LANSCE-R WIRE-SCANNER ANALOG FRONT-END ELECTRONICS

International Nuclear Information System (INIS)

Gruchalla, Michael E.

2011-01-01

A new AFE is being developed for the new LANSCE-R wire-scanner systems. The new AFE is implemented in a National Instruments Compact RIO (cRIO) module installed a BiRa 4U BiRIO cRIO chassis specifically designed to accommodate the cRIO crate and all the wire-scanner interface, control and motor-drive electronics. A single AFE module provides interface to both X and Y wire sensors using true DC coupled transimpedance amplifiers providing collection of the wire charge signals, real-time wire integrity verification using the normal dataacquisition system, and wire bias of 0V to +/-50V. The AFE system is designed to accommodate comparatively long macropulses (>1ms) with high PRF (>120Hz) without the need to provide timing signals. The basic AFE bandwidth is flat from true DC to 50kHz with a true first-order pole at 50kHz. Numeric integration in the cRIO FPGA provides real-time pulse-to-pulse numeric integration of the AFE signal to compute the total charge collected in each macropulse. This method of charge collection eliminates the need to provide synchronization signals to the wire-scanner AFE while providing the capability to accurately record the charge from long macropulses at high PRF.

Linac beam core modeling from wire-scanner data

International Nuclear Information System (INIS)

Law, A.G.

1977-08-01

This study introduces mathematical modeling of accelerator beams from data collected by wire scanners. Details about a beam core D(x,x',y,y') are examined in several situations: (a) for a discretization of the projection into xy-space, a maximum-entropy solution and a minimum-norm solution are developed and discussed, (b) for undiscretized xy-subspace, a two-dimensional Gaussian approximation D(x,.,y,.) = a exp [α(x-x 0 ) 2 + β(x-x 0 )(y-y 0 ) + γ(y-y 0 ) 2 ] is obtained by least squares, and (c) for four-dimensional space, the fit of a single Gaussian to data from a succession of wire scanners is investigated

Accuracy of four different digital intraoral scanners: effects of the presence of orthodontic brackets and wire.

Science.gov (United States)

Jung, Yoo-Ran; Park, Ji-Man; Chun, Youn-Sic; Lee, Kkot-Nim; Kim, Minji

The objective of this study was to compare the accuracy of four different digital intraoral scanners and the effects of buccal brackets and orthodontic wire. For this study, three sets of models (Control model, BKT model with buccal bracket, and WBKT model with buccal bracket and orthodontic wire) were scanned using four different types of intraoral scanners: E4D dentist, iTero, Trios, and Zfx IntraScan. The mesiodistal width of the teeth, intercanine width, and intermolar width measured by four scanners were compared. Three-dimensional (3D) images of the brackets were taken using the four scanners. Data were analyzed with one-way ANOVA, independent t test, and post-hoc Tukey test at a significance level of P brackets and orthodontic wire. Comparison of 3D bracket images scanned by the four scanners showed differences in image distortion among the scanners. Bracket characteristics did not affect the 3D bracket images. The four intraoral scanners used in this study differed in accuracy. However, the results acquired by iTero and Trios were more reliable. Effects of buccal brackets and orthodontic wire on the 3D images taken by intraoral scanners were not clinically significant.

Vibrating wire for beam profile scanning

Directory of Open Access Journals (Sweden)

S. G. Arutunian

1999-12-01

Full Text Available A method that measures the transverse profile (emittance of the bunch by detecting radiation arising at the scattering of the bunch on scanning wire is widely used. In this work information about bunch scattering is obtained by measuring the oscillation frequency of the tightened scanning wire. In such a way, the system of radiation (or secondary particles extraction and measurement can be removed. The entire unit consists of a compact fork with tightened wire and a scanning system. Normal oscillation frequency of a wire depends on wire tension, its geometric parameters, and, in a second approximation, its elastic characteristics. Normal oscillations are generated by interaction of an alternating current through the wire with magnetic field of a permanent magnet. In this case, it is suggested that the magnetic field of the accelerator (field of dipole magnets or quadrupole magnets be used for excitation of oscillations. The dependence of oscillation frequency on beam scattering is determined by several factors, including changes of wire tension caused by transverse force of the beam and influence of beam self-field. Preliminary calculations show that the influence of wire heating will dominate. We have studied strain gauges on the basis of vibrating wire from various materials (tungsten, beryl bronze, and niobium zirconium alloys. A scheme of normal oscillation generation by alternating current in autogeneration circuit with automatic frequency adjustment was selected. A special method of wire fixation and elimination of transverse degrees of freedom allows us to achieve relative stability better than 10^{-5} during several days at a relative resolution of 10^{-6}. Experimental results and estimates of wire heating of existing scanners show that the wire heats up to a few hundred grades, which is enough for measurements. The usage of wire of micrometer thickness diminishes the problem of wire thermalization speed during the scanning of the bunch.

Superharp: A wire scanner with absolute position readout for beam energy measurement at CEBAF

International Nuclear Information System (INIS)

Yan, C.

1994-01-01

Superharp is an upgrade CEBAF wire scanner with absolute position readout from shaft encoder. As high precision absolute beam position probe (Δx ∼ 10μm), three pairs of superharps are installed at the entrance, the mid-point, and the exit of Hall C arc beamline in beam switch yard, which will be tuned in dispersive mode as energy spectrometer performing 10 -3 beam energy measurement. With dual sensor system: the direct current pickup and the bremsstrahlung detection electronics, beam profile can be obtained by superharp at wide beam current range from 1 μA to 100 μA

LANSCE wire scanning diagnostics device mechanical design

International Nuclear Information System (INIS)

Rodriguez Esparza, Sergio

2010-01-01

The Los Alamos Neutron Science Center (LANSCE) is one of the major experimental science facilities at the Los Alamos National Laboratory (LANL). The core of LANSCE's work lies in the operation of a powerful linear accelerator, which accelerates protons up to 84% the speed oflight. These protons are used for a variety of purposes, including materials testing, weapons research and isotopes production. To assist in guiding the proton beam, a series of over one hundred wire scanners are used to measure the beam profile at various locations along the half-mile length of the particle accelerator. A wire scanner is an electro-mechanical device that moves a set of wires through a particle beam and measures the secondary emissions from the resulting beam-wire interaction to obtain beam intensity information. When supplemented with data from a position sensor, this information is used to determine the cross-sectional profile of the beam. This measurement allows beam operators to adjust parameters such as acceleration, beam steering, and focus to ensure that the beam reaches its destination as effectively as possible. Some of the current wire scanners are nearly forty years old and are becoming obsolete. The problem with current wire scanners comes in the difficulty of maintenance and reliability. The designs of these wire scanners vary making it difficult to keep spare parts that would work on all designs. Also many of the components are custom built or out-dated technology and are no longer in production.

LANSCE wire scanning diagnostics device mechanical design

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Esparza, Sergio [Los Alamos National Laboratory

2010-01-01

The Los Alamos Neutron Science Center (LANSCE) is one of the major experimental science facilities at the Los Alamos National Laboratory (LANL). The core of LANSCE's work lies in the operation of a powerful linear accelerator, which accelerates protons up to 84% the speed oflight. These protons are used for a variety of purposes, including materials testing, weapons research and isotopes production. To assist in guiding the proton beam, a series of over one hundred wire scanners are used to measure the beam profile at various locations along the half-mile length of the particle accelerator. A wire scanner is an electro-mechanical device that moves a set of wires through a particle beam and measures the secondary emissions from the resulting beam-wire interaction to obtain beam intensity information. When supplemented with data from a position sensor, this information is used to determine the cross-sectional profile of the beam. This measurement allows beam operators to adjust parameters such as acceleration, beam steering, and focus to ensure that the beam reaches its destination as effectively as possible. Some of the current wire scanners are nearly forty years old and are becoming obsolete. The problem with current wire scanners comes in the difficulty of maintenance and reliability. The designs of these wire scanners vary making it difficult to keep spare parts that would work on all designs. Also many of the components are custom built or out-dated technology and are no longer in production.

Fast and High Accuracy Wire Scanner

CERN Document Server

Koujili, M; Koopman, J; Ramos, D; Sapinski, M; De Freitas, J; Ait Amira, Y; Djerdir, A

2009-01-01

Scanning of a high intensity particle beam imposes challenging requirements on a Wire Scanner system. It is expected to reach a scanning speed of 20 m.s-1 with a position accuracy of the order of 1 μm. In addition a timing accuracy better than 1 millisecond is needed. The adopted solution consists of a fork holding a wire rotating by a maximum of 200°. Fork, rotor and angular position sensor are mounted on the same axis and located in a chamber connected to the beam vacuum. The requirements imply the design of a system with extremely low vibration, vacuum compatibility, radiation and temperature tolerance. The adopted solution consists of a rotary brushless synchronous motor with the permanent magnet rotor installed inside of the vacuum chamber and the stator installed outside. The accurate position sensor will be mounted on the rotary shaft inside of the vacuum chamber, has to resist a bake-out temperature of 200°C and ionizing radiation up to a dozen of kGy/year. A digital feedback controller allows maxi...

A fast wire scanner, used to measure the transverse density distribution of beams circulating in an accelerator or storage ring.

CERN Multimedia

Maximilien Brice

2002-01-01

Fast wire scanners are used to measure the transverse density distribution of beams circulating in an accelerator or storage ring. In order to minimize blow-up of the beam through multiple Coulomb scattering, the wires are very thin (in the version shown here it is actually a twisted strand of carbon fibres with a total diameter of about 25 microns) and are swept through the beam at high speed (a linear motor, not mounted here, accelerates the wires to up to 20 m/s). One measures either the secondary emission current from the wire, or the signal from a scintillator/photomultiplier combination downstream from the wire scanner receiving the shower from nuclear reactions of beam particles with the wire nuclei. There are four such fast wire scanners in the 26 GeV PS and eight in the 1.4 GeV Booster.

Performance assesment of pre-series beam wire scanner prototypes for the LHC injectors upgrade

CERN Document Server

AUTHOR|(CDS)2243534

The BEAM department (BE), is in charge of the development and operation of the accelerator components. Inside this department, the Beam Instrumentation group (BE-BI) works on the instruments that allows the operators and scientists to observe the accelerated beam and its characteristics. Finally, the Profile Measurement section (BE-BI-PM) deals with all the instruments capable of measuring the particles transverse distribution (often called transverse beam profile). Among the different systems developed and maintained by the section, the Beam Wire Scanners (BWS) are particularly relevant, because ensures the accurate beam profile measurements in all the circular accelerators and serves as calibration for other instruments. A total of 31 BWS are installed in the PS, PSB, SPS and LHC (see Fig. 1 to recognize the different accelerators). All of these instruments present a different design, depending on their location, and are not satisfying the HL-LHC needs. In order to harmonize the CERN’s BWS with a single d...

Mechanical Design and Evaluation of the MP-11-Like Wire Scanner Prototype

International Nuclear Information System (INIS)

Rodriguez Esparza, Sergio; Sedillo, James Daniel; Maestas, Alfred J.; Gilpatrick, John D.; Smith, Brian G.; Raybun, Joseph L.; Martinez, Jason P.; Sattler, F.D.; Gruchalla, Michael E.

2012-01-01

A wire scanner (WS) is a linearly actuated diagnostic device that uses fiber wires (such as Tungsten or Silicon Carbide) to obtain the position and intensity profile of the proton beam at the Los Alamos Neutron Science Center (LANSCE) particle accelerator. LANSCE will be installing approximately 86 new WS in the near future as part of the LANSCE Risk Mitigation project. These 86 new WS include the replacement of many current WS and some newly added to the current linear accelerator and other beam lines. The reason for the replacement and addition of WS is that many of the existing actuators have parts that are no longer readily available and are difficult to find, thus making maintenance very difficult. One of the main goals is to construct the new WS with as many commercially-available-off-the-shelf components as possible. In addition, faster beam scans (both mechanically and in term of data acquisition) are desired for better operation of the accelerator. This document outlines the mechanical design of the new MP-11-like WS prototype and compares it to a previously built and tested SNS-like WS prototype.

Mechanical Design and Evaluation of the MP-11-Like Wire Scanner Prototype

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Maestas, Alfred J. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory; Raybun, Joseph L. [Los Alamos National Laboratory; Martinez, Jason P. [Los Alamos National Laboratory; Sattler, F. D. [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory

2012-05-16

A wire scanner (WS) is a linearly actuated diagnostic device that uses fiber wires (such as Tungsten or Silicon Carbide) to obtain the position and intensity profile of the proton beam at the Los Alamos Neutron Science Center (LANSCE) particle accelerator. LANSCE will be installing approximately 86 new WS in the near future as part of the LANSCE Risk Mitigation project. These 86 new WS include the replacement of many current WS and some newly added to the current linear accelerator and other beam lines. The reason for the replacement and addition of WS is that many of the existing actuators have parts that are no longer readily available and are difficult to find, thus making maintenance very difficult. One of the main goals is to construct the new WS with as many commercially-available-off-the-shelf components as possible. In addition, faster beam scans (both mechanically and in term of data acquisition) are desired for better operation of the accelerator. This document outlines the mechanical design of the new MP-11-like WS prototype and compares it to a previously built and tested SNS-like WS prototype.

Wire scanner data analysis for the SSC Linac emittance measurement

International Nuclear Information System (INIS)

Yao, C.Y.; Hurd, J.W.; Sage, J.

1993-07-01

The wire scanners are designed in the SSC Linac for measurement of beam emittance at various locations. In order to obtain beam parameters from the scan signal, a data analysis program was developed that considers the problems of noise reduction, machine modeling, parameter fitting, and correction. This program is intended as a tool for Linac commissioning and also as part of the Linac control program. Some of the results from commissioning runs are presented

Lansce Wire Scanning Diagnostics Device Mechanical Design

International Nuclear Information System (INIS)

Rodriguez Esparza, Sergio; Batygin, Yuri K.; Gilpatrick, John D.; Gruchalla, Michael E.; Maestas, Alfred J.; Pillai, Chandra; Raybun, Joseph L.; Sattler, F.D.; Sedillo, James Daniel; Smith, Brian G.

2011-01-01

The Accelerator Operations and Technology Division at Los Alamos National Laboratory operates a linear particle accelerator which utilizes 110 wire scanning diagnostics devices to gain position and intensity information of the proton beam. In the upcoming LANSCE improvements, 51 of these wire scanners are to be replaced with a new design, up-to-date technology and off-the-shelf components. This document outlines the requirements for the mechanical design of the LANSCE wire scanner and presents the recently developed linac wire scanner prototype. Additionally, this document presents the design modifications that have been implemented into the fabrication and assembly of this first linac wire scanner prototype. Also, this document will present the design for the second, third, and fourth wire scanner prototypes being developed. Prototypes 2 and 3 belong to a different section of the particle accelerator and therefore have slightly different design specifications. Prototype 4 is a modification of a previously used wire scanner in our facility. Lastly, the paper concludes with a plan for future work on the wire scanner development.

Lansce Wire Scanning Diagnostics Device Mechanical Design

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Batygin, Yuri K. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Maestas, Alfred J. [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Raybun, Joseph L. [Los Alamos National Laboratory; Sattler, F. D. [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

2011-01-01

The Accelerator Operations & Technology Division at Los Alamos National Laboratory operates a linear particle accelerator which utilizes 110 wire scanning diagnostics devices to gain position and intensity information of the proton beam. In the upcoming LANSCE improvements, 51 of these wire scanners are to be replaced with a new design, up-to-date technology and off-the-shelf components. This document outlines the requirements for the mechanical design of the LANSCE wire scanner and presents the recently developed linac wire scanner prototype. Additionally, this document presents the design modifications that have been implemented into the fabrication and assembly of this first linac wire scanner prototype. Also, this document will present the design for the second, third, and fourth wire scanner prototypes being developed. Prototypes 2 and 3 belong to a different section of the particle accelerator and therefore have slightly different design specifications. Prototype 4 is a modification of a previously used wire scanner in our facility. Lastly, the paper concludes with a plan for future work on the wire scanner development.

MR-guided breast biopsy and hook wire marking using a low-field (0.23 T) scanner with optical instrument tracking

International Nuclear Information System (INIS)

Blanco Sequeiros, Roberto; Reinikainen, Heli; Blanco Sequeiros, Andreas M.; Ojala, Risto; Paeaekkoe, Eija; Tervonen, Osmo; Vaara, Teuvo

2007-01-01

The purpose of this study was to evaluate the technical feasibility of MR-guided percutaneous breast biopsy (LCNB) and breast hook wire marking in a low-field (0.23 T) MRI system with optical instrument tracking. MR-guided core biopsy and/or hook wire marking was performed on 13 lesions observable at MR imaging only. Seven breast LCNBs and 10 hook wire markings were performed under MR guidance on 11 patients. The diagnosis was confirmed by excision biopsy or mastectomy in 12 lesions and with histopathological and cytological diagnosis and 12-month clinical follow-up in one lesion. All lesions seen in the high-field scanner were also successfully identified and targeted in the low-field scanner. The following procedures were typically technically successful. There were difficulties due to unsatisfactory functioning of some core biopsy guns. Detailed description of low-field MR guidance and optical tracking in breast biopsies is provided. The procedure seems accurate and safe and provides means to obtain a histological diagnosis of a breast lesion only seen with MRI. The low-field biopsy system is comparable to the high-field MRI system. MR-compatible biopsy guns need to be improved. (orig.)

Flying wire beam profile monitor at the J-PARC MR

International Nuclear Information System (INIS)

Igarashi, Susumu; Arakawa, Dai; Hashimoto, Yoshinori; Teshima, Masaki; Toyama, Takeshi; Hanamura, Kotoku

2008-01-01

A flying wire beam profile monitor has been assembled and installed at the main ring of the Japan Proton Accelerator Research Complex. The monitor is to measure the horizontal beam profile using a carbon fiber of 7 μmφ. The fiber crosses the beam with the speed of 10 m/s. Secondary particles from the beam-wire scattering is detected using a scintillation counter. The scintillator signal as a function of the wire position is to be reconstructed as a beam profile. The high scanning speed and the minimum material are necessary for the accurate beam profile measurement. The monitor has been operated in the beam commissioning run of the main ring. The beam profile data have been successfully acquired after the reduction of the beam background. (author)

Beam profile measurement with flying wires at the Fermilab Recycler Ring

Energy Technology Data Exchange (ETDEWEB)

Carcagno, R.; Pishchalnikov, Yu.; Krider, J.; Hu, M.; Lorman, E.; Marchionni, A.; Pordes, S.; Wilson, P.; Zagel, J.; /Fermilab

2005-05-01

Flying wires were installed at the Fermilab Recycler Ring for transverse beam profile measurement for both proton and antiproton beams. The following note describes the system configuration, calibration and resolution of the flying wire system, interactions between the wires and the beam, as well as analysis of the transverse beam profile in the presence of a stochastic cooling system.

Beam profile measurement with flying wires at the Fermilab Recycler Ring

International Nuclear Information System (INIS)

Carcagno, R.; Pishchalnikov, Yu.; Krider, J.; Hu, M.; Lorman, E.; Marchionni, A.; Pordes, S.; Wilson, P.; Zagel, J.

2005-01-01

Flying wires were installed at the Fermilab Recycler Ring for transverse beam profile measurement for both proton and antiproton beams. The following note describes the system configuration, calibration and resolution of the flying wire system, interactions between the wires and the beam, as well as analysis of the transverse beam profile in the presence of a stochastic cooling system

Design of a high-precision fast wire scanner for the SPS at CERN

CERN Document Server

Veness, R; Dehning, B; Emery, J; Herranz Alvarez, J; Koujili, M; Samuelsson, S; Sirvent, J-L

2012-01-01

Studies are going on of a new wire scanner concept. All moving parts are inside the beam vacuum and it is specified for use in all the machines across the CERN accelerator complex. Key components have been developed and tested. Work is now focussing on the installation of a prototype for test in the Super Proton Synchrotron (SPS) accelerator. This article presents the specification of the device and constraints on the design for integration in the different accelerators at CERN. The design issues of the mechanical components are discussed and optimisation work shown. Finally, the prototype design, integrating the several components into the vacuum tank is presented.

A multi-wire beam profile monitor in the AGS

Energy Technology Data Exchange (ETDEWEB)

Huang, H.; Buxton, W.; Castillo, V.; Glenn, J.W. [and others

1997-07-01

A multi-wire beam profile monitor which can be used to directly monitor and control the optical matching between the Booster and AGS rings has been installed and tested in the AGS. Placement of a multi-wire monitor directly in the AGS provides profile measurements taken upon injection and the first two or more revolutions of the beam. The data from such measurements can be used to determine the optical properties of the beam transport line leading into the AGS.

Beam Profile Measurement with Flying Wires at the Fermilab Recycler Ring

CERN Document Server

Hu, Martin; Krider, John; Lorman, Eugene; Marchionni, Alberto; Pishchalnikov, Yu M; Pordes, Stephen; Slimmer, David; Wilson, Peter R; Zagel, James

2005-01-01

The Fermilab Recycler Ring is a high vacuum fixed energy antiproton storage ring with stochastic and electron cooling systems. Flying wires were installed at the Fermilab Recycler Ring for transverse beam profile measurement. The following note describes the system configuration, calibration and resolution of the flying wire system, as well as analysis of the transverse beam profile in the presence of both cooling systems.

First steps towards cube textured nickel profile wires for YBCO-coated conductors

International Nuclear Information System (INIS)

Eickemeyer, J.; Gueth, A.; Freudenberger, J.; Holzapfel, B.; Schultz, L.

2011-01-01

The cube texture as a typical sheet texture can also be formed by cold drawing and recrystallization in profile wires. Cube textured Ni profile wires containing up to 96.2% cube oriented grains in the central region were obtained. Forthcoming investigations are promising to get a textured substrate wire for YBCO-coated conductors. Cube textured nickel alloy tapes prepared by cold rolling and annealing (RABiTS method) represent a standard metallic substrate for superconductor coatings of the YBa 2 Cu 3 O 7-δ (YBCO) type. These tapes have a width to thickness ratio of about 30-100. However, a value of close to one is optimal concerning low energetic losses under alternating current applications. First experiments on micro-alloyed nickel prove that the cube texture as a typical sheet texture can also be formed in profile wires with a rectangular cross-section after cold drawing and recrystallization treatment.

Calculation of the Scattered Radiation Profile in 64 Slice CT Scanners Using Experimental Measurement

Directory of Open Access Journals (Sweden)

Afshin Akbarzadeh

2009-06-01

Full Text Available Introduction: One of the most important parameters in x-ray CT imaging is the noise induced by detected scattered radiation. The detected scattered radiation is completely dependent on the scanner geometry as well as size, shape and material of the scanned object. The magnitude and spatial distribution of the scattered radiation in x-ray CT should be quantified for development of robust scatter correction techniques. Empirical methods based on blocking the primary photons in a small region are not able to extract scatter in all elements of the detector array while the scatter profile is required for a scatter correction procedure. In this study, we measured scatter profiles in 64 slice CT scanners using a new experimental measurement. Material and Methods: To measure the scatter profile, a lead block array was inserted under the collimator and the phantom was exposed at the isocenter. The raw data file, which contained detector array readouts, was transferred to a PC and was read using a dedicated GUI running under MatLab 7.5. The scatter profile was extracted by interpolating the shadowed area. Results: The scatter and SPR profiles were measured. Increasing the tube voltage from 80 to 140 kVp resulted in an 80% fall off in SPR for a water phantom (d=210 mm and 86% for a polypropylene phantom (d = 350 mm. Increasing the air gap to 20.9 cm caused a 30% decrease in SPR. Conclusion: In this study, we presented a novel approach for measurement of scattered radiation distribution and SPR in a CT scanner with 64-slice capability using a lead block array. The method can also be used on other multi-slice CT scanners. The proposed technique can accurately estimate scatter profiles. It is relatively straightforward, easy to use, and can be used for any related measurement.

Estimation and display of beam density profiles

Energy Technology Data Exchange (ETDEWEB)

Dasgupta, S; Mukhopadhyay, T; Roy, A; Mallik, C

1989-03-15

A setup in which wire-scanner-type beam-profile monitor data are collected on-line in a nuclear data-acquisition system has been used and a simple algorithm for estimation and display of the current density distribution in a particle beam is described.

Design and construction of a new actuator for the LHC wire scanner

CERN Document Server

Koujili, Mohamed

The LHC collides two protons beams with an energy of 7 TeV each resultingin a aimed total particle rate of about 109 Hz. The particle rateis determined by the production cross section, a natural constant and theluminosity accelerator dependent parameter describing the particle beams.The luminosity depends on the number of particles in each beam linearlyand on the transverse dimensions of the particle beam inversely. It increaseswith the particle beam density and therefore the probability of interactions.To optimize the transverse beams sizes, pro_le monitors are used to measureparameter depending changes. Within the LHC, three di_erent typesof pro_le monitors are installed: Wire scanner (WS), Synchrotron lightmonitor and Rest Gas Pro_le Monitor. The WS monitor is considered tobe the most accurate of these monitors and serves as a calibration devicefor the two others. The WS is an electro-mechanical device which measuresthe transverse beam density pro_le in an intermittent way. As the wirepasses through the be...

