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Distributed, high-density spatiotemporal observations are proposed for answering many river-related questions, including those pertaining to hydraulics and multi-dimensional river modeling, geomorphology, sediment transport and riparian habitat restoration. We present here a case study of an autonomous, high-resolution robotic spatial mapping of cross-sectional velocity and salt concentration in a river basin. Several experiments for analyzing the spatial and temporal trends at multiple cross-sections of the San Joaquin River were performed during the campaign from August 21-25, 2006. Preliminary analysis from these experiments illustrating the range of investigations is presented. Lessons learned during the campaign are discussed to provide useful insights for similar robotic investigations in aquatic environments.

This paper reports the first application of actuated sensing systems for high spatiotemporal resolution characterization of the threedimensional environment of river and lake aquatic systems. The development of a new method and its verification in these two application areas is described. Both applications involve dynamic phenomena - one resulting from flow of the water and the other from rapidly evolving biological processes. These applications are typical environmental monitoring problems. They exemplify the key challenge in such problems - characterizing phenomena displaying spatiotemporal heterogeneity. In many such examples, the application requires a diverse array of measurements based on sensors for physical, chemical and biological systems. Together, these requirements pose a significant challenge for conventional sensor network methods. We describe the development and applications of a new general purpose method for actuated sensing - Iterative experiment Design for Environmental Applications (IDEA). IDEA introduces a new in-field adaptation of the sensing systems including static and actuated sensors. IDEA addresses the limitations of previous sampling approaches, for example conventional adaptive sampling, by guiding adaptive sampling with an iteratively developed phenomenon model. This paper presents applications of IDEA to: (1) Three-dimensional characterization of contaminant concentration and flow at the confluence of two major rivers; and (2) Characterization of phytoplankton dynamics in a lake system. These applications provide ideal tests by presenting complex structures associated with each phenomenon and enabling a comprehensive evaluation of the general applicability of IDEA methodology. Improved performance using guided adaptive sampling is demonstrated for two existing methodologies, stratified adaptive sampling and hierarchical non-stationary Gaussian Processes. The IDEA experimental results both validate the general applicability of this method and also have advanced the understanding of interrelated physical, chemical and biological processes in these sampled environments.

Environmental monitoring has proven to be a rich source of biological and ecological data but typically does not conform to traditional monitoring techniques. Events of interest are often dynamic and may not tolerate the introduction of a conventional infrastructure without disrupting the environment being monitored. The new NIMS architectures require minimal infrastructure, are rapidly deployable, and have self anchoring coordinate systems. Simple cableways provide system mobility with minimal occlusion of the monitored transect allowing for accurate positioning and high positional resolution within the space of interest. These new systems have been developed to operate in either a two dimensional plane (NIMS-RD: e.g. monitor river or stream properties) or in a three dimensional volume (NIMS-3D: e.g. monitor incident solar radiation under a forest canopy).

In order to understand and control the impact of non-point source pollution in Central California and many semi-arid regions of the world, a multiscale observational network focused on several water quality issues is proposed. Specifically, we are targeting the main stem of the San Joaquin River as a prototypical river system. By developing multiscale modeling approaches, we will endeavor first to understand the hydrodynamics of salt mixing on the San Joaquin at each of the three river confluences (with the Merced, Tuolumne, and Stanislaus Rivers) and create salt-flow rating curves characterizing 5 different flow conditions, and second, to quantify and sample groundwater-surface water interactions along critical reaches of the river where the US Geological Survey is investigating with respect to groundwater accretion.

Purpose: Using Activity Theory as an interpretive lens to examine the distribution of leadership, this paper shares a case study on how leadership for an ICT project was distributed in a Singapore school. Method: The case study involved observations of 49 meetings and 34 interviews of leaders and the teachers who were involved in the ICT project. Findings: Applying the lens of third-generation Activity Theory helped to reveal two main interrelated activity systems, and the leadership actions performed by senior and middle management. The two activity systems comprised the school and the ICT project. The focus in Activity Theory on the social-cultural perspective highlighted the role played by social norms in mediating the leadership activity. Implications for future research: The conclusion focuses on the understanding of distributed leadership as analysed through the lens of Activity Theory and suggests future research directions. Activity Theory enables research on distributed leadership to identify and examine interrelated activity systems that various leaders are involved in, and how these impact the leadership provided.

