Design of Low-Cost Noise Measurement Sensor Network: Sensor Function Design

In this paper, we report the sensor function design and implementation of a wireless sensor network application for measuring environmental acoustic noise. The system is built on ATmega128 and CC2420 platform. The protocol stack is based on CiNet stack with a global synchronization scheme and supports multi-hop communications. Strict filtering function specified by ITU-R 468 (namely A-weighting) is followed. Both the indoor and outdoor test results were compared with standard sound level meters (CESVA SC-20c and Pulsar94) and showed a less than ±2dB error in both short-term and longterm measurement. Power consumption has been measured that a single AA-type battery can sustain the applicatio…

Road traffic detection using wireless noise sensors

In this paper we present our experimental result of using wireless noise sensor network (WNSN) to detect road traffic. With the features implemented in our network such as multipoint measuring, synchronization, real-time data availability, and strict compliance of sound level meter (SLM) standard IEC 61672:2003, we assert the possibility of using WNSN to detect road traffic, such as vehicle amount, size, and velocity. This application can be extended and integrated as a part of Intelligent Transportation System (ITS).

Promising Dendritic Materials: An Introduction to Hyperbranched Polymers

In nature and universe from living to nonliving things, branching occurs anywhere and anytime, such as the Crab Nebula, forked lightning, river basins, trees, nerves, veins, snow crystals, nervures, and proteoglycan ranging from light-years to kilometers, and to microscale and nanoscales (see Figure 1.1 for selected branching patterns). Hence, branching is a general and important phenomenon that could result in faster and more efficient transfer, dissipation, and distribution of energy and/or matter.

Conclusions and Perspective: Toward Hyperbranched/Dendritic States