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With funding from the Water Equipment and Policy Center, Joshi, professor emeritus of electrical and computer engineering, is developing a meter that more accurately measures the flow of fluids — such as water — using ultrasonic waves. “There are several companies making ultrasonic meters,” Joshi says. “But they’re still expensive compared with the conventional meters. One of our aims is to lower the cost.” boards (known as microcantilevers), Josse says — whose vibration changes when they contact specific molecules. His current work entails making systems more sensitive so they can detect contamination at levels matching pollution standards. The project is also striving to better distinguish the “signal” — the accurate reading — from the “noise” — all the factors that can interfere with or distort the data. “Every time we think we’ve solved this problem, something else has come up,” Josse says. A wide variety of other projects is under way at Marquette as well. One that particularly intrigues Zitomer is a study to identify the makeup of the microbial populations being used in about 50 different industrial, municipal and agricultural treatment “digesters” — the vats that house the microbes and treat the waste. The goal is to establish which ones are the fastest and most effective. Surprisingly, he notes, there isn’t an established “recipe” of microbes; new plants using the technology typically populate their digesters with a colony from another plant. Advances in technology and basic scientific knowledge are changing the field dramatically, Zitomer notes, triggered in large part by the lessons in examining DNA that was derived from the human genome studies. “The tools to understand the microbial community evolve very quickly and keep changing,” he says. “We can do so much more than we could 15 years ago.” And he’s upbeat about prospects for the discipline, particularly at Marquette. “I just see the future as very bright for developing more sustainable wastewater technologies here,” Zitomer says.

To use ultrasound to measure water flow, a pair of ultrasonic transducers is placed on opposite sides of the pipe carrying the water. One transducer generates a sound wave at a frequency typically around 1 MHz (the highest frequency most humans can hear is about 20 kHz). The time it takes for the sound wave to travel through the pipe and the water in it varies with the speed of the water, allowing the system to measure the speed, and therefore the volume, of water passing by. Joshi’s version is still in the research and development stage. He expects it will take about one to two years to come up with a laboratory prototype ready for testing and that commercial availability could be about two to three years away.


It’s not the same as cleaning water, but Dr. Shrinivas Joshi’s work contributes to water-system sustainability in another way.

Dr. Shrinivas Joshi Professor Emeritus, Electrical and Computer Engineering

Measuring Up

Until now, cost has been “the major stumbling block” in using ultrasonic measurement, Joshi says. “We’ve lowered the cost and made it wireless.” The product also has been developed to operate without requiring a power supply, saving more money. And, he says, it will also benefit from longevity. Mechanical water meters tend to wear out over time, and utility regulators often require replacing them every 10 years to protect consumers from inaccurate readings. “The meter we’re developing has no moving parts,” Joshi says. “You may not have to replace the meter for a very long time.”

clean water

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Discover Research 2014  

Every spring DISCOVER: Marquette University Research and Scholarship showcases some of the most interesting research happening on Marquette'...

Discover Research 2014  

Every spring DISCOVER: Marquette University Research and Scholarship showcases some of the most interesting research happening on Marquette'...