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[en] Time Interval Generators (TIGs) are frequently used for the characterizations or timing operations of instruments in particle physics experiments. Though some “off-the-shelf” TIGs can be employed, the necessity of a custom test system or control system makes the TIGs, being implemented in a programmable device desirable. Nowadays, the feasibility of using Field Programmable Gate Arrays (FPGAs) to implement particle physics instrumentation has been validated in the design of Time-to-Digital Converters (TDCs) for precise time measurement. The FPGA-TDC technique is based on the architectures of Tapped Delay Line (TDL), whose delay cells are down to few tens of picosecond. In this case, FPGA-based TIGs with high delay step are preferable allowing the implementation of customized particle physics instrumentations and other utilities on the same FPGA device. A hybrid counting method for designing TIGs with both high resolution and wide range is presented in this paper. The combination of two different counting methods realizing an integratable TIG is described in detail. A specially designed multiplexer for tap selection is emphatically introduced. The special structure of the multiplexer is devised for minimizing the different additional delays caused by the unpredictable routings from different taps to the output. A Kintex-7 FPGA is used for the hybrid counting-based implementation of a TIG, providing a resolution up to 11 ps and an interval range up to 8 s.
[en] Are illustrated the new technology for natural gas on-line measurement systems, telemetry and data transmission systems
[it]L'interesse per le tecnologie di telelettura dei contatori dimostrato dalle aziende distributrici e' in continua crescita. Qui di seguito vengono analizziate le attuali proposte del mercato, proponendo una serie di soluzioni che si caratterizzano per i benefici offerti
[en] Underground spaces are now being given attention to exploit for transportation, utilities, and public usage. The underground has become a spider's web of utility networks. Mapping of underground utility pipelines has become a challenging and difficult task. As such, mapping of underground utility pipelines is a ''hit-and-miss'' affair, and results in many catastrophic damages, particularly in urban areas. Therefore, this study was conducted to extract locational information of the urban underground utility pipeline using trenchless measuring tool, namely ground penetrating radar (GPR). The focus of this study was to conduct underground utility pipeline mapping for retrieval of geometry properties of the pipelines, using GPR. In doing this, a series of tests were first conducted at the preferred test site and real-life experiment, followed by modeling of field-based model using Finite-Difference Time-Domain (FDTD). Results provide the locational information of underground utility pipelines associated with its mapping accuracy. Eventually, this locational information of the underground utility pipelines is beneficial to civil infrastructure management and maintenance which in the long term is time-saving and critically important for the development of metropolitan areas
[en] We present an initial review of a novel through-focus scanning optical microscopy (TSOM pronounced as 'tee-som') imaging method that produces nanometer-dimensional measurement sensitivity using a conventional bright-field optical microscope. In the TSOM method a target is scanned through the focus of an optical microscope, acquiring conventional optical images at different focal positions. The TSOM images are constructed using the through-focus optical images. A TSOM image is unique under given experimental conditions and is sensitive to changes in the dimensions of a target in a distinct way. We use this characteristic for nanoscale-dimensional metrology. This technique can be used to identify the dimension which is changing between two nanosized targets and to determine the dimensions using a library-matching method. This methodology has potential utility for a wide range of target geometries and application areas, including nanometrology, nanomanufacturing, defect analysis, inspection, process control and biotechnology
[en] Capacitive beam position monitors are non-interceptive devices providing signals from injection till extraction of beam from a synchrotron. Their typical usage is for the orbit or turn-by-turn position measurements of a bunched beam. In this contribution, we will discuss their utility in the *other beam states* such as during injection, debunching, unbunched state, during rf gymnastics and potentially while beam is being extraction. The influence of BPM signal processing on utilizing BPM signals in aforementioned cases will be highlighted.
[en] Hydroxyl tagging velocimetry (HTV) is characterized for the first time at extended pressures (1 and 3 atm) and temperatures (295 K to 673 K) in an attempt to improve measurement precision for low speed flows. While previous investigations have focused on ambient and flame temperatures (1400 K), the present study investigates between these two extreme conditions, wherein both the local chemistry and thermodynamic state of the gas may hinder or aid the functionality of the technique. Effects of temperature and pressure on the hydroxyl (OH) excitation spectrum are assessed and compared to simulations to determine the optimal laser frequency, and OH species lifetime and tracer line diffusion are examined to determine the relative efficiency of the photo-dissociation process and the quality of the resulting signal. A two-fold increase in the photo-dissociation efficiency is observed at elevated temperatures. Tag line spread was found to be dominated by shear rather than molecular diffusion. Velocity measurement precision was characterized for time delays ranging from 5 μs to 3.2 ms and was found to be inversely proportional to the time delay selected, supporting the need for the extended tracer lifetimes observed at higher temperatures when used for low-velocity applications. Velocity profiles measured in heated jets of nitrogen and air indicate measurement uncertainties as low as 0.1 m (at confidence level), while comparison with particle image velocimetry (PIV) measurements showed peak deviations in the observed velocity profiles to be less than . The results suggest the high utility of HTV at making measurements in low-velocity flows at moderate temperatures. (paper)