Following in the footsteps of the field Networked Infomechanical Systems (NIMS) currently deployed at the James San Jacinto Mountain Reserve in Idyllwild California, two smaller scale NIMS architectures have emerged. The Laboratory Systems (NIMS-LS) provides an experimental testbed for verification of actuated sensing of environmental phenomena. The NIMS-LS System also includes emulation of environmental phenomena (i.e. light distribution in ecosystems). The Rapidly Deployable (NIMS-RD) platform provides a flexible means of sampling environmental phenomena directly with minimal infrastructure, rapid deployability and minimal impact on the environment. NIMS-RD has been deployed at the James San Jacinto Mountain Reserve, Medea Creek in the Santa Monica Mountains, Merced River in Merced CA and White Mountains Research Station near Bishop CA.

Rapidly growing stress on the natural environment has created an urgent demand for new environmental exploration systems that operate remotely and autonomously. As sensor networks are applied to these critical environmental monitoring problems, a series of new requirements have emerged for extensive characterization of dynamic phenomena in three-dimensional environments. The unpredictable presence of obstacles to sensing and the inherent temporal evolution of events create limitations for optimal deployment of sensors in the environment. Networked Infomechanical Systems (NIMS) technology has been developed to introduce precise and sustainable actuation for distributed sensing. NIMS devices are suspended on cable infrastructure to provide a combination of broad range motion combined with accurate localization.

The impacts of anthropogenic inputs on streams in urban watersheds include seasonal algal blooms, high bacteria levels, elevated nutrient concentrations, and altered channel morphology, all of which are commonplace in southern California urban streams. Although it is clear that urbanization effects stream health, the complex mechanisms leading to symptoms such as elevated algal biomass are not well understood. In order to better understand the relationship between urbanization and stream health, the temporal and spatial variation of stream water parameters in urban streams need to be known. Understanding these patterns will help elucidate the driving mechanisms leading to stream degradation and allow for improved management practices. Using various water quality sensors and NIMS technology, the temporal (daily, weekly, and monthly) and spatial (cross sectional and reach scale) variation in Medea Creek in Agoura Hills, CA is being monitored. By analyzing the correlations between these parameters we will be able to determine the driving biotic and abiotic mechanisms leading to the excess algal biomass and nutrient concentrations in Medea Creek.

Rapidly growing stress on the natural environment has created an urgent demand for new environmental exploration systems that operate remotely and autonomously. As sensor networks are applied to these critical environmental monitoring problems, a series of new requirements have emerged for extensive characterization of dynamic phenomena in three-dimensional environments. The unpredictable presence of obstacles to sensing and the inherent temporal evolution of events create limitations for optimal deployment of sensors in the environment.

2005 CENS Summer Intern:NIMS (Networked Info-Mechanical Systems) is a sensor system utilizing fixed and actuated sensors to monitor environmental changes. A new, rapidly deployable NIMS (NIMS RD) allows for more mobility and versatility in the field. With short-term deployments, data is able to be read quickly and in-field calibrations are possible. A variety of sensor nodes can be attached to the system allowing it to work in diverse environments. As a result of this, many deployments have been possible and much environmental data has been collected at Medea Creek, the James Reserve, and the White Mountains.

Cool ambient air temperatures and warm soil and rock surfaces in alpine fellfield ecosystems produce sharp and dynamic spatial gradients in surface temperatures, with profound impacts on plant ecophysiology. Spot measurements of plant and soil surface temperatures are not sufficient to understand the complexity of this environment. Thermal scanner instrumentation mounted on a NIMS-RD system can provide dense measurements of spatial and temporal patterns of surface temperatures across a fellfield habitat, as well as a photographic log of transect position.

The ability to remotely monitor the dynamics of a natural environment is an increasingly important avenue for investigating and ultimately protecting natural ecosystems and safeguarding public health. NIMS provides a new capability for mobile monitoring of complex environments. NIMS enables the first spatiotemporally resolved sensing capability for applications including microclimate characterization in the forest canopy by using this new multisensor module.