Systems and methods for detecting normal levels of bacteria in water using a multiple angle light scattering (MALS) instrument

A system for monitoring normal levels of bacteria in liquid, the system comprising:

• an optical axis;
• a target zone, the optical axis intersecting the target zone;
• at least one light source configured to generate a light beam and direct the light beam through the target zone;
• an optic lens system configured to collect light scattered by a particle associated with the bacteria in the liquid medium in the target zone and direct the scattered light to at least one detector, the detector configured to detect the light and generate a digital signal;
• and
• a computer system coupled with the detector, the computer system configured to execute a set of programmed instructions to identify and classify the particle and generate an alarm, the instructions causing the computer system to:
• extract events from the digital signal,
• calculate the similarity between the extracted event and a known event,
• classify the event based on the similarity,
• calculate a plurality of count rates for the classification type,
• store the plurality of count rates,
• calculate a trend in the stored plurality of count rates, and
• generate an alarm if the trend is undesirable,
• wherein the instructions are further configured to cause the computer system to extract events by causing the computer system to perform a mean amplitude calculation on the normalized frame.

A system for monitoring normal levels of bacteria in liquid, the system comprising:

• an optical axis;
• a target zone, the optical axis intersecting the target zone;
• at least one light source configured to generate a light beam and direct the light beam through the target zone;
• an optic lens system configured to collect light scattered by a particle associated with the bacteria in the liquid medium in the target zone and direct the scattered light to at least one detector, the detector configured to detect the light and generate a digital signal;
• and
• a computer system coupled with the detector, the computer system configured to execute a set of programmed instructions to identify and classify the particle and generate an alarm, the instructions causing the computer system to:
• extract events from the digital signal,
• calculate the similarity between the extracted event and a known event,
• classify the event based on the similarity,
• calculate a plurality of count rates for the classification type,
• store the plurality of count rates,
• calculate a trend in the stored plurality of count rates, and
• generate an alarm if the trend is undesirable,
• wherein the instructions are further configured to cause the computer system to precondition the extracted events by causing the computer system to generate a normalized array of events, each event of the array of events comprising a standard orientation, and to adjust the mean value of each event in the array of events.

A system for monitoring normal levels of bacteria in liquid, the system comprising:

• an optical axis;
• a target zone, the optical axis intersecting the target zone;
• at least one light source configured to generate a light beam and direct the light beam through the target zone;
• an optic lens system configured to collect light scattered by a particle associated with the bacteria in the liquid medium in the target zone and direct the scattered light to at least one detector, the detector configured to detect the light and generate a digital signal;
• and
• a computer system coupled with the detector, the computer system configured to execute a set of programmed instructions to identify and classify the particle and generate an alarm, the instructions causing the computer system to:
• extract events from the digital signal,
• calculate the similarity between the extracted event and a known event,
• classify the event based on the similarity,
• calculate a plurality of count rates for the classification type,
• store the plurality of count rates,
• calculate a trend in the stored plurality of count rates, and
• generate an alarm if the trend is undesirable,
• wherein the instructions are further configured to cause the computer system to extract features from the extracted events by causing the computer system to generate a normalized array of events, each event of the array of events comprising a standard orientation, and to use the entire frame corresponding to each event in the array of events for extraction.