Bridge Resistance Updating Based on the General Particle Simulation Algorithms of Complex Bayesian Formulas

2021 ◽  
Vol 43 ◽  
pp. 111-122
Author(s):  
Xue Ping Fan ◽  
Sen Wang ◽  
Yue Fei Liu
Keyword(s):  
Expectation Maximization ◽  
Probability Model ◽  
Distribution Functions ◽  
Bridge Engineering ◽  
Particle Simulation ◽  
Posteriori Probability ◽  
Resistance Degradation ◽  
Simulation Algorithms ◽  
Existing Bridges ◽  
Bridge Resistance

The existing bridges are subjected to time-variant loading and resistance degradation processes. How to update resistance probability distribution functions with resistance degradation model and proof load effects has become one of the research hotspots in bridge engineering field. To solve with the above issue, this paper proposed the general particle simulation algorithms of complex Bayesian formulas for bridge resistance updating. Firstly, the complex Bayesian formulas for updating resistance probability model are built. For overcoming the difficulty for the analytic calculation of complex Bayesian formulas, the general particle simulation methods are provided to obtain the particles of complex Bayesian formulas; then, with the improved expectation maximization optimization algorithm obtained with the combination of K-MEANS algorithm and Expectation Maximization (EM) algorithm, the above simulated particles can be used to estimate the posteriori probability density functions of resistance probability model; finally, a numerical example is provided to illustrate the feasibility and application of the proposed algorithms.

scholarly journals Population pharmacokinetic modeling of isoniazid, rifampin, and pyrazinamide.

1997 ◽  
Vol 41 (12) ◽  
pp. 2670-2679 ◽  
Author(s):  
C A Peloquin ◽  
G S Jaresko ◽  
C L Yong ◽  
A C Keung ◽  
A E Bulpitt ◽  
...  
Keyword(s):  
Expectation Maximization ◽  
High Performance ◽  
Posteriori Probability ◽  
Maximum A Posteriori ◽  
Population Pharmacokinetic ◽  
A Posteriori ◽  
Population Pharmacokinetic Modeling ◽  
A Posteriori Probability ◽  
Modeling Methods ◽  
Elimination Half

Isoniazid (INH), rifampin (RIF), and pyrazinamide (PZA) are the most important drugs for the treatment of tuberculosis (TB). The pharmacokinetics of all three drugs in the plasma of 24 healthy males were studied as part of a randomized cross-over phase I study of two dosage forms. Subjects ingested single doses of INH at 250 mg, RIF at 600 mg, and PZA at 1,500 mg. Plasma was collected for 36 h and was assayed by high-performance liquid chromatography. The data were analyzed by noncompartmental, iterative two-stage maximum a posteriori probability Bayesian (IT2B) and nonparametric expectation maximization (NPEM) population modeling methods. Fast and slow acetylators of INH had median peak concentrations in plasma (C[max]) of 2.44 and 3.64 microg/ml, respectively, both of which occurred at 1.0 h postdose (time of maximum concentrations of drugs in plasma [T(max)]), with median elimination half-lives (t1/2) of 1.2 and 3.3 h, respectively (by the NPEM method). RIF produced a median C(max) of 11.80 microg/ml, a T(max) of 1.0 h, and a t1/2 of 3.4 h. PZA produced a median C(max) of 28.80 microg/ml, a T(max) of 1.0 h, and a t1/2 of 10.0 h. The pharmacokinetic behaviors of INH, RIF, and PZA were well described by the three methods used. These models can serve as benchmarks for comparison with models for other populations, such as patients with TB or TB with AIDS.

scholarly journals Investigation of Traffic Loading Effects for Different Codes on Medium- and Small-Span Girder Bridges in China

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Qingfei Gao ◽  
Biao Wu ◽  
Jun Li ◽  
Kemeng Cui ◽  
Chuang Xu
Keyword(s):  
Bridge Engineering ◽  
Traffic Load ◽  
Bending Moments ◽  
Original Design ◽  
Traffic Loading ◽  
Simply Supported ◽  
Girder Bridges ◽  
Loading Effects ◽  
Existing Bridges ◽  
Structure Evaluation

With increasing traffic volume, the traffic load grade given by design codes has gradually increased. For new bridges, there is no problem, and the traffic load can be met through the requirements of the new code. However, for existing bridges, there is a lack of uniform standards on whether they can continue to be used. It is not clear whether these bridges will be judged according to the new code or the original design code. The traffic loading effects of different codes on medium- and small-span girder bridges in China are investigated in this study. Three codes are introduced: JTJ 021-89, JTG D60-2004, and JTG D60-2015. Simply supported girder bridges and continuous girder bridges are discussed. The traffic loading effects calculated based on JTG D60-2015 are significantly larger than those calculated based on JTJ 021-89. For simply supported girder bridges, most of the differences range from 20% to 40%, and the maximum value is almost larger than 60%. For continuous girder bridges, most of the differences in the positive bending moments are concentrated in the 20%∼40% range, while the differences in the negative bending moments range from 10% to 20%. Therefore, the differences in traffic loading effects calculated based on various codes cannot be ignored in actual bridge engineering. The conclusion in this study can provide a basis for bridge structure evaluation and life prediction.

