• Title/Summary/Keyword: 3-D non-linear modeling

Search Result 52, Processing Time 0.028 seconds

Behavior and modeling of RC beams strengthened with NSM-steel technique

  • Md. Akter Hosen;Khalid Ahmed Al Kaaf;A.B.M. Saiful Islam;Mohd Zamin Jumaat;Zaheer Abbas Kazmi
    • Structural Engineering and Mechanics
    • /
    • v.88 no.1
    • /
    • pp.67-81
    • /
    • 2023
  • The reinforced concrete (RC) structures might need strengthening or upgradation due to adverse environmental conditions, design defects, modification requirements, and to prolong the expected lifespan. The RC beams have been efficiently strengthened using the near surface mounted (NSM) approach over the externally bonded reinforcing (EBR) system. In this study, the performance of RC beam elements strengthened with NSM-steel rebars was investigated using an experimental program and nonlinear finite element modeling (FEM). Nine medium-sized, rectangular cross-section RC beams total in number made up for the experimental evaluation. The beams strengthened with varying percentages of NSM reinforcement, and the number of grooves was assessed in four-point bending experiments up to failure. Based on the experimental evaluation, the load-displacement response, crack features, and failure modes of the strengthened beams were recorded and considered. According to the experimental findings, NSM steel greatly improved the flexural strength (up to about 84%) and stiffness of RC beams. The flexural response of the tested beams was simulated using a 3D non-linear finite element (FE) model. The findings of the experiments and the numerical analysis showed good agreement. The effect of the NSM groove and reinforcement on the structural response was then assessed parametrically.

IP Modeling and Inversion Using Complex Resistivity (복소 전기비저항을 이용한 IP 탐사 모델링 및 역산)

  • Son, Jeong-Sul;Kim, Junhg-Ho;Yi, Myeong-Jong
    • Geophysics and Geophysical Exploration
    • /
    • v.10 no.2
    • /
    • pp.138-146
    • /
    • 2007
  • This paper describes 2.5D induced polarization (IP) modeling and inversion algorithms using complex resistivity. The complex resistivity method has merits for acquiring more valuable information about hydraulic parameters and pore fluid than the conventional IP methods. The IP modeling and inversion algorithms are developed by allowing complex arithmetic in existing DC modeling and inversion algorithms. The IP modeling and inversion algorithms use a 2.5D DC finite-element algorithm and a damped least-squares method with smoothness constraints, respectively. The accuracy of the IP modeling algorithm is verified by comparing its responses of two synthetic models with two different approaches: linear filtering for a three-layer model and an integral equation method for a 3D model. Results from these methods are well matched to each other. The inversion algorithm is validated by a synthetic example which has two anomalous bodies, one is more conductive but non-polarizable than the background, and the other is polarizable but has the same resistivity as the background. From the inverted section, we can cleary identify each anomalous body with different locations. Furthermore, in order to verify its efficiency to the real filed example, we apply the inversion algorithm to another three-layer model which includes phase anomaly in the second layer.

Current Conservation Factors for Consistent One-Dimensional Neutronics Modeling

  • Lee, Kibog;Joo, Han-Gyu;Cho, Byung-Oh;Zee, Sung-Quun
    • Nuclear Engineering and Technology
    • /
    • v.32 no.3
    • /
    • pp.235-243
    • /
    • 2000
  • A one-dimensional neutronics formulation is established within the framework of the nonlinear analytic nodal method such that it can result in consistent one-dimensional models that produce the same axial information as their corresponding reference three-dimension81 models. Consistency is achieved by conserving axial interface currents as well as the planar reaction rates of the three-dimensional case. For current conservation, flux discontinuity is introduced in the solution of the two-node problem. The degree of discontinuity, named the current conservation factor, is determined such that the surface averaged axial current of the reference three-dimensional case can be retrieved from the two-node calculation involving the radially collapsed group constants and the discontinuity factor. The current conservation factors are derived from the analytic nodal method and various core configurations are analyzed to show that the errors in K-eff and power distributions can be reduced by a order of magnitude by the use of the current conservation factor with no significant computational overhead.