A real-time FPGA based monitoring and fault detection processing system for the Beam Wire Scanner instruments at CERN

CERN Document Server

AUTHOR|(CDS)2070252; Tognolini, Maurizio; Zamantzas, Christos

The CERN Beam Instrumentation group (BE-BI) is designing a new generation of an instrument called Beam Wire Scanner (BWS). This system uses an actuator to move a very thin wire through a particle beams, back and forth with a movement stroke of pi [rad]. To achieve very fast speed when touching the particle beam with such a small stroke, large torque is applied while the expected smoothness of the displacement is crucial. This system relies on a resolver to determine the angular position and power correctly its Permanent Magnet Synchronous Motor (PMSM). In 2016, a failure of the position acquisition chain has highlighted the severe consequences of such problem, which resulted by 24 hours downtime of the Super Proton Synchrotron (SPS) accelerator with significant financial consequences. This work mitigates this single failure point by taking advantage of the existing redundancy in the sensors embedded on the system. The resolver is compared to two Incremental Optical Position Sensor (IOPS) developed in-house ...

Energy Deposition in a Septum Wire

CERN Document Server

Ferioli, G; Knaus, P; Koopman, J; CERN. Geneva. SPS and LHC Division

2001-01-01

The present note describes a machine development (MD) aimed to confirm experimentally the need for protection of the extraction wire septum ZS in SPS long straight section LSS6 during LHC operation. Single wires identical to the ones mounted on the extraction septum were fixed on a fast wire scanner and put into the beam path. The beam heated the wire until it broke after a measured number of turns. The maximum single shot intensity the septum wires could withstand was thus calculated and compared with simulation results.

Computed tomographic reconstruction of beam profiles with a multi-wire chamber

International Nuclear Information System (INIS)

Alonso, J.R.; Tobias, C.A.; Chu, W.T.

1979-03-01

MEDUSA (MEdical Dose Uniformity SAmpler), a 16 plane multi-wire proportional chamber, has been built to accurately measure beam profiles. The large number of planes allows for reconstruction of highly detailed beam intensity structures by means of Fourier convolution reconstruction techniques. This instrument is being used for verification and tuning of the Bevalac radiotherapy beams, but has potential applications in many beam profile monitoring situations

Mission-profile-based stress analysis of bond-wires in SiC power modules

DEFF Research Database (Denmark)

Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede

2016-01-01

This paper proposes a novel mission-profile-based reliability analysis approach for stress on bond wires in Silicon Carbide (SiC) MOSFET power modules using statistics and thermo-mechanical FEM analysis. In the proposed approach, both the operational and environmental thermal stresses are taken...... into account. The approach uses a two-dimension statistical analysis of the operating conditions in a real one-year mission profile sampled at time frames 5 minutes long. For every statistical bin corresponding to a given operating condition, the junction temperature evolution is estimated by a thermal network...... and the mechanical stress on bond wires is consequently extracted by finite-element simulations. In the final step, the considered mission profile is translated in a stress sequence to be used for Rainflow counting calculation and lifetime estimation....

A feasibility study of Dynamic Phantom scanner for quality assurance of photon beam profiles at various gantry angles.

Science.gov (United States)

Zhang, Yunkai; Hsi, Wen C; Chu, James C H; Bernard, Damian B; Abrams, Ross A

2005-01-01

The effect of gantry rotation on beam profiles of photon and electron beams is an important issue in quality assurance for radiotherapy. To address variations in the profiles of photon and electron beams at different gantry angles, a Dynamic Phantom scanner composed of a 20 x 12 x 6 cm3 scanning Lucite block was designed as a cross-beam-profile scanner. To our knowledge, differences between scanned profiles acquired at different gantry angles with a small size Lucite block and those acquired a full-size (60 x 60 x 50 cm3) water phantom have not been previously investigated. We therefore performed a feasibility study for a first prototype Dynamic Phantom scanner without a gantry attachment mount. Radiation beams from a Varian LINAC 21EX and 2100C were used. Photon beams (6 MV and 18 MV) were shaped by either collimator jaws or a Varian 120 Multileaf (MLC) collimator, and electron beams (6 MeV, 12 MeV, and 20 MeV) were shaped by a treatment cone. To investigate the effect on profiles by using a Lucite block, a quantitative comparison of scanned profiles with the Dynamic Phantom and a full-size water phantom was first performed at a 0 degrees gantry angle for both photon and electron beams. For photon beam profiles defined by jaws at 1.0 cm and 5.0 cm depths of Lucite (i.e., at 1.1 cm and 5.7 cm depth of water), a good agreement (less than 1% variation) inside the field edge was observed between profiles scanned with the Dynamic Phantom and with a water phantom. The use of Lucite in the Dynamic Phantom resulted in reduced penumbra width (about 0.5 mm out of 5 mm to 8mm) and reduced (1% to 2%) scatter dose beyond the field edges for both 6 MV and 18 MV beams, compared with the water phantom scanner. For profiles of the MLC-shaped 6 MV photon beam, a similar agreement was observed. For profiles of electron beams scanned at 2.9 cm depth of Lucite (i.e., at 3.3 cm depth of water), larger disagreements in profiles (3% to 4%) and penumbra width (3 mm to 4 mm out of 12 mm

Recent micro-CT scanner developments at UGCT

Energy Technology Data Exchange (ETDEWEB)

Dierick, Manuel, E-mail: Manuel.Dierick@UGent.be [UGCT-Department of Physics and Astronomy, Faculty of Sciences, Ghent University, Proeftuinstraat 86, 9000 Ghent (Belgium); XRE, X-Ray Engineering bvba, De Pintelaan 111, 9000 Ghent (Belgium); Van Loo, Denis, E-mail: info@XRE.be [XRE, X-Ray Engineering bvba, De Pintelaan 111, 9000 Ghent (Belgium); Masschaele, Bert [UGCT-Department of Physics and Astronomy, Faculty of Sciences, Ghent University, Proeftuinstraat 86, 9000 Ghent (Belgium); XRE, X-Ray Engineering bvba, De Pintelaan 111, 9000 Ghent (Belgium); Van den Bulcke, Jan [UGCT-Woodlab-UGent, Department of Forest and Water Management, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent (Belgium); Van Acker, Joris, E-mail: Joris.VanAcker@UGent.be [UGCT-Woodlab-UGent, Department of Forest and Water Management, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent (Belgium); Cnudde, Veerle, E-mail: Veerle.Cnudde@UGent.be [UGCT-SGIG, Department of Geology and Soil Science, Faculty of Sciences, Ghent University, Krijgslaan 281, S8, 9000 Ghent (Belgium); Van Hoorebeke, Luc, E-mail: Luc.VanHoorebeke@UGent.be [UGCT-Department of Physics and Astronomy, Faculty of Sciences, Ghent University, Proeftuinstraat 86, 9000 Ghent (Belgium)

2014-04-01

This paper describes two X-ray micro-CT scanners which were recently developed to extend the experimental possibilities of microtomography research at the Centre for X-ray Tomography ( (www.ugct.ugent.be)) of the Ghent University (Belgium). The first scanner, called Nanowood, is a wide-range CT scanner with two X-ray sources (160 kV{sub max}) and two detectors, resolving features down to 0.4 μm in small samples, but allowing samples up to 35 cm to be scanned. This is a sample size range of 3 orders of magnitude, making this scanner well suited for imaging multi-scale materials such as wood, stone, etc. Besides the traditional cone-beam acquisition, Nanowood supports helical acquisition, and it can generate images with significant phase-contrast contributions. The second scanner, known as the Environmental micro-CT scanner (EMCT), is a gantry based micro-CT scanner with variable magnification for scanning objects which are not easy to rotate in a standard micro-CT scanner, for example because they are physically connected to external experimental hardware such as sensor wiring, tubing or others. This scanner resolves 5 μm features, covers a field-of-view of about 12 cm wide with an 80 cm vertical travel range. Both scanners will be extensively described and characterized, and their potential will be demonstrated with some key application results.

Recent micro-CT scanner developments at UGCT

International Nuclear Information System (INIS)

Dierick, Manuel; Van Loo, Denis; Masschaele, Bert; Van den Bulcke, Jan; Van Acker, Joris; Cnudde, Veerle; Van Hoorebeke, Luc

2014-01-01

This paper describes two X-ray micro-CT scanners which were recently developed to extend the experimental possibilities of microtomography research at the Centre for X-ray Tomography ( (www.ugct.ugent.be)) of the Ghent University (Belgium). The first scanner, called Nanowood, is a wide-range CT scanner with two X-ray sources (160 kV max ) and two detectors, resolving features down to 0.4 μm in small samples, but allowing samples up to 35 cm to be scanned. This is a sample size range of 3 orders of magnitude, making this scanner well suited for imaging multi-scale materials such as wood, stone, etc. Besides the traditional cone-beam acquisition, Nanowood supports helical acquisition, and it can generate images with significant phase-contrast contributions. The second scanner, known as the Environmental micro-CT scanner (EMCT), is a gantry based micro-CT scanner with variable magnification for scanning objects which are not easy to rotate in a standard micro-CT scanner, for example because they are physically connected to external experimental hardware such as sensor wiring, tubing or others. This scanner resolves 5 μm features, covers a field-of-view of about 12 cm wide with an 80 cm vertical travel range. Both scanners will be extensively described and characterized, and their potential will be demonstrated with some key application results

A feasibility study of the Dynamic Phantom scanner for quality assurance of beam profiles at various gantry angles

Science.gov (United States)

Zhang, Yunkai; Hsi, Wen C.; Chu, James C.H.; Bernard, Damian B.; Abrams, Ross A.

2005-01-01

The effect of gantry rotation on beam profiles of photon and electron beams is an important issue in quality assurance for radiotherapy. To address variations in the profiles of photon and electron beams at different gantry angles, a Dynamic Phantom scanner composed of a 20×12×6 cm3 scanning Lucite block was designed as a cross‐beam‐profile scanner. To our knowledge, differences between scanned profiles acquired at different gantry angles with a small size Lucite block and those acquired a full‐size (60×60×50 cm3) water phantom have not been previously investigated. We therefore performed a feasibility study for a first prototype Dynamic Phantom scanner without a gantry attachment mount. Radiation beams from a Varian LINAC 21EX and 2100C were used. Photon beams (6 MV and 18 MV) were shaped by either collimator jaws or a Varian 120 Multileaf (MLC) collimator, and electron beams (6 MeV, 12 MeV, and 20 MeV) were shaped by a treatment cone. To investigate the effect on profiles by using a Lucite block, a quantitative comparison of scanned profiles with the Dynamic Phantom and a full‐size water phantom was first performed at a 0° gantry angle for both photon and electron beams. For photon beam profiles defined by jaws at 1.0 cm and 5.0 cm depths of Lucite (i.e., at 1.1 cm and 5.7 cm depth of water), a good agreement (less than 1% variation) inside the field edge was observed between profiles scanned with the Dynamic Phantom and with a water phantom. The use of Lucite in the Dynamic Phantom resulted in reduced penumbra width (about 0.5 mm out of 5 mm to 8 mm) and reduced (1% to 2%) scatter dose beyond the field edges for both 6 MV and 18 MV beams, compared with the water phantom scanner. For profiles of the MLC‐shaped 6 MV photon beam, a similar agreement was observed. For profiles of electron beams scanned at 2.9 cm depth of Lucite (i.e., at 3.3 cm depth of water), larger disagreements in profiles (3% to 4%) and penumbra width (3 mm to 4 mm out of 12 mm

Whole-body profile scanner for in vivo quantitative activity measurement

International Nuclear Information System (INIS)

Bergmann, H.

1978-01-01

A whole-body profile scanner has been developed by fitting parallel slit collimators to a shadow shield whole-body counter. Sensitivity, uniformity and resolution measurements were performed using a number of different counting conditions. It is shown that improved accuracy of activity measurements is obtained by using a wide window counting technique for low and medium energy gamma emitters (99m Tc, 131 I), whereas a photopeak window should be used for high energy gamma emitters (47 Ca). Due to the finite spatial resolution of the system a systematic error in evaluating regional activities from the counting rate profile occurs which is characterized by a spatial spillover factor. The spatial spillover factor is measured and is subsequently used to calculate the error on basis of a simple model. It is shown that only small errors are caused by spatial spillover when the length of a region is at least three times the full width half maximum of the point spread function. Applying the above mentioned simple rules it is concluded that profile scanning is a sensitive and accurate technique for activity measurements in vivo. Two examples of clinical applications (measurement of bone accretion rates of calcium and Tc-pyrophosphate, regional radioiodine retention in patients with thyroid carcinoma) and a review of the papers on profile scanning demonstrate the types of investigations in which profile scanning is superior to alternative techniques. (author)

UV laser beam profile measurement by means of the photoelectric effect on the wires of a proportional chamber

International Nuclear Information System (INIS)

Prokoviev, O.; Seiler, P.G.

1989-01-01

A simple technique to measure the profiles of pulsed UV laser beams is described. Irradiating a cathode wire of a proportional chamber with UV laser shots results in signals from the anode wire whose amplitudes are proportional to the UV light intensity. Profile scanning is performed by shifting the chamber across the beam. The chamber can also be used with reversed polarities. This leads to avalanches developing outwardly from the signal wire. In this case we observe a quadratic dependence of the pulse height on the UV light intensity. (orig.)

High intensity beam profile monitors for the LAMPF primary beam lines

International Nuclear Information System (INIS)

Hoffman, E.W.; Macek, R.J.; van Dyck, O.; Lee, D.; Harvey, A.; Bridge, J.; Cainet, J.

1979-01-01

Two types of beam profile monitors are in use at LAMPF to measure the properties of the 800 MeV, 500 μA proton beam external to the linac. Both types use secondary electron emission from a wire to produce a current signal proportional to the amount of proton beam that intercepts the wire. The wire scanner system uses a pair of orthogonal wires which are passed through the beam and the harp system uses two fixed planes of parallel wires. Most of the harps are not retractable and are exposed continuously to the primary beam. The high beam intensities available lead to a number of technical problems for instruments that intercept the beam or are close to primary beam targets. The thermal, electrical, radiation-damage, and material selection problems encountered, and some solutions which have been implemented are discussed

PRODUCTION OF WIRE RML OF SQUARE PROFILE IN CONDITIONS OF BELORUSSIAN METALLURGICAL WORKS

Directory of Open Access Journals (Sweden)

D. G. Sachava

2010-01-01

Full Text Available It is shown that at using of profile (square wire RML in conditions of RUP «BMZ» for production of pipes of high pressure their production is cheapened, what attracts interest of consumer.

The utilization of electronic computers for bone density measurements with iodine 125 profile scanner

International Nuclear Information System (INIS)

Reiners, C.

1974-01-01

The utilization of electronic computers in the determination of the mineral content in bone with the 125 I profile scanner offers many advantages. The computer considerably lessens intensive work of routine evaluation. It enables the direct calculation of the attenuation coefficients. This means a greater accuracy and correctness of the results compared to the former 'graphical' method, as the approximations are eliminated and reference errors are avoided. (orig./LH) [de

Beam profile monitors for a tagged photon beam facility

International Nuclear Information System (INIS)

Arends, J.; Breuer, M.; Dahmen, H.D.; Detemple, P.; Schneider, W.; Urban, D.; Zucht, B.

1991-01-01

A beam profile monitor for electron and photon beams is described, which operates at the low intensities encountered in a tagged bremsstrahlung beam environment, typically 10 10 electrons/s and 10 7 photons/s. The method is based on a wire scanner and utilizes the presence of a tagging spectrometer. The accuracy of the measurements can be tuned in a wide range to meet the requirements set by the actual beam parameters. Examples of measured electron and photon beam profiles at the tagged photon beam of the PHOENICS experiment at the electron stretcher ring ELSA in Bonn are given. (orig.)

A beam profile monitor for a tagged photon beam

International Nuclear Information System (INIS)

Arends, J.; Breuer, M.; Dahmen, H.D.; Detemple, P.; Noeldeke, G.; Schneider, W.; Zucht, B.

1990-10-01

A beam profile monitor for electron and photon beams is described, which operates at the low intensities encountered in a tagged bremsstrahlung beam environment, typically 10 10 electrons/s and 10 7 photons/s. The method is based on a wire scanner and utilizes the presence of a tagging spectrometer. The accuracy of the measurements can be tuned in a wide range (at the expense of measuring time) to meet the requirements set by the actual beam size. Examples of measured electron and photon beam profiles at the tagged photon beam of the PHOENICS experiment at the electron stretcher ring ELSA are given. (orig.)

A beam profile monitor for a tagged photon beam

Energy Technology Data Exchange (ETDEWEB)

Arends, J.; Breuer, M.; Dahmen, H.D.; Detemple, P.; Noeldeke, G.; Schneider, W.; Zucht, B.

1990-10-01

A beam profile monitor for electron and photon beams is described, which operates at the low intensities encountered in a tagged bremsstrahlung beam environment, typically 10{sup 10} electrons/s and 10{sup 7} photons/s. The method is based on a wire scanner and utilizes the presence of a tagging spectrometer. The accuracy of the measurements can be tuned in a wide range (at the expense of measuring time) to meet the requirements set by the actual beam size. Examples of measured electron and photon beam profiles at the tagged photon beam of the PHOENICS experiment at the electron stretcher ring ELSA are given. (orig.).

Measurement of position and profile of undulator radiation in Indus-2 using scanning wire monitor

International Nuclear Information System (INIS)

Kant, Chander; Lal, Sohan; Raghuwanshi, V.K.; Prasad, Vijendra

2015-01-01

Two planar undulators (U1 and U2) for Atomic Molecular Spectroscopy (AMOS) beamline and Angle Resolved Photoelectron Spectroscopy (ARPES) beamline have been installed in Indus-2. The U1 undulator is designed to produce photons in the energy range of 6 eV to 250 eV and U2 undulator is designed to produce photons in the energy range of 30 eV to 600 eV. In order to measure the position and vertical profile of photon beams emitted from these undulators, one scanning wire monitor has been installed in each beamline front end. In these scanning wire monitors, a gold coated tungsten wire of 100 μm thickness, stretched between a fork shaped alumina ceramic holder, is scanned vertically perpendicular to the direction of propagation of photon beam by using a precisely controlled stepper motor. The photo-electron current generated in the wire is measured by an electrometer. A graphical user interface has been developed which facilitates the scanning as per the given range, plots the graphs and stores the scanned data in Excel file. This paper describes our experience and usefulness of these wire monitors during commissioning of planar undulators in Indus-2. (author)

Metal release profiles of orthodontic bands, brackets, and wires: an in vitro study.

Science.gov (United States)

Wendl, B; Wiltsche, H; Lankmayr, E; Winsauer, H; Walter, A; Muchitsch, A; Jakse, N; Wendl, M; Wendl, T

2017-11-01

The present study evaluated the temporal release of Co Cr, Mn, and Ni from the components of a typical orthodontic appliance during simulated orthodontic treatment. Several commercially available types of bands, brackets, and wires were exposed to an artificial saliva solution for at least 44 days and the metals released were quantified in regular intervals using inductively coupled plasma quadrupole mass spectrometry (ICP-MS, Elan DRC+, Perkin Elmer, USA). Corrosion products encountered on some products were investigated by a scanning electron microscope equipped with an energy dispersive X-ray microanalyzer (EDX). Bands released the largest quantities of Co, Cr, Mn, and Ni, followed by brackets and wires. Three different temporal metal release profiles were observed: (1) constant, though not necessarily linear release, (2) saturation (metal release stopped after a certain time), and (3) an intermediate release profile that showed signs of saturation without reaching saturation. These temporal metal liberation profiles were found to be strongly dependent on the individual test pieces. The corrosion products which developed on some of the bands after a 6-month immersion in artificial saliva and the different metal release profiles of the investigated bands were traced back to different attachments welded onto the bands. The use of constant release rates will clearly underestimate metal intake by the patient during the first couple of days and overestimate exposure during the remainder of the treatment which is usually several months long. While our data are consistent with heavy metal release by orthodontic materials at levels well below typical dietary intake, we nevertheless recommend the use of titanium brackets and replacement of the band with a tube in cases of severe Ni or Cr allergy.

Compression dynamics of quasi-spherical wire arrays with different linear mass profiles

International Nuclear Information System (INIS)

Mitrofanov, K. N.; Aleksandrov, V. V.; Gritsuk, A. N.; Grabovski, E. V.; Frolov, I. N.; Laukhin, Ya. N.; Oleinik, G. M.; Ol’khovskaya, O. G.

2016-01-01

Results of experimental studies of the implosion of quasi-spherical wire (or metalized fiber) arrays are presented. The goal of the experiments was to achieve synchronous three-dimensional compression of the plasma produced in different regions of a quasi-spherical array into its geometrical center. To search for optimal synchronization conditions, quasi-spherical arrays with different initial profiles of the linear mass were used. The following dependences of the linear mass on the poloidal angle were used: m_l(θ) ∝ sin"–"1θ and m_l(θ) ∝ sin"–"2θ. The compression dynamics of such arrays was compared with that of quasi-spherical arrays without linear mass profiling, m_l(θ) = const. To verify the experimental data, the spatiotemporal dynamics of plasma compression in quasi-spherical arrays was studied using various diagnostics. The experiments on three-dimensional implosion of quasi-spherical arrays made it possible to study how the frozen-in magnetic field of the discharge current penetrates into the array. By measuring the magnetic field in the plasma of a quasi-spherical array, information is obtained on the processes of plasma production and formation of plasma flows from the wire/fiber regions with and without an additionally deposited mass. It is found that penetration of the magnetic flux depends on the initial linear mass profile m_l(θ) of the quasi-spherical array. From space-resolved spectral measurements and frame imaging of plasma X-ray emission, information is obtained on the dimensions and shape of the X-ray source formed during the implosion of a quasi-spherical array. The intensity of this source is estimated and compared with that of the Z-pinch formed during the implosion of a cylindrical array.

Beam Profile Measurement of 300 kV Ion Source Test Stand for 1 MV Electrostatic Accelerator

International Nuclear Information System (INIS)

Park, Sae-Hoon; Kim, Yu-Seok; Kim, Dae-Il; Kwon, Hyeok-Jung; Cho, Yong-Sub

2015-01-01

In this paper, RF ion source, test stand of the ion source and its test results are presented. Beam profile was measured at the downstream from the accelerating tube and at the beam dump by using BPM and wire scanner. The RF ion source of the test stand is verified by measuring the total beam current with a faraday cup in the chamber. The KOMAC (KOrea Multi-purpose Accelerator Complex) has been developing a 300 kV ion source test stand for a 1 MV electrostatic accelerator. An ion source and accelerating tube will be installed in a high pressure vessel. The ion source in a high pressure vessel requires high reliability. To confirm the stable operation of the ion source, a test stand was proposed and developed. The ion source will be tested at the test stand to verify its long-term operation conditions. The test stand consists of a 300 kV high voltage terminal, a battery for the ion source power, a 60 Hz inverter, a 200 MHz RF power, a 5 kV extraction power supply, a 300 kV accelerating tube, and a vacuum system. The beam profile monitor was installed at the downstream from the accelerating tube. Wire scanner and faraday-cup was installed at the end of the chamber

Beam Profile Measurement of 300 kV Ion Source Test Stand for 1 MV Electrostatic Accelerator

Energy Technology Data Exchange (ETDEWEB)

Park, Sae-Hoon; Kim, Yu-Seok [Dongguk University, Gyeonju (Korea, Republic of); Kim, Dae-Il; Kwon, Hyeok-Jung; Cho, Yong-Sub [Korea Multipurpose Accelerator Complex, Gyeongju (Korea, Republic of)

2015-10-15

In this paper, RF ion source, test stand of the ion source and its test results are presented. Beam profile was measured at the downstream from the accelerating tube and at the beam dump by using BPM and wire scanner. The RF ion source of the test stand is verified by measuring the total beam current with a faraday cup in the chamber. The KOMAC (KOrea Multi-purpose Accelerator Complex) has been developing a 300 kV ion source test stand for a 1 MV electrostatic accelerator. An ion source and accelerating tube will be installed in a high pressure vessel. The ion source in a high pressure vessel requires high reliability. To confirm the stable operation of the ion source, a test stand was proposed and developed. The ion source will be tested at the test stand to verify its long-term operation conditions. The test stand consists of a 300 kV high voltage terminal, a battery for the ion source power, a 60 Hz inverter, a 200 MHz RF power, a 5 kV extraction power supply, a 300 kV accelerating tube, and a vacuum system. The beam profile monitor was installed at the downstream from the accelerating tube. Wire scanner and faraday-cup was installed at the end of the chamber.

The effect of electrostatic and gravity force on offset wire inside tube

Science.gov (United States)

Oh, S. H.; Hazineh, D.; Wang, C.

2018-04-01

In a straw-tube detector, a wire that is offset with respect to the tube axis experiences a Coulomb force when high voltage is applied between the anode wire and the tube. This force results in a shifting of the wire and straw, in addition to the gravitational sag, and is a function of the tube and wire radius, initial offset, high voltage, tension and length. The presence of such effects is well known, but the precise magnitude of the shift for the anode wires under conditions of detector operation have not been previously documented with measurable confidence. In this work, we provide the first systematic measurements for the wire shift in straw-tube detectors due to gravity and the electrostatic force using an x-ray scanner developed for the Mu2e experiment. The data are compared to the solutions of the differential equations governing the system, and we find a good match between the two. The solutions can predict the final wire and straw positions from the initial positions measured without the high voltage, and the final wire and straw positions can then be used as an input to the track reconstruction software to improve the track position resolution.

