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Article

Amel Bouakkadia, Leila Lourici and Djelloul Messadi

The purpose of this paper is to predict the octanol/water partition coefficient (Kow) of 43 organophosphorous compounds.

Abstract

Purpose

The purpose of this paper is to predict the octanol/water partition coefficient (Kow) of 43 organophosphorous compounds.

Design/methodology/approach

A quantitative structure-property relationship analysis was performed on a series of 43 pesticides using multiple linear regression and support vector machines methods, which correlate the octanol-water partition coefficient (Kow) values of these chemicals to their structural descriptors. At first, the data set was randomly separated into a training set (34 chemicals) and a test set (nine chemicals) for statistical external validation.

Findings

Models with three descriptors were developed using theoretical descriptors as independent variables derived from Dragon software while applying genetic algorithm-variable subset selection procedure.

Originality/value

The robustness and the predictive performance of the proposed linear model were verified using both internal and external statistical validation. One influential point which reinforces the model and an outlier were highlighted.

Details

Management of Environmental Quality: An International Journal, vol. 28 no. 4
Type: Research Article
ISSN: 1477-7835

Keywords

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Article

Hamid Reza Ghaieni, Saeed Tavangar and Mohammad Moein Ebrahimzadeh Qhomi

The purpose of this paper is to present simple correlation for calculating nitrated hydroxyl-terminated polybutadiene (NHTPB) enthalpy of formation.

Abstract

Purpose

The purpose of this paper is to present simple correlation for calculating nitrated hydroxyl-terminated polybutadiene (NHTPB) enthalpy of formation.

Design/methodology/approach

It uses multiple linear regression methods.

Findings

The proposed correlation has determination coefficient 0.96. The correlation has root mean square deviation and the average absolute deviations values 53.4 and 46.1 respectively.

Originality/value

The predictive power of correlation is checked by cross-validation method (R2=0.96, Q L O O 2 = 0.96 ).

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

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Article

Nadia Ziani, Khadidja Amirat and Djelloul Messadi

– The purpose of this paper is to predict the aquatic toxicity (LC50) of 92 substituted benzenes derivatives in Pimephales promelas.

Abstract

Purpose

The purpose of this paper is to predict the aquatic toxicity (LC50) of 92 substituted benzenes derivatives in Pimephales promelas.

Design/methodology/approach

Quantitative structure-activity relationship analysis was performed on a series of 92 substituted benzenes derivatives using multiple linear regression (MLR), artificial neural network (ANN) and support vector machines (SVM) methods, which correlate aquatic toxicity (LC50) values of these chemicals to their structural descriptors. At first, the entire data set was split according to Kennard and Stone algorithm into a training set (74 chemicals) and a test set (18 chemical) for statistical external validation.

Findings

Models with six descriptors were developed using as independent variables theoretical descriptors derived from Dragon software when applying genetic algorithm – variable subset selection procedure.

Originality/value

The values of Q2 and RMSE in internal validation for MLR, SVM, and ANN model were: (0.8829; 0.225), (0.8882; 0.222); (0.8980; 0.214), respectively and also for external validation were: (0.9538; 0.141); (0.947; 0.146); (0.9564; 0.146). The statistical parameters obtained for the three approaches are very similar, which confirm that our six parameters model is stable, robust and significant.

Details

Management of Environmental Quality: An International Journal, vol. 27 no. 3
Type: Research Article
ISSN: 1477-7835

Keywords

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Article

Bing Hua, Nan Zhang and Mohong Zheng

Taking into account the factors of torque saturation and angular velocity limitation during the actual attitude maneuver of the satellite, as well as the difficulty of…

Abstract

Purpose

Taking into account the factors of torque saturation and angular velocity limitation during the actual attitude maneuver of the satellite, as well as the difficulty of parameter selection in the design of attitude control algorithm, the purpose of this paper is to propose a satellite magnetic/momentum wheel attitude control technology based on pigeon-inspired optimization (PIO) cascade-saturation control law optimization.

