This article discusses the issues of creating a technology for non-destructive quality testing of soldered joints of heat exchangers for the development of an automated non-destructive testing ...system. The object of testing (having a complex geometric shape) is described, the relevance of the development and the problems of manufacturing and testing by existing testing methods are substantiated. Typical defects (cold lap, dry joint) that occur in soldered joints during the manufacture of heat exchangers are described. Applicable methods of non-destructive testing (pulse-echo and through-transmission methods) are analyzed, existing solutions are analyzed, advantages and disadvantages of each of the methods are identified. The problems of manual implementation of ultrasonic testing methods are analyzed, the need to automate the testing process is substantiated, and solutions to the main issues that arise when creating automated non-destructive testing systems for objects of complex geometric shape are presented.
Particle physics experiments often require the simultaneous reconstruction of many interaction vertices. Usually, this problem is solved by ad hoc heuristic algorithms. We propose a universal ...approach to address the multiple vertex finding through a principled formulation as a minimum-cost lifted multicut problem. The suggested algorithm is tested in a typical LHC environment with multiple proton-proton interaction vertices. Reconstruction errors caused by the particle detectors complicate the solution and require the introduction of special metrics to assess the vertex-finding performance. We demonstrate that the minimum-cost lifted multicut approach outperforms heuristic algorithms and works well up to the highest vertex multiplicity expected at the LHC.
This paper discusses the issues of development of an algorithm for the movement of the measuring module of an automated system for non-destructive quality testing of the solder joints of the engine ...nozzle. The object of testing is identified as a one with a complex geometric shape, the flaws in soldered joints of the test object occur during the manufacturing process. Defects studied in this paper are: «dry joint», «partial dry joint» and «cold lap». The relevance of the development, as well as the problems of production and testing of engine nozzles, which do not allow to identify the required defects at the early stages of manufacturing assembly units without destroying the integrity of the engine nozzle, are substantiated. The existing approaches are described in terms of the choice of methods and means for non-destructive testing of engine nozzles of complex geometric shapes, their advantages and disadvantages are identified. The existing problems in terms of automation of the pulse-echo and through-transmission methods of ultrasonic testing are analysed, the advantages and disadvantages of the proposed methods are identified. The main factors that reduce the probability of detecting defects are determined, namely, the instability of the acoustic contact between the transducer and the test object, as well as the deviation of the acoustic axis of the transducer from the normal to the surface of the test object. The requirements for the motion algorithm of the measuring module of an automated non-destructive testing system with feedback based on the signal amplitude measured during scanning from the structural elements of the internal structure of the engine nozzle are determined.
In anticipation of the first LHC data to come, a considerable effort has been devoted to ensure the efficient reconstruction of vertices in the ATLAS detector. This includes the reconstruction of ...photon conversions, long lived particles, secondary vertices in jets as well as finding and fitting of primary vertices. The implementation of the corresponding algorithms requires a modular design based on the use of abstract interfaces and a common Event Data Model. An enhanced software framework addressing various physics applications of vertex reconstruction has been developed in the ATLAS experiment. Presented in this paper are the general principles of this framework. A particular emphasis is given to the description of the concrete implementations, which are dedicated to diverse methods of vertex reconstruction.
3D-FBK Pixel Sensors: Recent Beam Tests Results with Irradiated Devices Micelli, A.; /INFN, Trieste /Udine U.; Helle, K. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2012, Letnik:
650, Številka:
1
Journal Article
Recenzirano
The Pixel Detector is the innermost part of the ATLAS experiment tracking device at the Large Hadron Collider, and plays a key role in the reconstruction of the primary vertices from the collisions ...and secondary vertices produced by short-lived particles. To cope with the high level of radiation produced during the collider operation, it is planned to add to the present three layers of silicon pixel sensors which constitute the Pixel Detector, an additional layer (Insertable B-Layer, or IBL) of sensors. 3D silicon sensors are one of the technologies which are under study for the IBL. 3D silicon technology is an innovative combination of very-large-scale integration and Micro-Electro-Mechanical-Systems where electrodes are fabricated inside the silicon bulk instead of being implanted on the wafer surfaces. 3D sensors, with electrodes fully or partially penetrating the silicon substrate, are currently fabricated at different processing facilities in Europe and USA. This paper reports on the 2010 June beam test results for irradiated 3D devices produced at FBK (Trento, Italy). The performance of these devices, all bump-bonded with the ATLAS pixel FE-I3 read-out chip, is compared to that observed before irradiation in a previous beam test.
The results of a partial wave analysis of 3π system produced in the reaction
π
−
A →
π
+
π
−
π
−
A at the momentum of 36.6 GeV/c on beryllium target are presented. Resonant signals from
a′
1(1750),
a
...3(1860),
a
4(2050) are observed in different channels. Small bump at
M ≈ 1.6GeV in the exotic wave
J
PC
M
η
= 1
−+1
+ is seen. The combined analysis of VES data on this wave in η′π,
b
1(1235)
π and ϱπ channels points to the existence of a hybrid meson with
M ≈ 1.6 GeV.
Resonances in the {omega}{omega} system Amelin, D. V.; Bugg, D. V.; Gavrilov, Yu. G. ...
Physics of atomic nuclei,
04/2006, Letnik:
69, Številka:
4
Journal Article
Recenzirano
Results of a partial-wave analysis for the reaction {pi}{sup -} {sup {yields}} {omega}{omega}n studied at the VES spectrometer (Institute for High Energy Physics, Protvino) are presented. The ...behavior of the J{sup PC} = 2{sup ++} amplitudes in the {omega}{omega} system is described by the f{sub 2}(1565) and f{sub 2}(1910) resonances, whose parameters were fixed at M = 1.590 {+-} 0.010 GeV and {gamma} = 0.140 {+-} 0.011 GeV for the former and at M = 1.890 {+-} 0.010 GeV and {gamma} = 0.165 {+-} 0.019 GeV for the latter. The decay f{sub 4}(2050) {sup {yields}} {omega}{omega} was observed at parameters values of M = 1.960 {+-} 0.015 GeV, {gamma} = 0.290 {+-} 0.020 GeV.
Problems arising in debugging distributed heterogeneous systems are considered, and some methods for their solution are discussed. The paper is based on the experience obtained when developing ...debugging tools in the framework of studies conducted in the Institute of System Studies, Russian Academy of Sciences.
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