Comparative evaluation of ultrasound scanner accuracy in distance measurement

Science.gov (United States)

Branca, F. P.; Sciuto, S. A.; Scorza, A.

2012-10-01

The aim of the present study is to develop and compare two different automatic methods for accuracy evaluation in ultrasound phantom measurements on B-mode images: both of them give as a result the relative error e between measured distances, performed by 14 brand new ultrasound medical scanners, and nominal distances, among nylon wires embedded in a reference test object. The first method is based on a least squares estimation, while the second one applies the mean value of the same distance evaluated at different locations in ultrasound image (same distance method). Results for both of them are proposed and explained.

Overview of laserwire beam profile and emittance measurements for high power proton accelerators

CERN Document Server

Gibson, S M; Bosco, A; Gabor, C; Pozimski, J; Savage, P; Hofmann, T

2013-01-01

Laserwires were originally developed to measure micron-sized electron beams via Compton scattering, where traditional wire scanners are at the limit of their resolution. Laserwires have since been applied to larger beamsize, high power H$^-$ ion beams, where the non-invasive method can probe beam densities that would damage traditional diagnostics. While photo-detachment of H$^-$ ions is now routine to measure beam profiles, extending the technique to transverse and longitudinal emittance measurements is a key aim of the laserwire emittance scanner under construction at the Front End Test Stand (FETS) at the RAL. A pulsed, 30 kHz, 8kW peak power laser is fibrecoupled to motorized collimating optics, which controls the position and thickness of the laserwire delivered to the H- interaction chamber. The laserwire slices out a beamlet of neutralized particles, which propagate to a downstream scintillator and camera. The emittance is reconstructed from 2D images as the laserwire position is scanned. Results from ...

Status and test report on the LANL-Boeing APLE/HPO flying-wire beam-profile monitor. Status report

Energy Technology Data Exchange (ETDEWEB)

Wilke, M.; Barlow, D.; Fortgang, C.; Gilpatrick, J.; Meyer, R.; Rendon, A.; Warren, D. [Los Alamos National Lab., NM (United States); Greegor, R. [Boeing Co., Seattle, WA (United States)

1994-07-01

The High-Power Oscillator (HPO) demonstration of the Average Power Laser Experiment (APLE) is a collaboration by Los Alamos National Laboratory and Boeing to demonstrate a 10 kW average power, 10 {mu}m free electron laser (FEL). As part of the collaboration, Los Alamos National Laboratory (LANL) is responsible for many of the electron beam diagnostics in the linac, transport, and laser sections. Because of the high duty factor and power of the electron beam, special diagnostics are required. This report describes the flying wire diagnostic required to monitor the beam profile during high-power, high-duty operation. The authors describe the diagnostic and prototype tests on the Los Alamos APLE Prototype Experiment (APEX) FEL. They also describe the current status of the flying wires being built for APLE.

A 3D airborne ultrasound scanner

Science.gov (United States)

Capineri, L.; Masotti, L.; Rocchi, S.

1998-06-01

This work investigates the feasibility of an ultrasound scanner designed to reconstruct three-dimensional profiles of objects in air. There are many industrial applications in which it is important to obtain quickly and accurately the digital reconstruction of solid objects with contactless methods. The final aim of this project was the profile reconstruction of shoe lasts in order to eliminate the mechanical tracers from the reproduction process of shoe prototypes. The feasibility of an ultrasonic scanner was investigated in laboratory conditions on wooden test objects with axial symmetry. A bistatic system based on five airborne polyvinylidenedifluoride (PVDF) transducers was mechanically moved to emulate a cylindrical array transducer that can host objects of maximum width and height 20 cm and 40 cm respectively. The object reconstruction was based on a simplified version of the synthetic aperture focusing technique (SAFT): the time of flight (TOF) of the first in time echo for each receiving transducer was taken into account, a coarse spatial sampling of the ultrasonic field reflected on the array transducer was delivered and the reconstruction algorithm was based on the ellipsoidal backprojection. Measurements on a wooden cone section provided submillimetre accuracy in a controlled environment.

Influence of the profile of Iridium-192 wire in measurements of quality control for use in brachytherapy

International Nuclear Information System (INIS)

Costa, Osvaldo L.; Zeituni, Carlos A.; Rostelato, Maria Elisa C.M.; Moura, Joao A.; Feher, Anselmo; Moura, Eduardo S.; Souza, Carla D.; Somessari, Samir L.; Peleias Junior, Fernando S.; Mattos, Fabio R.

2013-01-01

Brachytherapy is a method used in the treatment of cancerous tumors, by ionizing radiation produced by sources, introduced into the tumor area, this method seeks a more direct to the tumor, thereby maximizing the radiation dose to diseased tissue, while minimizing the dose to healthy tissues. One of the radionuclides used in brachytherapy is iridium-192. The Radiation Technology Center (CTR), of the Nuclear and Energy Research Institute (IPEN), has produced commercially, since 1998, iridium-192 wires used in low dose rate (LDR) brachytherapy. To produce this radionuclides, firstly an iridium-platinum wire is irradiated in the nuclear reactor IEA-R1 for 30 hours, with a neutron flux of 5x 10 13 n cm -2 s -1 , the wire is left to decay by 30 days to remove the main contaminants, and then goes through a quality control, before being sent to the hospital. In this quality control is checked the radiation homogeneity along each centimeter of the wire. To implement this procedure, is used a device, consisting of an ionization chamber, surrounded by a lead shield, with a samol 1 cm wide slit, linked to the ionization chamber is a voltage source, and a Keithley 617 electrometer, 2 minutes is the range used to measure the charge by the electrometer. The iridium wire is considered in accordance, when there is no variation higher than 5%, between the average measures and the maximum and minimum values. However, due to design features of the measurement system, the wire may appear to the detector through the slit in larger sizes than the ideal, improperly influencing the final quality control. This paper calculates the difference in size of these variations in profile, and their influence on the final count, it compares the actual values obtained, and describes the improvements, made in quality control procedures, that provided more accurate measurement data, analyzes the results, and suggests changes in devices, aimed at further improving the quality control of iridium-192

A Flying Wire System in the AGS

International Nuclear Information System (INIS)

Huang, H.; Buxton, W.; Mahler, G.; Marusic, A.; Roser, T.; Smith, G.; Syphers, M.; Williams, N.; Witkover, R.

1999-01-01

As the AGS prepares to serve as the injector for RHIC, monitoring and control of the beam transverse emittance become a major and important topic. Before the installation of the flying wire system, the emittance was measured with ionization profile monitors in the AGS, which require correction for space charge effects. It is desirable to have a second means of measuring profile that is less dependent on intensity. A flying wire system has been installed in the AGS recently to perform this task. This paper discusses the hardware and software setup and the capabilities of the system

Interferometer for electron density measurement in exploding wire plasma

International Nuclear Information System (INIS)

Batra, Jigyasa; Jaiswar, Ashutosh; Kaushik, T.C.

2016-12-01

Mach-Zehnder Interferometer (MZI) has been developed for measuring electron density profile in pulsed plasmas. MZI is to be used for characterizing exploding wire plasmas for correlating electron density dynamics with x-rays emission. Experiments have been carried out for probing electron density in pulsed plasmas produced in our laboratory like in spark gap and exploding wire plasmas. These are microsecond phenomenon. Changes in electron density have been registered in interferograms with the help of a streak camera for specific time window. Temporal electron density profiles have been calculated by analyzing temporal fringe shifts in interferograms. This report deals with details of MZI developed in our laboratory along with its theory. Basic introductory details have also been provided for exploding wire plasmas to be probed. Some demonstrative results of electron density measurements in pulsed plasmas of spark gap and single exploding wires have been described. (author)

Side scanner for supermarkets: a new scanner design standard

Science.gov (United States)

Cheng, Charles K.; Cheng, J. K.

1996-09-01

High speed UPC bar code has become a standard mode of data capture for supermarkets in the US, Europe, and Japan. The influence of the ergonomics community on the design of the scanner is evident. During the past decade the ergonomic issues of cashier in check-outs has led to occupational hand-wrist cumulative trauma disorders, in most cases causing carpal tunnel syndrome, a permanent hand injury. In this paper, the design of a side scanner to resolve the issues is discussed. The complex optical module and the sensor for aforesaid side scanner is described. The ergonomic advantages offer the old counter mounted vertical scanner has been experimentally proved by the industrial funded study at an independent university.

Important considerations for radiochromic film dosimetry with flatbed CCD scanners and EBT GAFCHROMIC[reg] film

International Nuclear Information System (INIS)

Lynch, Bart D.; Kozelka, Jakub; Ranade, Manisha K.; Li, Jonathan G.; Simon, William E.; Dempsey, James F.

2006-01-01

In this study, we present three significant artifacts that have the potential to negatively impact the accuracy and precision of film dosimetry measurements made using GAFCHROMIC[reg] EBT radiochromic film when read out with CCD flatbed scanners. Films were scanned using three commonly employed instruments: a Macbeth TD932 spot densitometer, an Epson Expression 1680 CCD array scanner, and a Microtek ScanMaker i900 CCD array scanner. For the two scanners we assessed the variation in optical density (OD) of GAFCHROMIC EBT film with scanning bed position, angular rotation of the film with respect to the scan line direction, and temperature inside the scanner due to repeated scanning. Scanning uniform radiochromic films demonstrated a distinct bowing effect in profiles in the direction of the CCD array with a nonuniformity of up to 17%. Profiles along a direction orthogonal to the CCD array demonstrated a 7% variation. A strong angular dependence was found in measurements made with the flatbed scanners; the effect could not be reproduced with the spot densitometer. An IMRT quality assurance film was scanned twice rotating the film 90 deg. between the scans. For films scanned on the Epson scanner, up to 12% variation was observed in unirradiated EBT films rotated between 0 deg. and 90 deg. , which decreased to approximately 8% for EBT films irradiated to 300 cGy. Variations of up to 80% were observed for films scanned with the Microtek scanner. The scanners were found to significantly increase the film temperature with repeated scanning. Film temperature between 18 and 33 deg. C caused OD changes of approximately 7%. Considering these effects, we recommend adherence to a strict scanning protocol that includes: maintaining the orientation of films scanned on flatbed scanners, limiting scanning to the central portion of the scanner bed, and limiting the number of consecutive scans to minimize changes in OD caused by film heating

Test Measurements of a 20 ms-1 Carbon Wire Beam Scanner

CERN Document Server

De Freitas, J; Emery, J; Herranz Alvarez, J F; Koujili, M; Ramos, D; Sapinski, M; Ait-Amira, Y; Djerdir, A

2011-01-01

This paper pre­sents the de­sign of the ac­tu­a­tor for the fast and high ac­cu­ra­cy Wire Scan­ner sys­tem. The ac­tu­a­tor con­sists of a ro­tary brushless syn­chronous motor with the per­ma­nent mag­net rotor in­stalled in­side the vac­u­um cham­ber and the sta­tor in­stalled out­side. The fork, per­ma­nent mag­net rotor and two an­gu­lar po­si­tion sen­sors are mount­ed on the same axis and lo­cat­ed in­side the beam vac­u­um cham­ber. The system has to re­sist a bake-out tem­per­a­ture of 200 C and ion­iz­ing radi­a­tion up to tenths of kGy/year. Max­i­mum wire trav­el­ling speed of 20 m/s and a po­si­tion mea­sure­ment ac­cu­ra­cy of 4 um is re­quired. Therefore, the sys­tem must avoid gen­er­at­ing vi­bra­tion and electromagnet­ic in­ter­fer­ence. A dig­i­tal feed­back con­troller will allow max­i­mum flex­i­bil­i­ty for the loop pa­ram­e­ters and feeds the 3-phase lin­ear power driv­er. The per­for­mance of the pr...

Self-organization of mesoscopic silver wires by electrochemical deposition

Directory of Open Access Journals (Sweden)

Sheng Zhong

2014-08-01

Full Text Available Long, straight mesoscale silver wires have been fabricated from AgNO3 electrolyte via electrodeposition without the help of templates, additives, and surfactants. Although the wire growth speed is very fast due to growth under non-equilibrium conditions, the wire morphology is regular and uniform in diameter. Structural studies reveal that the wires are single-crystalline, with the [112] direction as the growth direction. A possible growth mechanism is suggested. Auger depth profile measurements show that the wires are stable against oxidation under ambient conditions. This unique system provides a convenient way for the study of self-organization in electrochemical environments as well as for the fabrication of highly-ordered, single-crystalline metal nanowires.

A New Flying Wire System for the Tevatron

Science.gov (United States)

Blokland, Willem; Dey, Joseph; Vogel, Greg

1997-05-01

A new Flying Wires system replaces the old system to enhance the analysis of the beam emittance, improve the reliability, and handle the upcoming upgrades of the Tevatron. New VME data acquisition modules and timing modules allow for more bunches to be sampled more precisely. The programming language LabVIEW, running on a Macintosh computer, controls the VME modules and the nuLogic motion board that flies the wires. LabVIEW also analyzes and stores the data, and handles local and remote commands. The new system flies three wires and fits profiles of 72 bunches to a gaussian function within two seconds. A new console application operates the flying wires from any control console. This paper discusses the hardware and software setup, the capabilities and measurement results of the new Flying Wires system.

Multifilament Cable Wire versus Conventional Wire for Sternal Closure in Patients Undergoing Major Cardiac Surgery

Directory of Open Access Journals (Sweden)

You Na Oh

2015-08-01

Full Text Available Background: Stainless steel wiring remains the most popular technique for primary sternal closure. Recently, a multifilament cable wiring system (Pioneer Surgical Technology Inc., Marquette, MI, USA was introduced for sternal closure and has gained wide acceptance due to its superior resistance to tension. We aimed to compare conventional steel wiring to multifilament cable fixation for sternal closure in patients undergoing major cardiac surgery. Methods: Data were collected retrospectively on 1,354 patients who underwent sternal closure after major cardiac surgery, using either the multifilament cable wiring system or conventional steel wires between January 2009 and October 2010. The surgical outcomes of these two groups of patients were compared using propensity score matching based on 18 baseline patient characteristics. Results: Propensity score matching yielded 392 pairs of patients in the two groups whose baseline profiles showed no significant differences. No significant differences between the two groups were observed in the rates of early mortality (2.0% vs. 1.3%, p=0.578, major wound complications requiring reconstruction (1.3% vs. 1.3%, p＞0.99, minor wound complications (3.6% vs. 2.0%, p=0.279, or mediastinitis (0.8% vs. 1.0%, p=1.00. Patients in the multifilament cable group had fewer sternal bleeding events than those in the conventional wire group, but this tendency was not statistically significant (4.3% vs. 7.4%, p=0.068. Conclusion: The surgical outcomes of sternal closure using multifilament cable wires were comparable to those observed when conventional steel wires were used. Therefore, the multifilament cable wiring system may be considered a viable option for sternal closure in patients undergoing major cardiac surgery.

Multifilament Cable Wire versus Conventional Wire for Sternal Closure in Patients Undergoing Major Cardiac Surgery.

Science.gov (United States)

Oh, You Na; Ha, Keong Jun; Kim, Joon Bum; Jung, Sung-Ho; Choo, Suk Jung; Chung, Cheol Hyun; Lee, Jae Won

2015-08-01

Stainless steel wiring remains the most popular technique for primary sternal closure. Recently, a multifilament cable wiring system (Pioneer Surgical Technology Inc., Marquette, MI, USA) was introduced for sternal closure and has gained wide acceptance due to its superior resistance to tension. We aimed to compare conventional steel wiring to multifilament cable fixation for sternal closure in patients undergoing major cardiac surgery. Data were collected retrospectively on 1,354 patients who underwent sternal closure after major cardiac surgery, using either the multifilament cable wiring system or conventional steel wires between January 2009 and October 2010. The surgical outcomes of these two groups of patients were compared using propensity score matching based on 18 baseline patient characteristics. Propensity score matching yielded 392 pairs of patients in the two groups whose baseline profiles showed no significant differences. No significant differences between the two groups were observed in the rates of early mortality (2.0% vs. 1.3%, p=0.578), major wound complications requiring reconstruction (1.3% vs. 1.3%, p>0.99), minor wound complications (3.6% vs. 2.0%, p=0.279), or mediastinitis (0.8% vs. 1.0%, p=1.00). Patients in the multifilament cable group had fewer sternal bleeding events than those in the conventional wire group, but this tendency was not statistically significant (4.3% vs. 7.4%, p=0.068). The surgical outcomes of sternal closure using multifilament cable wires were comparable to those observed when conventional steel wires were used. Therefore, the multifilament cable wiring system may be considered a viable option for sternal closure in patients undergoing major cardiac surgery.

Thermal hydraulic evaluation of advanced wire-wrapped assemblies

International Nuclear Information System (INIS)

Wei, J.P.

1975-01-01

The thermal-hydraulic analyses presented in this report are based on application of the subchannel concept in association with the use of bulk parameters for coolant velocity and coolant temperature within a subchannel. The interactions between subchannels are due to turbulent interchange, pressure-induced diversion crossflow, directed sweeping crossflow induced by the helical wire wrap, and transverse thermal conduction. The FULMIX-II computer program was successfully developed to perform the steady-state temperature predictions for LMFBR fuel assemblies with the reference straight-start design and the advanced wire-wrap designs. Predicted steady-state temperature profiles are presented for a typical CRBRP 217-rod wire-wrapped assembly with the selected wire-wrap designs

Non-linear Imaging using an Experimental Synthetic Aperture Real Time Ultrasound Scanner

DEFF Research Database (Denmark)

Rasmussen, Joachim; Du, Yigang; Jensen, Jørgen Arendt

2011-01-01

This paper presents the first non-linear B-mode image of a wire phantom using pulse inversion attained via an experimental synthetic aperture real-time ultrasound scanner (SARUS). The purpose of this study is to implement and validate non-linear imaging on SARUS for the further development of new...... non-linear techniques. This study presents non-linear and linear B-mode images attained via SARUS and an existing ultrasound system as well as a Field II simulation. The non-linear image shows an improved spatial resolution and lower full width half max and -20 dB resolution values compared to linear...

TRANSMISSION LINE-WIRE DANCING (GALLOPING – LYAPUNOV INSTABILITY

Directory of Open Access Journals (Sweden)

V. I. Vanko

2014-01-01

Full Text Available This article describes aerodynamic losses of damping, or aerodynamic instability, which we observe in experiments and in engineering practice. As applied to industrial high-voltage lines this phenomenon is usually called galloping (dancing of phase line wires. This phenolmenon can be explained by Lyapunov’s instability of equilibrium state of wires profile (cross-section. In addition to known condition of Grauert-den-Hartog’s instability there was obtained practical condition of instability, which depends only on stationary aerodynamic profile’s factor – dimensionless coefficient of head resistance and lift coefficient, and also on their derivative with respect to the angle of attack.There was suggested an effective numerical-analytical method of investigation of stability for equilibrium of profile’s state in flow, which was developed at the department “Applied mathematics” of Bauman MSTU. This method allows to determine the stationary aerodynamics characteristics of profile by numerical simulation of profile flow under different angles of attack by vortex element method and later on the application of analytical conditions of stability and Lyapunov’s instability of equilibrium positions. The obtained results during the investigation of rhombic and square profiles stability, as well as general profile of iced wire, and their comparisons with the known experiments’ results in aerodynamic tubes indicate the precision of developed methods and algorithms. The usage of mesh-free Lagrange method of vortex elements and software for their realization allows to solve also dual problems of aerohydroelasticity and to carry out direct numerical simulation of profile movement in flow. In this article the investigations’ results of different authors in this field were taken into account.

Determining the surface roughness coefficient by 3D Scanner

Directory of Open Access Journals (Sweden)

Karmen Fifer Bizjak

2010-12-01

Full Text Available Currently, several test methods can be used in the laboratory to determine the roughness of rock joint surfaces.However, true roughness can be distorted and underestimated by the differences in the sampling interval of themeasurement methods. Thus, these measurement methods produce a dead zone and distorted roughness profiles.In this paper a new rock joint surface roughness measurement method is presented, with the use of a camera-typethree-dimensional (3D scanner as an alternative to current methods. For this study, the surfaces of ten samples oftuff were digitized by means of a 3D scanner, and the results were compared with the corresponding Rock JointCoefficient (JRC values. Up until now such 3D scanner have been mostly used in the automotive industry, whereastheir use for comparison with obtained JRC coefficient values in rock mechanics is presented here for the first time.The proposed new method is a faster, more precise and more accurate than other existing test methods, and is apromising technique for use in this area of study in the future.

Effects of the use of a flat wire electrode in gas metal arc welding and fuzzy logic model for the prediction of weldment shape profile

Energy Technology Data Exchange (ETDEWEB)

Karuthapandi, Sripriyan; Thyla, P. R. [PSG College of Technology, Coimbatore (India); Ramu, Murugan [Amrita University, Ettimadai (India)

2017-05-15

This paper describes the relationships between the macrostructural characteristics of weld beads and the welding parameters in Gas metal arc welding (GMAW) using a flat wire electrode. Bead-on-plate welds were produced with a flat wire electrode and different combinations of input parameters (i.e., welding current, welding speed, and flat wire electrode orientation). The macrostructural characteristics of the weld beads, namely, deposition, bead width, total bead width, reinforcement height, penetration depth, and depth of HAZ were investigated. A mapping technique was employed to measure these characteristics in various segments of the weldment zones. Results show that the use of a flat wire electrode improves the depth-to-width (D/W) ratio by 16.5 % on average compared with the D/W ratio when a regular electrode is used in GMAW. Furthermore, a fuzzy logic model was established to predict the effects of the use of a flat electrode on the weldment shape profile with varying input parameters. The predictions of the model were compared with the experimental results.

Effect of wire shape on wire array discharge

International Nuclear Information System (INIS)

Shimomura, N.; Tanaka, Y.; Yushita, Y.; Nagata, M.; Teramoto, Y.; Katsuki, S.; Akiyama, H.

2001-01-01

Although considerable investigations have been reported on z-pinches to achieve nuclear fusion, little attention has been given from the point of view of how a wire array consisting of many parallel wires explodes. Instability existing in the wire array discharge has been shown. In this paper, the effect of wire shape in the wire array on unstable behavior of the wire array discharge is represented by numerical analysis. The claws on the wire formed in installation of wire may cause uniform current distribution on wire array. The effect of error of wire diameter in production is computed by Monte Carlo Method. (author)

Effect of wire shape on wire array discharge

Energy Technology Data Exchange (ETDEWEB)

Shimomura, N.; Tanaka, Y.; Yushita, Y.; Nagata, M. [University of Tokushima, Department of Electrical and Electronic Engineering, Tokushima (Japan); Teramoto, Y.; Katsuki, S.; Akiyama, H. [Kumamoto University, Department of Electrical and Computer Engineering, Kumamoto (Japan)

2001-09-01

Although considerable investigations have been reported on z-pinches to achieve nuclear fusion, little attention has been given from the point of view of how a wire array consisting of many parallel wires explodes. Instability existing in the wire array discharge has been shown. In this paper, the effect of wire shape in the wire array on unstable behavior of the wire array discharge is represented by numerical analysis. The claws on the wire formed in installation of wire may cause uniform current distribution on wire array. The effect of error of wire diameter in production is computed by Monte Carlo Method. (author)

Comparison of statistical sampling methods with ScannerBit, the GAMBIT scanning module

Energy Technology Data Exchange (ETDEWEB)

Martinez, Gregory D. [University of California, Physics and Astronomy Department, Los Angeles, CA (United States); McKay, James; Scott, Pat [Imperial College London, Department of Physics, Blackett Laboratory, London (United Kingdom); Farmer, Ben; Conrad, Jan [AlbaNova University Centre, Oskar Klein Centre for Cosmoparticle Physics, Stockholm (Sweden); Stockholm University, Department of Physics, Stockholm (Sweden); Roebber, Elinore [McGill University, Department of Physics, Montreal, QC (Canada); Putze, Antje [LAPTh, Universite de Savoie, CNRS, Annecy-le-Vieux (France); Collaboration: The GAMBIT Scanner Workgroup

2017-11-15

We introduce ScannerBit, the statistics and sampling module of the public, open-source global fitting framework GAMBIT. ScannerBit provides a standardised interface to different sampling algorithms, enabling the use and comparison of multiple computational methods for inferring profile likelihoods, Bayesian posteriors, and other statistical quantities. The current version offers random, grid, raster, nested sampling, differential evolution, Markov Chain Monte Carlo (MCMC) and ensemble Monte Carlo samplers. We also announce the release of a new standalone differential evolution sampler, Diver, and describe its design, usage and interface to ScannerBit. We subject Diver and three other samplers (the nested sampler MultiNest, the MCMC GreAT, and the native ScannerBit implementation of the ensemble Monte Carlo algorithm T-Walk) to a battery of statistical tests. For this we use a realistic physical likelihood function, based on the scalar singlet model of dark matter. We examine the performance of each sampler as a function of its adjustable settings, and the dimensionality of the sampling problem. We evaluate performance on four metrics: optimality of the best fit found, completeness in exploring the best-fit region, number of likelihood evaluations, and total runtime. For Bayesian posterior estimation at high resolution, T-Walk provides the most accurate and timely mapping of the full parameter space. For profile likelihood analysis in less than about ten dimensions, we find that Diver and MultiNest score similarly in terms of best fit and speed, outperforming GreAT and T-Walk; in ten or more dimensions, Diver substantially outperforms the other three samplers on all metrics. (orig.)

