The effect of evanescent mode generation, due to geometrical mismatch, in acoustic impedance measurements is investigated. The particular geometry considered is that of a impedance probe with an annular flow port and a central microphone, but the techniques are applicable to other geometries. It is found that the imaginary part of the measured impedance error is proportional to frequency, and t...

Storm surge is dependent on wind direction, with maximum surge heights occurring when strong winds blow onshore. It is less obvious what happens when a port city is situated at the end of a long narrow gulf, like Venice at the northwestern end of the Adriatic Sea. Does the narrow marine approach to the port city limit the dangerous wind direction to a span of only a few degrees? This modeling s...

The separation of bubbles in a gas–liquid cyclone is complicated. A combination numerical simulation and visual experimentation was considered apt to reveal the microscopic mechanisms bubble flow. First all, cyclones with different structures were numerically simulated. calculation results show that larger diameter exhaust port, better flow effect. When port 24 mm, gas discharge efficiency 8% h...

A previously developed reciprocating air microcompressor having a 1-mm(0.04 in)-diameter piston, an inlet port that did not have a moving valve, and an outlet port equipped with a miniature reed valve, was capable of a maximum discharge pressure of 80 kPa (gage, 11.6 psig) at a piston frequency of 100 Hz. We have improved on this compressor performance, and have attained a maximum discharge pre...

considerable amounts of different pollutants, especially crude oils, are present in the persian gulf and its northern region, so biomonitoring the effect of these pollutants on its biota is necessary. ethoxyresorufin o-deethylase (erod), gluthathione s-transferase (gst) and catalase (cat) activity were measured from biochemical level in the gills of mudskipper periophthalmus waltoni collected f...

The basic design of what was to become the Triservice Apparatus (TSA) was first described in 1968 [1]. It consisted of two Oxford Miniature Vaporisers (OMV) placed in series, leading to an Oxford Inflating Bellows, a length of corrugated tubing, expiratory valve and face mask. Air was used as a carrier gas, but it was noted that a T piece could be attached to the inlet port of one of the vapori...

The forced oscillation technique is useful in detecting changes in upper airway obstruction in patients with sleep apnoea undergoing continuous positive airway pressure (CPAP) ventilation. The aim of this study was to implement and evaluate a method for estimating respiratory impedance (Zrs) from the pressure and flow recorded at the inlet of the CPAP tubing. The method is based on correcting i...

Introduction The Sinclair and Dyes Inlet watershed is located on the west side of Puget Sound in Kitsap County, Washington, U.S.A. (Figure 1). The Puget Sound Naval Shipyard (PSNS), U.S Environmental Protection Agency (USEPA), the Washington State Department of Ecology (WA-DOE), Kitsap County, City of Bremerton, City of Bainbridge Island, City of Port Orchard, Suquamish Tribe and other stakehol...

This paper presents the results of experimental work carried out to evaluate the distribution of cold and hot exhaust gas recirculation between cylinders in a DI diesel engine. The experiments have been conducted on a 3.99 liters turbocharged DI diesel engine under full load condition at 1900rpm in order to distinguish and quantify some effects of hot and cooled EGR with various rates on the EG...