A historical review of absenteeism in the popular press is presented through a sample of articles appearing in the New York Times from 1904 to 2004. The review demonstrates the negative perception of absenteeism over the years while also exposing diversity in the treatment of absence in terms of perceived causes, effects, and strategies to combat it. The findings offer insight into social expec...

Multilevel converters offer high power capability, associated with lower output harmonics and lower commutation losses. Their main disadvantage is their complexity, requiring a great number of power devices and passive components, and a rather complex control circuitry. This paper proposes a single-phase sevenlevel inverter for grid connected PV systems, with a novel pulse width-modulated (PWM)...

this paper presents a new centralized adaptive method under frequency load shedding. sometimes, after initial frequency drop following severe disturbances, although the system frequency returns to its permissible value, however, the system might become unstable due to voltage problems. in this regard, the paper proposes a new centralized adaptive load shedding method to enhance the voltage stab...

In this paper, a distributed method for reactive power management in a distribution system has been presented. The proposed method focuses on the voltage rise where the distribution systems are equipped with a considerable number of photovoltaic units. This paper proposes the alternating direction method of multipliers (ADMMs) approach for solving the optimal voltage control problem in a distri...

Weifeng Su and Xiang-Gen Xia. 2003. "On Space-Time Block Codes from Complex Orthogonal Designs", Wireless Personal Communications 25: 1–26. A. V. Geramita and J. Seberry. 1979. Orthogonal Designs, Quadratic Forms and Hadamard Matrices. Lecture Notes in Pure and Applied Mathematics, Vol. 43, Marcel Dekker: New York and Basel. V. Tarokh, H. Jafarkhani and A. R. Calderbank. 1999. "S...

Power grids with high integration of power electronic converters face new issues that have not existed before. The frequency in the system is highly related to inertia and rotational speed operational synchronous machines. This now changing, as converter-based generation units are contributing increasingly balancing active modern grid. Several control designs for electronic-based been presented...

This paper investigates the robust decentralized nonlinear control of power flow in a power system using a new configuration of UPFC. This structure comprises two shunt converters and one series capacitor called as hybrid power flow controller (HPFC). A controller is designed via control Lyapunov function (CLF) and adaptive observer to surmount the problems of stability such as tracking desired...

40. D. Morais, J. Rolim, and Z. Vale, DITRANS – A multi-agent system for integrated diagnosis of power transformers, Proc. of POWERTECH 2007, Lausanne, Switzerland, 2007. 41. R. Giovanini, K. Hopkinson, D. Coury, and J. Thorp, A primary and backup cooperative protection system based on wide area agents, IEEE Trans. Power Delivery, 21 (3): 1222– 1230, 2006. 42. J. Solanki, S. Khushalani, and N. ...