Verification of CTDI and Dlp values for a head tomography reported by the manufacturers of the CT scanners, using a CT dose profiler probe, a head phantom and a piranha electrometer

International Nuclear Information System (INIS)

Castillo C, E.; Garcia F, I. B.; Garcia H, J.; Roman L, S.; Salmeron C, O.

2015-10-01

The extensive use of Computed Tomography (CT) and the associated increase in patient dose calls for an accurate dose evaluation technique. The CT contributes up to 70% of the total dose given to patients during X-ray examinations. The rapid advancements in CT technology are placing new demands on the methods and equipment that are used for quality assurance. The wide beam widths found in CT scanners with multiple beam apertures make it impossible to use existing CT ionization chambers to measure the total dose given to the patient. Using a standard 10 cm CT ionization chamber may result in inaccurate measurements due to underestimation of the dose profile for wide beams. The use a CT dose profiler based on solid-state technology and the Piranha electrometer from RTI electronics provides a potential solution to the arising concerns over patient dose. This study intend to evaluate the feasibility and accuracy of CT Dose Index (CTDI) and Dose Length Product (Dlp) values for a head tomography reported by the manufacturers of the CT scanners at each study. (Author)

Verification of CTDI and Dlp values for a head tomography reported by the manufacturers of the CT scanners, using a CT dose profiler probe, a head phantom and a piranha electrometer

Energy Technology Data Exchange (ETDEWEB)

Castillo C, E.; Garcia F, I. B.; Garcia H, J.; Roman L, S. [Servicios de Salud de Michoacan, Centro Estatal de Atencion Oncologica, Gertrudis Bocanegra No. 300, Col. Cuauhtemoc, 58020 Morelia, Michoacan (Mexico); Salmeron C, O., E-mail: edithcastillocorona@gmail.com [Servicios de Salud de Michoacan, Hospital General Dr. Miguel Silva, Isidro Huarte s/n, Centro Historico, 58000 Morelia, Michoacan (Mexico)

2015-10-15

The extensive use of Computed Tomography (CT) and the associated increase in patient dose calls for an accurate dose evaluation technique. The CT contributes up to 70% of the total dose given to patients during X-ray examinations. The rapid advancements in CT technology are placing new demands on the methods and equipment that are used for quality assurance. The wide beam widths found in CT scanners with multiple beam apertures make it impossible to use existing CT ionization chambers to measure the total dose given to the patient. Using a standard 10 cm CT ionization chamber may result in inaccurate measurements due to underestimation of the dose profile for wide beams. The use a CT dose profiler based on solid-state technology and the Piranha electrometer from RTI electronics provides a potential solution to the arising concerns over patient dose. This study intend to evaluate the feasibility and accuracy of CT Dose Index (CTDI) and Dose Length Product (Dlp) values for a head tomography reported by the manufacturers of the CT scanners at each study. (Author)

Complete-arch accuracy of intraoral scanners.

Science.gov (United States)

Treesh, Joshua C; Liacouras, Peter C; Taft, Robert M; Brooks, Daniel I; Raiciulescu, Sorana; Ellert, Daniel O; Grant, Gerald T; Ye, Ling

2018-04-30

Intraoral scanners have shown varied results in complete-arch applications. The purpose of this in vitro study was to evaluate the complete-arch accuracy of 4 intraoral scanners based on trueness and precision measurements compared with a known reference (trueness) and with each other (precision). Four intraoral scanners were evaluated: CEREC Bluecam, CEREC Omnicam, TRIOS Color, and Carestream CS 3500. A complete-arch reference cast was created and printed using a 3-dimensional dental cast printer with photopolymer resin. The reference cast was digitized using a laboratory-based white light 3-dimensional scanner. The printed reference cast was scanned 10 times with each intraoral scanner. The digital standard tessellation language (STL) files from each scanner were then registered to the reference file and compared with differences in trueness and precision using a 3-dimensional modeling software. Additionally, scanning time was recorded for each scan performed. The Wilcoxon signed rank, Kruskal-Wallis, and Dunn tests were used to detect differences for trueness, precision, and scanning time (α=.05). Carestream CS 3500 had the lowest overall trueness and precision compared with Bluecam and TRIOS Color. The fourth scanner, Omnicam, had intermediate trueness and precision. All of the scanners tended to underestimate the size of the reference file, with exception of the Carestream CS 3500, which was more variable. Based on visual inspection of the color rendering of signed differences, the greatest amount of error tended to be in the posterior aspects of the arch, with local errors exceeding 100 μm for all scans. The single capture scanner Carestream CS 3500 had the overall longest scan times and was significantly slower than the continuous capture scanners TRIOS Color and Omnicam. Significant differences in both trueness and precision were found among the scanners. Scan times of the continuous capture scanners were faster than the single capture scanners

Beam property measurement of a 300-kV ion source test stand for a 1-MV electrostatic accelerator

Science.gov (United States)

Park, Sae-Hoon; Kim, Dae-Il; Kim, Yu-Seok

2016-09-01

The KOMAC (Korea Multi-purpose Accelerator Complex) has been developing a 300-kV ion source test stand for a 1-MV electrostatic accelerator for industrial purposes. A RF ion source was operated at 200 MHz with its matching circuit. The beam profile and emittance were measured behind an accelerating column to confirm the beam property from the RF ion source. The beam profile was measured at the end of the accelerating tube and at the beam dump by using a beam profile monitor (BPM) and wire scanner. An Allison-type emittance scanner was installed behind the beam profile monitor (BPM) to measure the beam density in phase space. The measurement results for the beam profile and emittance are presented in this paper.

Practicality of profile-wire screen in reducing entrainment and impingement

International Nuclear Information System (INIS)

Hanson, B.N.; Bason, W.H.; Beitz, B.E.; Charles, K.E.

1978-01-01

Experimental studies indicated that 1.01-mm slot profile-wire well screen operated at an intake velocity of 15.24 cm/s virtually eliminated impingement of fishes larger than 15 mm fork length (FL). Intake velocities as high as 53.34 cm/s produced low impingement. Tests of fish less than 40 mm FL held near a functioning intake (15.24 cm/s) for as long as 3 hr yielded no impingement or stress. Many striped bass between 8 and 17 mm FL were capable of resisting impingement at more than 30.48 cm/s velocity for longer than 30 min; larger specimens (12 to 17 mm) showed excellent ability to escape when impinged. The screen excluded virtually all striped bass eggs from the cooling water. Preliminary egg mortality studies indicate that at least 95% survival can be expected at an approach velocity of 15.24 cm/s and impingement durations up to 2 min. Fouling studies showed that screens were highly resistant to clogging, essentially self-cleaning in a current, and easily backwashed. In-situ studies in the Chesapeake and Delaware Canal have shown that a 61.0- x 76.2-cm, 1.01-mm-slot screen is capable of providing its designed capacity for weeks without backwashing or cleaning. Biofouling proved to be the greatest operational problem. Entrainment samples from the in-situ intake have shown significant reductions in organisms/m 3 of filtered versus ambient water

Neurosurgical operating computerized tomographic scanner system. The CT scanner in the operating theater

Energy Technology Data Exchange (ETDEWEB)

Okudera, Hiroshi; Sugita, Kenichiro; Kobayashi, Shigeaki; Kimishima, Sakae; Yoshida, Hisashi

1988-12-01

A neurosurgical operating computerized tomography scanner system is presented. This system has been developed for obtaining intra- and postoperative CT images in the operating room. A TCT-300 scanner (manufactured by the Toshiba Co., Tokyo) is placed in the operating room. The realization of a true intraoperative CT image requires certain improvements in the CT scanner and operating table. To adjust the axis of the co-ordinates of the motor system of the MST-7000 microsurgical operating table (manufactured by the Mizuho Ika Co., Tokyo) to the CT scanner, we have designed an interface and a precise motor system so that the computer of the CT scanner can directly control the movement of the operating table. Furthermore, a new head-fixation system has been designed for producing artifact-free intraoperative CT images. The head-pins of the head-fixation system are made of carbon-fiber bars and titanium tips. A simulation study of the total system in the operating room with the CT scanner, operating table, and head holder using a skull model yielded a degree of error similar to that in the phantom testing of the original scanner. Three patients underwent resection of a glial tumor using this system. Intraoperative CT scans taken after dural opening showed a bulging of the cortex, a shift in the central structure, and a displacement of the cortical subarachnoid spaces under the influence of gravity. With a contrast medium the edge of the surrounding brain after resection was enhanced and the residual tumor mass was demonstrated clearly. This system makes it possible to obtain a noninvasive intraoperative image in a situation where structural shifts are taking place.

Long-Range WindScanner System

DEFF Research Database (Denmark)

Vasiljevic, Nikola; Lea, Guillaume; Courtney, Michael

2016-01-01

The technical aspects of a multi-Doppler LiDAR instrument, the long-range WindScanner system, are presented accompanied by an overview of the results from several field campaigns. The long-range WindScanner system consists of three spatially-separated, scanning coherent Doppler LiDARs and a remote......-rangeWindScanner system measures the wind field by emitting and directing three laser beams to intersect, and then scanning the beam intersection over a region of interest. The long-range WindScanner system was developed to tackle the need for high-quality observations of wind fields on scales of modern wind turbine...

Computerized tomographic scanner with shaped radiation filter

International Nuclear Information System (INIS)

Carlson, R.W.; Walters, R.G.

1981-01-01

The invention comprises a shaped filter and a filter correction circuitry for computerized tomographic scanners. The shaped filter is a generally u-shaped block of filter material which is adapted to be mounted between the source of radiation and the scan circle. The u-shaped block has a parabolic recess. The filter material may be beryllium, aluminum, sulphur, calcium, titanium, erbium, copper, and compounds including oxides and alloys thereof. The filter correction circuit comprises a first filter correction profile adding circuit for adding a first scaler valve to each intensity valve in a data line. The data line is operated on by a beam hardness correction polynomial. After the beam hardness polynomial correction operation, a second filter correction circuit adds a second filter correction profile consisting of a table of scalor values, one corresponding to each intensity reading in the data line

The cobalt-60 container scanner

International Nuclear Information System (INIS)

Jigang, A.; Liye, Z.; Yisi, L.; Haifeng, W.; Zhifang, W.; Liqiang, W.; Yuanshi, Z.; Xincheng, X.; Furong, L.; Baozeng, G.; Chunfa, S.

1997-01-01

The Institute of Nuclear Energy Technology (INET) has successfully designed and constructed a container (cargo) scanner, which uses cobalt-60 of 100-300 Ci as radiation source. The following performances of the Cobalt-60 container scanner have been achieved at INET: a) IQI (Image Quality Indicator) - 2.5% behind 100 mm of steel; b) CI (Contrast Indicator) - 0.7% behind 100 mm of steel; c) SP (Steel Penetration) - 240 mm of steel; d) Maximum Dose per Scanning - 0.02mGy; e) Throughput - twenty 40-foot containers per hour. These performances are equal or similar to those of the accelerator scanners. Besides these nice enough inspection properties, the Cobalt-60 scanner possesses many other special features which are better than accelerator scanners: a) cheap price - it will be only or two tenths of the accelerator scanner's; b) low radiation intensity - the radiation protection problem is much easier to solve and a lot of money can be saved on the radiation shielding building; c) much smaller area for installation and operation; d) simple operation and convenient maintenance; e) high reliability and stability. The Cobalt-60 container (or cargo) scanner is satisfied for boundary customs, seaports, airports and railway stations etc. Because of the nice special features said above, it is more suitable to be applied widely. Its high properties and low price will make it have much better application prospects

Scanner calibration revisited

Directory of Open Access Journals (Sweden)

Pozhitkov Alexander E

2010-07-01

Full Text Available Abstract Background Calibration of a microarray scanner is critical for accurate interpretation of microarray results. Shi et al. (BMC Bioinformatics, 2005, 6, Art. No. S11 Suppl. 2. reported usage of a Full Moon BioSystems slide for calibration. Inspired by the Shi et al. work, we have calibrated microarray scanners in our previous research. We were puzzled however, that most of the signal intensities from a biological sample fell below the sensitivity threshold level determined by the calibration slide. This conundrum led us to re-investigate the quality of calibration provided by the Full Moon BioSystems slide as well as the accuracy of the analysis performed by Shi et al. Methods Signal intensities were recorded on three different microarray scanners at various photomultiplier gain levels using the same calibration slide from Full Moon BioSystems. Data analysis was conducted on raw signal intensities without normalization or transformation of any kind. Weighted least-squares method was used to fit the data. Results We found that initial analysis performed by Shi et al. did not take into account autofluorescence of the Full Moon BioSystems slide, which led to a grossly distorted microarray scanner response. Our analysis revealed that a power-law function, which is explicitly accounting for the slide autofluorescence, perfectly described a relationship between signal intensities and fluorophore quantities. Conclusions Microarray scanners respond in a much less distorted fashion than was reported by Shi et al. Full Moon BioSystems calibration slides are inadequate for performing calibration. We recommend against using these slides.

Developing and Testing SpaceWire Devices and Networks

Science.gov (United States)

Parkes, Steve; Mills, Stuart

2014-08-01

SpaceWire is a data-handling network for use on-board spacecraft, which connects together instruments, mass- memory, processors, downlink telemetry, and other on- board sub-systems [1]. SpaceWire is simple to implement and has some specific characteristics that help it support data-handling applications in space: high-speed, low-power, simplicity, relatively low implementation cost, and architectural flexibility making it ideal for many space missions. SpaceWire provides high-speed (2 Mbits/s to 200 Mbits/s), bi- directional, full-duplex data-links, which connect together SpaceWire enabled equipment. Data-handling networks can be built to suit particular applications using point-to-point data-links and routing switches.Since the SpaceWire standard was published in January 2003, it has been adopted by ESA, NASA, JAXA and RosCosmos for many missions and is being widely used on scientific, Earth observation, commercial and other spacecraft. High-profile missions using SpaceWire include: Gaia, ExoMars rover, Bepi- Colombo, James Webb Space Telescope, GOES-R, Lunar Reconnaissance Orbiter and Astro-H.The development and testing of the SpaceWire links and networks used on these and many other spacecraft currently under development, requires a comprehensive array of test equipment. In this paper the requirements for test equipment fulfilling key test functions are outlined and then equipment that meets these requirements is described. Finally the all-important software that operates with the test equipment is introduced.

wire chamber

CERN Multimedia

Proportional multi-wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle. Proportional wire chambers allow a much quicker reading than the optical or magnetoscriptive readout wire chambers.

Thermal Recovery from Cold-Working in Type K Bare-Wire Thermocouples

Science.gov (United States)

Greenen, A. D.; Webster, E. S.

2017-12-01

Cold-working of most thermocouples has a significant, direct impact on the Seebeck coefficient which can lead to regions of thermoelectric inhomogeneity and accelerated drift. Cold-working can occur during the wire swaging process, when winding the wire onto a bobbin, or during handling by the end user—either accidentally or deliberately. Swaging-induced cold-work in thermocouples, if uniformly applied, may result in a high level of homogeneity. However, on exposure to elevated temperatures, the subsequent recovery process from the cold-working can then result in significant drift, and this can in turn lead to erroneous temperature measurements, often in excess of the specified manufacturer tolerances. Several studies have investigated the effects of cold-work in Type K thermocouples usually by bending, or swaging. However, the amount of cold-work applied to the thermocouple is often difficult to quantify, as the mechanisms for applying the strains are typically nonlinear when applied in this fashion. A repeatable level of cold-working is applied to the different wires using a tensional loading apparatus to apply a known yield displacement to the thermoelements. The effects of thermal recovery from cold-working can then be accurately quantified as a function of temperature, using a linear gradient furnace and a high-resolution homogeneity scanner. Variation in these effects due to differing alloy compositions in Type K wire is also explored, which is obtained by sourcing wire from a selection of manufacturers. The information gathered in this way will inform users of Type K thermocouples about the potential consequences of varying levels of cold-working and its impact on the Seebeck coefficient at a range of temperatures between ˜ 70°C and 600° C. This study will also guide users on the temperatures required to rapidly alleviate the effects of cold-working using thermal annealing treatments.

Computed tomography scanner applied to soil compaction studies

International Nuclear Information System (INIS)

Vaz, C.M.P.

1989-11-01

The soil compaction problem was studied using a first generation computed tomography scanner (CT). This apparatus gets images of soil cross sections samples, with resolution of a few millimeters. We performed the following laboratory and field experiments: basic experiments of equipment calibrations and resolutions studies; measurements of compacted soil thin layers; measurements of soil compaction caused by agricultural tools; stress-strain modelling in confined soil sample, with several moisture degree; characterizations of soil bulk density profile with samples collected in a hole (trench), comparing with a cone penetrometer technique. (author)

Multi-wire chamber system for heavy ion beam monitoring at the Bevalac

International Nuclear Information System (INIS)

Cuperus, J.; Morgado, R.

1975-03-01

Horizontal and vertical integrated beam-current profiles are generated by a system of multi-wire chambers (32 wires/profile) operating in either the ionization or proportional mode. Sixteen distinct displays (1024 words) are digitally stored and any four may be simultaneously displayed. A new display can be generated at 64 ms intervals. A central control unit selects the mode of operation, the amount of delay after an appropriate trigger, the chamber integration time, and the particular chambers to be displayed. Operating in the proportional mode, the system can detect relativistic heavy-ion beam intensities as low as 10 4 charges cm -2 sec -1 . (U.S.)

Comparison of PIV and Hot-Wire statistics of turbulent boundary layer

International Nuclear Information System (INIS)

Dróżdż, A; Uruba, V

2014-01-01

The paper shows a cross checking of turbulent boundary layer measurements using large field of view PIV and hot-wire anemometry techniques. The time-resolved PIV method was used for the experiments. The measuring plane was oriented perpendicularly to the wall and parallel to the mean flow. Hot wire measurement has been performed using the special probe with perpendicular hot wire. The HW point measurements were performed in the same place as PIV experiments. The hot-wire probe has the wire length of l + < 20 in considered range of Reynolds numbers. Various evaluation methods were applied on PIV data. The profiles of statistical characteristics of streamwise velocity components were evaluated from the data. Mean values, standard deviations as well as skewness and kurtosis coefficients were compared for a few values of Re θ . Reynolds number ranges from 1000 to 5500. The result shows that with the increasing Reynolds number the attenuation of fluctuations maximum in PIV measurements occurs with respect to Hot-Wire measurements, however representation of velocity fluctuations using the PIV method is satisfactory. The influence of wall-normal fluctuation component on Hot-Wire near wall peak was also investigated.

Quality assurance of computed tomography scanner beams in diagnostic radiology

International Nuclear Information System (INIS)

Lindskoug, B.A.

1989-01-01

The number of computed tomography (CT) scanners in diagnostic radiology is increasing, to the extent that they are now found in relatively small hospitals. These hospitals do not have local physicists available and so methods must be developed to allow quality assurance to be carried out at distant laboratories. Several different types of solid water phantoms are available with various built-in test objects that may supply sufficient information about the many parameters that must be checked. The dose distributions, however, are usually not so well considered, although the connection between image quality and absorbed dose must be known for optimal use of a CT scanner. By introducing thermoluminescent dosemeters (TLDs) into a commercial phantom (RMI), it was possible to measure the absorbed dose profile and the line integral of the absorbed dose across the slit. The computer-guided readout of the TLDs gives the absorbed dose, the average dose and half maximum width, absorbed dose curve, and also the line integral of the peak. The only modification of the phantom was five holes, drilled at strategic positions, that did not influence the built-in test objects. This single measurement provides an appropriate monthly quality assurance check of the CT scanner with little extra effort. (author)

Thermosonic wire bonding of IC devices using palladium wire

International Nuclear Information System (INIS)

Shze, J.H.; Poh, M.T.; Tan, R.M.

1996-01-01

The feasibility of replacing gold wire by palladium wire in thermosonic wire bonding of CMOS and bipolar devices are studied in terms of the manufacturability, physical, electrical and assembly performance. The results that palladium wire is a viable option for bonding the bipolar devices but not the CMOS devices

Monte Carlo dose calibration in CT scanner

International Nuclear Information System (INIS)

Yadav, Poonam; Ramasubramanian, V.; Subbaiah, K.V.; Thayalan, K.

2008-01-01

Computed Tomography (CT) scanner is a high radiation imaging modality compared to radiography. The dose from a CT examination can vary greatly depending on the particular CT scanner used, the area of the body examined, and the operating parameters of the scan. CT is a major contributor to collective effective dose in diagnostic radiology. Apart from the clinical benefits, the widespread use of multislice scanner is increasing radiation level to patient in comparison with conventional CT scanner. So, it becomes necessary to increase awareness about the CT scanner. (author)

WindScanner.eu - a new remote sensing research infrastructure for on- and offshore wind energy

Energy Technology Data Exchange (ETDEWEB)

Mikkelsen, Torben; Knudsen, Soeren; Sjoeholm, M.; Angeloua, N.; Tegtmeier, A. [Technical Univ. og Denmark. DTU Wind Energy, DTU Risoe Campus, Roskilde (Denmark)

2012-07-01

A new remote sensing based research infrastructure for atmospheric boundary-layer wind and turbulence measurements named WindScanner have during the past three years been in its early phase of development at DTU Wind Energy in Denmark. During the forthcoming three years the technology will be disseminated throughout Europe to pilot European wind energy research centers. The new research infrastructure will become an open source infrastructure that also invites collaboration with wind energy related atmospheric scientists and wind energy industry overseas. Recent achievements with 3D WindScanners and spin-off innovation activity are described. The Danish WindScanner.dk research facility is build from new and fast-scanning remote sensing equipment spurred from achievements within fiber optics and telecommunication technologies. At the same time the wind energy society has demanded excessive 3D wind flow and ever taller wind profile measurements for the wind energy resource assessment studies on- and off shore of the future. Today, hub heights on +5 MW wind turbines exceed the 100 m mark. At the Danish DTU test site Oesterild testing is ongoing with a Siemens turbine with hub height 120 meters and a rotor diameter of 154 meters; hence its blade tips reaches almost 200 meters into the sky. The wind speed profiles over the rotor planes are consequently no longer representatively measured by a single cup anemometer at hub height from a nearby met-mast; power curve assessment as well as turbine control call for multi-height multi point measurement strategies of wind speed and wind shear within the turbines entire rotor plane. The development of our new remote sensing-based WindScanner.dk facility as well as the first measurement results obtained to date are here presented, including a first wind lidar measurement of turbulence in complex terrain within an internal boundary layer developing behind an escarpment. Also measurements of wind speed and direction profiles

Vibration of signal wires in wire detectors under irradiation

International Nuclear Information System (INIS)

Bojko, I.R.; Shelkov, G.A.; Dodonov, V.I.; Ignatenko, M.A.; Nikolenko, M.Yu.

1995-01-01

Radiation-induced vibration of signal wires in wire detectors is found and explained. The phenomenon is based on repulsion of a signal wire with a positive potential and a cloud of positive ions that remains after neutralization of the electron part of the avalanche formed in the course of gas amplification. Vibration with a noticeable amplitude may arise from fluctuations of repulsive forces, which act on the wire and whose sources are numerous ion clusters. A formula is obtained which allows wire oscillations to be estimated for all types of wire detectors. Calculation shows that oscillations of signal wires can be substantial for the coordinate accuracy of a detector working in the limited streamer mode at fluxes over 10 5 particles per second per wire. In the proportional mode an average oscillation amplitude can be as large as 20-30 μm at some detector parameters and external radiation fluxes over 10 5 . The experimental investigations show that the proposed model well describes the main features of the phenomenon. 6 refs., 8 figs

NMR-CT scanner

International Nuclear Information System (INIS)

Kose, Katsumi; Sato, Kozo; Sugimoto, Hiroshi; Sato, Masataka.

1983-01-01

A brief explanation is made on the imaging methods for a practical diagnostic NMR-CT scanner : A whole-body NMR-CT scanner utilizing a resistive magnet has been developed by Toshiba in cooperation with the Institute for Solid State Physics, the University of Tokyo. Typical NMR-CT images of volunteers and patients obtained in the clinical experiments using this device are presented. Detailed specifications are also shown about the practical NMR-CTs which are to be put on the market after obtaining the government approval. (author)

Wire Chamber

CERN Multimedia

Magnetoscriptive readout wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

Wire chamber

CERN Multimedia

1967-01-01

Magnetoscriptive readout wire chamber.Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

Static friction of stainless steel wire rope–rubber contacts.

NARCIS (Netherlands)

Loeve, A.J.; Krijger, T.; Mugge, W.; Breedveld, P.; Dodou, D.; Dankelman, J.

2014-01-01

Little is known about static friction of stainless-steel wire ropes ('cables') in contact with soft rubbers, an interface of potential importance for rigidifiable medical instruments. Although friction theories imply that the size and profile of the cables affect static friction, there are no

A noble refractive optical scanner with linear response

Science.gov (United States)

Mega, Yair J.; Lai, Zhenhua; DiMarzio, Charles A.

