Showing papers on "Wireless sensor network published in 1990"
Patent•
16 May 1990
TL;DR: A self-powered sensor for a closed-loop security system includes a switch-actuating signal upon the detection of a physical condition as mentioned in this paper, which is connected between the positive and negative poles of a closed loop security system and opens the loop upon receiving of the switch-acting signal thereby triggering an alarm.
Abstract: A self-powered sensor for a closed-loop security system includes a self-powered sensor network which provides a switch-actuating signal upon the detection of a physical condition. An electronic switch, which is in a normally closed position, is connected between the positive and negative poles of a closed-loop security system and opens the loop upon receipt of the switch-actuating signal thereby triggering an alarm. The self-powered sensor network may include a voltage doubler for converting the AC output of a transducer to a DC voltage of an amplitude sufficient to open the switch. When the switch is opened, voltage from the closed-loop security system becomes available to power a visible or audible alarm identifying the sensor that opened the loop.
35 citations
01 Jan 1990
TL;DR: By postulating hypothetical delay elements, it is shown how a laterally inhibited sensor net can function as a tunable low-pass filter and provide filters appropriate for sensory input to motor learning.
Abstract: The higher vertebrates seem to make use of three kinds of highly redundant sensing: (1) duplicate sensing, e.g. having two eyes, (2) fusory sensing, e.g. seeing and touching the same object, and (3) distributed sensing, e.g. networks of sensors in the skin. In this paper we focus on distributed sensing and its connections to learning. The dominant feature of distributed sensor networks is lateral inhibition, where each sensor drives down each of its neighbors in proportion to its own excitation. Lateral inhibition has been widely recognized by biologists as a mechanism for contrast enhancement. By postulating hypothetical delay elements, we show how a laterally inhibited sensor net can function as a tunable low-pass filter. Thus distributed sensor networks’ dynamic properties provide filters appropriate for sensory input to motor learning.
14 citations
05 Feb 1990
TL;DR: In this paper, the authors describe the work and the main results which have been obtained since then, and three main areas have been covered which have concerned the implementation of a coherence based parallel quasi- distributed sensing system, the simultaneous measurement of temperature and strain and the mechanical properties of composite material with embedded sensor.
Abstract: A collaborative European Programme N degree(s) RI 1B 0173-C(CD) under the auspices of BRITE (Basic Research in Industrial Technologies for Europe), jointly sponsored by the Commission of the European Communities and European Industry, was launched in 1988 to explore and develop an optical sensor network embedded in composite for measuring the strain and temperature distributions. Its objectives and first results were presented at the `Fiber Optic Smart Structures and Skins II' conference (Sept. 1989, Boston). This paper will describe the work and the main results which have been obtained since then. Three main areas have been covered which have concerned the implementation of a coherence based parallel quasi- distributed sensing system, the simultaneous measurement of temperature and strain and the mechanical properties of composite material with embedded sensor. All results have shown the high interest of such an optical sensing network for structure monitoring.
9 citations
01 Feb 1990
TL;DR: Advanced architectures for distributed sensor networks are discussed, including the development of efficient algorithms for data-combination, noise removal, and information abstraction, and fault-tolerance capabilities within the proposed signal processing architecture.
Abstract: In this paper, we discuss advanced architectures for distributed sensor networks. This includes the development of efficient algorithms for data-combination, noise removal, and information abstraction. Specifically, the we discuss the following issues in distributed signal processing: *A new signal processing architecture for networking spatially distributed sensors. *An improved method for integration of sensor information. *Fault-tolerance capabilities within the proposed signal processing architecture.
5 citations
Patent•
11 May 1990
TL;DR: In this article, the authors describe a network of fiber-optic intrinsic sensors and a return bus formed from optical fibres, where the outputs of the sensors are coupled to the return bus.
Abstract: The network of the invention comprises conventional sensors (24) and fibre-optic intrinsic sensors (31, 32). It is optically supplied (19, 23). It comprises a circuit for addressing the sensor channels to active couplers (27) which are also optically supplied. Each conventional sensor is associated with an integrated optical element (28 to 30). All the outputs of the sensors are coupled to a return bus (37) formed from optical fibres.
4 citations
01 Aug 1990
TL;DR: The analog design and implementation of these small-scale networks demonstrates the feasibility of implementing more complicated ANNs in electronic hardware and can also be designed for VLSI implementation.
Abstract: This paper deals with the analog implementation of neocognitron based neural networks. All of Fukushima''s and related work on the neocognitron is based on digital computer simulations. To fully take advantage of the power of this network paradigm an analog electronic approach is proposed. We first implemented a 6-by-6 sensor network with discrete analog components and fixed weights. The network was given weight values to recognize the characters U L and F. These characters are recognized regardless of their location on the sensor and with various levels of distortion and noise. The network performance has also shown an excellent correlation with software simulation results. Next we implemented a variable weight network which can be trained to recognize simple patterns by means of self-organization. The adaptable weights were implemented with PETs configured as voltage-controlled resistors. To implement a variable weight there must be some type of " memory" to store the weight value and hold it while the value is reinforced or incremented. Two methods were evaluated: an analog sample-hold circuit and a digital storage scheme using binary counters. The latter is preferable for VLSI implementation because it uses standard components and does not require the use of capacitors. The analog design and implementation of these small-scale networks demonstrates the feasibility of implementing more complicated ANNs in electronic hardware. The circuits developed can also be designed for VLSI implementation. 1.
3 citations
01 Oct 1990
TL;DR: In this article, an assessment of numerous activities in the field of multisensor target recognition reveals several trends and conditions which are cause for concern and suggests suggestions for additional investigation and guidance for current activities with respect to some of the identified concerns.
Abstract: An assessment of numerous activities in the field of multisensor target recognition
reveals several trends and conditions which are cause for concern. .These
concerns are analyzed in terms of their potential impact on the ultimate employment
of automatic target recognition in military systems. Suggestions for additional
investigation and guidance for current activities are presented with respect to some
of the identified concerns.
2 citations
TL;DR: Reliability requirements for low-cost sensor networks and criteria to increase their reliability are discussed and three well-known field bus standards are analysed and compared regarding their influence on the reliability of sensor networks.
Abstract: Reliability requirements for low-cost sensor networks and criteria to increase their reliability are discussed. The specifications of OSI layers 0 to 2 of three well-known field bus standards (BITBUS, DIN Measurement bus, Profibus) are analysed and compared regarding their influence on the reliability of sensor networks.
TL;DR: In this paper, a remote transducer telemetry system utilizing an optical link for electrical isolation and EMI immunity has been developed, which is capable of interfacing resistance-, capacitance-, and voltage-type sensors.
Abstract: A remote-transducer telemetry system utilizing an optical link for electrical isolation and EMI (electromagnetic interference) immunity has been developed. The system is capable of interfacing resistance-, capacitance-, and voltage-type sensors. Descriptions of each module making up the system are presented. Experimental results show that a system accuracy of 1% is achieved. The EMI immunity and passive characteristic of this system can readily be used to improve the performance of a conventional two-wire electronic-based sensor telemetry system. Given the increasing demand for a multiple-sensor monitoring system, the single sensor system can easily be configured for sensor network application. >