Chapter 3 Linear State Function Observers

This paper deals with the right to property in general terms from its source in Roman law, which is the starting point for all subsequent legal systems. As a result of this, the acquisition of property rights is handled from the historical point of view, with the inclusion of various local and international literature and studies, as well as the legal aspect devoted to the respective civil codes of the states cited in the paper.Due to such socio-economic developments, state ownership and its ownership function have changed. The state function as owner of property also changed in Macedonia's property law.The new constitutional sequence of the Republic of Macedonia since 1991 became privately owned as a dominant form of ownership, however, state ownership also exists.This process of transforming social property into state or private (dissolves), in Macedonia starts from Yugoslavia through privatization, return and denationalization measures, on which basis laws on privatization have been adopted. Because of this, there will be particularly intensive negotiations regaring the remaining state assets.

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Non Linear State and Parameters Estimation in Chemical Processes: Analysis and Improvement of Three Estimation Structures Applied to a CSTR

International Journal of Chemical Reactor Engineering ◽

10.1515/1542-6580.2439 ◽

2011 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Héctor Botero ◽

Hernán Álvarez

Keyword(s):

Parameter Estimation ◽

Chemical Process ◽

Chemical Processes ◽

The State ◽

Convergence Speed ◽

Parameters Estimation ◽

State Variables ◽

Input Output ◽

On Line ◽

Linear State

This paper proposes a new composite observer capable of estimating the states and unknown (or changing) parameters of a chemical process, using some input-output measurements, the phenomenological based model and other available knowledge about the process. The proposed composite observer contains a classic observer (CO) to estimate the state variables, an observer-based estimator (OBE) to obtain the actual values of the unknown or changing parameters needed to tune the CO, and an asymptotic observer (AO) to estimate the states needed as input to the OBE. The proposed structure was applied to a CSTR model with three state variables. With the proposed structure, the concentration of reactants and other CSTR parameters can be estimated on-line if the reactor and jacket temperatures are known. The procedure for the design of the proposed structure is simple and guarantees observer convergence. In addition, the convergence speed of state and parameter estimation can be adjusted independently.

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Exact bounded-error continuous-time linear state estimator

Systems & Control Letters ◽

10.1016/j.sysconle.2021.104951 ◽

2021 ◽

Vol 153 ◽

pp. 104951

Author(s):

Simon Rohou ◽

Luc Jaulin

Keyword(s):

Continuous Time ◽

State Estimator ◽

Bounded Error ◽

Linear State ◽

Time Linear

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Time-Dependent Reliability Analysis of Reinforced Concrete Beams Subjected to Uniform and Pitting Corrosion and Brittle Fracture

Materials ◽

10.3390/ma14081820 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1820

Author(s):

Mohamed El Amine Ben Seghier ◽

Behrooz Keshtegar ◽

Hussam Mahmoud

Keyword(s):

Reinforced Concrete ◽

Brittle Fracture ◽

Reliability Analysis ◽

Pitting Corrosion ◽

Structural Reliability ◽

Time Dependent ◽

State Function ◽

Rc Beams ◽

Highly Nonlinear ◽

Reliability Method

Reinforced concrete (RC) beams are basic elements used in the construction of various structures and infrastructural systems. When exposed to harsh environmental conditions, the integrity of RC beams could be compromised as a result of various deterioration mechanisms. One of the most common deterioration mechanisms is the formation of different types of corrosion in the steel reinforcements of the beams, which could impact the overall reliability of the beam. Existing classical reliability analysis methods have shown unstable results when used for the assessment of highly nonlinear problems, such as corroded RC beams. To that end, the main purpose of this paper is to explore the use of a structural reliability method for the multi-state assessment of corroded RC beams. To do so, an improved reliability method, namely the three-term conjugate map (TCM) based on the first order reliability method (FORM), is used. The application of the TCM method to identify the multi-state failure of RC beams is validated against various well-known structural reliability-based FORM formulations. The limit state function (LSF) for corroded RC beams is formulated in accordance with two corrosion types, namely uniform and pitting corrosion, and with consideration of brittle fracture due to the pit-to-crack transition probability. The time-dependent reliability analyses conducted in this study are also used to assess the influence of various parameters on the resulting failure probability of the corroded beams. The results show that the nominal bar diameter, corrosion initiation rate, and the external loads have an important influence on the safety of these structures. In addition, the proposed method is shown to outperform other reliability-based FORM formulations in predicting the level of reliability in RC beams.

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Reliability and reliability-based sensitivity analysis of self-centering buckling restrained braces using meta-models

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x211026382 ◽

2021 ◽

pp. 1045389X2110263

Author(s):

Seyede Vahide Hashemi ◽

Mahmoud Miri ◽

Mohsen Rashki ◽

Sadegh Etedali

Keyword(s):

Failure Probability ◽

Limit State ◽

Computational Cost ◽

Sensitivity Analyses ◽

State Function ◽

Reliability Indices ◽

Buckling Restrained Brace ◽

Polynomial Response Surface ◽

Nonlinear Dynamic Analyses ◽

High Computational Cost

This paper aims to carry out sensitivity analyses to study how the effect of each design variable on the performance of self-centering buckling restrained brace (SC-BRB) and the corresponding buckling restrained brace (BRB) without shape memory alloy (SMA) rods. Furthermore, the reliability analyses of BRB and SC-BRB are performed in this study. Considering the high computational cost of the simulation methods, three Meta-models including the Kriging, radial basis function (RBF), and polynomial response surface (PRSM) are utilized to construct the surrogate models. For this aim, the nonlinear dynamic analyses are conducted on both BRB and SC-BRB by using OpenSees software. The results showed that the SMA area, SMA length ratio, and BRB core area have the most effect on the failure probability of SC-BRB. It is concluded that Kriging-based Monte Carlo Simulation (MCS) gives the best performance to estimate the limit state function (LSF) of BRB and SC-BRB in the reliability analysis procedures. Considering the effects of changing the maximum cyclic loading on the failure probability computation and comparison of the failure probability for different LSFs, it is also found that the reliability indices of SC-BRB were always higher than the corresponding reliability indices determined for BRB which confirms the performance superiority of SC-BRB than BRB.

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