In a hydroelectric power plant or in a pumping station in order to avoid sudden large increase of pressure due to instantaneous valve closure sometimes a surge tank is installed. The height of surge tank is designed by the highest possible water level during the operation. The theoretical treatment of oscillation in a surge tank is difficult because of the non-linearity of friction term in the ...

The application of surge-protective devices in lowvoltage systems faces the dilemma of providing effective limiting against surges while not attempting to limit the temporary overvoltages that do occur in a power system The paper illustrates this dilemma with specific scenarios and presents recommendations for reconciling these two conditions through adequate design and more explicit standards.

In his article "Possibilities and Limits of Comparative Literature Today" Darío Villanueva discusses the itinerary of comparative literature and its problematics and queries the discipline's adherence to literary history and its identification with the theory of literature. Villanueva's discussion is with particular reference to Spanish-language works such as by Claudio Guillén's systemic view ...

surge is one of the two destructive factors in compressors. surge is the stream instability phenomenon in compressor that imposes severe damages to the compressors. nowadays, suppressingsurge phenomenon is one of the most important issues in oil and gas industries, especially when flow reduction or gas reflux is considered. according to moore-greitzer compressor model, this paper designs an act...

High oral doses of atrazine (ATRA) disrupt normal neuroendocrine function, resulting in suppression of the luteinizing hormone (LH) surge in adult, ovariectomized (OVX) estrogen-primed female rats. While the mechanism by which ATRA inhibits LH secretion is not known, current data indicate that ATRA does have anti-estrogenic properties in vitro and in vivo. In the body, ATRA is rapidly converted...

In this paper we propose anti surge controllers for a close coupled valve in a compression system. The valve modifies the characteristic of the compressor, and allows for stable operation beyond the original surge line. The design tool used is backstepping and global uniform asymptotic stability is proven. Damping terms are included in the controllers, and in the presence of both mass flow and ...

As far as the design of SPDs is concerned, the need exists for simplifying its circuit structure in fulfilment of the prerequisite condition of protective reliability. The circuit simplification for SPDs is of benefit to lower the cost of manufacture and reduce the size of chassis. Considering that the traditional SPD that has been extensively used on single-phase AC power supply lines requires...

CaCiiuAing ~lt.0 ,~,o;-e s;irge-pi-o;efiiiie devices located r p y ~ c t i ~ ~ l y rrt the serl@ce e ! ! ~ m c e c>f CI building ar~d near the sensitive equipment is intended to ensure that each device shares the surge stress in an manner commensurate with its rating, to achieve reliable protection of equipment against surges impinging fi-om the utility supply as well as internally generated su...

Automotive manufacturers are showing an increasing preference for hybrid powertrains based on advanced gasoline engines. The most extended solution to improve fuel economy in these engines consists downsizing with direct injection, while turbocharging is required compensate the consequent power loss. However, associated different issues, such as compressor surge. It can appear during fast throt...