Hashem Saberi and SA Edalatpanah
The Weighted Linear Least Squares (WLLS) problem has many different applications in sciences and engineering. The purpose of this paper is to introduce an iterative scheme for…
Abstract
Purpose
The Weighted Linear Least Squares (WLLS) problem has many different applications in sciences and engineering. The purpose of this paper is to introduce an iterative scheme for solving the WLLS problem.
Design/methodology/approach
By considering the splitting techniques in conjunction with Generalized Accelerated Over-relaxation (GAOR) method the authors design a new iterative method to solve the weighted linear least squares problem. Furthermore, within the computational framework, some models of iterative schemes candidates are investigated and evaluated.
Findings
In this paper, the authors propose an efficient iterative scheme for solving the WLLS problem. The proposed scheme presented promising results from the aspects of both convergence behavior and performance. Moreover, comparative results for the proposed schemes are also presented.
Research limitations/implications
Comparison between the new methods and other similar methods for the studied problem shows a remarkable agreement and reveals that the new model is much better in comparison with the existing methods in point of view rate of convergence and computing efficiency, as illustrated by the theoretical analysis and numerical results presented.
Originality/value
For solving WLLS more attention has recently been paid on a special class of splitting techniques with the preconditioned GAOR method. In this paper, the authors use a different splitting for the GAOR method and present a promising class of methods. The convergence results of the iterative algorithm are also proposed. Several examples are given to show the efficiency of the presented methods.
H. Saberi Najafi and S.A. Edalatpanah
– The purpose of this paper is to present the efficient iterative methods for solving linear complementarity problems (LCP), using a class of pre-conditioners.
Abstract
Purpose
The purpose of this paper is to present the efficient iterative methods for solving linear complementarity problems (LCP), using a class of pre-conditioners.
Design/methodology/approach
By using the concept of solving the fixed-point system of equations associated to the LCP, pre-conditioning techniques and Krylov subspace methods the authors design some projected methods to solve LCP. Furthermore, within the computational framework, some models of pre-conditioners candidates are investigated and evaluated.
Findings
The proposed algorithms have a simple and graceful structure and can be applied to other complementarity problems. Asymptotic convergence of the sequence generated by the method to the unique solution of LCP is proved, along with a result regarding the convergence rate of the pre-conditioned methods. Finally, a computational comparison of the standard methods against pre-conditioned methods based on Example 1 is presented which illustrate the merits of simplicity, power and effectiveness of the proposed algorithms.
Research limitations/implications
Comparison between the authors' methods and other similar methods for the studied problem shows a remarkable agreement and reveals that their models are superior in point of view rate of convergence and computing efficiency.
Originality/value
For solving LCP more attention has recently been paid on a class of iterative methods called the matrix-splitting such as AOR, MAOR, GAOR, SSOR, etc. But up to now, no paper has discussed the effect of pre-conditioning technique for matrix-splitting methods in LCP. So, this paper is planning to fill in this gap and the authors use a class of pre-conditioners with iterative methods and analyze the convergence of these methods for LCP.
Details
Keywords
Jianzhong Li, Alhanouf Alburaikan and Rita de Fátima Muniz
The main purpose of this paper is to create a suitable structure based on neutrosophic numbers to evaluate the safety performance in construction projects in such a way that the…
Abstract
Purpose
The main purpose of this paper is to create a suitable structure based on neutrosophic numbers to evaluate the safety performance in construction projects in such a way that the shortcomings can be highlighted with the reasoned measurement and possible strategies can be recommended.
Design/methodology/approach
Data envelopment analysis (DEA), which is a useful tool for performance appraisal, along with neutrosophic logic, which is one of the most complete tools for handling uncertainty phenomenon, has been used to evaluate the safety performance of construction projects. With this hybrid model, a new strategy is considered as an indicator for safety performance and comparisons are made between different units.
Findings
A total of 35 Chinese organizations with construction projects lasting between 1.5 and 2 years were selected for comparison. After processing the data into neutrosophic numbers and using the NN-DEA model, it can be found that projects that pay more attention to safety issues such as training and equipment are more efficient.
Originality/value
Since in the real world, there are uncertainties with different contradictions, and neutrosophical data can handle many of these challenges, using DEA model with neutrosophic numbers to evaluate the performance of construction projects from a safety perspective, can provide significantly better results. Therefore, considering that no study has been presented in this field so far, the authors will deal with this topic.
Details
Keywords
Ibrahim M. Hezam, Anand Kumar Mishra, Dragan Pamucar, Pratibha Rani and Arunodaya Raj Mishra
This paper develops a decision-analysis model to prioritize and select the site to establish a new hospital over different indicators such as cost, market conditions…
Abstract
Purpose
This paper develops a decision-analysis model to prioritize and select the site to establish a new hospital over different indicators such as cost, market conditions, environmental factors, government factors, locations and demographics. In this way, an integrated model is proposed under the intuitionistic fuzzy information (IFI), the standard deviation (SD), the rank-sum (RS) and the measurement of alternatives and ranking using the compromise solution (MARCOS) approach for ranking hospital sites (HSs).
Design/methodology/approach
The IF-SD-RS model is presented to obtain the combined weight with the objective and subjective weights of diverse sub-criteria and indicators for ranking sites to establish the hospital. The IF-MARCOS model is discussed to prioritize the various sites to establish the hospital over several crucial indicators and sub-criteria.
Findings
The authors implement the developed model on a case study of HSs assessment for the construction of new hospital. In this regard, inclusive set of 6 key indicators and 18 sub-criteria are considered for the evaluation of HSs. This study distinguished that HS (h2) with combined utility function 0.737 achieves highest rank compared to the other three sites for the given information. Sensitivity analysis is discussed with different parameter values of sub-criteria to examine how changes in weight parameter ratings of the sub-criteria affect the prioritization of the options. Finally, comparative discussion is made with the diverse extant models to show the reasonability of the developed method.
Originality/value
This study aims to develop an original hybrid weighting tool called the IF-SD-RS model with the integration of IF-SD and IF-RS approaches to find the indicators' weights for prioritizing HSs. The developed integrated weighting model provides objective weight by IF-SD and subjective weight with the IF-RS model. The model presented in the paper deals with a consistent multi-attribute decision analysis (MADA) concerning the relations between indicators and sub-criteria for choosing the appropriate options using the developed IF-SD-RS-MARCOS model.