Jahangirnagar University Journal of Science

Bayesian Estimation of Fecundability for Heterogeneous Cohort of Women using Asymmetric Loss Functions

2023-01-17T18:38:25+06:00

In this paper, we present a Bayesian approach to find the estimators of fecundability parameter for heterogeneous cohort of women population using non-linear exponential (NLINEX) and linear-exponential (LINEX) loss functions, both are asymmetric. The asymmetry brings about the shift of location of the loss function. A study of the derived estimators are also done

An Efficient Method for Solving Traveling Salesman Problem

2023-01-17T19:00:19+06:00

The traveling salesman problem (TSP) consists of a salesman and a set of cities. The salesman has to visit each one of the cities starting from a certain one (e.g. the home city) and returning to the same city. The challenge of the problem is that the traveling salesman wants to minimize the total length of the trip. In this paper, we introduce and analyze a variation of the Traveling Salesman problem.
The paper will cover algorithms for TSP to take the decision which optimizes the distance. Our proposed algorithm helps to determine the optimum distance with less number of iteration by easiest way and presents alternative method for solving the classical traveling salesman problem (TSP). Several numerical examples are solved to test the performance of the proposed method. The comparison of the result shows that proposed algorithm is efficient for solving the TSPs.

Prevalence, Patterns, and Determinants of Contraceptive Practices among Married Women in Bangladesh

2023-01-17T19:20:26+06:00

To assess the prevalence, patterns and identify the determinants of contraceptive usage among married women in Bangladesh. This study considers a country representative 2014 BDHS dataset. The results reveal that 68.9 percent and 63.4 percent of married women aged between 15 and 49 years used different contraceptive methods in urban and rural areas respectively. In the case of rural areas, respondent’s education, age, religion, region, number of living children, respondent’s employment status, husband’s occupation, and
fertility preference are the most important indicators of using contraceptives. However, Age, religion, residency, number of living children, age at first sex, number of living children, husband's desire for children, and hearing about family planning on adio/TV/magazine are all major factors in urban settings. There is less tendency of using contraceptive methods in rural areas than in urban areas. The government and non-government organizations who are concerned about family planning in Bangladesh should be taken an action in rural areas in order to increase the rate of contraceptive use.

Classical and Robust Correlation Estimates: A Comparative Study

2023-01-17T18:47:36+06:00

For conducting correlational analysis, one may be faced with statistical problem if the dataset contains outliers and other contaminations. In order to use any correlation method when the dataset contains outliers, one must know the stability of that correlation method. For this reason, it is essential to check the stability of the considered classical correlations and robust correlations so that we can use those correlations without any doubt in our mind. In this paper, several contamination cases have been introduced for checking the stability of the classical and robust correlations that are considered. The performances of robust correlations and classical correlations are compared and also performances of robust correlations among each other are compared through a simulation study and real data examples both for study clean data and contaminated data. Based on simulation study and real data applications, robust correlations have much better performance compared to classical correlations from clean to contaminated data. Among the robust correlations adjusted bivariate winsorized correlation has more stability than any other robust correlations. When some observations in real dataset are replaced by outliers, classical correlation i.e. Pearson correlation is changed drastically and robust
correlations remain almost same.

Comparison of the Methods for Numerical Integration

2023-01-17T19:28:03+06:00

Numerical integration methods are generally helpful to determine the integral value of a function for which the integration becomes difficult or when it is impossible to find out the exact integral value. The main objective of this paper is to determine the optimum number of partitions for various numerical integration methods so that these methods can give us the best approximate result. We have used these methods to get the optimum result in such a way that after setting initial partitions, these methods will automatically continue to take more additional partitions until the difference between two successive integral values will be less than the considered tolerance limit. For each of the methods, we have recorded the number of steps to get the optimum number of partitions along with their computational error and average CPU time. Among all the considered methods, Weddle’s rule outperformed compared to other methods because it has required less optimum number of steps and less average CPU time, and also produced a small amount of computational error to obtain the approximate integral value. The composite integration method also performed well for a large number of subdivisions. But one limitation of the method is that what number of subdivisions should be taken for a good result is not fixed in advance. After that, the order of the methods which performed well is Boole's rule, Simpson’s 3/8 rule, Simpson’s rule, Simpson’s 1/3 rule, Midpoint rule and Trapezoidal rule respectively.

A green technique for non-catalytic solubilization and hydrolysis of crystalline cellulose

2023-01-17T19:36:47+06:00

A unique method was established for the decomposition of cellulose using a strong gravitational field at room temperature to recover useful chemical intermediates. Experiments of decomposition of microcrystalline cellulose were conducted at room temperature for 24 hours to a gravitational field of 0.33 x 106 G generated by an ultracentrifuge rotating at 80,000 rpm using a speciallydesigned gravity apparatus. After gravity experiment, we analyzed the compounds by LC-MS spectra and HPLC respectively and showed that stronggravity treatment of microcrystalline cellulose was successfully hydrolyzed to form cello-oligosaccharides and glucose, and surprisingly phenolic compounds such as guaiacol derivatives.