• Title/Summary/Keyword: analytical study

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Geostationary Orbit Surveillance Using the Unscented Kalman Filter and the Analytical Orbit Model

  • Roh, Kyoung-Min;Park, Eun-Seo;Choi, Byung-Kyu
    • Journal of Astronomy and Space Sciences
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    • v.28 no.3
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    • pp.193-201
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    • 2011
  • A strategy for geostationary orbit (or geostationary earth orbit [GEO]) surveillance based on optical angular observations is presented in this study. For the dynamic model, precise analytical orbit model developed by Lee et al. (1997) is used to improve computation performance and the unscented Kalman filer (UKF) is applied as a real-time filtering method. The UKF is known to perform well under highly nonlinear conditions such as surveillance in this study. The strategy that combines the analytical orbit propagation model and the UKF is tested for various conditions like different level of initial error and different level of measurement noise. The dependencies on observation interval and number of ground station are also tested. The test results shows that the GEO orbit determination based on the UKF and the analytical orbit model can be applied to GEO orbit tracking and surveillance effectively.

Application of fiber element in the assessment of the cyclic loading behavior of RC columns

  • Sadjadi, R.;Kianoush, M.R.
    • Structural Engineering and Mechanics
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    • v.34 no.3
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    • pp.301-317
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    • 2010
  • This paper studies the reliability of an analytical tool for predicting the lateral load-deformation response of RC columns while subjected to lateral cyclic displacements and axial load. The analytical tool in this study is based on a fiber element model implemented into the program DRAIN-2DX (fiber element). The response of RC column under cyclic displacement is defined by the behavior of concrete, and reinforcing steel under general reversed-cyclic loading. A tri-linear stress-strain relationship for the cyclic behavior of steel is proposed and the improvement in the analytical results is studied. This study only considers the behavior of columns with flexural dominant mode of failure. It is concluded that with the implementation of appropriate constitutive material models, the described analytical tools can predict the response of the columns with reasonable accuracy when compared to experimental data.

Computer simulation for dynamic wheel loads of heavy vehicles

  • Kawatani, Mitsuo;Kim, Chul-Woo
    • Structural Engineering and Mechanics
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    • v.12 no.4
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    • pp.409-428
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    • 2001
  • The characteristics of dynamic wheel loads of heavy vehicles running on bridge and rigid surface are investigated by using three-dimensional analytical model. The simulated dynamic wheel loads of vehicles are compared with the experimental results carried out by Road-Vehicles Research Institute of Netherlands Organization for Applied Scientific Research (TNO) to verify the validity of the analytical model. Also another comparison of the analytical result with the experimental one for Umeda Entrance Bridge of Hanshin Expressway in Osaka, Japan, is presented in this study. The agreement between the analytical and experimental results is satisfactory and encouraging the use of the analytical model in practice. Parametric study shows that the dynamic increment factor (DIF) of the bridge and RMS values of dynamic wheel loads are fluctuated according to vehicle speeds and vehicle types as well as roadway roughness conditions. Moreover, there exist strong dominant frequency resemblance between bounce motion of vehicle and bridge response as well as those relations between RMS values of dynamic wheel loads and dynamic increment factor (DIF) of bridges.

A study on analytical methods for polycyclic aromatic hydrocarbons in foods (식품 중 다환방향족탄화수소 분석법 연구)

  • Kim, Yong-Yeon;Shin, Han-Seung
    • Food Science and Industry
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    • v.55 no.1
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    • pp.45-57
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    • 2022
  • This study was proceeded the analytical methods using various analytical instruments for polycyclic aromatic hydrocarbons (PAHs) in food products. Various analytical methods were developed to determine levels of PAHs including benzo[a]pyrene, benzo[a]anthracene, benzo[b]fluoranthene, and chrysene formed in various food products using gas chromatography-mass spectrometry (GC-MS), enzyme-linked immunosorbent assay (ELISA) and raman spectroscopy. Recently, the rapid on-site response for the detection of hazardous substances in food aims to develop an onsite rapid detection of a simplified technical analysis method to reduce the time and cost required for analysis of PAHs. Current PAHs detection methods have been reviewed along with new raman spectroscopy analytical method.

A study on the analytical procedures using artificial intelligence methods

  • Han, In-Goo;Youn, Sung-Jun
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1997.10a
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    • pp.109-112
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    • 1997
  • In this study, we attempt to improve analytical methods in auditing by applying Artificial Intelligence(AI) methods including Artificial Neural Networks(ANN) and Case-Based Reasoning(CBR), and to perform pattern recognition of the investigation signals generated by analytical procedures. Five years of audited financial data from a large-sized firm were used to calculate four commonly applied financial ratios. This exploratory study shows that the use of AI methods to analyze patterns of related fluctuations across numerous financial ratios provides improved performance in recognizing material misstatements within the financial accounts.

