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Csaba F. Hajdu, Tamás Dabóczi, Christos Zamantzas
ON-LINE SYSTEM SUPERVISION OF BEAM LOSS MONITORING SYSTEMS WITH SINUSOIDAL EXCITATION

The project related to this paper is aimed at the design and implementation of a process providing a continuous and comprehensive supervision of the beam loss monitoring (BLM) signal chain at the European Organization for Nuclear Research (CERN), a feature no particle accelerator currently has. This paper reports on the background of the project, the current best solution to the problem, the measurements done to lay the foundations of the new implementation and the suggested new setup of the on-line diagnostic process.

Sai Hou, Buren Mandula, Wei Quan, Sahdev Kumar, Hideo Furuhashi
IMAGING OF AN ULTRASONIC WAVE REFLECTED BY AN OBJECT USING AN ACOUSTIC LENS IN AIR

We have investigated the imaging of an ultrasonic wave reflected by an object using an acoustic lens in air. The reflected ultrasonic wave is focused by a spherical acoustic lens on an ultrasonic array sensor having 32 ultrasonic receivers. We have designed and manufactured the acoustic lens, which has a diameter of 25 cm. The imaging of the ultrasonic wave is demonstrated experimentally. This approach does not require delay-and-sum operation and can be operated using a small amount of memory. Therefore, load calculation is decreased.

Andrea Cataldo, Egidio De Benedetto, Giuseppe Cannazza, Emanuele Piuzzi
PRACTICAL IMPLEMENTATION OF DIFFUSED SENSING ELEMENTS FOR TDR-BASED MONITORING OF RISING DAMP IN BUILDING STRUCTURES

This paper describes the operating and technical details of the practical implementation of an innovative time domain reflectometry (TDR)-system for monitoring rising damp in building structures. The proposed system employs wire-like, passive, diffused sensing elements (SE’s) that are embedded, at the time of construction or renovation, inside the walls of the building to be monitored. The SE’s remain permanently inside the wall, ready to be interrogated when necessary.

M. Pexa, B. Peterka, J. Marik, J. Cedik, L. Weinfurtner
INFLUENCING THE QUALITY OF HOSPITAL BEDS USING VIBRO-ACOUSTIC DIAGNOSTIC

Human health is one of the most precious gifts that each person has. This gift need to take a maximum protection. The human, when has health problems, seeks to restore satisfactory health condition with a significant contribution of medical care. Medical care has used various means to restore human health.
A hospital bed as highly sophisticated technical equipment is one of many such means used during treatment. Hospital bed allows appropriate positioning of the patient, so as to improve health status and complications occurred in the form of pressure sores. Also the patient comfort is one of the important task of properly working bed. Patient's comfort can be compromised by increased vibration and noise levels generated by actuators of bed and other movable parts of bed assembly.
This paper describes utilization of noise and vibration measurement in particular case of Linet Eleganza hospital bed. Obtained results of measurements are used for future redesigning of the actuator assembly. Influence of taken changes are also enumerated.

M. Catelani, L. Ciani, A. Fossi, A. Giorgi, A. Battistone, C. D’Adamo, G. Fioriti
MEDIUM VOLTAGE POWER LINES: OUTAGES DATA ANALYSIS AND MODELLING

Obtaining a reliable model that takes into account the counting nature of outages occurrence in Medium Voltage (MV) lines is a very prominent issue for Distribution System Operators (DSO). As a matter of fact in distribution system planning and management, accurate assessment of reliability performance is essential for making informed decisions. In addition, performance based regulation directs towards a more deep understanding of differences in reliability performance between networks. In this paper two Negative Binomial regression models are proposed for modelling yearly long and short duration outages occurrence in MV feeders; consequently a Monte Carlo simulation is performed in order to obtain a confidence interval for the yearly number of interruptions in a collection of feeders. The results are compared to real failure data from a distribution cluster of feeders in Italy.

I. Baldanzi, M. Catelani , L. Ciani , M. K. Kazimierczuk , A. Luchetta , S. Manetti , A. Reatti
MLMVNN FOR PARAMETERS FAULTS DETECTION IN A DC-DC BOOST CONVERTER

This paper aims to propose an effective approach in the fault diagnosis based on neural networks. In particular, a MultiLayer based on MultiValued Neuron artificial Neural Network (MLMVNN) with a complex QR-decomposition is used to identify parameters values changing (i.e. faults detection) on a Boost converter starting from voltages and currents in steady state measurements.

Piotr Bilski
APPLICATION OF RANDOM FOREST TO THE FAULT DETECTION IN ANALOG CIRCUITS

The paper presents the application of the Random Forest (RF) to the diagnostics of analog circuits. The modified structure of the forest proposed for the task and its generation algorithm is presented. The approach is used to detect parametric faults in the fifth order lowpass filter. Multiple versions of the forest are tested. The proposed method is also confronted against the decision tree, being superior over the traditional classifier. The future prospects of the approach are considered.

Chan-Na Xu, Liang Hu, Xin Fu
A METHOD TO DETERMINE INFULUENCE OF MULTIPHASE FLOW ON VIBRATION CHARATERISTICS OF CORIOLIS MASS FLOWMETER’S MEASURING TUBE

Coriolis mass flowmeter (CMF) is a preference for mass flow rate measurement for its high accuracy. However, with multiphase flow, CMF has deducted accuracy and is prone to fail due to the lack of stable vibration of measuring tube, which is the premise of CMF’s accurate measurement. This paper presents a method to determine the influence of multiphase on vibration characteristics of CMF’s measuring tube. At first, the measuring tube with multiphase flow is drove at a series of frequencies to obtain its frequency responses. Then transfer function of the vibration system is identified by amplitude-frequency curve fitting and phase-frequency curve fitting. At last, vibration characteristics of the measuring tube with multiphase flow are derived from the transfer function. To verify this method, experiments of pure water, gas, and gas/liquid flow are conducted and the results are presented. Discussions and conclusions about influence of multiphase flow on measuring tube’s vibration characteristics have been carried out and are expected to lay the foundation of vibration control for CMF in multiphase flow. Further research about the vibration characteristics of any type of measuring tube with various multiphase flows such as solid/liquid flow and heavy oil can be conducted with the method presented in this paper.

Wu Jian, Nikolay Semin
DEVELOPMENT THE PRIMARY VELOCITY STANDARD FOR THE CALIBRATION OF LDA SYSTEM

Air velocity measurements are required to have the measurement traceability to the SI unit of length and time. This can be realised through the setup of a primary velocity standard. NMC has designed and developed the primary velocity standard using the spinning disc for the calibration of an LDA system. The system is capable of measuring the velocity from 0.2 m/s to 40 m/s with the measurement uncertainty of 0.1% to 0.4% of reading.

E. von Lavante, Harun Kaya
NUMERICAL INVESTIGATION OF TRANSITIONAL BEHAVIOR IN CRITICAL FLOW VENTURI NOZZLES

The flow fields in two toroidal Venturi nozzles operating at critical conditions have been investigated using numerical flow simulation. The present study focused on the transitional effects in the boundary layer, occuring in critical flow Venturi nozzles (CFVN) with shapes that might not confirm to the ISO 9300 standard. Two intake geometries were studied, with a well-tested transition criterium being applied. The nozzles displayed in most cases delayed transition at Reynolds numbers higher than indicated in the ISO 9300 standard.

Page 363 of 977 Results 3621 - 3630 of 9762