over a period of three months (summer), 108 samples of water collected from four hospitals in te-hran. they were taken from numerous potable and non-potable water, including main supply cis-terns, calorifiers, hot and cold tap water, shower, cooling tower and drain of air condition system. culturing of concentrated and non-concentrated water samples on buffered charcoal yeast extract (bcye) aga...

Foundation of tower crane serves to ensure stability against vertical and horizontal forces. If foundation stress is not sufficient, tower crane may be subject to overturning, shearing or foundation settlement. Therefore, engineering review of stable support is a highly critical part of foundation design. However, there are not many professionals who can conduct engineering review of tower cran...

With appropriate vibration modeling and analysis the incipient failure of key components such as the tower, drive train and rotor of a large wind turbine can be detected. In this paper, the Nonlinear State Estimation Technique (NSET) has been applied to model turbine tower vibration to good effect, providing an understanding of the tower vibration dynamic characteristics and the main factors in...

A heuristic method for optimizing a solar power tower system is proposed, in which both heliostat field (heliostat locations and number) and the tower (tower height and receiver size) are simultaneously considered. Maximizing the thermal energy collected per unit cost leads to a difficult optimization problem due to its characteristics: it has a nonconvex black-box objective function with compu...

In the design of DC system, more than one MVU tower may be used between pole-to-neutral voltages. This is especially common for UHVDC systems. The insulation design of these MVU’s need to be verified by dielectric type tests as specified by international standards. However, the application of several MVU’s in series makes the test set-up complicated. One straightforward solution is to install a...

An updraft tower cooling system is assessed for elimination of water use associated with power plant heat rejection. Heat rejected from the power plant condenser is used to warm the air at the base of an updraft tower; buoyancy-driven air flows through a recuperative turbine inside the tower. The secondary loop, which couples the power plant condenser to a heat exchanger at the tower base, can ...

This paper presents a universal engineering model, which can be used to formulate both counterflow and crossflow cooling towers. By using fundamental laws of mass and energy balance, the effectiveness of heat exchange is approximated by a second order polynomial equation. Gauss-Newton and Levenberg-Marquardt methods are then used to determine the coefficients from manufactures data. Compared wi...