  • PDF

Receiver Operating Characteristic Curve Analysis of SEER Medulloblastoma and Primitive Neuroectodermal Tumor (PNET) Outcome Data: Identification and Optimization of Predictive Models

  • Cheung, Min Rex
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.16
    • /
    • pp.6781-6785
    • /
    • 2014
  • Purpose: This study used receiver operating characteristic curves to analyze Surveillance, Epidemiology and End Results (SEER) medulloblastoma (MB) and primitive neuroectodermal tumor (PNET) outcome data. The aim of this study was to identify and optimize predictive outcome models. Materials and Methods: Patients diagnosed from 1973 to 2009 were selected for analysis of socio-economic, staging and treatment factors available in the SEER database for MB and PNET. For the risk modeling, each factor was fitted by a generalized linear model to predict the outcome (brain cancer specific death, yes/no). The area under the receiver operating characteristic curve (ROC) was computed. Similar strata were combined to construct the most parsimonious models. A Monte Carlo algorithm was used to estimate the modeling errors. Results: There were 3,702 patients included in this study. The mean follow up time (S.D.) was 73.7 (86.2) months. Some 40% of the patients were female and the mean (S.D.) age was 16.5 (16.6) years. There were more adult MB/PNET patients listed from SEER data than pediatric and young adult patients. Only 12% of patients were staged. The SEER staging has the highest ROC (S.D.) area of 0.55 (0.05) among the factors tested. We simplified the 3-layered risk levels (local, regional, distant) to a simpler non-metastatic (I and II) versus metastatic (III) model. The ROC area (S.D.) of the 2-tiered model was 0.57 (0.04). Conclusions: ROC analysis optimized the most predictive SEER staging model. The high under staging rate may have prevented patients from selecting definitive radiotherapy after surgery.

3D surface Reconstruction of Moving Object Using Multi-Laser Stripes Irradiation (멀티 레이저 라인 조사를 이용한 비등속 이동물체의 3차원 형상 복원)

  • Yi, Young-Youl;Ye, Soo-Young;Nam, Ki-Gon
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.44 no.2 s.314
    • /
    • pp.144-152
    • /
    • 2007
  • We propose a 3D modeling method for surface inspection of non-linear moving object. The laser lines reflect the surface curvature. We can acquire 3D surface information by analyzing projected laser lines on object. ill this paper, we use multi-line laser to make use of robust of single stripe method and high speed of single frame. Binarization and channel edge extraction method were used for robust laser line extraction. A new labeling method was used for laser line labeling. We acquired sink information between each 3D reconstructed frame by feature point matching, and registered each frame to one whole image. We verified the superiority of proposed method by applying it to container damage inspection system.

Optimization of Predictors of Ewing Sarcoma Cause-specific Survival: A Population Study

  • Cheung, Min Rex
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.10
    • /
    • pp.4143-4145
    • /
    • 2014
  • Background: This study used receiver operating characteristic curve to analyze Surveillance, Epidemiology and End Results (SEER) Ewing sarcoma (ES) outcome data. The aim of this study was to identify and optimize ES-specific survival prediction models and sources of survival disparities. Materials and Methods: This study analyzed socio-economic, staging and treatment factors available in the SEER database for ES. 1844 patients diagnosed between 1973-2009 were used for this study. For the risk modeling, each factor was fitted by a Generalized Linear Model to predict the outcome (bone and joint specific death, yes/no). The area under the receiver operating characteristic curve (ROC) was computed. Similar strata were combined to construct the most parsimonious models. Results: The mean follow up time (S.D.) was 74.48 (89.66) months. 36% of the patients were female. The mean (S.D.) age was 18.7 (12) years. The SEER staging has the highest ROC (S.D.) area of 0.616 (0.032) among the factors tested. We simplified the 4-layered risk levels (local, regional, distant, un-staged) to a simpler non-metastatic (I and II) versus metastatic (III) versus un-staged model. The ROC area (S.D.) of the 3-tiered model was 0.612 (0.008). Several other biologic factors were also predictive of ES-specific survival, but not the socio-economic factors tested here. Conclusions: ROC analysis measured and optimized the performance of ES survival prediction models. Optimized models will provide a more efficient way to stratify patients for clinical trials.