2013-03-01

Many applications in various fields of science and engineering use steered optical beam systems. Currently, many methods utilize mirrors in order to steer the beam. However, this approach is an off-axis solution, which normally increases the total size of the system as well as its error and complexity. Other methods use a "Risely Prisms" based solution, which is on-axis solution, however it poses some difficulties from an engineering standpoint, and therefore isn't widely used. We present here a novel technique for steering a beam on its optical axis with a linear deflection response. We derived the formulation for the profile required of the refractive optical component necessary for preforming the beam steering. The functionality of the device was simulated analytically using Matlab, as well as using a ray-tracing software, Zemax, and showed agreement with the analytical model. An optical element was manufactured based on the proposed design and the device was tested. The results show agreement with our hypothesis. We also present some proposed geometries of the several other devices, all based on the same concept, which can be used for higher performance applications such as two-dimensional scanner, video rate scanner etc.

Anatomic Assessment of K-Wire Trajectory for Transverse Percutaneous Fixation of Small Finger Metacarpal Fractures: A Cadaveric Study.

Science.gov (United States)

Grandizio, Louis C; Speeckaert, Amy; Kozick, Zach; Klena, Joel C

2018-01-01

The purpose of this cadaveric study is to evaluate the trajectory of percutaneous transverse Kirschner wire (K-wire) placement for fifth metacarpal fractures relative to the sagittal profile of the fifth metacarpal in order to develop a targeting strategy for the treatment of fifth metacarpal fractures. Using 12 unmatched fresh human upper limbs, we evaluated the trajectory of percutaneous transverse K-wire placement relative to the sagittal profile of the fifth metacarpal in order to develop a targeting strategy for treatment of fifth metacarpal fractures. The midpoint of the small and ring finger metacarpals in the sagittal plane was identified at 3 points. At each point, a K-wire was inserted from the small finger metacarpal into the midpoint of the ring finger metacarpal ("center-center" position). The angle of the transverse K-wire relative to the table needed to achieve a center-center position averaged 20.8°, 18.9°, and 16.7° for the proximal diaphysis, middiaphysis, and the collateral recess, respectively. Approximately 80% of transversely placed K-wires obtained purchase in the long finger metacarpal. These results can serve as a guide to help surgeons in the accurate placement of percutaneous K-wires for small finger metacarpal fractures and may aid in surgeon training.

Fast, high-resolution 3D dosimetry utilizing a novel optical-CT scanner incorporating tertiary telecentric collimation

International Nuclear Information System (INIS)

Sakhalkar, H. S.; Oldham, M.

2008-01-01

This study introduces a charge coupled device (CCD) area detector based optical-computed tomography (optical-CT) scanner for comprehensive verification of radiation dose distributions recorded in nonscattering radiochromic dosimeters. Defining characteristics include: (i) a very fast scanning time of ∼5 min to acquire a complete three-dimensional (3D) dataset, (ii) improved image formation through the use of custom telecentric optics, which ensures accurate projection images and minimizes artifacts from scattered and stray-light sources, and (iii) high resolution (potentially 50 μm) isotropic 3D dose readout. The performance of the CCD scanner for 3D dose readout was evaluated by comparison with independent 3D readout from the single laser beam OCTOPUS-scanner for the same PRESAGE dosimeters. The OCTOPUS scanner was considered the 'gold standard' technique in light of prior studies demonstrating its accuracy. Additional comparisons were made against calculated dose distributions from the ECLIPSE treatment-planning system. Dose readout for the following treatments were investigated: (i) a single rectangular beam irradiation to investigate small field and very steep dose gradient dosimetry away from edge effects, (ii) a 2-field open beam parallel-opposed irradiation to investigate dosimetry along steep dose gradients, and (iii) a 7-field intensity modulated radiation therapy (IMRT) irradiation to investigate dosimetry for complex treatment delivery involving modulation of fluence and for dosimetry along moderate dose gradients. Dose profiles, dose-difference plots, and gamma maps were employed to evaluate quantitative estimates of agreement between independently measured and calculated dose distributions. Results indicated that dose readout from the CCD scanner was in agreement with independent gold-standard readout from the OCTOPUS-scanner as well as the calculated ECLIPSE dose distribution for all treatments, except in regions within a few millimeters of the

Comparison of the mechanical properties of rotary instruments made of conventional nickel-titanium wire, M-wire, or nickel-titanium alloy in R-phase.

Science.gov (United States)

Lopes, Hélio P; Gambarra-Soares, Thaiane; Elias, Carlos N; Siqueira, José F; Inojosa, Inês F J; Lopes, Weber S P; Vieira, Victor T L

2013-04-01

This study compared the mechanical properties of endodontic instruments made of conventional nickel-titanium (NiTi) wire (K(3) and Revo-S SU), M-Wire (ProFile Vortex), or NiTi alloy in R-phase (K(3)XF). The test instruments were subjected to mechanical tests to evaluate resistance to bending (flexibility), cyclic fatigue, and torsional load in clockwise rotation. Data were statistically evaluated by the analysis of variance test and the Student-Newman-Keuls test for multiple comparisons. In the bending resistance test, flexibility decreased in the following order: K(3)XF > Revo-S SU > ProFile Vortex > K(3). The ranking in the fatigue resistance test was the following: K(3)XF > K(3) > ProFile Vortex > Revo-S SU. In the torsional assay, the angular deflection at failure decreased in the following order: K(3)XF > Revo-S SU > K(3) > ProFile Vortex. For the maximum torque values, the ranking was K(3) > K(3)XF > ProFile Vortex > Revo-S SU. The results showed that the K(3)XF instrument, which is made of NiTi alloy in R-phase, had the overall best performance in terms of flexibility, angular deflection at failure, and cyclic fatigue resistance. In addition to the alloy from which the instrument is manufactured, the design and dimensions are important determinants of the mechanical performance of endodontic instruments. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The feasibility of a scanner-independent technique to estimate organ dose from MDCT scans: Using CTDIvol to account for differences between scanners

International Nuclear Information System (INIS)

Turner, Adam C.; Zankl, Maria; DeMarco, John J.; Cagnon, Chris H.; Zhang Di; Angel, Erin; Cody, Dianna D.; Stevens, Donna M.; McCollough, Cynthia H.; McNitt-Gray, Michael F.

2010-01-01

Purpose: Monte Carlo radiation transport techniques have made it possible to accurately estimate the radiation dose to radiosensitive organs in patient models from scans performed with modern multidetector row computed tomography (MDCT) scanners. However, there is considerable variation in organ doses across scanners, even when similar acquisition conditions are used. The purpose of this study was to investigate the feasibility of a technique to estimate organ doses that would be scanner independent. This was accomplished by assessing the ability of CTDI vol measurements to account for differences in MDCT scanners that lead to organ dose differences. Methods: Monte Carlo simulations of 64-slice MDCT scanners from each of the four major manufacturers were performed. An adult female patient model from the GSF family of voxelized phantoms was used in which all ICRP Publication 103 radiosensitive organs were identified. A 120 kVp, full-body helical scan with a pitch of 1 was simulated for each scanner using similar scan protocols across scanners. From each simulated scan, the radiation dose to each organ was obtained on a per mA s basis (mGy/mA s). In addition, CTDI vol values were obtained from each scanner for the selected scan parameters. Then, to demonstrate the feasibility of generating organ dose estimates from scanner-independent coefficients, the simulated organ dose values resulting from each scanner were normalized by the CTDI vol value for those acquisition conditions. Results: CTDI vol values across scanners showed considerable variation as the coefficient of variation (CoV) across scanners was 34.1%. The simulated patient scans also demonstrated considerable differences in organ dose values, which varied by up to a factor of approximately 2 between some of the scanners. The CoV across scanners for the simulated organ doses ranged from 26.7% (for the adrenals) to 37.7% (for the thyroid), with a mean CoV of 31.5% across all organs. However, when organ doses

Occurrence and characteristics of mutual interference between LIDAR scanners

Science.gov (United States)

Kim, Gunzung; Eom, Jeongsook; Park, Seonghyeon; Park, Yongwan

2015-05-01

The LIDAR scanner is at the heart of object detection of the self-driving car. Mutual interference between LIDAR scanners has not been regarded as a problem because the percentage of vehicles equipped with LIDAR scanners was very rare. With the growing number of autonomous vehicle equipped with LIDAR scanner operated close to each other at the same time, the LIDAR scanner may receive laser pulses from other LIDAR scanners. In this paper, three types of experiments and their results are shown, according to the arrangement of two LIDAR scanners. We will show the probability that any LIDAR scanner will interfere mutually by considering spatial and temporal overlaps. It will present some typical mutual interference scenario and report an analysis of the interference mechanism.

Continuous versus step-by-step scanning mode of a novel 3D scanner for CyberKnife measurements

International Nuclear Information System (INIS)

Al Kafi, M Abdullah; Mwidu, Umar; Moftah, Belal

2015-01-01

The purpose of the study is to investigate the continuous versus step-by-step scanning mode of a commercial circular 3D scanner for commissioning measurements of a robotic stereotactic radiosurgery system. The 3D scanner was used for profile measurements in step-by-step and continuous modes with the intent of comparing the two scanning modes for consistency. The profile measurements of in-plane, cross-plane, 15 degree, and 105 degree were performed for both fixed cones and Iris collimators at depth of maximum dose and at 10 cm depth. For CyberKnife field size, penumbra, flatness and symmetry analysis, it was observed that the measurements with continuous mode, which can be up to 6 times faster than step-by-step mode, are comparable and produce scans nearly identical to step-by-step mode. When compared with centered step-by-step mode data, a fully processed continuous mode data gives rise to maximum of 0.50% and 0.60% symmetry and flatness difference respectfully for all the fixed cones and Iris collimators studied. - Highlights: • D scanner for CyberKnife beam data measurements. • Beam data analysis for continuous and step-by-step scan modes. • Faster continuous scanning data are comparable to step-by-step mode scan data.

Proportional counter with a wire-anode lying on the dielectric surface

International Nuclear Information System (INIS)

Strelkov, A.V.

1983-01-01

Proportional coUnter with wire-anode lying on the dielectric surface is described. The result of the accumulation of charges on the dielectric surface immediately near the wire-anode surface is that such a counter possesses electrostatic memory relative to distribution of the gas amplification coefficient along the anode. SUch a distribution can be received for example by means of irradiation by the neutrons or the γ-rays. The disposition of the wire-anode on the convex dielectric surface allows one to make the ring-shaped counters or the nonplane proportional chambers practically of any profile. However, the energy resolution of the counter with anode on the dielectric is worse than the resolution of counter with free anode particularly at the large gas amplification coefficient

Transverse Beam Halo Measurements at High Intensity Neutrino Source (HINS) using Vibrating Wire Monitor

Energy Technology Data Exchange (ETDEWEB)

Chung, M.; Hanna, B.; Scarpine, V.; Shiltsev, V.; Steimel, J.; Artinian, S.; Arutunian, S.

2015-02-26

The measurement and control of beam halos will be critical for the applications of future high-intensity hadron linacs. In particular, beam profile monitors require a very high dynamic range when used for the transverse beam halo measurements. In this study, the Vibrating Wire Monitor (VWM) with aperture 60 mm was installed at the High Intensity Neutrino Source (HINS) front-end to measure the transverse beam halo. A vibrating wire is excited at its resonance frequency with the help of a magnetic feedback loop, and the vibrating and sensitive wires are connected through a balanced arm. The sensitive wire is moved into the beam halo region by a stepper motor controlled translational stage. We study the feasibility of the vibrating wire for the transverse beam halo measurements in the low-energy front-end of the proton linac.

Phase transformation of 316L stainless steel from wire to fiber

International Nuclear Information System (INIS)

Shyr, Tien-Wei; Shie, Jing-Wen; Huang, Shih-Ju; Yang, Shun-Tung; Hwang, Weng-Sing

2010-01-01

In this work, quantitative crystalline phase analysis of 316L stainless steel from wire to fiber using a multi-pass cold drawing process was studied using the Rietveld whole XRD profile fitting technique. The different diameters of the fibers: 179, 112, 75, 50, 34, 20, and 8 μm, were produced from an as-received wire with a diameter of 190 μm. The crystalline phases were identified using MDI Jade 5.0 software. The volume fractions of crystalline phases were estimated using a Materials Analysis Using Diffraction software. XRD analysis revealed that the crystal structure of as-received wire is essentially a γ-austenite crystalline phase. The phase transformation occurred during the 316L stainless steel from wire to fiber. Three crystalline phases such as γ-austenite, α'-martensite, and sigma phase of the fine fiber were observed. A cold drawing accelerates the sigma phase precipitates, particularly during the heat treatment of the fiber.

Computer Tomography Scanners in Portugal (1990-2011

Directory of Open Access Journals (Sweden)

Ricardo Crispim

2014-06-01

Full Text Available The use of Computed Tomography (CT has increased every year since its introduction into medicine in 1972. Technological developments have made CT one of the most important imaging modalities in modern medicine. This importance is evidenced in the increasing demand and number of CT scanners installed in Portugal and worldwide. This review compiles the most recent national statistics from official publications on the number of CT scanners installed in Portugal and compares them with data available in international publications. We conclude that the number of CT scanners installed in Portugal exceeded the EU27 average by 61.5 % and the OECD average by 78.2 %, and that in 2011 there were 203 CT scanners installed in hospitals in Portugal, which equated to 19.23 CT scanners per million inhabitants.

Characterization of radiochromic films EBT3 by means of the scanner Vidar dosimetry Pro Red and Epson 10000-XL use; Caracterizacion de films radiocromicos EBT3 mediante el uso de scanner Vidar dosimetry Pro Red y Epson 10000-XL

Energy Technology Data Exchange (ETDEWEB)

Medina, L.; Garrigo, E.; Venencia, D.; Adrada, A.; Filipuzzi, M., E-mail: fisicamedina11@gmail.com [Instituto Privado de Radioterapia, Obispo Oro 423, X5000BFI Cordoba (Argentina)

2014-08-15

The Radiochromic film have become an attractive tool for verification of dose distributions in IMRT because these have high spatial resolution film, are near water equivalent and not require revealed, A critical aspect of the use of these film is used for digitizing scanner The purpose of this paper is to characterize EBT3 using two types of scanner. Were employed The Radiochromic film EBT3, was used photon beam 6 MV generated by a linear accelerator Siemens Primus, he films were irradiated at a dose range between 0 Gy a 9 Gy. The stabilization time after irradiation was 24 hours. The films were digitized with a scanner Epson 10000-XL y el VIDAR Dosimetry Pro Red. We used the software for construction of the calibration curve. The resolution of each dosimetry system was analyzed through the results of the spatial response function by analyzing a step pattern. The Epson scanner is most sensitive to the red channel. This is less than that obtained with the Vidar. The Vidar scanner spatial response profiles disturbs not opposed to Epson analyzed. The calibration curves for both dosimetry systems can be employed. However, the sensitivity and repeatability of the system is better than Red Vidar Epson 10000-XL. (author)

Neurosurgical operating computerized tomographic scanner system

International Nuclear Information System (INIS)

Okudera, Hiroshi; Sugita, Kenichiro; Kobayashi, Shigeaki; Kimishima, Sakae; Yoshida, Hisashi.

1988-01-01

A neurosurgical operating computerized tomography scanner system is presented. This system has been developed for obtaining intra- and postoperative CT images in the operating room. A TCT-300 scanner (manufactured by the Toshiba Co., Tokyo) is placed in the operating room. The realization of a true intraoperative CT image requires certain improvements in the CT scanner and operating table. To adjust the axis of the co-ordinates of the motor system of the MST-7000 microsurgical operating table (manufactured by the Mizuho Ika Co., Tokyo) to the CT scanner, we have designed an interface and a precise motor system so that the computer of the CT scanner can directly control the movement of the operating table. Furthermore, a new head-fixation system has been designed for producing artifact-free intraoperative CT images. The head-pins of the head-fixation system are made of carbon-fiber bars and titanium tips. A simulation study of the total system in the operating room with the CT scanner, operating table, and head holder using a skull model yielded a degree of error similar to that in the phantom testing of the original scanner. Three patients underwent resection of a glial tumor using this system. Intraoperative CT scans taken after dural opening showed a bulging of the cortex, a shift in the central structure, and a displacement of the cortical subarachnoid spaces under the influence of gravity. With a contrast medium the edge of the surrounding brain after resection was enhanced and the residual tumor mass was demonstrated clearly. This system makes it possible to obtain a noninvasive intraoperative image in a situation where structural shifts are taking place. (author)

Deriving stable multi-parametric MRI radiomic signatures in the presence of inter-scanner variations: survival prediction of glioblastoma via imaging pattern analysis and machine learning techniques

Science.gov (United States)

Rathore, Saima; Bakas, Spyridon; Akbari, Hamed; Shukla, Gaurav; Rozycki, Martin; Davatzikos, Christos

2018-02-01

There is mounting evidence that assessment of multi-parametric magnetic resonance imaging (mpMRI) profiles can noninvasively predict survival in many cancers, including glioblastoma. The clinical adoption of mpMRI as a prognostic biomarker, however, depends on its applicability in a multicenter setting, which is hampered by inter-scanner variations. This concept has not been addressed in existing studies. We developed a comprehensive set of within-patient normalized tumor features such as intensity profile, shape, volume, and tumor location, extracted from multicenter mpMRI of two large (npatients=353) cohorts, comprising the Hospital of the University of Pennsylvania (HUP, npatients=252, nscanners=3) and The Cancer Imaging Archive (TCIA, npatients=101, nscanners=8). Inter-scanner harmonization was conducted by normalizing the tumor intensity profile, with that of the contralateral healthy tissue. The extracted features were integrated by support vector machines to derive survival predictors. The predictors' generalizability was evaluated within each cohort, by two cross-validation configurations: i) pooled/scanner-agnostic, and ii) across scanners (training in multiple scanners and testing in one). The median survival in each configuration was used as a cut-off to divide patients in long- and short-survivors. Accuracy (ACC) for predicting long- versus short-survivors, for these configurations was ACCpooled=79.06% and ACCpooled=84.7%, ACCacross=73.55% and ACCacross=74.76%, in HUP and TCIA datasets, respectively. The hazard ratio at 95% confidence interval was 3.87 (2.87-5.20, P<0.001) and 6.65 (3.57-12.36, P<0.001) for HUP and TCIA datasets, respectively. Our findings suggest that adequate data normalization coupled with machine learning classification allows robust prediction of survival estimates on mpMRI acquired by multiple scanners.

Product development of Indian cargo scanner

International Nuclear Information System (INIS)

2017-01-01

A cargo scanner is required for nonintrusive screening of suspected cargo containers in trade, using high energy X-ray, to detect any mis-declarations, contraband goods concealment or hidden ammunition or explosives. The cargo scanners help authorities to process large number of suspected cargo with a high level of confidence with other additional benefit of faster clearance, minimised intrusive inspection and generating secured digital record of the process. BARC is in process of developing Indian Cargo Scanner with indigenous X-ray source. Proof of concept and conformance of the results to the international standards has been demonstrated in laboratory. Full scale equipment named as Portal scanner shall be demonstrated at Gamma field Trombay in year 2017. Subsequently the technology transfer may be done to a suitable Indian vendor

Detection of a buried wire with two resistively loaded wire antennas

NARCIS (Netherlands)

Vossen, S.H.J.A.; Tijhuis, A.G.; Lepelaars, E.S.A.M.; Zwamborn, A.P.M.

2002-01-01

The use of two identical straight thin-wire antennas for the detection of a buried wire is analyzed with the aid of numerical calculations. The buried wire is located below an interface between two homogeneous half-spaces. The detection setup, which is formed by a transmitting and a receiving wire,

wire chamber

CERN Multimedia

1985-01-01

Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

Wire chamber

CERN Multimedia

Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

wire chamber

CERN Multimedia

Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

Wire Array Photovoltaics

Science.gov (United States)

Turner-Evans, Dan

Over the past five years, the cost of solar panels has dropped drastically and, in concert, the number of installed modules has risen exponentially. However, solar electricity is still more than twice as expensive as electricity from a natural gas plant. Fortunately, wire array solar cells have emerged as a promising technology for further lowering the cost of solar. Si wire array solar cells are formed with a unique, low cost growth method and use 100 times less material than conventional Si cells. The wires can be embedded in a transparent, flexible polymer to create a free-standing array that can be rolled up for easy installation in a variety of form factors. Furthermore, by incorporating multijunctions into the wire morphology, higher efficiencies can be achieved while taking advantage of the unique defect relaxation pathways afforded by the 3D wire geometry. The work in this thesis shepherded Si wires from undoped arrays to flexible, functional large area devices and laid the groundwork for multijunction wire array cells. Fabrication techniques were developed to turn intrinsic Si wires into full p-n junctions and the wires were passivated with a-Si:H and a-SiNx:H. Single wire devices yielded open circuit voltages of 600 mV and efficiencies of 9%. The arrays were then embedded in a polymer and contacted with a transparent, flexible, Ni nanoparticle and Ag nanowire top contact. The contact connected >99% of the wires in parallel and yielded flexible, substrate free solar cells featuring hundreds of thousands of wires. Building on the success of the Si wire arrays, GaP was epitaxially grown on the material to create heterostructures for photoelectrochemistry. These cells were limited by low absorption in the GaP due to its indirect bandgap, and poor current collection due to a diffusion length of only 80 nm. However, GaAsP on SiGe offers a superior combination of materials, and wire architectures based on these semiconductors were investigated for multijunction

Beam profile measurement of ES-200 using secondary electron emission monitor

Directory of Open Access Journals (Sweden)

E Ebrahimi Basabi

2015-09-01

Full Text Available Up to now, different designs have been introduced for measurement beam profile accelerators. Secondary electron emission monitors (SEM are one of these devices which have been used for this purpose. In this work, a SEM has been constructed to measure beam profile of ES-200 accelerator, a proton electrostatic accelerator which is installed at SBU. Profile grid for both planes designed with 16 wires which are insulated relative to each other. The particles with maximum energy of 200 keV and maximum current of 400 μA are stopped in copper wires. Each of the wires has an individual current-to-voltage amplifier. With a multiplexer, the analogue values are transported to an ADC. The ADCs are read out by a microcontroller and finally profile of beam shows by a user interface program

Body scanners: are they dangerous for health?; Scanners corporels: dangereux pour la sante?

Energy Technology Data Exchange (ETDEWEB)

Anon.

2010-07-01

As there is a debate about the risk of cancer and of congenital malformation associated with the use of body scanners, notably in airports, this document recalls and comments the IAEA statement on this issue. According to a study performed by this international agency, the irradiation dose is very low. But the French IRSN is more prudent and recommends not to use X ray scanner, but to look for technologies which do not use ionizing radiation

49 CFR 236.74 - Protection of insulated wire; splice in underground wire.

Science.gov (United States)

2010-10-01

... underground wire. 236.74 Section 236.74 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING... wire; splice in underground wire. Insulated wire shall be protected from mechanical injury. The...

49 CFR 234.241 - Protection of insulated wire; splice in underground wire.

Science.gov (United States)

2010-10-01

... underground wire. 234.241 Section 234.241 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GRADE CROSSING SIGNAL SYSTEM SAFETY... of insulated wire; splice in underground wire. Insulated wire shall be protected from mechanical...

wire chamber

CERN Multimedia

Was used in ISR (Intersecting Storage Ring) split field magnet experiment. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

Compensation strategies for PET scanners with unconventional scanner geometry

CERN Document Server

Gundlich, B; Oehler, M

2006-01-01

The small animal PET scanner ClearPET®Neuro, developed at the Forschungszentrum Julich GmbH in cooperation with the Crystal Clear Collaboration (CERN), represents scanners with an unconventional geometry: due to axial and transaxial detector gaps ClearPet®Neuro delivers inhomogeneous sinograms with missing data. When filtered backprojection (FBP) or Fourier rebinning (FORE) are applied, strong geometrical artifacts appear in the images. In this contribution we present a method that takes the geometrical sensitivity into account and converts the measured sinograms into homogeneous and complete data. By this means artifactfree images are achieved using FBP or FORE. Besides an advantageous measurement setup that reduces inhomogeneities and data gaps in the sinograms, a modification of the measured sinograms is necessary. This modification includes two steps: a geometrical normalization and corrections for missing data. To normalize the measured sinograms, computed sinograms are used that describe the geometric...

Experience with a fuel rod enrichment scanner

International Nuclear Information System (INIS)

Kubik, R.N.; Pettus, W.G.

1975-01-01

This enrichment scanner views all fuel rods produced at B and W's Commercial Nuclear Fuel Plant. The scanner design is derived from the PAPAS System reported by R. A. Forster, H. D. Menlove, and their associates at Los Alamos. The spatial resolution of the system and smoothing of the data are discussed in detail. The cost-effectiveness of multi-detector versus single detector scanners of this general design is also discussed

PS wire chamber

CERN Multimedia

1970-01-01

A wire chamber used at CERN's Proton Synchrotron accelerator in the 1970s. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

New concepts and materials for the manufacturing of MR-compatible guide wires.

