the dynamic behaviour of this historic building under in-service environments is the basis to assess the condition of the structure, especially its responses to earthquake, environmental and operational loading. A dynamic monitoring system has been installed in the building for over one year and the large amounts of high quality data have been obtained. The paper aims at studying the dynamic behaviour of the wooden building in seismic and operational conditions using the field monitoring data. Specifically the effects of earthquake and crowd loading on the structure's dynamic response are investigated. The monitoring data are decomposed into principal components using the Singular Spectrum Analysis (SSA) technique. The relationship between the average acceleration amplitude and frequencies of the principle components and operational conditions has been discussed. One main contribution is to understand the health condition of complex ancient building based on large databases collected on the field.

Characterization of Methanol-Water and Acetonitrile-Water Mixtures Using Iterative Target Transform Factor Analysis on Near Infrared Absorption Spectra (근적외선흡광스픽트럼에 대한 반복목표변환인자분석에 의한 메탄올-물 혼합액 및 아세토니트릴 -물 혼합액의 특성 확인)

  • 박영주;조정환
    • YAKHAK HOEJI
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    • v.48 no.1
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    • pp.6-12
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    • 2004
  • Near-infrared spectra of methanol-water mixtures and acetonitrile-water mixtures were acquired to find interactions between solvents widely used for reverse-phase liquid chromatography. Mixtures were prepared to give a series of increasing mole fractions of methanol or acetonitrile in water. Data matrices of acquired spectra were analyzed to determine the proper number of principal components of each mixture system using Malinowski's factor indicator function. Initial guess of score matrix and loading matrix were calculated by nonlinear iterative partial least squares (NIPALS) algorithm for faster computation. Iterative target transform factor analysis (ITTFA) was applied to convert the initial estimation of score matrix to true concentration profile and loading matrix to pure spectra of pure components of the mixtures. In case of methanol-water the number of principal components was found to be 4 and those initial guess of factors were converted to the pure spectra of water methanol and two kinds of complexes. In case of acetonitrile-water the number of pure components of the mixtures was found to be 3 and the pure spectrum of acetonitrile-water complex was found. The nonlinear characteristics of concentration profiles of complexes in the solvent mixtures may give a good criteria in understanding their elution characteristics in reverse-phase liquid chromatogrsphy.

Enhancement of the buckling strength of glass beams by means of lateral restraints

  • Belis, J.;Impe, R. Van;Lagae, G.;Vanlaere, W.
    • Structural Engineering and Mechanics
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    • v.15 no.5
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    • pp.495-511
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    • 2003
  • New material applications and transparency are desired by contemporary architects. Its superb transparency and high strength make glass a very suitable building material -in spite of its brittleness- even for primary load bearing structures. Currently we will focus on load bearing glass beams, subjected to different loading types. Since glass beams have a very slender, rectangular cross section, they are sensitive to lateral torsional buckling. Glass beams fail under a critical buckling load at stresses that lie far below the theoretical simple bending strength, due to the complex combination of torsion and out-of-plane bending, which characterises the instability phenomenon. The critical load can be increased considerably by preventing the upper rim from moving out of the beam's plane. Different boundary conditions are examined for different loading types. The load carrying capacity of glass beams can be increased three times and more using relatively simple, cheap lateral restraints.

Simulations of PEC columns with equivalent steel section under gravity loading

  • Begum, Mahbuba;Ghosh, Debaroti
    • Steel and Composite Structures
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    • v.16 no.3
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    • pp.305-323
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    • 2014
  • This paper presents numerical simulations of partially encased composite columns (PEC) with equivalent steel sections. The composite section of PEC column consists of thin walled welded H- shaped steel section with transverse links provided at regular intervals between the flanges. Concrete is poured in the space between the flanges and the web plate. Most of the structural analysis and design software do not handle such composite members due to highly nonlinear material behavior of concrete as well as due to the complex interfacial behaviour of steel and concrete. In this paper an attempt has been made to replace the steel concrete composite section by an equivalent steel section which can be easily incorporated in the design and analysis software. The methodology used for the formulation of the equivalent steel section is described briefly in the paper. Finite element analysis is conducted using the equivalent steel section of partially encased composite columns tested under concentric gravity loading. The reference test columns are obtained from the literature, encompassing a variety of geometric and material properties. The finite element simulations of the composite columns with equivalent steel sections are found to predict the experimental behaviour of partially encased composite columns with very good accuracy.

MODELING OF NONLINEAR CYCLIC LOAD BEHAVIOR OF I-SHAPED COMPOSITE STEEL-CONCRETE SHEAR WALLS OF NUCLEAR POWER PLANTS

  • Ali, Ahmer;Kim, Dookie;Cho, Sung Gook
    • Nuclear Engineering and Technology
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    • v.45 no.1
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    • pp.89-98
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    • 2013
  • In recent years steel-concrete composite shear walls have been widely used in enormous high-rise buildings. Due to high strength and ductility, enhanced stiffness, stable cycle characteristics and large energy absorption, such walls can be adopted in the auxiliary building; surrounding the reactor containment structure of nuclear power plants to resist lateral forces induced by heavy winds and severe earthquakes. This paper demonstrates a set of nonlinear numerical studies on I-shaped composite steel-concrete shear walls of the nuclear power plants subjected to reverse cyclic loading. A three-dimensional finite element model is developed using ABAQUS by emphasizing on constitutive material modeling and element type to represent the real physical behavior of complex shear wall structures. The analysis escalates with parametric variation in steel thickness sandwiching the stipulated amount of concrete panels. Modeling details of structural components, contact conditions between steel and concrete, associated boundary conditions and constitutive relationships for the cyclic loading are explained. Later, the load versus displacement curves, peak load and ultimate strength values, hysteretic characteristics and deflection profiles are verified with experimental data. The convergence of the numerical outcomes has been discussed to conclude the remarks.