Maneuvering Target Tracking With 3D Variable Turn Model and Kinematic Constraint (3D 가변 선회 모델 및 기구학적 구속조건을 사용한 기동표적 추적)

  • Kim, Lamsu;Lee, Dongwoo;Bang, Hyochoong
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.48 no.11
    • /
    • pp.881-888
    • /
    • 2020
  • In this paper, research on estimation of states of a target of interest using Line Of Sight(LOS) angle measurement is performed. Target's position, velocity, and acceleration are chosen to be the states of interests. The LOS measurement is known to be highly non-linear, making target dynamic modeling hard to be implemented into a filter. To solve this issue, the Pseudomeasurement equation was applied to the LOS measurement equation. With the help of this equation, 3D variable turn target dynamic model is applied to the filter model. For better performance, Kinematic Constraint is also implemented into the filter model. As for the filter, Bias Compensation Pseudomeasurement Filter (BCPMF) is used which is known for its robustness to initial conditions. Moreover, Two-Stage Kalman Filter (TSKF) form was also implemented to benefit from the parallel computation. As a result, TBCPMF 3DVT-KC is proposed and simulated to assess performance.

UTLIZATION OF FUZZY AND VOLETTRA ALGORITHM FOR 3D BATHYMETRY SIMULATION FROM TOPSAR POLARISED DATA

  • Marghany, Maged;Hussien, Mohd. Lokman
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.432-434
    • /
    • 2003
  • The main objective of this research is to utilize the parallel Fuzzy arithmetic for constructing ocean bathymetry from polarized remote sensing data such as TOPSAR image. In doing so, the parallel library for Fuzzy arithmetic has been developed. Three- dimensional surface modeling consisted of Volettra model, non-linear model which construct a global topological structure between the data points, used to support an approximation of real surface. The output of the parallel library was a digital terrain model for bathymetry along the coastal waters of Kuala Terengganu Malaysia. This paper describes the principles behind the Fuzzy algorithm, indicates for what type of application it might be useful, notes on the accuracy and gives an example of an application.

  • PDF

Strain Recovery Analysis of Non-uniform Composite Beam with Arbitrary Cross-section and Material Distribution Using VABS (VABS를 이용한 임의의 단면과 재료 분포를 가진 비균일 복합재료 보의 변형률 복원 해석)

  • Jang, Jun Hwan;Ahn, Sang Ho
    • Composites Research
    • /
    • v.28 no.4
    • /
    • pp.204-211
    • /
    • 2015
  • This paper presents a theory related to a two-dimensional linear cross-sectional analysis, recovery relationship and a one-dimensional nonlinear beam analysis for composite wing structure with initial twist. Using VABS including a related theory, the design process of the composite rotor blade has been described. Cross-sectional analysis was performed at cutting point including all the details of geometry and material. Stiffness matrix and mass matrix were linked to each section to make 1D beam model. The 3D strain distributions within the structure were recovered based on the global behavior of the 1D beam analysis and visualize numerical results.

Robust design on the arrangement of a sail and control planes for improvement of underwater Vehicle's maneuverability

  • Wu, Sheng-Ju;Lin, Chun-Cheng;Liu, Tsung-Lung;Su, I-Hsuan
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.12 no.1
    • /
    • pp.617-635
    • /
    • 2020
  • The purpose of this study is to discuss how to improve the maneuverability of lifting and diving for underwater vehicle's vertical motion. Therefore, to solve these problems, applied the 3-D numerical simulation, Taguchi's Design of Experiment (DOE), and intelligent parameter design methods, etc. We planned four steps as follows: firstly, we applied the 2-D flow simulation with NACA series, and then through the Taguchi's dynamic method to analyze the sensitivity (β). Secondly, take the data of pitching torque and total resistance from the Taguchi orthogonal array (L9), the ignal-to-noise ratio (SNR), and analysis each factorial contribution by ANOVA. Thirdly, used Radial Basis Function Network (RBFN) method to train the non-linear meta-modeling and found out the best factorial combination by Particle Swarm Optimization (PSO) and Weighted Percentage Reduction of Quality Loss (WPRQL). Finally, the application of the above methods gives the global optimum for multi-quality characteristics and the robust design configuration, including L/D is 9.4:1, the foreplane on the hull (Bow-2), and position of the sail is 0.25 Ls from the bow. The result shows that the total quality is improved by 86.03% in comparison with the original design.