Meeting ecologists' requirements with adaptive data acquisition

Abstract

Ecologists instrument ecosystems to collect time series representing the evolution in time and space of relevant abiotic and biotic factors. Sensor networks promise to improve on existing data acquisition systems by interconnecting stand-alone measurement systems into virtual instruments. Such ecological sensor networks, however, will only fulfill their potential if they meet the scientists requirements. In an ideal world, an ecologist expresses requirements in terms of a target dataset, which the sensor network then actually collects and stores. In fact, failures occur and interesting events happen, making uniform systematic ecosystem sampling neither possible nor desirable. Today, these anomalous situations are handled as exceptions treated by technicians that receive an alert at deployment time. In this paper, we detail how ecological sensor networks can maximize the utility of the collected datasets in a changing environment. More specifically, we present the design of a controller that continuously maintains its state based on the data obtained from the sensor network (as well as external systems), and configures motes with parameters that satisfy a constraint optimization problem derived from the current state, the system requirements, and the scientist requirements. We describe our implementation, discuss its scalability, and discuss its performance in the context of two case studies.

A cyber physical networking system for monitoring and cleaning up blue-green algae blooms with agile sensor and actuator control mechanism on Lake Tai

“…Not all the data acquired by the users can be transmitted to the base station. In [7], the authors proposed ADAE, a utility-based controller that adaptively configures motes in a changing environment. ADAE presents three-tier architecture to organize the complexity of communicating with motes, representing the sensor network state and the user requirements, generating constraint optimization problems to determine the configuration parameters.…”

“…Recent research works [5][6][7] have shown the abilities to reconfigure the parameters of sensors according to the changing environment. Usually, the control mechanism in these papers maintains its state based on the data obtained from the sensors and configures the remote devices with parameters that satisfy a constraint optimization problem derived from the current system state and the requirements of users.…”

Monitoring in a High-Arctic Environment: Some Lessons from MANA

“…By solving this COP we obtain a set of actions which adaptively changes the sampling strategy based on the scientist's requirements. For further details we refer the reader to [2].…”

“…2 For ten years, a long-term monitoring program has focused on the water chemistry and occurrence of freshwater biota in two small lakes during summer. These measurements, however, do not adequately describe the processes in the lakes, especially not in the periods when the lakes are covered with ice.…”

Dynamic power management for long-term energy neutral operation of solar energy harvesting systems

“…A broad range of application scenarios, e.g., [9,11,22,24], benefit from a minimum supported performance level that can be sustained over time periods on the order of multiple years. A system enhanced with energy harvesting capabilities canin theory -operate indefinitely as the energy store can be replenished periodically.…”