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P. V. Vehviläinen, H. A. T. Ihalainen
ESTIMATING THE ACTIVATION FUNCTIONS OF AN MLP-NETWORK

The most common neural network type is a multilayer perceptron (MLP) network. Even a relatively simple MLP-network requires usually high computational accuracy and efficiency. The usual types of activation functions are not necessarily applicable for a neural network algorithm used in microcontrollers. For this purpose a new type of activation function is introduced.

O. Postolache, M. D. Pereira, P. Girão, M. Cretu, C. Fosalau
APPLICATION OF NEURAL STRUCTURES IN WATER QUALITY MEASUREMENTS

The paper presents a theoretical and practical study related with the implementation of artificial intelligence for the enhancement of water quality measurement systems accuracy. The measurement parameters related to water quality (WQ), considered in the present work, are essentially the pH and the conductivity (C). The fusion of sensor information is performed using two different architectures of the Artificial Neural Networks. Those architectures are compared in terms of the implementation, complexity of associated digital signal processing and accuracy enhancement. An additional measure of temperature is used to offer details regarding the presence of micro-organisms in tested water and also to compensate the temperature influences on the pH and C measurements. The test environment is implemented by a virtual measurement system, which includes a hardware component based on a data acquisition board and a software component developed in LabVIEW graphical programming language.

M. Kotani, K. Akazawa, S. Ozawa, H. Matsumoto
DETECTION OF LEAKAGE SOUND BY USING MODULAR NEURAL NETWORKS

It is important to detect the leakage of the gas to be flammable or poisonous from the cracks in pipes of petroleum refining plants or chemical plants. We examined the application of modular neural networks to the acoustic diagnosis technique for the leakage sound. The modular neural network has the ability to adapt its structure according to the environment. Experiments were performed for an artificial gas leakage device with various experimental conditions to imitate the change of environment for a long term. The discrimination accuracy with the proposed network was observed to be about 93%, which was better than 83% with the simple network. From the results, we confirmed the effectiveness for the application of the modular neural network to the detection of the leakage sound for the practical use.

O. Ivakhiv, A. Kowalczyk, R. Velgan
INTELLIGENT PROGRAMMABLE MEASUREMENT SYSTEM

The semantic redundancy decreasing sources totality self-programmable system is analyzed. The source flexible sampling program changing threshold value and the channel capacity demand equations founded. The software packet system realization was prepared, the operating simulation was made.

E. Benoit, L. Foulloy, J Tailland
AUTOMATIC SMART SENSORS GENERATION BASED ON INOMS

This paper presents a new modelisation of smart sensors based on a representation of the sensor by it‘s INternal Operating Modes (INOMs) and by services uses or it proposes. Sensor INOM relies on internal states of the sensor and is characterized by the set of sensor services that can be activated when the mode is active. The software of the sensor is automatically derived from the modelisation. This approach permits sensor designer to use their skill on the transducer and on the sensor service definition instead of losing time on the writing of the sensor software.

H. Stadtmann, J. Fellinger, K. J. Velbeck, C. Schmitzer, J. E. Rotunda, E. Michler
A NEW USER-FRIENDLY EXTREMITY DOSIMETRY SYSTEM – DESIGN, COMPARISON, AND TESTING

A new extremity TLD system has been developed and tested that provides for user convenience and automated processing while meeting various accreditation requirements. The design is a result of successful collaboration among organisational entities in different countries and included research centres, users, and the manufacturer. The primary consideration was to meet the needs of the medical market, without losing sight of the needs of research laboratories and power plants. This dosimetry system design provides various detector designs based on the need to measure photons or betas. Beyond the fundamental need for accurate dosimetry, the system meets the customers need for a versatile and comfortable ring and provides for both hot and cold sterilisation.
The system represents a unique integration of components comprising the finger ring, dosimeter and dosimeter identification system, and TLD Instruments. The dosimeter identification system in the TLD Reader incorporates a CCD Camera and Machine Vision Technology to interpret the circular bar codes used to quickly and accurately identifies each individual dosimeter. Portability of this dosimetry system has been realised with the adaptation into multiple TLD Instruments.

A. Zanobini, F. Doretti
GSM COVERAGE MEASUREMENT ON RADIO EXTENDER SYSTEM FOR RAILWAYS TUNNEL

In this paper a short introduction to the radio coverage system for railway tunnels realised on the line Prato–Bologna, is presented. GSM coverage measurements have been conducted on three different installations. For a better results interpretation the employed measurement system has been described. Moreover measurement execution and physic characteristics of the analysed tunnels are shown. Finally results are discussed and some conclusions are drawn.

F. Tegtmeier, M. Peters
DETERMINATION OF STRUCTURAL DAMAGE TO BUILDINGS USING MICROSENSORS BASED ON STRAIN GAUGE TECHNOLOGY

In the supervision of buildings and structures, to guarantee the support strength and to detect structural damage due to ageing and varied utilisation at an early stage and at low cost, special measuring instruments are increasingly being developed. An important tool in the measuring techniques applied to determine loads and detect damage are strain gauge-based microsensors. These can protect the integrated precision resistance foils from the adverse ambient conditions prevailing in the vicinity of the structure and can easily be attached to the structure subject to supervision.
Investigations carried out within the scope of the project have so far concentrated on problems concerning the integration of the sensor into the structure. Work has been focused on both, a suitable design of the sensor and an appropriate selection of measurement points ensuring low impact on the structure, the possibility of subsequent attachment to existing objects, and high signal amplitudes in the case of changes in the built volumes. Investigations into potential applications of the sensors were carried out on the basis of a theoretical description and by practical experiments, simulating the structures' environment using suitable dummy structures and load transmitters. They are used to test the measuring method and, above all, to establish a matrix for the transfer of exactly defined states of external stress and strain to the strain gauges enclosed inside the sensor.

W. Steinchen, G. Kupfer, P. Mäckel
VIBRATION ANALYSIS BY DIGITAL SHEAROGRAPHY

Digital Shearography, a laser interferometric technique in conjunction with the digital image processing, has the potential for vibration analysis due to its simple optical system and insensitivy against small rigid body motions. This paper will focus on its recent developments for vibration analysis and for nondestructive testing (NDT) by dynamic (harmonic) excitation. With the introduction of real time observation using automatically refreshing reference frame, both small and large rigid body motions are greatly suppressed. The development of a smaller and more mobile measuring device in conjunction with a user guided comfortable program Shearwin enables the digital shearography to be applied easily as an industrial on line testing tool.

C. Adam, A. Hruska, M. Kofler
ELASTIC STRUCTURES WITH TUNED LIQUID COLUMN DAMPERS

The influence of Tuned Liquid Column Dampers (TLCDs) on the dynamic response of structures is investigated experimentally. The experimental models consist of a small-scale plane one-storey shear frame, made of aluminum, with a TLCD attached to its rigid beam. TLCDs are rigidly constructed of plastic tubes and filled with liquid (water). Performing free vibration experiments the geometry of the TLCD container and length of the liquid in the TLCD are varied. In the second series of experiments investigations with time-harmonic loading (frequency sweeps) are performed, where an electromagnetic shaker excites the structure's base. The natural frequencies of the frame and the TLCD are tuned by modifying the length of the liquid. The optimal tuning ratio and the optimal geometry of the container are determined.

Page 577 of 977 Results 5761 - 5770 of 9762