Date Added: Jan 2011
Wireless sensor networks generate a vast amount of data. This data, however, must be sparingly extracted to conserve energy, usually the most precious resource in battery powered sensors. When approximation is acceptable, a model-driven approach to query processing is effective in saving energy by avoiding contacting nodes whose values can be predicted or are unlikely to be in the result set. However, to optimize queries such as top -k, reasoning directly with models of joint probability distributions can be prohibitively expensive.