Garhy-Generated Family of Distributions with Application

This paper introduces a new family of continuous distributions called a Garhy generated family of distributions. Some mathematical properties of this family are discussed. The derived properties are hold to any proper distribution in this family. Some special sub-models in the new family are derived. General explicit expressions for the quantile function, ordinary and incomplete moments, generating function and order statistics are obtained. The estimation of the model parameters is discussed by using maximum likelihood and the potentiality of the extended family is illustrated with one application to real data. Keywords: Kumaraswamy distribution; Exponetiated distribution; Moments; quantile function, Maximum likelihood estimation

On the Extension of Exponentiated Pareto Distribution

In this study, an extended exponentiated Pareto distribution is proposed. Some statistical properties are derived. We consider maximum likelihood, least squares, weighted least squares and Bayesian estimators. A simulation study is implemented for investigating the accuracy of different estimators. An application of the proposed distribution to a real data is presented

Calibrating PIRLS Test in Sultanate of Oman Using Item Response Theory

The study aimed to calibrate Oman data of the PIRLS test using the graded response model and to examine the psychometric properties of it, as well as identify the fit and unfit of its items. PIRLS2011 test booklets were used, which consisted of 146 test items (74 dichotomous and 72 polytomous). Items were divided into 13 booklets; each with two blocks (one literary and one informational). PIRLS test booklets were administered to 13 groups of fourth grade students in Sultanate of Oman with a total sample of 10394 students. Assumptions of IRT (unidimensionality and local independence) were examined and supported. Also, item fit was examined and supported using Samejima’s graded response model. The data was analyzed by Multilog7.03 program to estimate both item and ability parameters. Results indicated that the assumptions of IRT were proved. Also, IRT analysis revealed that 8 items showed unfit which represents only 5% of the test items. So, this result confirms that the test has good psychometric properties under the IRT

On Type II Half Logistic Weibull Distribution with Applications

In recent years, several of new improved and extended probability distributions have been discovered from the current distributions to facilitate their applications in many fields. A new three-parameter distribution, the so called the Type II half logistic Weibull (TIIHLW), is introduced for modeling lifetime data. Some mathematical properties of the TIIHLW distribution are provided. Explicit expressions for the moments, probability weighted moments, quantile function, order statistics and Rényi entropy are investigated. Maximum likelihood estimation technique is employed to estimate the model parameters and simulation issues are presented. In addition, the superiority of the subject distribution is illustrated with an application to two real data sets.  Indeed, the TIIHLW model yields a better fit to these data than the beta Weibull, Mcdonald Weibull and exponentiated Weibull distributions. Keywords: Type II half logistic-G class; Weibull distribution, Order statistics; Maximum likelihood method. DOI: 10.7176/MTM/9-1-0

Reliability analysis of the new exponential inverted topp–leone distribution with applications

The inverted Topp–Leone distribution is a new, appealing model for reliability analysis. In this paper, a new distribution, named new exponential inverted Topp–Leone (NEITL) is presented, which adds an extra shape parameter to the inverted Topp–Leone distribution. The graphical representations of its density, survival, and hazard rate functions are provided. The following properties are explored: quantile function, mixture representation, entropies, moments, and stress– strength reliability. We plotted the skewness and kurtosis measures of the proposed model based on the quantiles. Three different estimation procedures are suggested to estimate the distribution parameters, reliability, and hazard rate functions, along with their confidence intervals. Additionally, stress–strength reliability estimators for the NEITL model were obtained. To illustrate the findings of the paper, two real datasets on engineering and medical fields have been analyzed

A study on the application of solar cells sensitized with a blackberry-based natural dye for power generation

This research paper is aimed at evaluating the use of natural dyes from blackberry (Rubus glaucus) obtained naturally for their subsequent application in laboratory solar cells to place them in dye-sensitized solar cells (DSSC) for the generation of electrical energy. The problem of the study is the high demand generated by global warming. Natural dyes were used to sensitize six solar cells, which were tested for their ability to absorb ultraviolet and visible light using a spectrophotometer in the ultraviolet-visible range, a solar simulator, and a current-voltage tester. The voltmeter was used to show how much energy each solar cell emitted over eight to 18 hours of daylight, with a required absorbance of 400-500 nm using six solar cells that had been sensitized with natural dyes. To reduce the high demand generated by global warming, use natural dyes from plant species as a supplement to improve efficiency in capturing renewable energy (solar) and converting it into electrical energy. Blackberries are lyophilized and then macerated for one day at room temperature in a dark, cool place to maximize dye's absorption. With two electrodes, the photo and contra, and an electrolyte in between, a Gratzel-type DSSC can be built. Using the doctor blade technique, the titanium dioxide film is added to the fluorine-doped tin oxide (TiO2) in the photoelectrode. By immersion, a natural colourant is then applied. TiO2 glass with a platinum film deposited on it serves as the counterelectrode

Synthesis of quinone-based heterocycles of broad-spectrum anticancer activity

A synthesis of benzo[e][1,2,4]triazines and 1,2,4-triazolospiro[4,5]deca-2,6,9-trien-8-ones has been developed from reactions of amidrazones with 2-chloro-1,4-benzoquinone in EtOAc containing 0.5 mL of piperidine. This highly regioselective and one-pot process provided rapid access to 1,2,4-triazolospiro[4,5]deca-2,6,9-trien-8-ones (60%-70%) and benzo[e][1,2,4]triazines (11%-18%). On reacting amidrazones with 5-hydroxy-1,4-naphthoquinone in an EtOAc/piperidine mixture, the reaction proceeded to give 5-hydroxy-2-(piperidin-1-yl)naphthalene-1,4-dione. The structures of the isolated products were proved by infrared, NMR (2D-NMR), mass spectra, and elemental analyses in addition to X-ray structure analysis. The reaction mechanisms are discussed. The anticancer screening of selected compounds showed broad-spectrum anticancer activity against most melanoma cancer cell lines, ovarian cancer OVCAR-3, central nervous system cancer SF-295 and U251, non-small cell lung cancer NCI-H23, renal cancer SN12C, and colon cancer HCT-15 and HCT-116. The selected compounds exhibited moderate to weak anticancer activity to other cell lines.Peer reviewe

Regioselective formation of 1,2,4-triazoles by the reaction of amidrazones in the presence of diethyl azodicarboxylate and catalyzed by triethylamine

A general method for the synthesis of 1,3,5-trisubstituted 1,2,4-triazoles has been developed from reaction of amidrazones with ethyl azodicarboxylate and triethylamine (Mitsunobu reagent) in EtOH. This highly regioselective one-pot process provides rapid access to highly diverse triazoles. The reaction was explained, based on Mitsunobu reagent oxidizing ethanol to acetaldehyde, which would then react with amidrazones to give the substituted 3-methyltriazoles. A [2 + 3] cycloaddition reaction between two oxidized forms of amidrazones produced the second type of triazoles. X-ray structure analyses proved the structure of each type of product. [GRAPHICS] .Peer reviewe