[en] Physical protection system is a very important system in nuclear facilities. According definition of international atomic energy authority, it is entity of protecting measures, designed in order to prevent unauthorized removal radiological sabotage of nuclear materials or facilities. Physical protection system involves the use of multiple layers of interdependent systems which include CCTV surveillance, access control, control panel, computers devices and many other types of equipments. Physical protection system is involving very sensitive electronic equipments. And these sensitive equipments are affected by any power disturbance which may lead to an equipments failure, erratic operation of sensitive devices; malfunction and error signals lead to bad performance of the system. Normally, there are several disturbances exceed the thresholds. Among of all electrical power disturbances, harmonic distortion and voltage fluctuations (flicker) are disturbances that cause most problems to sensitive equipment. Harmonic distortion originates in the nonlinear characteristics of devices and loads in the power system. It is also common to use a single quantity, the Total Harmonic Distortion (THD) as a measure of the effective value of harmonic distortion. One of the major problems related to harmonic disturbances is harmonic resonance, the resonance can magnify harmonic distortions to a level that can damage the equipment or cause equipment malfunction. Other effects of harmonics are equipment overloading and increase losses lead to overheating and equipment failure. Voltage fluctuations are cyclical variations in the voltage rms value or a series of random voltage changes, whose magnitude does not normally exceed voltage ranges of 0.9 p.u. to 1.1 p.u. A common phenomenon of voltage fluctuations is flicker. Arc furnaces and welders are the most common causes of voltage fluctuations in utility transmission and distribution systems. It causes lamps light to blink rapidly and causes erratic operation of sensitive equipment. So, it is necessary to mitigate power disturbances and feed physical protection system equipments with suitable electric source according to standards to maintain accurate operation and good performance of the system. The present research discusses impact of power disturbances such as; voltage, current or frequency deviation may result in failure or malfunction of sensitive equipment. A case study is done; field data is collected by real time analyzer and analyzed with reference to standards. And also problems are analyzed. Solution techniques are suggested all sensitive and critical equipments should be fed through separate eclectic circuits. And these circuits should isolate by using isolation transformer and fed through double conversion uninterruptible power supply to protect the sensitive equipments and hence achieve high efficiency of the system. Isolation transformer is used to maximize the power quality benefits of a standard transformer when transferring electrical power from an AC current source to any equipment. Shielded isolation transformer is very popular powerconditioning devices. It isolates sensitive loads from transients and noise caused by the utility. They can also keep harmonics produced by end-user nonlinear equipment from getting onto the utility’s system. The on-line or double conversion UPS, is the ultimate in UPS protection because the utility supply power does not flow directly to the load like the other types of UPS. Instead, the power flows continuously through a charger/rectifier that feeds both a storage battery and an inverter. The inverter generates AC power to the load being protected. In the event of a power failure, the inverter is fed by the battery. Since the power flows through the rectifier and inverter before reaching the load, most power disturbances are eliminated through constant filtering. Therefore, double conversion UPS is a good idea for any system which is sensitive to transients, noise, and/or cannot tolerate any power interruption. It has all its power flow continuously through the input rectifier and DC voltage link. Hence, most disturbances on the input are isolated from the output. The bypass for this system may be used to take the UPS out of service. The present work also discuss and analysis of power disturbances and their effects on physical protection system equipments. And also show a design of modern technique to protect the sensitive equipment from power disturbances to keep good and accurate operation of the system and economic calculation. Security of radioactive material is very important and physical security system is very necessary for prevention and detection. This paper presents the bad effects of power quality problems on the behavior of the physical protection system in nuclear facility. The analysis of the recorded data yields that, harmonics and flickers are the most severe events and should be taken in consideration for any evaluation. It is recommended that mitigation technique should be done to keep good performance and accurate operation of the physical protection system and then void operation problems. to mitigate power problems a design of modern technique will be done to protect the sensitive equipment from power disturbances to keep good and accurate operation of the system. and also economic calculation will present. (author)
[en] An ion mobility mass spectrometry apparatus for investigating the photoisomerization and photodissociation of electrosprayed molecular ions in the gas phase is described. The device consists of a drift tube mobility spectrometer, with access for a laser beam that intercepts the drifting ion packet either coaxially or transversely, followed by a quadrupole mass filter. An ion gate halfway along the drift region allows the instrument to be used as a tandem ion mobility spectrometer, enabling mobility selection of ions prior to irradiation, with the photoisomer ions being separated over the second half of the drift tube. The utility of the device is illustrated with photoisomerization and photodissociation action spectra of carbocyanine molecular cations. The mobility resolution of the device for singly charged ions is typically 80 and it has a mass range of 100-440 Da, with the lower limit determined by the drive frequency for the ion funnels, and the upper limit by the quadrupole mass filter
[en] At reduced dimensions the electrical transport properties of materials often depend on the measurement direction. Here we report on a measurement setup designed on the manual insertion utility probe (MIUP) of the Quantum Design’s magnetic property measurement system (MPMS) to measure anisotropic transport properties in the temperature range of 10–400 K and magnetic fields up to 5 Tesla. The setup is capable of measuring the Seebeck coefficient and electrical resistivity both along and perpendicular to the applied magnetic field. The Seebeck measurement is based on the differential measurement technique; the four-probe electrical resistivity measurement can easily be performed on the opposite side of the setup. The setup consists of a small copper cube (5 × 5 × 5 mm3) fitted with diagonally cut electrically insulated square strips. The strips are fitted with copper-constantan thermocouple in differential arrangement for the temperature-gradient (ΔT) measurement and symmetrically arranged surface mount (SM) resistors to create the ΔT across the sample. The cube can be rotated to alter the direction of the applied magnetic field on the sample. We demonstrate the directional dependence of the measured transport properties for a normal platinum wire and for single crystal flakes of CuCr2Se4. (paper)