Search results for "Testing"
showing 10 items of 1769 documents
A robust calibration methodology for an On-Board Diagnostic car system
2006
New car models are now by law equipped with on-board diagnostic (OBD) systems aimed at monitoring the state of health of strategic components that ensure low levels of polluting exhaust emissions. During development phases, for each new car model, the OBD system must be finely calibrated. This article presents a robust calibration methodology taking into account sources of variability mainly due to production process, operating, and environmental conditions. The methodology enables us to evaluate the false alarm and failure to detect risks intrinsically related to the adopted calibration. An application concerning an upstream oxygen sensor monitored by the OBD is presented.
Experimental study of the evolution of a bar breakage process in a commercial induction machine
2008
This paper analyzes the results of a destructive test developed on a commercial induction motor. The test is designed to reproduce in the laboratory the cage degradation process of an induction motor subjected to a high amount of working cycles, which include heavy startups. During each cycle, the main magnitudes related to the motor condition monitoring are registered, at steady state as well as at transient regime. From these magnitudes, some fault indicators described in the literature are calculated, and so, it is possible to follow their evolution. This analysis assesses the use of such small commercial machines in a test bed as a way of developing a failure that can be used to compare…
Medium Voltage Smart Grid: Experimental Analysis of Secondary Substation Narrow Band Power Line Communication
2013
This paper is focused on the possibility of employing narrow band power line communication (PLC) in medium voltage (MV) distribution networks. The topic is investigated by means of both simulations and experimental tests, which were carried out in the distribution network of Ustica Island. In detail, a two-way MV communication was tested between two secondary substations connected by an MV cable power line. Each substation has a by-pass connection at MV bus-bars and an MV/LV oil filled power transformer. In this paper, the MV and the PLC systems under test are described and the experimental tests are presented, which were carried out to evaluate the parameters of the simulation model. The a…
Test Bench Realization and Application of Specific Working Cycles for the Characterization of Wheelchair Electrical Drives
2006
The life quality of motion disabled people is increased by the use of more and more sophisticated electrical wheelchairs. Despite the diffusion of such aid tools, specific technical standards for the determination of characteristic parameters of their electric drives are not so developed as the ones available for urban electric vehicles. In this paper, in order to define new technical standards for wheelchairs electrical drives, a wheelchair test bench has been purposely carried out. Moreover two specific working cycles, previously conceived and defined by some of the Authors to characterize the performances of the propulsion systems suitable for electrical wheelchair applications, have bee…
Mock-up testing facilities and qualification strategy for EU ITER TBMs
2010
European test blanket modules (TBM) for both European blanket concepts, namely the Helium Cooled Lithium Lead (HCLL) and the Helium Cooled Pebble Bed (HCPB), and their auxiliary systems have been designed in the last years. This paper presents the experimental facilities available in Europe for the qualification tests of European TBMs. In particular, devices designed to analyze specific technological issues, for example corrosion under strong magnetic fields or tritium management and extraction, as well as large scale facility to perform integral tests are described. A preliminary overview on the qualification strategy is presented and discussed.
Compact instrumentation for radiation tolerance test of flash memories in space environment
2010
Aim of this work is the description of a test equipment, designed to be integrated on board of a microsatellite, able to investigate the radiation tolerance of non-volatile memory arrays in a real flight experiment. An FPGA-based design was adopted to preserve a high flexibility degree. Besides standard Program/Read/Erase functions, additional features such as failure data screening and latch-up protection have been implemented. The instrument development phase generated, as a by-product, a non-rad-hard version of the instrument that allowed performing in-situ experiments using 60Co and 10 MeV Boron irradiation facilities on Ground. Preliminary measurement results are reported to show the i…
New method for real-time dynamic focusing through interfaces
2013
[EN] In nondestructive evaluation (NDE) a coupling medium (wedge) is frequently inserted between the array probe and the object being evaluated. In this situation, focal law computing is complicated by the refraction effects at the interface. Furthermore, there are not known techniques to perform dynamic focusing by hardware in these conditions. This work addresses these problems by following a two-step procedure. First, a virtual array that operates in a single medium with nearly equivalent time-of-flight to the foci is obtained. Then, simple hardware is proposed to perform dynamic focusing in real-time. It operates with arrays of any geometry as required by the virtual array in presence o…
Risk Based Inspection Planning for Fatigue Damage in Offshore Steel Structures
2015
High fatigue reliability is one of the most important design criteria for welded offshore steel structures. Due to repeated wave loading fatigue cracks may initiate and grow in welded joints that are important for the integrity of these structures. The present paper presents the methodology and the practical calculations for risk based inspection planning for fatigue cracks in welded details. Due to the uncertainty in the variables involved in the problem the planning has to be carried out by stochastic modeling and risk based assessments. Scatter in potential crack growth has to be analyzed by applied probabilistic facture mechanics and the uncertainty in the performance of the actual insp…
Load-carrying capacity of axially-loaded RC members with circular openings
2012
Abstract Core drilling is today one of the most used technique among the group of partially destructive testing methods in reinforced concrete (RC) members. Even if the engineering practice provided to extract cores only in beams, taking samples from columns could be often necessary. In this case, the presence of the hole introduced a geometrical discontinuity in the member, creating a disturbed region. Consequently, compressive stresses will disperse in lateral direction as they have to avoid the drilled area. A bursting tensile force will develop, in orthogonal direction to the column axis, and if no sufficient reinforcement was arranged, a vertical crack will form, leading to the concret…
Impact of industrial environments on the PC-based measurements
2007
In the paper we present a simple and fast procedure to evaluate the impact of the electromagnetic disturbances, which can be present in the industrial locations, on the measurements performed by a generic PC-based measurement instrument. The method is conceived starting from the data obtained by subjecting the instruments to the disturbances prescribed by the IEC-61326 standard. The results show that, even under heavy disturbances, the common good practices of shielding and grounding allow a correct employment of this kind of instrumentation.