Science.gov (United States)

Brecher, Christian; Emonts, Michael; Brack, Alexander; Wasiak, Christian; Schütte, Adrian; Krämer, Nils; Bruhn, Robin

2014-04-01

This paper shows the development of a new magnetic resonance imaging (MRI)-compatible guide wire made from fiber-reinforced plastics. The basic material of the developed guide wire is manufactured using a specially developed micro-pullwinding technology, which allows the adjustment of tensile, bending, and torsional stiffness independent from each other. Additionally, the micro-pullwinding technology provides the possibility to vary the stiffness along the length of the guide wire in a continuous process. With the possibilities of this technology, the mechanical properties of the guide wire were precisely adjusted for the intended usage in MRI-guided interventions. The performance of the guide wire regarding the mechanical properties was investigated. It could be shown, that the mechanical properties could be changed independently from each other by varying the process parameters. Especially, the torsional stiffness could be significantly improved with only a minor influence on bending and tensile properties. The precise influence of the variation of the winding angle on the mechanical and geometrical properties has to be further investigated. The usability of the guide wire as well as its visibility in MRI was investigated by radiologists. With the micro-pullwinding technology, a continuous manufacturing technique for highly stressable, MRI-safe profiles is available and can be the trigger for a new class of medical devices.

Rail Track Detection and Modelling in Mobile Laser Scanner Data

Directory of Open Access Journals (Sweden)

S. Oude Elberink

2013-10-01

Full Text Available We present a method for detecting and modelling rails in mobile laser scanner data. The detection is based on the properties of the rail tracks and contact wires such as relative height, linearity and relative position with respect to other objects. Points classified as rail track are used in a 3D modelling algorithm. The modelling is done by first fitting a parametric model of a rail piece to the points along each track, and estimating the position and orientation parameters of each piece model. For each position and orientation parameter a smooth low-order Fourier curve is interpolated. Using all interpolated parameters a mesh model of the rail is reconstructed. The method is explained using two areas from a dataset acquired by a LYNX mobile mapping system in a mountainous area. Residuals between railway laser points and 3D models are in the range of 2 cm. It is concluded that a curve fitting algorithm is essential to reliably and accurately model the rail tracks by using the knowledge that railways are following a continuous and smooth path.

Wire bonding in microelectronics

CERN Document Server

Harman, George G

2010-01-01

Wire Bonding in Microelectronics, Third Edition, has been thoroughly revised to help you meet the challenges of today's small-scale and fine-pitch microelectronics. This authoritative guide covers every aspect of designing, manufacturing, and evaluating wire bonds engineered with cutting-edge techniques. In addition to gaining a full grasp of bonding technology, you'll learn how to create reliable bonds at exceedingly high yields, test wire bonds, solve common bonding problems, implement molecular cleaning methods, and much more. Coverage includes: Ultrasonic bonding systems and technologies, including high-frequency systems Bonding wire metallurgy and characteristics, including copper wire Wire bond testing Gold-aluminum intermetallic compounds and other interface reactions Gold and nickel-based bond pad plating materials and problems Cleaning to improve bondability and reliability Mechanical problems in wire bonding High-yield, fine-pitch, specialized-looping, soft-substrate, and extreme-temperature wire bo...

Multi-parameter CAMAC compatible ADC scanner

Energy Technology Data Exchange (ETDEWEB)

Midttun, G J; Ingebretsen, F [Oslo Univ. (Norway). Fysisk Inst.; Johnsen, P J [Norsk Data A.S., Box 163, Oekern, Oslo 5, Norway

1979-02-15

A fast ADC scanner for multi-parameter nuclear physics experiments is described. The scanner is based on a standard CAMAC crate, and data from several different experiments can be handled simultaneously through a direct memory access (DMA) channel. The implementation on a PDP-7 computer is outlined.

Online process monitoring at quasi-simultaneous laser transmission welding using a 3D-scanner with integrated pyrometer

Science.gov (United States)

Schmailzl, A.; Steger, S.; Dostalek, M.; Hierl, S.

2016-03-01

Quasi-simultaneous laser transmission welding is a well-known joining technique for thermoplastics and mainly used in the automotive as well as in the medical industry. For process control usually the so called set-path monitoring is used, where the weld is specified as "good" if the irradiation time is inside a defined confidence interval. However, the detection of small-sized gaps or thermal damaged zones is not possible with this technique. The analyzation of the weld seam temperature during welding offers the possibility to overcome this problem. In this approach a 3D-scanner is used instead of a scanner with flat-field optic. By using a pyrometer in combination with a 3D-scanner no color-corrected optic is needed in order to provide that laser- and detection-spot are concentric. Experimental studies on polyethylene T-joints have shown that the quality of the signal is adequate, despite the use of an optical setup with a long working distance and a small optical aperture. The effects on temperature are studied for defects like a gap in the joining zone. Therefore a notch was milled into the absorbent polymer. In case of producing housings for electronic parts the effect of an electrical wire between the joining partners is also investigated. Both defects can be identified by a local temperature deviation even at a feed rate of four meters per second. Furthermore a strategy for signal-processing is demonstrated. By this, remaining defects can be identified. Consequently an online detection of local defects is possible, which makes a dynamic process control feasible.

Scintillation scanner

International Nuclear Information System (INIS)

Mehrbrodt, A.W.; Mog, W.F.; Brunnett, C.J.

1977-01-01

A scintillation scanner having a visual image producing means coupled through a lost motion connection to the boom which supports the scintillation detector is described. The lost motion connection is adjustable to compensate for such delays as may occur between sensing and recording scintillations. 13 claims, 5 figures

Radiographic scanners and shutter mechanisms in CT scanners

International Nuclear Information System (INIS)

Braden, A.B.; Kuwik, J.J.; Taylor, S.K.; Covic, J.

1981-01-01

This patent claim relates especially to the design of a shutter mechanism in a CT scanner having a rotatable source of radiation and a series of stationary radiation detectors coplanar with the path of the source and spaced about the axis of rotation of the source, and only partially encircling the path of the source. (U.K.)

A Cost Effective Multi-Spectral Scanner for Natural Gas Detection

Energy Technology Data Exchange (ETDEWEB)

Yudaya Sivathanu; Jongmook Lim; Vinoo Narayanan; Seonghyeon Park

2005-12-07

The objective of this project is to design, fabricate and demonstrate a cost effective, multi-spectral scanner for natural gas leak detection in transmission and distribution pipelines. During the first year of the project, a laboratory version of the multi-spectral scanner was designed, fabricated, and tested at EnUrga Inc. The multi-spectral scanner was also evaluated using a blind Department of Energy study at the Rocky Mountain Oilfield Testing Center. The performance of the scanner was inconsistent during the blind study. However, most of the leaks were outside the view of the multi-spectral scanner that was developed during the first year of the project. Therefore, a definite evaluation of the capability of the scanner was not obtained. Despite the results, sufficient number of plumes was detected fully confirming the feasibility of the multi-spectral scanner. During the second year, the optical design of the scanner was changed to improve the sensitivity of the system. Laboratory tests show that the system can reliably detect small leaks (20 SCFH) at 30 to 50 feet. A prototype scanner was built and evaluated during the second year of the project. Only laboratory evaluations were completed during the second year. The laboratory evaluations show the feasibility of using the scanner to determine natural gas pipeline leaks. Further field evaluations and optimization of the scanner are required before commercialization of the scanner can be initiated.

Base Information Transport Infrastructure Wired (BITI Wired)

Science.gov (United States)

2016-03-01

2016 Major Automated Information System Annual Report Base Information Transport Infrastructure Wired (BITI Wired) Defense Acquisition Management...Combat Information Transport System program was restructured into two pre-Major Automated Information System (pre-MAIS) components: Information...Major Automated Information System MAIS OE - MAIS Original Estimate MAR – MAIS Annual Report MDA - Milestone Decision Authority MDD - Materiel

Load-Deflection and Friction Properties of PEEK Wires as Alternative Orthodontic Wires.

Science.gov (United States)

Tada, Yoshifumi; Hayakawa, Tohru; Nakamura, Yoshiki

2017-08-09

Polyetheretherketone (PEEK) is now attracting attention as an alternative to metal alloys in the dental field. In the present study, we evaluated the load-deflection characteristics of PEEK wires in addition to their frictional properties. Three types of PEEK wires are used: two sizes of rectangular shape, 0.016 × 0.022 in² and 0.019 × 0.025 in² (19-25PEEK), and rounded shape, diameter 0.016 in (16PEEK). As a control, Ni-Ti orthodontic wire, diameter 0.016 in, was used. The three-point bending properties were evaluated in a modified three-point bending system for orthodontics. The static friction between the orthodontic wire and the bracket was also measured. The load-deflection curves were similar among Ni-Ti and PEEK wires, except for 16PEEK with slot-lid ligation. The bending force of 19-25PEEK wire was comparable with that of Ni-Ti wire. 19-25PEEK showed the highest load at the deflection of 1500 μm ( p 0.05). No significant difference was seen in static friction between all three PEEK wires and Ni-Ti wire ( p > 0.05). It is suggested that 19-25PEEK will be applicable for orthodontic treatment with the use of slot-lid ligation.

Imaging system models for small-bore DOI-PET scanners

International Nuclear Information System (INIS)

Takahashi, Hisashi; Kobayashi, Tetsuya; Yamaya, Taiga; Murayama, Hideo; Kitamura, Keishi; Hasegawa, Tomoyuki; Suga, Mikio

2006-01-01

Depth-of-interaction (DOI) information, which improves resolution uniformity in the field of view (FOV), is expected to lead to high-sensitivity PET scanners with small-bore detector rings. We are developing small-bore PET scanners with DOI detectors arranged in hexagonal or overlapped tetragonal patterns for small animal imaging or mammography. It is necessary to optimize the imaging system model because these scanners exhibit irregular detector sampling. In this work, we compared two imaging system models: (a) a parallel sub-LOR model in which the detector response functions (DRFs) are assumed to be uniform along the line of responses (LORs) and (b) a sub-crystal model in which each crystal is divided into a set of smaller volumes. These two models were applied to the overlapped tetragonal scanner (FOV 38.1 mm in diameter) and the hexagonal scanner (FOV 85.2 mm in diameter) simulated by GATE. We showed that the resolution non-uniformity of system model (b) was improved by 40% compared with that of system model (a) in the overlapped tetragonal scanner and that the resolution non-uniformity of system model (a) was improved by 18% compared with that of system model (b) in the hexagonal scanner. These results indicate that system model (b) should be applied to the overlapped tetragonal scanner and system model (a) should be applied to the hexagonal scanner. (author)

Copper wire bonding

CERN Document Server

Chauhan, Preeti S; Zhong, ZhaoWei; Pecht, Michael G

2014-01-01

This critical volume provides an in-depth presentation of copper wire bonding technologies, processes and equipment, along with the economic benefits and risks.  Due to the increasing cost of materials used to make electronic components, the electronics industry has been rapidly moving from high cost gold to significantly lower cost copper as a wire bonding material.  However, copper wire bonding has several process and reliability concerns due to its material properties.  Copper Wire Bonding book lays out the challenges involved in replacing gold with copper as a wire bond material, and includes the bonding process changes—bond force, electric flame off, current and ultrasonic energy optimization, and bonding tools and equipment changes for first and second bond formation.  In addition, the bond–pad metallurgies and the use of bare and palladium-coated copper wires on aluminum are presented, and gold, nickel and palladium surface finishes are discussed.  The book also discusses best practices and re...

Scanner OPC signatures: automatic vendor-to-vendor OPE matching

Science.gov (United States)

Renwick, Stephen P.

2009-03-01

As 193nm lithography continues to be stretched and the k1 factor decreases, optical proximity correction (OPC) has become a vital part of the lithographer's tool kit. Unfortunately, as is now well known, the design variations of lithographic scanners from different vendors cause them to have slightly different optical-proximity effect (OPE) behavior, meaning that they print features through pitch in distinct ways. This in turn means that their response to OPC is not the same, and that an OPC solution designed for a scanner from Company 1 may or may not work properly on a scanner from Company 2. Since OPC is not inexpensive, that causes trouble for chipmakers using more than one brand of scanner. Clearly a scanner-matching procedure is needed to meet this challenge. Previously, automatic matching has only been reported for scanners of different tool generations from the same manufacturer. In contrast, scanners from different companies have been matched using expert tuning and adjustment techniques, frequently requiring laborious test exposures. Automatic matching between scanners from Company 1 and Company 2 has remained an unsettled problem. We have recently solved this problem and introduce a novel method to perform the automatic matching. The success in meeting this challenge required three enabling factors. First, we recognized the strongest drivers of OPE mismatch and are thereby able to reduce the information needed about a tool from another supplier to that information readily available from all modern scanners. Second, we developed a means of reliably identifying the scanners' optical signatures, minimizing dependence on process parameters that can cloud the issue. Third, we carefully employed standard statistical techniques, checking for robustness of the algorithms used and maximizing efficiency. The result is an automatic software system that can predict an OPC matching solution for scanners from different suppliers without requiring expert intervention.

Temperature dependence of APD-based PET scanners

International Nuclear Information System (INIS)

Keereman, Vincent; Van Holen, Roel; Vandenberghe, Stefaan; Vanhove, Christian

2013-01-01

Purpose: Solid state detectors such as avalanche photodiodes (APDs) are increasingly being used in PET detectors. One of the disadvantages of APDs is the strong decrease of their gain factor with increasing ambient temperature. The light yield of most scintillation crystals also decreases when ambient temperature is increased. Both effects lead to considerable temperature dependence of the performance of APD-based PET scanners. In this paper, the authors propose a model for this dependence and the performance of the LabPET8 APD-based small animal PET scanner is evaluated at different temperatures.Methods: The model proposes that the effect of increasing temperature on the energy histogram of an APD-based PET scanner is a compression of the histogram along the energy axis. The energy histogram of the LabPET system was acquired at 21 °C and 25 °C to verify the validity of this model. Using the proposed model, the effect of temperature on system sensitivity was simulated for different detector temperature coefficients and temperatures. Subsequently, the effect of short term and long term temperature changes on the peak sensitivity of the LabPET system was measured. The axial sensitivity profile was measured at 21 °C and 24 °C following the NEMA NU 4-2008 standard. System spatial resolution was also evaluated. Furthermore, scatter fraction, count losses and random coincidences were evaluated at different temperatures. Image quality was also investigated.Results: As predicted by the model, the photopeak energy at 25 °C is lower than at 21 °C with a shift of approximately 6% per °C. Simulations showed that this results in an approximately linear decrease of sensitivity when temperature is increased from 21 °C to 24 °C and energy thresholds are constant. Experimental evaluation of the peak sensitivity at different temperatures showed a strong linear correlation for short term (2.32 kcps/MBq/°C = 12%/°C, R = −0.95) and long term (1.92 kcps/MBq/°C = 10%/�

Fatigue testing of controlled memory wire nickel-titanium rotary instruments.

Science.gov (United States)

Shen, Ya; Qian, Wei; Abtin, Houman; Gao, Yuan; Haapasalo, Markus

2011-07-01

To improve the fracture resistance of nickel-titanium (NiTi) files, manufacturers have introduced new alloys to manufacture NiTi files and developed new manufacturing processes. This study was aimed to examine the fatigue behavior of NiTi instruments from a novel controlled memory NiTi wire (CM Wire). Instruments of ProFile, Typhoon (TYP), Typhoon CM (TYP CM), DS-SS0250425NEYY (NEYY), and DS-SS0250425NEYY CM (NEYY CM) (DS Dental, Johnson City, TN) all size 25/.04 were subjected to rotational bending at the curvature of 35° and 45° in air at the temperature of 23° ± 2°C, and the number of revolutions to fracture (N(f)) was recorded. The fracture surface of all fragments was examined by a scanning electron microscope. The crack-initiation sites, the percentage of dimple area to the whole fracture cross-section, and the surface strain amplitude (ε(a)) were noted. The new alloy yielded an improvement of over three to eight times in N(f) of CM files than that of conventional NiTi files (P wire (58%-100%) had one crack origin. The values of the fraction area occupied by the dimple region were significantly smaller on CM NiTi instruments compared with conventional NiTi instruments (P wire at both curvatures (P Wire had a significantly higher N(f) and lower surface strain amplitude than the conventional NiTi wire files with identical design. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

MEMS temperature scanner: principles, advances, and applications

Science.gov (United States)

Otto, Thomas; Saupe, Ray; Stock, Volker; Gessner, Thomas

2010-02-01

Contactless measurement of temperatures has gained enormous significance in many application fields, ranging from climate protection over quality control to object recognition in public places or military objects. Thereby measurement of linear or spatially temperature distribution is often necessary. For this purposes mostly thermographic cameras or motor driven temperature scanners are used today. Both are relatively expensive and the motor drive devices are limited regarding to the scanning rate additionally. An economic alternative are temperature scanner devices based on micro mirrors. The micro mirror, attached in a simple optical setup, reflects the emitted radiation from the observed heat onto an adapted detector. A line scan of the target object is obtained by periodic deflection of the micro scanner. Planar temperature distribution will be achieved by perpendicularly moving the target object or the scanner device. Using Planck radiation law the temperature of the object is calculated. The device can be adapted to different temperature ranges and resolution by using different detectors - cooled or uncooled - and parameterized scanner parameters. With the basic configuration 40 spatially distributed measuring points can be determined with temperatures in a range from 350°C - 1000°C. The achieved miniaturization of such scanners permits the employment in complex plants with high building density or in direct proximity to the measuring point. The price advantage enables a lot of applications, especially new application in the low-price market segment This paper shows principle, setup and application of a temperature measurement system based on micro scanners working in the near infrared range. Packaging issues and measurement results will be discussed as well.

Measurement of weak electric currents in copper wire phantoms using MRI: influence of susceptibility enhancement.

Science.gov (United States)

Huang, Ruiwang; Posnansky, Oleg; Celik, Abdullah; Oros-Peusquens, Ana-Maria; Ermer, Veronika; Irkens, Marco; Wegener, H-Peter; Shah, N Jon

2006-08-01

The use of magnetic resonance imaging (MRI)-based methods for the direct detection of neuronal currents is a topic of intense investigation. Much experimental work has been carried out with the express aim of establishing detection thresholds and sensitivity to flowing currents. However, in most of these experiments, magnetic susceptibility enhancement was ignored. In this work, we present results that show the influence of a susceptibility artefact on the detection threshold and sensitivity. For this purpose, a novel phantom, consisting of a water-filled cylinder with two wires of different materials connected in series, was constructed. Magnitude MR images were acquired from a single slice using a gradient-echo echo planar imaging (EPI) sequence. The data show that the time course of the detected MR signal magnitude correlates very well with the waveform of the input current. The effect of the susceptibility artefacts arising from the two different wires was examined by comparing the magnitudes of the MR signals at different voxel locations. Our results indicate the following: (1) MR signal enhancement arising from the magnetic susceptibility effect influences the detection sensitivity of weak current; (2) the detection threshold and sensitivity are phantom-wire dependent; (3) sub-mu A electric current detection in a phantom is possible on a 1.5-T MR scanner in the presence of susceptibility enhancement.

Nogle muligheder i scanner data

DEFF Research Database (Denmark)

Juhl, Hans Jørn

2000-01-01

I artiklen gives en diskussion af en række af de muligheder for effektivisering af marketingaktiviteter, der er til stede for såvel mærkevareudbyder som detaillist, ved udnyttelse af information fra scanner data......I artiklen gives en diskussion af en række af de muligheder for effektivisering af marketingaktiviteter, der er til stede for såvel mærkevareudbyder som detaillist, ved udnyttelse af information fra scanner data...

The number and distribution of computerised tomography scanners in Turkey

International Nuclear Information System (INIS)

Semin, S.; Amato, Z.

1999-01-01

The goal of this study was to investigate the number and distribution of CT scanners in Turkey. Our results show 173 CT scanners in Turkey in 1994, which equals 2.9 scanners per million people. All of the scanners are located in 45 cities, where 81 % of the population resides. The other 31 cities in Turkey have no scanners. Of the 173 scanners, 103 (59.6 %) are owned by the private sector and the other 70 are owned by the public sector. Of Turkey's CT scanners, 49.2 % are located in private health centres, 21.9 % in university hospitals, 16.7 % in Ministry of Health (MOH) hospitals, 10.4 % in private hospitals and 1.8 % in social security hospitals. (orig.)

Evaluation of mechanical properties in metal wire mesh supported selective catalytic reduction (SCR) catalyst structures

Science.gov (United States)

Rajath, S.; Siddaraju, C.; Nandakishora, Y.; Roy, Sukumar

2018-04-01

The objective of this research is to evaluate certain specific mechanical properties of certain stainless steel wire mesh supported Selective catalytic reduction catalysts structures wherein the physical properties of the metal wire mesh and also its surface treatments played vital role thereby influencing the mechanical properties. As the adhesion between the stainless steel wire mesh and the catalyst material determines the bond strength and the erosion resistance of catalyst structures, surface modifications of the metal- wire mesh structure in order to facilitate the interface bonding is therefore very important to realize enhanced level of mechanical properties. One way to enhance such adhesion properties, the stainless steel wire mesh is treated with the various acids, i.e., chromic acid, phosphoric acid including certain mineral acids and combination of all those in various molar ratios that could generate surface active groups on metal surface that promotes good interface structure between the metal- wire mesh and metal oxide-based catalyst material and then the stainless steel wire mesh is dipped in the glass powder slurry containing some amount of organic binder. As a result of which the said catalyst material adheres to the metal-wire mesh surface more effectively that improves the erosion profile of supported catalysts structure including bond strength.

3D whole body scanners revisited

NARCIS (Netherlands)

Daanen, H.A.M.; Haar, F.B. ter

2013-01-01

An overview of whole body scanners in 1998 (H.A.M. Daanen, G.J. Van De Water. Whole body scanners, Displays 19 (1998) 111-120) shortly after they emerged to the market revealed that the systems were bulky, slow, expensive and low in resolution. This update shows that new developments in sensing and

Theory of wire number scaling in wire-array Z pinches

International Nuclear Information System (INIS)

Desjarlais, M.P.; Marder, B.M.

1999-01-01

Pulsed-power-driven Z pinches, produced by imploding cylindrical arrays of many wires, have generated very high x-ray radiation powers (>200 TW) and energies (2 MJ). Experiments have revealed a steady improvement in Z-pinch performance with increasing wire number at fixed total mass and array radius. The dominant mechanism acting to limit the performance of these devices is believed to be the Rayleigh-Taylor instability which broadens the radially imploding plasma sheath and consequently reduces the peak radiation power. A model is presented which describes an amplification over the two-dimensional Rayleigh-Taylor growth rate brought about by kink-like forces on the individual wires. This amplification factor goes to zero as the number of wires approaches infinity. This model gives results which are in good agreement with the experimental data and provides a scaling for wire-array Z pinches. copyright 1999 American Institute of Physics

Methods for CT automatic exposure control protocol translation between scanner platforms.

Science.gov (United States)

McKenney, Sarah E; Seibert, J Anthony; Lamba, Ramit; Boone, John M

2014-03-01

An imaging facility with a diverse fleet of CT scanners faces considerable challenges when propagating CT protocols with consistent image quality and patient dose across scanner makes and models. Although some protocol parameters can comfortably remain constant among scanners (eg, tube voltage, gantry rotation time), the automatic exposure control (AEC) parameter, which selects the overall mA level during tube current modulation, is difficult to match among scanners, especially from different CT manufacturers. Objective methods for converting tube current modulation protocols among CT scanners were developed. Three CT scanners were investigated, a GE LightSpeed 16 scanner, a GE VCT scanner, and a Siemens Definition AS+ scanner. Translation of the AEC parameters such as noise index and quality reference mAs across CT scanners was specifically investigated. A variable-diameter poly(methyl methacrylate) phantom was imaged on the 3 scanners using a range of AEC parameters for each scanner. The phantom consisted of 5 cylindrical sections with diameters of 13, 16, 20, 25, and 32 cm. The protocol translation scheme was based on matching either the volumetric CT dose index or image noise (in Hounsfield units) between two different CT scanners. A series of analytic fit functions, corresponding to different patient sizes (phantom diameters), were developed from the measured CT data. These functions relate the AEC metric of the reference scanner, the GE LightSpeed 16 in this case, to the AEC metric of a secondary scanner. When translating protocols between different models of CT scanners (from the GE LightSpeed 16 reference scanner to the GE VCT system), the translation functions were linear. However, a power-law function was necessary to convert the AEC functions of the GE LightSpeed 16 reference scanner to the Siemens Definition AS+ secondary scanner, because of differences in the AEC functionality designed by these two companies. Protocol translation on the basis of

Dual wire welding torch and method

Science.gov (United States)

Diez, Fernando Martinez; Stump, Kevin S.; Ludewig, Howard W.; Kilty, Alan L.; Robinson, Matthew M.; Egland, Keith M.

2009-04-28

A welding torch includes a nozzle with a first welding wire guide configured to orient a first welding wire in a first welding wire orientation, and a second welding wire guide configured to orient a second welding wire in a second welding wire orientation that is non-coplanar and divergent with respect to the first welding wire orientation. A method of welding includes moving a welding torch with respect to a workpiece joint to be welded. During moving the welding torch, a first welding wire is fed through a first welding wire guide defining a first welding wire orientation and a second welding wire is fed through a second welding wire guide defining a second welding wire orientation that is divergent and non-coplanar with respect to the first welding wire orientation.