A 2-D HMM METHOD FOR OFFLINE HANDWRITTEN CHARACTER RECOGNITION

2001 ◽  
Vol 15 (01) ◽  
pp. 91-105 ◽  
Author(s):  
HEE-SEON PARK ◽  
BONG-KEE SIN ◽  
JONGSUB MOON ◽  
SEONG-WHAN LEE
Keyword(s):  
Random Field ◽  
Character Recognition ◽  
Hidden Markov ◽  
Promising Result ◽  
Transition Probability ◽  
Recognition Rate ◽  
Distribution Functions ◽  
Estimation Methods ◽  
Posteriori Probability ◽  
Training Algorithms

In this paper we consider a hidden Markov mesh random field (HMMRF) for character recognition. The model consists of a "hidden" Markov mesh random field (MMRF) and an overlying probabilistic observation function of the MMRF. Just like the 1-D HMM, the hidden layer is characterized by the initial and the transition probability distributions, and the observation layer is defined by distribution functions for vector-quantized (VQ) observations. The HMMRF-based method consists of two phases: decoding and training. The decoding and the training algorithms are developed using dynamic programming and maximum likelihood estimation methods. To accelerate the computation in both phases, we employed a look-ahead scheme based on maximum marginal it a posteriori probability criterion for third-order HMMRF. Tested on a larget-set handwritten Korean Hangul character database, the model showed a promising result: up to 87.2% recognition rate with 8 state HMMRF and 128 VQ levels.

LIKELIHOOD OF A PARTICULAR ORDER OF GENETIC MARKERS AND THE CONSTRUCTION OF GENETIC MAPS

2008 ◽  
Vol 06 (01) ◽  
pp. 125-162 ◽  
Author(s):  
S. TEWARI ◽  
J. ARNOLD ◽  
S. M. BHANDARKAR
Keyword(s):  
Genetic Markers ◽  
Expectation Maximization ◽  
Goodness Of Fit ◽  
Genomic Sequence ◽  
Probability Model ◽  
Genetic Maps ◽  
Model Framework ◽  
Marker Data ◽  
Chi Squared ◽  
Genetic Interval

We model the recombination process of fungal systems via chromatid exchange in meiosis, which accounts for any type of bivalent configuration in a genetic interval in any specified order of genetic markers, for both random spore and tetrad data. First, a probability model framework is developed for two genes and then generalized for an arbitrary number of genes. Maximum likelihood estimators (MLEs) for both random and tetrad data are developed. It is shown that the MLE of recombination for tetrad data is uniformly more efficient over that from random spore data by a factor of at least 4 usually. The MLE for the generalized probability framework is computed using the expectation-maximization (EM) algorithm. Pearson's chi-squared statistic is computed as a measure of goodness of fit using a product-multinomial setup. We implement our model with genetic marker data on the whole genome of Neurospora crassa. Simulated annealing is used to search for the best order of genetic markers for each chromosome, and the goodness of fit value is evaluated for model assumptions. Inferred map orders are corroborated by genomic sequence, with the exception of linkage groups I, II, and V.

Bridge Safety Quick Test Vehicle Feasibility Development Research

2012 ◽  
Vol 178-181 ◽  
pp. 2401-2404
Author(s):  
Xiao Min Huang ◽  
Jin Bo Song
Keyword(s):  
Capital Investment ◽  
Rapid Development ◽  
Development Trend ◽  
Bridge Engineering ◽  
Bridge Construction ◽  
Health Security ◽  
Bridge Maintenance ◽  
The Future ◽  
Existing Bridges ◽  
Future Work

Bridge construction is the national important foundation construction of bridge engineering, is the relationship between society and economy to coordinate development of lifeline engineering. Bridge construction of rapid development, huge capital investment, the economic society of the prominent role, making it to the bridge's safety, durability, more and more attention. Based on the analysis of detection results of existing bridges, bridge on the future work state of speculation, pointed out the possible development trend for the future to provide advice, bridge maintenance. As the bridge reinforcement and reconstruction to provide accurate and comprehensive data. The results of this study, can be formed quickly, economy of bridge health monitoring technology for bridge health security situation in the initial judgement; through the acquisition of the data of bridge health security archives; acquisition project archives data and webGIS docking platform form a" bridge based on webGIS project archives management system " for the future highway bridge maintenance and strengthening of decision making the corresponding reference. The project also has safety, economy, practical, convenient, and many other characteristics suitable for road and Bridge Health census and safety risk assessment.

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