Low-Cost Visual Sensor Node for BlueTooth-Based Measurement Networks

This paper proposes a wireless visual sensor comprising of a low-cost grayscale camera as the sensing hardware and a BlueTooth (BT) 100-m slave module as the transmission hardware. The latter enables the sensor to be inserted as a node in a medium-range BT measurement network. The proposed sensor, which is designed to satisfy precise specifications in terms of image-transfer rate and power consumption, represents a good image-acquisition solution in a wide range of applications where hardwiring between camera and image processor is undesired. This paper describes the hardware used and the overall operating principle behind the sensor, discusses the sensor-node performance, and reports the results of reliability tests

Performance Characterization of a Wireless Instrumentation Bus

The architecture and operation of a wireless instrumentation bus based on the Bluetooth standard are presented together with a detailed characterization. The bus, via suitable wireless interface boards, allows measurement instruments equipped with standard RS232, IEEE488, universal serial bus, and local area network interface ports to be simply connected within the wireless area without any firmware modification. In addition, a comparison with traditional wired interface buses is carried out in terms of communication reliability and throughput with reference to some basic operating modes. Finally, the results of distance tests and a detailed evaluation of power consumption for each wireless interface module are reported. This will enable measurement system designers to evaluate the convenience of the solution for their application requirements

Software customization to provide digital oscilloscope with enhanced period-measurement features

This paper tackles the problem of signal period measurements by means of oscilloscopes. First, the performance of two last-generation scopes, implementing a zero-crossing algorithm, is evaluated. Then, after a brief resume of alternative measurement techniques, a solution to enhance the period-measurement capability of scopes is proposed and implemented in the LeCroy WaveMaster 8620A software. Finally, the results of the tests carried out on different signal waveforms are reported and analyzed

Smart Devices and Services for Smart City

Citizen quality of life can be improved through facilities and services that have been thought to ease citizen interaction with municipal authorities, offices and structures. All technologies and devices, used for developing these facilities, are the pillars of the Smart City idea: a City that adapts itself, at least in part, to citizens’ needs. Advanced Metering Infrastructure (AMI) could become the backbone of all the smart city projects. Other public services can be loaded on AMI’s to be smart and thus helping to find the affordability of investments. The paper deals with this topic by describing devices and results of a pilot project, which has been carried out in an Italian middle city (Salerno), to experience the use of RF 169MHz wM-bus based AMI. Experimental results regarding a set of about 2500 installed devices for gas and water metering, car parking management and elder tele-assistance, will be reported in detail to show convenience and problems of this approach

Mixed Graph of Terms: Beyond the bags of words representation of a text

The main purpose of text mining techniques is to identify common patterns through the observation of vectors of features and then to use such patterns to make predictions. Vectors of features are usually made up of weighted words, as well as those used in the text retrieval field, which are obtained thanks to the assumption that considers a document as a "bag of words". However, in this paper we demonstrate that, to obtain more accuracy in the analysis and revelation of common patterns, we could employ (observe) more complex features than simple weighted words. The proposed vector of features considers a hierarchical structure, named a mixed Graph of Terms, composed of a directed and an undirected sub-graph of words, that can be automatically constructed from a small set of documents through the probabilistic Topic Model. The graph has demonstrated its efficiency in a classic "ad-hoc" text retrieval problem. Here we consider expanding the initial query with this new structured vector of features