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The Study of detailng for concrete reinforcement and Seismic Analysis Method for Underground Reinforced Concrete Box Structures (지하 철근 콘크리트 박스 구조물의 내진해석방법 및 철근 배근 상세에 관한 연구)

  • Lee, Myoung-Soo;Han, Sang-Chel
    • Proceedings of the KSR Conference
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    • 2005.11a
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    • pp.1215-1222
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    • 2005
  • The object of this thesis is an study on detailing for concrete reinforcement and analytical study for seismic behavior of underground reinforced concrete box structures using the established seismic analytical method. Using the established seismic analytical method that has been presented in various documents seismic behavior of buried reinforce concrete box structures is compared. From the comparsion, it is shown that feasibility and detailing detailng for concrete reinforcement and seismic method for seismic analysis of buried reinforced concrete box structures.

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Analysis on Endotoxin Using Analytical Conditions of Optical Density in Metalworking Fluid Sample (금속가공유 시료에서 Optical Density 설정조건에 따른 엔도톡신의 정량)

  • 박동욱;윤충식;박두용;한인영
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2002.04a
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    • pp.44-46
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    • 2002
  • This study was conducted to identify the proper analytical conditions regarding optical density for endotoxin analysis in the workplace using metalworking fludis. Our study found the "onset method" was more accurate than "time to Vmax" Reproducibility and accuracy analyzed by "onset method" was more greater than those by "time to Vmax""0.03"of optical density was the most appropriate analytical condition among onset method. Through this analytical condition, 0.998 of linearity was obtained and recovery rate ranged from 88% to 105% at endotoxin concentration below 5 EU/$m\ell$. No significant difference of endotoxins between "0.03"and "0.05" of optical density was observed from this study. Furthermore, correlation coefficients between them were statistically significant(p<0.01). This study concluded that 0.03”or "0.05" of optical density is used to analyze endotoxin. Of these optical density value, value with higher linearity should be used to analyze endotoxin in environmental samples.

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Standardization of Hippocastani Semen Extract (서양칠엽수종자엑스 기준및시험법 비교 및 규격 설정)

  • Kim, Seung-Hyun;Kim, Dae-Hyun;Park, Jin-Ho;Cho, Chang-Hee;Lee, Jong-Pill;Kang, Shin-Jung;Lee, Mi-Na;Sung, Sang-Hyun
    • Journal of Pharmaceutical Investigation
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    • v.40 no.1
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    • pp.59-61
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    • 2010
  • This study was carried out to establish standard analytical method of Hippocastani Semen extract. Each standard analytical methods were covered for exact and efficient analytical method. Consequently, analytical method of Deutsches Arzneibuch has been adopted for Hippocastani Semen extract. Analytical methods established in this study could be applied to a reasonable and unified quality control of Hippocastani Semen extract.

Analytical study of the failure mode and pullout capacity of suction anchors in clay

  • Liu, Haixiao;Wang, Chen;Zhao, Yanbing
    • Ocean Systems Engineering
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    • v.3 no.2
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    • pp.79-95
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    • 2013
  • Suction anchors are widely adopted in mooring systems. However there are still challenges in predicting the failure mode and ultimate pullout capacity of the anchor. Previously published methods for predicting the inclined pullout capacity of suction anchors are mainly based on experimental data or the FEM analysis. In the present work, an analytical method that is capable of predicting the failure mode and ultimate pullout capacity of the suction anchor in clay under inclined loading is developed. This method is based on a rational mechanical model for suction anchors and the knowledge of the mechanism that the anchor fails in seabed soils. In order to examine the analytical model, the failure angle and pullout capacity of suction anchors from FEM simulation, numerical solution and laboratory tests in uniform and linear cohesive soils are employed to compare with the theoretical predictions and the agreement is satisfactory. An analytical method that can evaluate the optimal position of the attachment point is also proposed in the present study. The present work proves that the failure mode and pullout capacity of suction anchors can be reasonably determined by the developed analytical method.

Comparative Study of Armature Reaction Field Analysis for Tubular Linear Machine with Axially Magnetized Single-sided and Double-sided Permanent Magnet Based on Analytical Field Calculations

  • Shin, Kyung-Hun;Park, Min-Gyu;Cho, Han-Wook;Choi, Jang-Young
    • Journal of Magnetics
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    • v.20 no.1
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    • pp.79-85
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    • 2015
  • This paper presents a comparative study of a Tubular Linear Machine (TLM) with an Axially Magnetized Single-sided Permanent Magnet (AMSPM) and an Axially Magnetized Double-sided Permanent Magnet (AMDPM) based on analytical field calculations. Using a two-dimensional (2-D) polar coordinate system and a magnetic vector potential, analytical solutions for the flux density produced by the stator windings are derived. This technique is significant for the design and control implementation of electromagnetic machines. The field solution is obtained by solving Maxwell's equations in the simplified boundary value problem consisting of the air gap and coil. These analytical solutions are then used to estimate the self and mutual inductances. Two different types of machine are used to verify the validity of these model simplifications, and the analytical results are compared to results obtained using the finite element method (FEM) and experimental measurement.