Design/methodology/approach

The optimal parameters are calculated through the PIO algorithm and then the parameters are used in the cascade-saturation control law to control the actuator findings-mathematical simulation results show that the cascade-saturation control law optimization algorithm based on PIO can shorten the adjustment time and reduce the steady-state error.

Findings

Compared with traditional attitude maneuver control with given parameters, the PIO algorithm can accurately calculate the optimal parameters needed to achieve the control objective and this method has better stability and higher accuracy.

Originality/value

The innovative PIO algorithm is used to calculate the optimal parameters, and the cascade saturation control law is used to control the actuator. Compared with the traditional algorithm, the regulation time is shortened and the steady-state error is reduced.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

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Abstract

Purpose

The purpose of this paper is to predict the retention times of 84 pesticides or toxicants.

Design/methodology/approach

Quantitative structure – retention relationship analysis was performed on a set of 84 pesticides or toxicants using a hybrid approach genetic algorithm/multiple linear regression (GA/MLR).

Findings

A model with six descriptors was developed using as independent variables. Theoretical descriptors derived from Spartan and Dragon softwares when applying GA/MLR approach.

Originality/value

A six parameter linear model developed by GA/MLR, with R² of 90.54, Q² of 88.15 and S of 0.0381 in Log value. Several validation techniques, including leave-many-out cross-validation, randomization test, and validation through the test set, illustrated the reliability of the proposed model. All of the descriptors involved can be directly calculated from the molecular structure of the compounds, thus the proposed model is predictive and could be used to estimate the retention times of pesticides or toxicants.

Details

Management of Environmental Quality: An International Journal, vol. 27 no. 3
Type: Research Article
ISSN: 1477-7835

Keywords

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Article

Shankar Reddy Kolle, M.S. Vijayashree and T.H. Shankarappa

The purpose of this paper is to reveal the bibliometric characteristics of highly cited articles in Malaria research for the period of 1991-2015.

Abstract

Purpose

The purpose of this paper is to reveal the bibliometric characteristics of highly cited articles in Malaria research for the period of 1991-2015.

Design/methodology/approach

The data of highly cited articles for the period of 1991 to 2015 were extracted from the Science Citation Index Expended of Web of Science. The keyword “Malaria” was used as topic term to search documents that contained this word in the title or keyword or abstract of the documents that published in 1991 to 2015. A total of 1,614 articles having TC2015 = 100 were retrieved as highly cited articles for further analysis, and Microsoft excel was used for the analysis purpose.

Findings

A total of 1,614 of highly cited articles were published in the 230 journals for the period of 1991 to 2015, and majority of the articles were appeared in journals that have top impact factor. The articles published in the 2011s have greater average citations and authors per article. Six journals have produced almost a quarter of highly cited articles and remaining articles were published in 224 journals. Proceedings of the National Academy of Sciences of the USA was the most productive journal with 154 articles, which accounts for 9.53 per cent of the total articles, followed by Lancet (110; 6.81 per cent). We found degree collaboration value of 0.971 for the articles, which indicates the clear dominance of multiple authors in publication of highly cited articles in Malaria research. In this study, new indictor called P index was applied for the evaluation of the author’s productivity. As per the p-value, the White, NJ has emerged as the most productive author with the p-value of 0.41 (61 articles), followed by Marsh, K (p = 0.33), Nosten, F (p = 0.32) and Snow, RW (p = 0.31). The USA and the UK were the most productive countries. The article entitled as “Global and regional burden of disease and risk factors, 2001: systematic analysis of population health data” contributed by Lopez et al. (2006) was the most cited article with 2,245 citations in 2015.

Research limitations/implications

The data for the present study was limited to the publications that indexed in Science Citation index Expended of Web of Science.

Originality/value

This paper would be useful to the researchers to know the trends and achievements in the Malaria research and also to the library and information science professionals in collection building process.

Details

Collection Building, vol. 36 no. 2
Type: Research Article
ISSN: 0160-4953

Keywords

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