THERMO-MECHANICALLY PROCESSED ROLLED WIRE FOR HIGH-STRENGTH ON-BOARD WIRE

Directory of Open Access Journals (Sweden)

V. A. Lutsenko

2011-01-01

Full Text Available It is shown that at twisting of wire of diameter 1,83 mm, produced by direct wire drawing of thermomechanically processed rolled wire of diameter 5,5 mm of steel 90, metal stratification is completely eliminated at decrease of carbon, manganese and an additional alloying of chrome.

AUTOMATED CONTROL AND REAL-TIME DATA PROCESSING OF WIRE SCANNER/HALO SCRAPER MEASUREMENTS

International Nuclear Information System (INIS)

Day, L.A.; Gilpatrick, J.D.

2001-01-01

The Low-Energy Demonstration Accelerator (LEDA), assembled and operating at Los Alamos National Laboratory, provides the platform for obtaining measurements of high-power proton beam-halo formation. Control system software and hardware have been integrated and customized to enable the production of real-time beam-halo profiles. The Experimental Physics and Industrial Control System (EPICS) hosted on a VXI platform, Interactive Data Language (IDL) programs hosted on UNIX platforms, and LabVIEW (LV) Virtual Instruments hosted on a PC platform have been integrated and customized to provide real-time, synchronous motor control, data acquisition, and data analysis of data acquired through specialized DSP instrumentation. These modules communicate through EPICS Channel Access (CA) communication protocol extensions to control and manage execution flow ensuring synchronous data acquisition and real-time processing of measurement data. This paper describes the software integration and management scheme implemented to produce these real-time beam profiles

One century of Kirschner wires and Kirschner wire insertion techniques : A historical review

NARCIS (Netherlands)

Franssen, Bas B. G. M.; Schuurman, Arnold H.; Van der Molen, Aebele Mink; Kon, Moshe

A century ago, in 1909, Martin Kirschner (1879-942) introduced a smooth pin, presently known as the Kirschner wire (K-wire). The K-wire was initiallly used for skeletal traction and is now currently used for many different goals. The development of the K-wire and its insertion devices were mainly

Comparison of Epson scanner quality for radiochromic film evaluation.

Science.gov (United States)

Alnawaf, Hani; Yu, Peter K N; Butson, Martin

2012-09-06

Epson Desktop scanners have been quoted as devices which match the characteristics required for the evaluation of radiation dose exposure by radiochromic films. Specifically, models such as the 10000XL have been used successfully for image analysis and are recommended by ISP for dosimetry purposes. This note investigates and compares the scanner characteristics of three Epson desktop scanner models including the Epson 10000XL, V700, and V330. Both of the latter are substantially cheaper models capable of A4 scanning. As the price variation between the V330 and the 10000XL is 20-fold (based on Australian recommended retail price), cost savings by using the cheaper scanners may be warranted based on results. By a direct comparison of scanner uniformity and reproducibility we can evaluate the accuracy of these scanners for radiochromic film dosimetry. Results have shown that all three scanners can produce adequate scanner uniformity and reproducibility, with the inexpensive V330 producing a standard deviation variation across its landscape direction of 0.7% and 1.2% in the portrait direction (reflection mode). This is compared to the V700 in reflection mode of 0.25% and 0.5% for landscape and portrait directions, respectively, and 0.5% and 0.8% for the 10000XL. In transmission mode, the V700 is comparable in reproducibility to the 10000XL for portrait and landscape mode, whilst the V330 is only capable of scanning in the landscape direction and produces a standard deviation in this direction of 1.0% compared to 0.6% (V700) and 0.25% (10000XL). Results have shown that the V700 and 10000XL are comparable scanners in quality and accuracy with the 10000XL obviously capable of imaging over an A3 area as opposed to an A4 area for the V700. The V330 scanner produced slightly lower accuracy and quality with uncertainties approximately twice as much as the other scanners. However, the results show that the V330 is still an adequate scanner and could be used for radiation

Calibration of EBT2 film by the PDD method with scanner non-uniformity correction.

Science.gov (United States)

Chang, Liyun; Chui, Chen-Shou; Ding, Hueisch-Jy; Hwang, Ing-Ming; Ho, Sheng-Yow

2012-09-21

The EBT2 film together with a flatbed scanner is a convenient dosimetry QA tool for verification of clinical radiotherapy treatments. However, it suffers from a relatively high degree of uncertainty and a tedious film calibration process for every new lot of films, including cutting the films into several small pieces, exposing with different doses, restoring them back and selecting the proper region of interest (ROI) for each piece for curve fitting. In this work, we present a percentage depth dose (PDD) method that can accurately calibrate the EBT2 film together with the scanner non-uniformity correction and provide an easy way to perform film dosimetry. All films were scanned before and after the irradiation in one of the two homemade 2 mm thick acrylic frames (one portrait and the other landscape), which was located at a fixed position on the scan bed of an Epson 10 000XL scanner. After the pre-irradiated scan, the film was placed parallel to the beam central axis and sandwiched between six polystyrene plates (5 cm thick each), followed by irradiation of a 20 × 20 cm² 6 MV photon beam. Two different beams on times were used on two different films to deliver a dose to the film ranging from 32 to 320 cGy. After the post-irradiated scan, the net optical densities for a total of 235 points on the beam central axis on the films were auto-extracted and compared with the corresponding depth doses that were calculated through the measurement of a 0.6 cc farmer chamber and the related PDD table to perform the curve fitting. The portrait film location was selected for routine calibration, since the central beam axis on the film is parallel to the scanning direction, where non-uniformity correction is not needed (Ferreira et al 2009 Phys. Med. Biol. 54 1073-85). To perform the scanner non-uniformity calibration, the cross-beam profiles of the film were analysed by referencing the measured profiles from a Profiler™. Finally, to verify our method, the films were

Calibration of EBT2 film by the PDD method with scanner non-uniformity correction

International Nuclear Information System (INIS)

Chang Liyun; Ding, Hueisch-Jy; Chui, Chen-Shou; Hwang, Ing-Ming; Ho, Sheng-Yow

2012-01-01

The EBT2 film together with a flatbed scanner is a convenient dosimetry QA tool for verification of clinical radiotherapy treatments. However, it suffers from a relatively high degree of uncertainty and a tedious film calibration process for every new lot of films, including cutting the films into several small pieces, exposing with different doses, restoring them back and selecting the proper region of interest (ROI) for each piece for curve fitting. In this work, we present a percentage depth dose (PDD) method that can accurately calibrate the EBT2 film together with the scanner non-uniformity correction and provide an easy way to perform film dosimetry. All films were scanned before and after the irradiation in one of the two homemade 2 mm thick acrylic frames (one portrait and the other landscape), which was located at a fixed position on the scan bed of an Epson 10 000XL scanner. After the pre-irradiated scan, the film was placed parallel to the beam central axis and sandwiched between six polystyrene plates (5 cm thick each), followed by irradiation of a 20 × 20 cm 2 6 MV photon beam. Two different beams on times were used on two different films to deliver a dose to the film ranging from 32 to 320 cGy. After the post-irradiated scan, the net optical densities for a total of 235 points on the beam central axis on the films were auto-extracted and compared with the corresponding depth doses that were calculated through the measurement of a 0.6 cc farmer chamber and the related PDD table to perform the curve fitting. The portrait film location was selected for routine calibration, since the central beam axis on the film is parallel to the scanning direction, where non-uniformity correction is not needed (Ferreira et al 2009 Phys. Med. Biol. 54 1073–85). To perform the scanner non-uniformity calibration, the cross-beam profiles of the film were analysed by referencing the measured profiles from a Profiler™. Finally, to verify our method, the films were

Restoration of Hyperspectral Push-Broom Scanner Data

DEFF Research Database (Denmark)

Larsen, Rasmus; Nielsen, Allan Aasbjerg; Conradsen, Knut

1997-01-01

Several effects combine to distort the multispectral data that are obtained from push-broom scanners. We develop an algorithm for restoration of such data, illustrated on images from the ROSIS scanner. In push-broom scanners variation between elements in the detector array results in a strong...... back into the original spectral space results in noise corrected variables. The noise components will now have been removed from the entire original data set by working on a smaller set of noise contaminated transformed variables only. The application of the above techniques results in a dramatic...

Characterization of radiochromic films EBT3 by means of the scanner Vidar dosimetry Pro Red and Epson 10000-XL use

International Nuclear Information System (INIS)

Medina, L.; Garrigo, E.; Venencia, D.; Adrada, A.; Filipuzzi, M.

2014-08-01

The Radiochromic film have become an attractive tool for verification of dose distributions in IMRT because these have high spatial resolution film, are near water equivalent and not require revealed, A critical aspect of the use of these film is used for digitizing scanner The purpose of this paper is to characterize EBT3 using two types of scanner. Were employed The Radiochromic film EBT3, was used photon beam 6 MV generated by a linear accelerator Siemens Primus, he films were irradiated at a dose range between 0 Gy a 9 Gy. The stabilization time after irradiation was 24 hours. The films were digitized with a scanner Epson 10000-XL y el VIDAR Dosimetry Pro Red. We used the software for construction of the calibration curve. The resolution of each dosimetry system was analyzed through the results of the spatial response function by analyzing a step pattern. The Epson scanner is most sensitive to the red channel. This is less than that obtained with the Vidar. The Vidar scanner spatial response profiles disturbs not opposed to Epson analyzed. The calibration curves for both dosimetry systems can be employed. However, the sensitivity and repeatability of the system is better than Red Vidar Epson 10000-XL. (author)

Evaluation of surface roughness of orthodontic wires by means of atomic force microscopy.

Science.gov (United States)

D'Antò, Vincenzo; Rongo, Roberto; Ametrano, Gianluca; Spagnuolo, Gianrico; Manzo, Paolo; Martina, Roberto; Paduano, Sergio; Valletta, Rosa

2012-09-01

To compare the surface roughness of different orthodontic archwires. Four nickel-titanium wires (Sentalloy(®), Sentalloy(®) High Aesthetic, Titanium Memory ThermaTi Lite(®), and Titanium Memory Esthetic(®)), three β-titanium wires (TMA(®), Colored TMA(®), and Beta Titanium(®)), and one stainless-steel wire (Stainless Steel(®)) were considered for this study. Three samples for each wire were analyzed by atomic force microscopy (AFM). Three-dimensional images were processed using Gwiddion software, and the roughness average (Ra), the root mean square (Rms), and the maximum height (Mh) values of the scanned surface profile were recorded. Statistical analysis was performed by one-way analysis of variance (ANOVA) followed by Tukey's post hoc test (P Sentalloy High Aesthetic was the roughest (Ra  =  133.5 ± 10.8; Rms  =  165.8 ± 9.8; Mh  =  949.6 ± 192.1) of the archwires. The surface quality of the wires investigated differed significantly. Ion implantation effectively reduced the roughness of TMA. Moreover, Teflon(®)-coated Titanium Memory Esthetic was less rough than was ion-implanted Sentalloy High Aesthetic.

Reliability Criteria for Thick Bonding Wire.

Science.gov (United States)

Dagdelen, Turker; Abdel-Rahman, Eihab; Yavuz, Mustafa

2018-04-17

Bonding wire is one of the main interconnection techniques. Thick bonding wire is widely used in power modules and other high power applications. This study examined the case for extending the use of traditional thin wire reliability criteria, namely wire flexure and aspect ratio, to thick wires. Eleven aluminum (Al) and aluminum coated copper (CucorAl) wire samples with diameter 300 μm were tested experimentally. The wire response was measured using a novel non-contact method. High fidelity FEM models of the wire were developed and validated. We found that wire flexure is not correlated to its stress state or fatigue life. On the other hand, aspect ratio is a consistent criterion of thick wire fatigue life. Increasing the wire aspect ratio lowers its critical stress and increases its fatigue life. Moreover, we found that CucorAl wire has superior performance and longer fatigue life than Al wire.

Reliability Criteria for Thick Bonding Wire

Science.gov (United States)

Yavuz, Mustafa

2018-01-01

Bonding wire is one of the main interconnection techniques. Thick bonding wire is widely used in power modules and other high power applications. This study examined the case for extending the use of traditional thin wire reliability criteria, namely wire flexure and aspect ratio, to thick wires. Eleven aluminum (Al) and aluminum coated copper (CucorAl) wire samples with diameter 300 μm were tested experimentally. The wire response was measured using a novel non-contact method. High fidelity FEM models of the wire were developed and validated. We found that wire flexure is not correlated to its stress state or fatigue life. On the other hand, aspect ratio is a consistent criterion of thick wire fatigue life. Increasing the wire aspect ratio lowers its critical stress and increases its fatigue life. Moreover, we found that CucorAl wire has superior performance and longer fatigue life than Al wire. PMID:29673194

Influence and applicability of wire-mesh sensor to acquire two phase flow dynamics

International Nuclear Information System (INIS)

Kanai, Taizo; Furuya, Masahiro; Arai, Takahiro; Shirakawa, Kenetsu

2011-01-01

Wire-mesh sensors (WMS) are able to measure void distributions and velocity profile at high speed. Immersing the wire-mesh affects the structure of two-phase flow. Experiments were performed for single rising air bubble in a vertical pipe of i.d. 50 mm and 224 mm at water velocities ranging from 0.05 to 0.52 m/s and 0.42 to 0.83 m/s. Distortion of a relatively large bubble with the wire-mesh was small in the water velocity over 0.25 m/s and confirmed by cross-correlation analysis as well. Bubble rising velocity acquired by WMS is in good agreement with that estimated high-speed camera in the experimental range. WMS has applicability to acquire two phase flow dynamics in the water velocity over 0.25 m/s. (author)

21 CFR 882.1925 - Ultrasonic scanner calibration test block.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic scanner calibration test block. 882... Ultrasonic scanner calibration test block. (a) Identification. An ultrasonic scanner calibration test block is a block of material with known properties used to calibrate ultrasonic scanning devices (e.g., the...

Reliability Criteria for Thick Bonding Wire

Directory of Open Access Journals (Sweden)

Turker Dagdelen

2018-04-01

Full Text Available Bonding wire is one of the main interconnection techniques. Thick bonding wire is widely used in power modules and other high power applications. This study examined the case for extending the use of traditional thin wire reliability criteria, namely wire flexure and aspect ratio, to thick wires. Eleven aluminum (Al and aluminum coated copper (CucorAl wire samples with diameter 300 μm were tested experimentally. The wire response was measured using a novel non-contact method. High fidelity FEM models of the wire were developed and validated. We found that wire flexure is not correlated to its stress state or fatigue life. On the other hand, aspect ratio is a consistent criterion of thick wire fatigue life. Increasing the wire aspect ratio lowers its critical stress and increases its fatigue life. Moreover, we found that CucorAl wire has superior performance and longer fatigue life than Al wire.

Analysis of ultra-relativistic charged particle beam and stretched wire measurement interactions with cylindrically symmetric structures

International Nuclear Information System (INIS)

Deibele, C.E.

1996-01-01

The beam impedance and wakefield are quantities which describe the stability of charged particles in their trajectory within an accelerator. The stretched wire measurement technique is a method which estimates the beam impedance and wakefield. Definitions for the beam impedance, the wakefield, and the stretched wire measurement are presented. A pillbox resonator with circular beampipes is studied for its relatively simple profile and mode structure. Theoretical predictions and measurement data are presented for the interaction of various charged particle beams and center conductor geometries between the cavity and beampipe. Time domain predictions for the stretched wire measurement and wakefield are presented and are shown to be a linear interaction

A three-dimensional mathematical model to predict air-cooling flow and temperature distribution of wire loops in the Stelmor air-cooling system

International Nuclear Information System (INIS)

Hong, Lingxiang; Wang, Bo; Feng, Shuai; Yang, Zhiliang; Yu, Yaowei; Peng, Wangjun; Zhang, Jieyu

2017-01-01

Highlights: • A 3-dimentioanl mathematical models for complex wire loops was set up in Stelmor. • The air flow field in the cooling process was simulated. • The convective heat transfer coefficient was simulated coupled with air flow field. • The temperature distribution with distances was predicted. - Abstract: Controlling the forced air cooling conditions in the Stelmor conveyor line is important for improving the microstructure and mechanical properties of steel wire rods. A three-dimensional mathematical model incorporating the turbulent flow of the cooling air and heat transfer of the wire rods was developed to predict the cooling process in the Stelmor air-cooling line of wire rolling mills. The distribution of cooling air from the plenum chamber and the forced convective heat transfer coefficient for the wire loops were simulated at the different locations over the conveyor. The temperature profiles and cooling curves of the wire loops in Stelmor conveyor lines were also calculated by considering the convective heat transfer, radiative heat transfer as well as the latent heat during transformation. The calculated temperature results using this model agreed well with the available measured results in the industrial tests. Thus, it was demonstrated that this model can be useful for studying the air-cooling process and predicting the temperature profile and microstructure evolution of the wire rods.

A new correction method serving to eliminate the parabola effect of flatbed scanners used in radiochromic film dosimetry

Energy Technology Data Exchange (ETDEWEB)

Poppinga, D., E-mail: daniela.poppinga@uni-oldenburg.de; Schoenfeld, A. A.; Poppe, B. [Medical Radiation Physics, Carl v. Ossietzky University, Oldenburg 26127, Germany and Department for Radiation Oncology, Pius Hospital, Oldenburg 26121 (Germany); Doerner, K. J. [Radiotherapy Department, General Hospital, Celle 29223 (Germany); Blanck, O. [CyberKnife Center Northern Germany, Güstrow 18273, Germany and Department for Radiation Oncology, University Clinic Schleswig-Holstein, Lübeck 23562 (Germany); Harder, D. [Medical Physics and Biophysics, Georg-August-University, Göttingen 37073 (Germany)

2014-02-15

Purpose: The purpose of this study is the correction of the lateral scanner artifact, i.e., the effect that, on a large homogeneously exposed EBT3 film, a flatbed scanner measures different optical densities at different positions along thex axis, the axis parallel to the elongated light source. At constant dose, the measured optical densitiy profiles along this axis have a parabolic shape with significant dose dependent curvature. Therefore, the effect is shortly called the parabola effect. The objective of the algorithm developed in this study is to correct for the parabola effect. Any optical density measured at given position x is transformed into the equivalent optical density c at the apex of the parabola and then converted into the corresponding dose via the calibration of c versus dose. Methods: For the present study EBT3 films and an Epson 10000XL scanner including transparency unit were used for the analysis of the parabola effect. The films were irradiated with 6 MV photons from an Elekta Synergy accelerator in a RW3 slab phantom. In order to quantify the effect, ten film pieces with doses graded from 0 to 20.9 Gy were sequentially scanned at eight positions along thex axis and at six positions along the z axis (the movement direction of the light source) both for the portrait and landscape film orientations. In order to test the effectiveness of the new correction algorithm, the dose profiles of an open square field and an IMRT plan were measured by EBT3 films and compared with ionization chamber and ionization chamber array measurement. Results: The parabola effect has been numerically studied over the whole measuring field of the Epson 10000XL scanner for doses up to 20.9 Gy and for both film orientations. The presented algorithm transforms any optical density at positionx into the equivalent optical density that would be measured at the same dose at the apex of the parabola. This correction method has been validated up to doses of 5.2 Gy all over the

A new correction method serving to eliminate the parabola effect of flatbed scanners used in radiochromic film dosimetry

International Nuclear Information System (INIS)

Poppinga, D.; Schoenfeld, A. A.; Poppe, B.; Doerner, K. J.; Blanck, O.; Harder, D.

2014-01-01

Purpose: The purpose of this study is the correction of the lateral scanner artifact, i.e., the effect that, on a large homogeneously exposed EBT3 film, a flatbed scanner measures different optical densities at different positions along thex axis, the axis parallel to the elongated light source. At constant dose, the measured optical densitiy profiles along this axis have a parabolic shape with significant dose dependent curvature. Therefore, the effect is shortly called the parabola effect. The objective of the algorithm developed in this study is to correct for the parabola effect. Any optical density measured at given position x is transformed into the equivalent optical density c at the apex of the parabola and then converted into the corresponding dose via the calibration of c versus dose. Methods: For the present study EBT3 films and an Epson 10000XL scanner including transparency unit were used for the analysis of the parabola effect. The films were irradiated with 6 MV photons from an Elekta Synergy accelerator in a RW3 slab phantom. In order to quantify the effect, ten film pieces with doses graded from 0 to 20.9 Gy were sequentially scanned at eight positions along thex axis and at six positions along the z axis (the movement direction of the light source) both for the portrait and landscape film orientations. In order to test the effectiveness of the new correction algorithm, the dose profiles of an open square field and an IMRT plan were measured by EBT3 films and compared with ionization chamber and ionization chamber array measurement. Results: The parabola effect has been numerically studied over the whole measuring field of the Epson 10000XL scanner for doses up to 20.9 Gy and for both film orientations. The presented algorithm transforms any optical density at positionx into the equivalent optical density that would be measured at the same dose at the apex of the parabola. This correction method has been validated up to doses of 5.2 Gy all over the

A new correction method serving to eliminate the parabola effect of flatbed scanners used in radiochromic film dosimetry.

Science.gov (United States)

Poppinga, D; Schoenfeld, A A; Doerner, K J; Blanck, O; Harder, D; Poppe, B

2014-02-01

The purpose of this study is the correction of the lateral scanner artifact, i.e., the effect that, on a large homogeneously exposed EBT3 film, a flatbed scanner measures different optical densities at different positions along the x axis, the axis parallel to the elongated light source. At constant dose, the measured optical density profiles along this axis have a parabolic shape with significant dose dependent curvature. Therefore, the effect is shortly called the parabola effect. The objective of the algorithm developed in this study is to correct for the parabola effect. Any optical density measured at given position x is transformed into the equivalent optical density c at the apex of the parabola and then converted into the corresponding dose via the calibration of c versus dose. For the present study EBT3 films and an Epson 10000XL scanner including transparency unit were used for the analysis of the parabola effect. The films were irradiated with 6 MV photons from an Elekta Synergy accelerator in a RW3 slab phantom. In order to quantify the effect, ten film pieces with doses graded from 0 to 20.9 Gy were sequentially scanned at eight positions along the x axis and at six positions along the z axis (the movement direction of the light source) both for the portrait and landscape film orientations. In order to test the effectiveness of the new correction algorithm, the dose profiles of an open square field and an IMRT plan were measured by EBT3 films and compared with ionization chamber and ionization chamber array measurement. The parabola effect has been numerically studied over the whole measuring field of the Epson 10000XL scanner for doses up to 20.9 Gy and for both film orientations. The presented algorithm transforms any optical density at position x into the equivalent optical density that would be measured at the same dose at the apex of the parabola. This correction method has been validated up to doses of 5.2 Gy all over the scanner bed with 2D dose

1998 wire development workshop proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-04-01

This report consists of vugraphs of the presentations at the conference. The conference was divided into the following sessions: (1) First Generation Wire Development: Status and Issues; (2) First Generation Wire in Pre-Commercial Prototypes; (3) Second Generation Wire Development: Private Sector Progress and Issues; (4) Second Generation Wire Development: Federal Laboratories; and (5) Fundamental Research Issues for HTS Wire Development.

1998 wire development workshop proceedings

International Nuclear Information System (INIS)

1998-04-01

This report consists of vugraphs of the presentations at the conference. The conference was divided into the following sessions: (1) First Generation Wire Development: Status and Issues; (2) First Generation Wire in Pre-Commercial Prototypes; (3) Second Generation Wire Development: Private Sector Progress and Issues; (4) Second Generation Wire Development: Federal Laboratories; and (5) Fundamental Research Issues for HTS Wire Development

Right wire in orthodontics: a review

OpenAIRE

Ali, Hashim

2015-01-01

Quality of orthodontic wire such as stiffness, hardness, resiliency, elasticity and working range are important determinants of the effectivenes of tooth movement. Commonly used types of orthodontic arch wire:1) stainless steel(ss) wire, 2) conventional nickel- titanium (NiTi)alloy wire,3) improved super elastic NiTi- alloy wire( also called low hysteresis(LH)wire), and titanium molybdenum alloy(TMA) wire.

Application of irradiated wire

International Nuclear Information System (INIS)

Uda, I.; Kozima, K.; Suzuki, S.; Tada, S.; Torisu, S.; Veno, K.

1984-01-01

Rubber insulated wires are still useful for internal wiring in motor vehicles and electrical equipment because of flexibility and toughness. Irradiated cross-linked rubber materials have been successfully introduced for use with fusible link wire and helically coiled cord

Scanners for analytic print measurement: the devil in the details

Science.gov (United States)

Zeise, Eric K.; Williams, Don; Burns, Peter D.; Kress, William C.

2007-01-01

Inexpensive and easy-to-use linear and area-array scanners have frequently substituted as colorimeters and densitometers for low-frequency (i.e., large area) hard copy image measurement. Increasingly, scanners are also being used for high spatial frequency, image microstructure measurements, which were previously reserved for high performance microdensitometers. In this paper we address characteristics of flatbed reflection scanners in the evaluation of print uniformity, geometric distortion, geometric repeatability and the influence of scanner MTF and noise on analytic measurements. Suggestions are made for the specification and evaluation of scanners to be used in print image quality standards that are being developed.

Free-space wavelength-multiplexed optical scanner demonstration.