Preparation and Evaluation of Phenylpropanolamine HCI by Complexation with Cation Exchange Resin (양이온교환수지복합체에 의한 페닐프로판올아민염산염의 제조 및 평가)

  • Kim, In-Kyu;Lee, Kyung-Tae;Seo, Seong-Hoon;Kim, Chong-Kook;Kim, Dong-Hyun;Rho, Young-Soo
    • Journal of Pharmaceutical Investigation
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    • v.29 no.4
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    • pp.309-313
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    • 1999
  • This study was prepared to develop the sustained release dosage form of phenylpropanolamine hydrochloride (PPA) by complexation with cation exchange resin(CER). The PPA-CER complex was confirmed by differential scanning calorimetry(DSC) thennogram, indicating a relative shift of an endometric peak of PPA to higher temperature. The loading efficiency was increased as the amount of PPA was increased as well as the time of fractional exchange was advanced as the temperatures were increased. Loading efficiency, fractional exchange, reaction rate constant and activation energy were highly dependent on the temperature and drug : resin ratio. The optimal ratio of PPA and resin was estimated to be 10: 10 for the sustained release.

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Anaerobic digestion of food waste to methane at various organic loading rates (OLRs) and hydraulic retention times (HRTs): Thermophilic vs. mesophilic regimes

  • Kumar, Gopalakrishnan;Sivagurunathan, Periyasamy;Park, Jong-Hun;Kim, Sang-Hyoun
    • Environmental Engineering Research
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    • v.21 no.1
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    • pp.69-73
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    • 2016
  • Generation of food waste is a serious issue that needs to be addressed worldwide. Developing suitable treatment methods while generating energy (methane) is a common practice for sustainable treatment of waste. In this study, methane generation by food waste was investigated in mesophilic and thermophilic regimes at various hydraulic retention times (HRTs) and organic loading rates (OLR). In temperature regimes, influent concentrations and HRTs ranged from 30 to 110 g COD/L and 18 to 30 days, respectively, which corresponding to an OLR of 1.0 to $6.1kg\;COD/m^3-d$. Better methane production and organic removal was observed under thermophilic conditions because of the enhanced hydrolysis of complex polymers and microbial activity at higher temperature. The peak methane productivities attained in thermophilic and mesophilic regimes were 1.30 and $0.99m^3/m^3-d$, respectively. The maximum methane yields were achieved at 50 g COD/L and HRT of 24 d in both cases, and the values were 264 and $221m^3/ton$ COD, respectively. The results of this study will facilitate the development of sustainable methane production technologies using food waste as a feedstock.

Quantitative impact response analysis of reinforced concrete beam using the Smoothed Particle Hydrodynamics (SPH) method

  • Mokhatar, S.N.;Sonoda, Y.;Kueh, A.B.H.;Jaini, Z.M.
    • Structural Engineering and Mechanics
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    • v.56 no.6
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    • pp.917-938
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    • 2015
  • The nonlinear numerical analysis of the impact response of reinforced concrete/mortar beam incorporated with the updated Lagrangian method, namely the Smoothed Particle Hydrodynamics (SPH) is carried out in this study. The analysis includes the simulation of the effects of high mass low velocity impact load falling on beam structures. Three material models to describe the localized failure of structural elements are: (1) linear pressure-sensitive yield criteria (Drucker-Prager type) in the pre-peak regime for the concrete/mortar meanwhile, the shear strain energy criterion (Von Mises) is applied for the steel reinforcement (2) nonlinear hardening law by means of modified linear Drucker-Prager envelope by employing the plane cap surface to simulate the irreversible plastic behavior of concrete/mortar (3) implementation of linear and nonlinear softening in tension and compression regions, respectively, to express the complex behavior of concrete material during short time loading condition. Validation upon existing experimental test results is conducted, from which the impact behavior of concrete beams are best described using the SPH model adopting an average velocity and erosion algorithm, where instability in terms of numerical fragmentation is reduced considerably.

Detection of Mitochondrial Reactive Oxygen Species in Living Rat Trigeminal Caudal Neurons

  • Lee, Hae In;Chun, Sang Woo
    • International Journal of Oral Biology
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    • v.40 no.2
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    • pp.103-109
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    • 2015
  • Growing evidence suggests that mitochondrial reactive oxygen species (ROS) are involved in various pain states. This study was performed to investigate whether ROS-induced changes in neuronal excitability in trigeminal subnucleus caudalis are related to ROS generation in mitochondria. Confocal scanning laser microscopy was used to measure ROS-induced fluorescence intensity in live rat trigeminal caudalis slices. The ROS level increased during the perfusion of malate, a mitochondrial substrate, after loading of 2',7'-dichlorofluorescin diacetate ($H_2DCF-DA$), an indicator of the intracellular ROS; the ROS level recovered to the control condition after washout. When pre-treated with phenyl N-tert-butylnitrone (PBN) and 4-hydroxy-2,2,6,6-tetramethylpiperidene-1-oxyl (TEMPOL), malate-induced increase of ROS level was suppressed. To identify the direct relation between elevated ROS levels and mitochondria, we applied the malate after double-loading of $H_2DCF-DA$ and chloromethyl-X-rosamine (CMXRos; MitoTracker Red), which is a mitochondria-specific fluorescent probe. As a result, increase of both intracellular ROS and mitochondrial ROS were observed simultaneously. This study demonstrated that elevated ROS in trigeminal subnucleus caudalis neuron can be induced through mitochondrial-ROS pathway, primarily by the leakage of ROS from the mitochondrial electron transport chain.