This article focuses on parameter estimation in a simple linear regression model, assuming that the error terms follow the one of the skewed distributions is Gumbel and dataset contains outliers. The unknown model parameters are estimated using the traditional least squares (LS) method as well as robust estimation methodologies, including the least absolute deviation (LAD), weighted least absolute deviation (WLAD), and least squares median (LMS). The performance of these estimators is evaluated against the LS estimator using BIAS and mean square error (MSE) measures as criteria. A Monte Carlo simulation study was conducted to assess their effectiveness on datasets with outliers in explanatory variable (leverage point). The simulation results reveal that the LMS estimator outperforms the other methods in all considered outlier scenarios, demonstrating greater efficiency and robustness regardless of the presence of outliers. Furthermore, the practical applicability of the proposed estimators is illustrated through an analysis of the data set, which was intentionally modified by introducing varying percentages of outliers. This real-world example underscores the effectiveness of the robust estimators, particularly the LMS, in handling data contaminated by anomalies.

The bit-carrying capacity of Switched Local Area Networks (Switched LANs) is an important parameter for managing the performance of this class of networks. But, there do not seem to be available, formal method or methods for determining this parameter. This paper reports the development of a formal method for determining the capacity of switched LANs. It also reports a formal method for determining the capacity to be subscribed for, when a Switched LAN is to be connected to the Internet through an Internet Service Provider (ISP). Illustrative examples applying both methods, is also reported.

In this paper, we aim to introduce a new category of expansive mappings called F-expansive mappings thereby generalizing the expansion mappings in a distinct way as compared to the known results from the literature. Our new notion complements the concept of F-contraction introduced recently by Wardowski (Fixed Point Theory and Applications 2012 \\textbf{2012}:94). Our results improve and extend the corresponding results announced by many others. We also provide an example to support the results presented therein.

This study explored the attitudes of teachers towards the use of interactive whiteboards (IWBs) in Mathematics teaching and learning contexts, and also sought insights into teachers\' actual use of IWBs in Mathematics classes. The study also investigated possible factors affecting teachers\' positive and negative attitudes towards IWB technology. Data were collected through questionnaires distributed to 82 teachers in different institutions across Andimeshk, Iran, from Secondary schools. Questionnaire results revealed that teachers have positive attitudes towards the use of IWBs in Math instruction and are aware of the potential of this technology. Responses given in interviews indicated that all Math teachers are supportive of IWB technology in their classes, and observations revealed that IWBs are used with their basic functions in Math classes. The statistical analysis revealed that the more teachers use IWBs, the more they like this technology

Due to the prolonged use of wind turbines they must be characterized by high reliability. This can be achieved through a rigorous design, appropriate simulation and testing and proper construction. The reliability prediction and analysis of these systems will lead to identifying the critical components, increase the operating time, minimizing failure rate and minimizing maintenance costs. The Monte-Carlo simulation of parameters of helical vertical axis wind turbine includes elements of reliability theory and notions of probability and statistical inferences. To estimate the produced energy by the wind turbine, an evaluation approach based on the Monte Carlo simulation model is developed which enables us to estimate the probability of minimum and maximum parameters. In our simulation process we used triangular distributions. The analysis of simulation results has been focused on the interpretation of the relative frequency histograms and cumulative distribution curve (ogive diagram), that indicates the probability of obtaining the daily or annual energy output depending on wind speed. \nThe case study consists on determination of statistical parameters of assumed distribution, in order to estimate the reliability and unreliability functions, probability density function (pdf) and hazard rate (failure rate) of the helical vertical axis wind turbine designed and patented to climatic conditions for Romanian regions. Based on experimental tests, the variation of power produced for different wind speed, the Weibull distribution of wind probability and the power generated was estimated. The analysis of experimental results indicates that this type of wind turbine at low wind speed is more efficient than other wind turbines with horizontal axis and with three blades.

In this paper we consider the GPQ-metric spaces which is a generalized Partial quasi-metrics and GQ-metric spaces which is a generalized quasi-metrics.

In this paper explain preparation of 2-Benzyl 5-Oxo 5-H 6 -R-amide derivatives 7-phenyl 1,3,4-thiadiazolo-[3,2-a]- pyrimidine through reaction of 2-Benzyl 5-Oxo 5-H 6- EthylCarboxilate 7- phenyl -1, 3,4 -thiadiazolo-[3,2-a]- pyrimidine with amin derivatives.The reactions are completed in Very short time with high yield. Interest in the synthesis of pyrimidine derivatives is due to their biological activities. The structures of all the newly synthesized compounds had been identified by elemental analysis, set NMR, 13C, IR- spectroscopy.

The Essaouira synclinal area is a part of the semi-arid areas of Morocco which are subject to the impacts of climate and anthropogenic pressures. It’s also expected to know an important agro-industrial development. Water requirements are important for the development of all these activities. Although the situation is not yet alarming, the fact remains that the quality of groundwater resources is constantly put to the test because of the growth sources as diffuse pollution that point. To prevent pollution of groundwater, one approach is the knowledge of especially vulnerable areas. It’s for this reason that this study was initiated to produce a map of intrinsic vulnerability of aquifers in the region. The method used to make the card is the numerical rating DRASTIC method (Aller et al. 1987). The integration and combination cards hydrogeological factors, GRID format in the GIS environment in ArcView 3.2 and Surfer 10, was used to calculate indices of vulnerability. These vulnerability indices obtained by this method were classified into four categories (low, medium, high and very high). The results indicate that the region is dominated by the class of high vulnerability (61%) followed by the class of very high vulnerability (20%), then the class of medium vulnerability (15%) and the class of low vulnerability (4 %). Class very high vulnerability is located in the western coastal area. The center of the basin is dominated by the class of high vulnerability, to the east, the past of medium and low class. Almost throughout the Oued Ksob is particularly dominated by the class of high vulnerability.