Adaptive sliding mode control for a class of MIMO nonlinear systems with uncertainties

This paper proposes an adaptive scheme of designing sliding mode control (SMC) for affine class of multi-input multi-output (MIMO) nonlinear systems with uncertainty in the systems dynamics and control distribution gain. The proposed adaptive SMC does not require any a priori knowledge of the uncertainty bounds and therefore offers significant advantages over the non-adaptive schemes of SMC design. The closed loop stability conditions are derived based on Lyapunov theory. The effectiveness of the proposed approach is demonstrated via simulations considering an example of a two-link robot manipulator and has been found to be satisfactory.     

Dielectrophoretic differentiation of mouse ovarian surface epithelial cells, macrophages, and fibroblasts using contactless dielectrophoresis

Ovarian cancer is the leading cause of death from gynecological malignancies in women. The primary challenge is the detection of the cancer at an early stage, since this drastically increases the survival rate. In this study we investigated the dielectrophoretic responses of progressive stages of mouse ovarian surface epithelial (MOSE) cells, as well as mouse fibroblast and macrophage cell lines, utilizing contactless dielectrophoresis (cDEP). cDEP is a relatively new cell manipulation technique that has addressed some of the challenges of conventional dielectrophoretic methods. To evaluate our microfluidic device performance, we computationally studied the effects of altering various geometrical parameters, such as the size and arrangement of insulating structures, on dielectrophoretic and drag forces. We found that the trapping voltage of MOSE cells increases as the cells progress from a non-tumorigenic, benign cell to a tumorigenic, malignant phenotype. Additionally, all MOSE cells display unique behavior compared to fibroblasts and macrophages, representing normal and inflammatory cells found in the peritoneal fluid. Based on these findings, we predict that cDEP can be utilized for isolation of ovarian cancer cells from peritoneal fluid as an early cancer detection tool.     

TS fuzzy robust L1 control for nonlinear systems with persistent bounded disturbances

In this paper, a novel technique for Takagi–Sugeno (TS) model-based robust L₁ controller design of nonlinear systems is proposed. Two synthesis methods based on quadratic and non-quadratic Lyapunov functions are considered. To design the robust stabilizing controller, a new approach for deriving sufficient conditions associated with the L₁ performance criterion in terms of strict linear matrix inequality is proposed. This novel technique results in less pre-chosen scalar design variables and calculation burden. Furthermore, deriving the controller synthesis conditions via a non-quadratic Lyapunov function (NQLF) relaxes the obtained conditions. Therefore, the proposed approaches not only efficiently minimize the effect of persistent bounded disturbance, but also are applicable for wider classes of TS systems. Furthermore, some new lemmas are proposed to facilitate strict LMI formulation and to provide more degrees of freedom. Finally, several numerical and practical examples are presented to show the merits of this paper.     

Bridging the gap between higher education and the Telecommunications Engineering Sector

In this paper, the growth of the telecommunication sector in Pakistan and consequent development in the related professional education is studied. The widening gap between the telecommunication industry and associated education sector is identified. The higher educational programs in Pakistan have grown very rapidly to meet the needs of the explosive growth in the telecommunications＇ engineering sector but this growth is not in synchronization with the requirements of the industry due to non-existence of collaboration and co-operation between the two. The professional education in telecommunication in Pakistan and the higher educational degree programs are very precisely focused on producing quality graduates with refined technical and mathematical skills While the telecom sector in Pakistan is in principle a service provider and a consumer market that mainly requires engineers for operation and maintenance related activities. As such the skills imparted by the education sector are rarely utilized, which results in dissatisfaction among the telecommunications＇ engineers. A survey of both the telecommunication sector and the academia has been conducted along with detailed discussions to explore the reasons for this ever-increasing gap, ways and means to arrest this trend and future course of action for the academia and the telecom sector to develop. A study related to other emerging technical fields like computer science has also been made for the comparison. On the basis of this extensive exercise outlined above, measures have been suggested to bridge the gap between the education and the industrial needs of the telecom sector. By adopting these measures not only our education sector will become more beneficial to the industry, but the industry would also get the advantage of immense potential of young graduates and the academic research.     

Organizational culture,values, and routines in Iranian medical schools

In Iran, restructuring of medical education and the health care delivery system in 1985 resulted in a rapid shift from elite to mass education, ultimately leading to an increase in the number of medical schools, faculties, and programs and as well as some complications. This study aimed to investigate views on academic culture, values, and routines held by faculty members. A nation-wide survey conducted in six public medical schools in Iran. The research findings show weak organizational culture and values, together with routine behaviors sensed as a negative and low satisfaction with academic leadership. The research evidence suggests bureaucracy, politicization, conservativeness, and centralization as common features of medical schools in Iran and also suggests suitable supervisory skills to tackle the tension between governmental management and academic leadership with cultural changes, the creation of new values, and adoption more efficient routines.