This article presents a new cascaded extended state observer (CESO)-based sliding-mode control (SMC) for an underactuated flexible joint robot (FJR). The control of the FJR has many challenges, including coupling, underactuation, nonlinearity, uncertainties and external disturbances, and the noise amplification especially in the high-order systems. The proposed control integrates the CESO and SMC, in which the CESO estimates the states and disturbances, and the SMC provides the system robustness to the uncertainty and disturbance estimation errors. First, a dynamic model of the FJR is derived and converted from an underactuated form to a canonical form via the Olfati transformation and a flatness approach, which reduces the complexity of th

A substantial portion of today’s multimedia data exists in the form of unstructured text. However, the unstructured nature of text poses a significant task in meeting users’ information requirements. Text classification (TC) has been extensively employed in text mining to facilitate multimedia data processing. However, accurately categorizing texts becomes challenging due to the increasing presence of non-informative features within the corpus. Several reviews on TC, encompassing various feature selection (FS) approaches to eliminate non-informative features, have been previously published. However, these reviews do not adequately cover the recently explored approaches to TC problem-solving utilizing FS, such as optimization techniques.

The study presents the modification of the Broyden-Flecher-Goldfarb-Shanno (BFGS) update (H-Version) based on the determinant property of inverse of Hessian matrix (second derivative of the objective function), via updating of the vector s ( the difference between the next solution and the current solution), such that the determinant of the next inverse of Hessian matrix is equal to the determinant of the current inverse of Hessian matrix at every iteration. Moreover, the sequence of inverse of Hessian matrix generated by the method would never  approach a near-singular matrix, such that the program would never break before the minimum value of the objective function is obtained. Moreover, the new modification of BFGS update (H-vers

It is well known that drilling fluid is a key parameter for optimizing drilling operations, cleaning the hole, and managing the rig hydraulics and margins of surge and swab pressures. Although the experimental works represent valid and reliable results, they are expensive and time consuming. In contrast, continuous and regular determination of the rheological fluid properties can perform its essential functions during good construction. The aim of this study is to develop empirical models to estimate the drilling mud rheological properties of water-based fluids with less need for lab measurements. This study provides two predictive techniques, multiple regression analysis and artificial neural networks, to determine the rheological

Nations are developed with education and knowledge that raise the status of society in its various segments, beyond that it leads to underdevelopment and deterioration in various sectors, whether economic, health, social, etc. If we considered the general name of The ministry of Education & Scientific Studies, then the second part seems to be not functioning, since scientific research has no material allocation and remains based on the material potential of the university professor. As for the first half of the topic, the reality of the situation reveals problems related to the Holy Trinity of Education which is (Professor - Student - the scientific method) where universities suffer at the present time from this problem, and

The aim of present study to investigate the effect of Coraindrum sativum leaves extract on reproductive activity of male albino mice .Thirty male mice with age of 80-100 day and weight between 25-30 g were divided into three groups: group 1 (untreated), group 2 and 3 were administrated orally for 30 days with aqueous extract of Coraindrum sativum leaves at dose 125 and 250mg/kg.b.w. respectively. The following parameters were evaluated: serum testosterone levels, testes weights, sperm characteristics [motility, viability, spermatozoa, morphology and concentration] and histology changes of the testis. The results showed that the treatment caused highly significant degrease (P<0.01) in testosterone levels and the weight of testes assoc

       Metaphor is a linguistic phenomenon related to people's cultures. It is an integral part of cultural heritage. This paper tackles the use of animal-based metaphors in the field of football club titles so as to draw comparisons between those in Russian with their counterparts in Arabic. Names of animals are used to refer to some clubs and teams, where these names or titles reflect animal features such as strength, preying on victims; or animal figures are employed in the club symbols, or due to the similarity of the club shirt to the animal outer shapes in colours. For instance, "an-Nawaris", which means gulls in English, is used to refer to az-Zawraa club du