Science.gov (United States)

Yaqoob, Zahid; Riza, Nabeel A

2002-09-10

Experimental demonstration of a no-moving-parts free-space wavelength-multiplexed optical scanner (W-MOS) is presented. With fast tunable lasers or optical filters and planar wavelength dispersive elements such as diffraction gratings, this microsecond-speed scanner enables large several-centimeter apertures for subdegree angular scans. The proposed W-MOS design incorporates a unique optical amplifier and variable optical attenuator combination that enables the calibration and modulation of the scanner response, leading to any desired scanned laser beam power shaping. The experimental setup uses a tunable laser centered at 1560 nm and a 600-grooves/mm blazed reflection grating to accomplish an angular scan of 12.92 degrees as the source is tuned over an 80-nm bandwidth. The values for calculated maximum optical beam divergance, required wavelength resolution, beam-pointing accuracy, and measured scanner insertion loss are 1.076 mrad, 0.172 nm, 0.06 mrad, and 4.88 dB, respectively.

Portable CT scanners for use on live trees and standing columns

International Nuclear Information System (INIS)

Onoe, M.; Tsao, J.W.; Yamada, H.; Nakamura, H.; Kogure, J.; Kawamura, H.; Isono, E.; Maeda, Y.; Matsumoto, S.

1985-01-01

Computed tomography (CT) is a technique to reconstruct a crosssection of a test object from multiple projections obtained using e.g. x-rays. A large number of medical CT scanners and a few industrial CT scanners have been used. Most of these scanners are fixed installations. In contrast, we developed portable CT scanners for nondestructive testing of live trees and standing building columns in field environment. The resolution of these scanners is high enough to reveal details of annual rings of trees and timbers. The scanners have been useful in a wide range of applications. This paper presents two types of scanners with small and large apertures, a system for quick look of reconstruction and a few examples of applications

Measurement of multi-slice computed tomography dose profile with the Dose Magnifying Glass and the MOSkin radiation dosimeter

International Nuclear Information System (INIS)

Lian, C.P.L.; Wong, J.H.D.; Young, A.; Cutajar, D.; Petasecca, M.; Lerch, M.L.F.; Rosenfeld, A.B.

2013-01-01

This study describes the application of two in-house developed dosimeters, the Dose Magnifying Glass (DMG) and the MOSkin dosimeter at the Centre for Medical Radiation Physics, University of Wollongong, Australia, for the measurement of CT dose profiles for a clinical diagnostic 16-slice MSCT scanner. Two scanner modes were used; axial mode and helical mode, and the effect of varying beam collimation and pitch was studied. With an increase in beam collimation in axial mode and an increase of CT pitch in helical mode, cumulative point dose at scanner isocentre decreased while FWHM increased. There was generally good agreement to within 3% between the acquired dose profiles obtained by the DMG and the film except at dose profile tails, where film over-responded by up to 30% due to its intrinsic depth dose dependence at low doses. -- Highlights: ► This study shows the CT beam profiles acquired with our institution's detectors. ► The DMG is a relative dosimeter calibrated to absolute MOSkin readings. ► There was good agreement between dose profiles acquired by the DMG and the film

Effect of discrete wires on the implosion dynamics of wire array Z pinches

International Nuclear Information System (INIS)

Lebedev, S. V.; Beg, F. N.; Bland, S. N.; Chittenden, J. P.; Dangor, A. E.; Haines, M. G.; Kwek, K. H.; Pikuz, S. A.; Shelkovenko, T. A.

2001-01-01

A phenomenological model of wire array Z-pinch implosions, based on the analysis of experimental data obtained on the mega-ampere generator for plasma implosion experiments (MAGPIE) generator [I. H. Mitchell , Rev. Sci. Instrum. 67, 1533 (1996)], is described. The data show that during the first ∼80% of the implosion the wire cores remain stationary in their initial positions, while the coronal plasma is continuously jetting from the wire cores to the array axis. This phase ends by the formation of gaps in the wire cores, which occurs due to the nonuniformity of the ablation rate along the wires. The final phase of the implosion starting at this time occurs as a rapid snowplow-like implosion of the radially distributed precursor plasma, previously injected in the interior of the array. The density distribution of the precursor plasma, being peaked on the array axis, could be a key factor providing stability of the wire array implosions operating in the regime of discrete wires. The modified ''initial'' conditions for simulations of wire array Z-pinch implosions with one-dimension (1D) and two-dimensions (2D) in the r--z plane, radiation-magnetohydrodynamic (MHD) codes, and a possible scaling to a larger drive current are discussed

Multimodality Registration without a Dedicated Multimodality Scanner

Directory of Open Access Journals (Sweden)

Bradley J. Beattie

2007-03-01

Full Text Available Multimodality scanners that allow the acquisition of both functional and structural image sets on a single system have recently become available for animal research use. Although the resultant registered functional/structural image sets can greatly enhance the interpretability of the functional data, the cost of multimodality systems can be prohibitive, and they are often limited to two modalities, which generally do not include magnetic resonance imaging. Using a thin plastic wrap to immobilize and fix a mouse or other small animal atop a removable bed, we are able to calculate registrations between all combinations of four different small animal imaging scanners (positron emission tomography, single-photon emission computed tomography, magnetic resonance, and computed tomography [CT] at our disposal, effectively equivalent to a quadruple-modality scanner. A comparison of serially acquired CT images, with intervening acquisitions on other scanners, demonstrates the ability of the proposed procedures to maintain the rigidity of an anesthetized mouse during transport between scanners. Movement of the bony structures of the mouse was estimated to be 0.62 mm. Soft tissue movement was predominantly the result of the filling (or emptying of the urinary bladder and thus largely constrained to this region. Phantom studies estimate the registration errors for all registration types to be less than 0.5 mm. Functional images using tracers targeted to known structures verify the accuracy of the functional to structural registrations. The procedures are easy to perform and produce robust and accurate results that rival those of dedicated multimodality scanners, but with more flexible registration combinations and while avoiding the expense and redundancy of multimodality systems.

Wire-Mesh Tomography Measurements of Void Fraction in Rectangular Bubble Columns

International Nuclear Information System (INIS)

Reddy Vanga, B.N.; Lopez de Bertodano, M.A.; Zaruba, A.; Prasser, H.M.; Krepper, E.

2004-01-01

Bubble Columns are widely used in the process industry and their scale-up from laboratory scale units to industrial units have been a subject of extensive study. The void fraction distribution in the bubble column is affected by the column size, superficial velocity of the dispersed phase, height of the liquid column, size of the gas bubbles, flow regime, sparger design and geometry of the bubble column. The void fraction distribution in turn affects the interfacial momentum transfer in the bubble column. The void fraction distribution in a rectangular bubble column 10 cm wide and 2 cm deep has been measured using Wire-Mesh Tomography. Experiments were performed in an air-water system with the column operating in the dispersed bubbly flow regime. The experiments also serve the purpose of studying the performance of wire-mesh sensors in batch flows. A 'wall peak' has been observed in the measured void fraction profiles, for the higher gas flow rates. This 'wall peak' seems to be unique, as this distribution has not been previously reported in bubble column literature. Low gas flow rates yielded the conventional 'center peak' void profile. The effect of column height and superficial gas velocity on the void distribution has been investigated. Wire-mesh Tomography also facilitates the measurement of bubble size distribution in the column. This paper presents the measurement principle and the experimental results for a wide range of superficial gas velocities. (authors)

Utilization pattern of whole body computed tomography scanner

International Nuclear Information System (INIS)

Youn, Chul Ho; Lee, Sang Suk

1986-01-01

Computed tomography scanner (CT scanner) is one of the most expensive and sophisticated diagnostic tool and has already been utilized in many hospitals in Korea. The price as well as operating costs of CT scanner is so expensive as to regulate its installment by government even in the United States. In order to identify the efficient utilization of the CT scanner, the utilization pattern for CT scanning was analyzed at three general hospital in seoul. The results are as follows: 1. Five out of one thousand outpatients and five out of one hundred inpatients were CT scanned. 2. Eighty percent of patients who were scanned were those of inpatients of the hospitals where the scanned are installed. 3. Head standings constitute 45.6 percent of examinations, internal medicine 63.8 percent, and 38.5 percent neurosurgery respectively. 4. The rate of indication for CT scanning showed no statistically significant difference between insured and non-insured groups. 5. Computed tomography scanner units were operated 5.5 days a week in average and full operation rate was 79.5% in average. 6. The major diagnoses mode by head scanning were: hematoma (56.7%), infarction (12.6%), tumor (8.2%), and hydrocephalus (4.4%). 7. Number of patients taken CT Scanning was 43 persons a week in average for each whole body scanner unit

Wire core reactor for NTP

International Nuclear Information System (INIS)

Harty, R.B.

1991-01-01

The development of the wire core system for Nuclear Thermal Propulsion (NTP) that took place from 1963 to 1965 is discussed. A wire core consists of a fuel wire with spacer wires. It's an annular flow core having a central control rod. There are actually four of these, with beryllium solid reflectors on both ends and all the way around. Much of the information on the concept is given in viewgraph form. Viewgraphs are presented on design details of the wire core, the engine design, engine weight vs. thrust, a technique used to fabricate the wire fuel element, and axial temperature distribution

Input Scanners: A Growing Impact In A Diverse Marketplace

Science.gov (United States)

Marks, Kevin E.

1989-08-01

Just as newly invented photographic processes revolutionized the printing industry at the turn of the century, electronic imaging has affected almost every computer application today. To completely emulate traditionally mechanical means of information handling, computer based systems must be able to capture graphic images. Thus, there is a widespread need for the electronic camera, the digitizer, the input scanner. This paper will review how various types of input scanners are being used in many diverse applications. The following topics will be covered: - Historical overview of input scanners - New applications for scanners - Impact of scanning technology on select markets - Scanning systems issues

SCT-4800T whole body X-ray CT scanner

International Nuclear Information System (INIS)

Okumura, Yoshitaka; Sato, Yukio; Kuwahara, Hiroshi

1994-01-01

A whole body X-ray CT scanner, the SCT-4800T (trade name: INTELLECT series), has been developed. This system is the first CT scanner that is combined with general radiographic functions. The general radiographic functions include a patient couch with film casette and several tube support systems along with the CT scanner. This newly designed CT scanner also features a compact and light-weight gantry with a 700 mm diameter apperture and user-friendly operater's console. The SCT-4800T brings a new level of patient and operator comfort to the emergency radiology examination site. (author)

Experimental testing and modelling of a resistive type superconducting fault current limiter using MgB2 wire

International Nuclear Information System (INIS)

Smith, A C; Pei, X; Oliver, A; Husband, M; Rindfleisch, M

2012-01-01

A prototype resistive superconducting fault current limiter (SFCL) was developed using single-strand round magnesium diboride (MgB 2 ) wire. The MgB 2 wire was wound with an interleaved arrangement to minimize coil inductance and provide adequate inter-turn voltage withstand capability. The temperature profile from 30 to 40 K and frequency profile from 10 to 100 Hz at 25 K were tested and reported. The quench properties of the prototype coil were tested using a high current test circuit. The fault current was limited by the prototype coil within the first quarter-cycle. The prototype coil demonstrated reliable and repeatable current limiting properties and was able to withstand a potential peak current of 372 A for one second without any degradation of performance. A three-strand SFCL coil was investigated and demonstrated scaled-up current capacity. An analytical model to predict the behaviour of the prototype single-strand SFCL coil was developed using an adiabatic boundary condition on the outer surface of the wire. The predicted fault current using the analytical model showed very good correlation with the experimental test results. The analytical model and a finite element thermal model were used to predict the temperature rise of the wire during a fault. (paper)

Radiation excited by a charged-particle bunch on a planar periodic wire structure

Directory of Open Access Journals (Sweden)

Andrey V. Tyukhtin

2014-12-01

Full Text Available The electromagnetic field of a bunch moving in the presence of a plane grid composed of thin parallel wires is considered by using the averaged boundary conditions method. Two different cases of motion are examined. In the first one, the bunch moves at a constant distance from the grid orthogonally to the wires. The excited surface wave is presented in the form of a spectral integral for a thin bunch with an arbitrary longitudinal profile. The wave propagates along the wires and does not decay with distance (if dissipation is negligible. Energy losses of the bunch over a unit path are obtained. In the second case, the bunch orthogonally crosses the wire grid. The volume and surface waves are separately analyzed. Properties of the spectral angular density of energy of volume radiation in the far-field zone are described. The energy losses due to the volume and surface radiation are determined. It is demonstrated that the structure of the surface waves in both cases allows determination of the length of the bunch.

Measuring micron size beams in the SLC final focus

International Nuclear Information System (INIS)

McCormick, D.; Ross, M.; DeBarger, S.

1994-10-01

A pair of high resolution wire scanners have been built and installed in the SLC final focus. The final focus optics uses a set of de-magnifying telescopes, and an ideal location for a beam size monitor is at one of the magnified image points of the interaction point. The image point chosen for these scanners is in the middle of a large bend magnet. The design beam spots here are about 2 microns in the vertical and 20 microns in the horizontal plane. The scanners presented a number of design challenges. In this paper we discuss the mechanical design of the scanner, and fabrication techniques of its ceramic wire support card which holds many 4 and 7 um carbon wires. Accurate motion of the wire during a scan is critical. In this paper we describe tests of stepper motors, gear combinations, and radiation hardened encoders needed to produce the required motion with a step resolution of 80 nanometers. Also presented here are the results of scattered radiation detector placement studies carried out to optimize the signal from the 4 micron wires. Finally, we present measurements from the scanner

Water Desalination with Wires

NARCIS (Netherlands)

Porada, S.; Sales, B.B.; Hamelers, H.V.M.; Biesheuvel, P.M.

2012-01-01

We show the significant potential of water desalination using a novel capacitive wire-based technology in which anode/cathode wire pairs are constructed from coating a thin porous carbon electrode layer on top of electrically conducting rods (or wires). By alternately dipping an array of electrode

Developments in holographic-based scanner designs

Science.gov (United States)

Rowe, David M.

1997-07-01

Holographic-based scanning systems have been used for years in the high resolution prepress markets where monochromatic lasers are generally utilized. However, until recently, due to the dispersive properties of holographic optical elements (HOEs), along with the high cost associated with recording 'master' HOEs, holographic scanners have not been able to penetrate major scanning markets such as the laser printer and digital copier markets, low to mid-range imagesetter markets, and the non-contact inspection scanner market. Each of these markets has developed cost effective laser diode based solutions using conventional scanning approaches such as polygon/f-theta lens combinations. In order to penetrate these markets, holographic-based systems must exhibit low cost and immunity to wavelength shifts associated with laser diodes. This paper describes recent developments in the design of holographic scanners in which multiple HOEs, each possessing optical power, are used in conjunction with one curved mirror to passively correct focal plane position errors and spot size changes caused by the wavelength instability of laser diodes. This paper also describes recent advancements in low cost production of high quality HOEs and curved mirrors. Together these developments allow holographic scanners to be economically competitive alternatives to conventional devices in every segment of the laser scanning industry.

Towards plant wires

OpenAIRE

Adamatzky, Andrew

2014-01-01

In experimental laboratory studies we evaluate a possibility of making electrical wires from living plants. In scoping experiments we use lettuce seedlings as a prototype model of a plant wire. We approximate an electrical potential transfer function by applying direct current voltage to the lettuce seedlings and recording output voltage. We analyse oscillation frequencies of the output potential and assess noise immunity of the plant wires. Our findings will be used in future designs of self...

Circumference estimation using 3D-whole body scanners and shadow scanner

NARCIS (Netherlands)

Daanen, H.A.M.

1998-01-01

Clothing designers and manufacturers use traditional body dimensions as their basis. When 3D-whole body scanners are introduced to determine the body dimensions, a conversion has to be made, since scan determined circumference measures are slightly larger than the traditional values. This pilot

Manually operated small envelope scanner system

Energy Technology Data Exchange (ETDEWEB)

Sword, Charles Keith

2017-04-18

A scanner system and method for acquisition of position-based ultrasonic inspection data are described. The scanner system includes an inspection probe and a first non-contact linear encoder having a first sensor and a first scale to track inspection probe position. The first sensor is positioned to maintain a continuous non-contact interface between the first sensor and the first scale and to maintain a continuous alignment of the first sensor with the inspection probe. The scanner system may be used to acquire two-dimensional inspection probe position data by including a second non-contact linear encoder having a second sensor and a second scale, the second sensor positioned to maintain a continuous non-contact interface between the second sensor and the second scale and to maintain a continuous alignment of the second sensor with the first sensor.

Evolution of cementite morphology in pearlitic steel wire during wet wire drawing

DEFF Research Database (Denmark)

Zhang, Xiaodan; Godfrey, Andrew; Hansen, Niels

2010-01-01

The evolution of the cementite phase during wet wire drawing of a pearlitic steel wire has been followed as a function of strain. Particular attention has been given to a quantitative characterization of changes in the alignment and in the dimensions of the cementite phase. Scanning electron...... microscope observations show that cementite plates become increasingly aligned with the wire axis as the drawing strain is increased. Measurements in the transmission electron microscope show that the cementite deforms plastically during wire drawing , with the average thickness of the cementite plates...... decreasing from 19 nm (ε = 0) to 2 nm (ε = 3.7) in correspondence with the reduction in wire diameter. The deformation of the cementite is strongly related to plastic deformation in the ferrite, with coarse slip steps, shear bands and cracks in the cementite plates/particles observed parallel to either {110...

Development and performance evaluation of an experimental fine pitch detector multislice CT scanner.

Science.gov (United States)

Imai, Yasuhiro; Nukui, Masatake; Ishihara, Yotaro; Fujishige, Takashi; Ogata, Kentaro; Moritake, Masahiro; Kurochi, Haruo; Ogata, Tsuyoshi; Yahata, Mitsuru; Tang, Xiangyang

2009-04-01

The authors have developed an experimental fine pitch detector multislice CT scanner with an ultrasmall focal spot x-ray tube and a high-density matrix detector through current CT technology. The latitudinal size of the x-ray tube focal spot was 0.4 mm. The detector dimension was 1824 channels (azimuthal direction) x 32 rows (longitudinal direction) at row width of 0.3125 mm, in which a thinner reflected separator surrounds each detector cell coupled with a large active area photodiode. They were mounted on a commercial 64-slice CT scanner gantry while the scan field of view (50 cm) and gantry rotation speed (0.35 s) can be maintained. The experimental CT scanner demonstrated the spatial resolution of 0.21-0.22 mm (23.8-22.7 lp/cm) with the acrylic slit phantom and in-plane 50%-MTF 9.0 lp/cm and 10%-MTF 22.0 lp/cm. In the longitudinal direction, it demonstrated the spatial resolution of 0.24 mm with the high-resolution insert of the CATPHAN phantom and 0.34 mm as the full width at half maximum of the slice sensitivity profile. In low-contrast detectability, 3 mm at 0.3% was visualized at the CTDI(vol) of 47.2 mGy. Two types of 2.75 mm diameter vessel phantoms with in-stent stenosis at 25%, 50%, and 75% stair steps were scanned, and the reconstructed images can clearly resolve the stenosis at each case. The experimental CT scanner provides high-resolution imaging while maintaining low-contrast detectability, demonstrating the potentiality for clinical applications demanding high spatial resolution, such as imaging of inner ear, lung, and bone, or low-contrast detectability, such as imaging of coronary artery.

Particle discrimination by an automatic scanner for nuclear emulsion plates

International Nuclear Information System (INIS)

Heinecke, W.; Fischer, B.E.

1976-01-01

An automatic scanner for nuclear emulsion plates has been improved by adding particle discrimination. By determination of the mean luminosity of tracks in darkfield illumination in addition to the track length a clear discrimination has been obtained, at least for lighter particles. The scanning speed of the original automatic scanner has not been reduced. The scanner works up to 200 times faster than a human scanner. Besides the particle discrimination the determination of the mean track luminosity led to a lower perturbation sensitivity with respect to a high background of accidentally developed silvergrains, scratches in emulsion etc. The reproducibility of the results obtained by the automatic scanner is better than 5%. (Auth.)

Using wire shaping techniques and holographic optics to optimize deposition characteristics in wire-based laser cladding.

Science.gov (United States)

Goffin, N J; Higginson, R L; Tyrer, J R

2016-12-01

In laser cladding, the potential benefits of wire feeding are considerable. Typical problems with the use of powder, such as gas entrapment, sub-100% material density and low deposition rate are all avoided with the use of wire. However, the use of a powder-based source material is the industry standard, with wire-based deposition generally regarded as an academic curiosity. This is because, although wire-based methods have been shown to be capable of superior quality results, the wire-based process is more difficult to control. In this work, the potential for wire shaping techniques, combined with existing holographic optical element knowledge, is investigated in order to further improve the processing characteristics. Experiments with pre-placed wire showed the ability of shaped wire to provide uniformity of wire melting compared with standard round wire, giving reduced power density requirements and superior control of clad track dilution. When feeding with flat wire, the resulting clad tracks showed a greater level of quality consistency and became less sensitive to alterations in processing conditions. In addition, a 22% increase in deposition rate was achieved. Stacking of multiple layers demonstrated the ability to create fully dense, three-dimensional structures, with directional metallurgical grain growth and uniform chemical structure.

Evolution of cementite morphology in pearlitic steel wire during wet wire drawing

International Nuclear Information System (INIS)

Zhang Xiaodan; Godfrey, Andrew; Hansen, Niels; Huang Xiaoxu; Liu Wei; Liu Qing

2010-01-01

The evolution of the cementite phase during wet wire drawing of a pearlitic steel wire has been followed as a function of strain. Particular attention has been given to a quantitative characterization of changes in the alignment and in the dimensions of the cementite phase. Scanning electron microscope observations show that cementite plates become increasingly aligned with the wire axis as the drawing strain is increased. Measurements in the transmission electron microscope show that the cementite deforms plastically during wire drawing , with the average thickness of the cementite plates decreasing from 19 nm (ε = 0) to 2 nm (ε = 3.7) in correspondence with the reduction in wire diameter. The deformation of the cementite is strongly related to plastic deformation in the ferrite, with coarse slip steps, shear bands and cracks in the cementite plates/particles observed parallel to either {110} α or {112} α slip plane traces in the ferrite.

1 mil gold bond wire study.

Energy Technology Data Exchange (ETDEWEB)

Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W.; Rutherford, Brian Milne

2013-05-01

In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, the gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.

Corrosion of Wires on Wooden Wire-Bound Packaging Crates

Science.gov (United States)

Samuel L. Zelinka; Stan Lebow

2015-01-01

Wire-bound packaging crates are used by the US Army to transport materials. Because these crates may be exposed to harsh environments, they are dip-treated with a wood preservative (biocide treatment). For many years, zinc-naphthenate was the most commonly used preservative for these packaging crates and few corrosion problems with the wires were observed. Recently,...

Myocardium scintigraphy and coronaries scanner: results and respective contribution of these two examinations; Scintigraphie myocardique et scanner coronaire: resultats et apport respectif des deux examens

Energy Technology Data Exchange (ETDEWEB)

Songy, B.; Balestrini, V.; Sablayrolles, J.L.; Vigoni, F.; Lussato, D. [Centre cardiologique du Nord (CCN), Saint-Denis, (France); Faccio, F. [fondation San Geronimo, Santa Fe, (Argentina)

2009-05-15

The objective were to evaluate the results and the respective contribution of the myocardium scintigraphy and the coro-scanner. It exists an excellent correlation between a normal scanner and a normal scintigraphy (97%). 30% of patients having non tight stenosis at scanner and 60% of these ones having tight stenosis have a scintigraphy ischemia; An abnormal scanner, whatever be the the degree of stenosis must be completed by a test of myocardium ischemia. The actual limitations of the coro-scanner (64 gills) are in relation with its spatial resolution (quantification) and temporal resolution (right coronary). The choice of the diagnosis examination to realize in first intention must depend on the age and prevalence of the coronary disease. (N.C.)

APLIKASI INFO HALAL MENGGUNAKAN BARCODE SCANNER UNTUK SMARTPHONE ANDROID

Directory of Open Access Journals (Sweden)

Beki Subeki

2016-05-01

Full Text Available Abstract – In the production and trade of food products in the era of globalization, people are consuming, especially Muslims need to be given the knowledge, information and access to adequate in order to obtain the correct information about the halal status of products bought. The use of barcode scanners halal product information using the mobile platform is effective and useful for the public to find out information on a product. Barcode scanners can be read by optical scanners called barcode readers or scanned from an image by special software. In Indonesia, most mobile phones have the scanning software for 2D codes, and similar devices available via smartphone.   Keywords : Barcode Scanner, Mobile Platform, Halal Products, Smartphone     Abstrak - Dalam kegiatan produksi dan perdagangan produk pangan di era globalisasi ini, masyarakat yang mengkonsumsi, khususnya umat islam perlu diberikan pengetahuan tentang kehalalan produk, informasi dan akses yang memadai agar memperoleh informasi yang benar tentang status kehalalan produk yang dibelinya. Penggunaan barcode scanner informasi produk halal dengan menggunakan mobile platform dinilai cukup efektif dan berguna bagi masyarakat luas untuk mengetahui informasi sebuah produk. Barcode scanner dapat dibaca oleh pemindai optik yang disebut pembaca kode batang atau dipindai dari sebuah gambar oleh perangkat lunak khusus. Di Indonesia, kebanyakan telepon genggam memiliki perangkat lunak pemindai untuk kode 2D, dan perangkat sejenis tersedia melalui smartphone.   Kata Kunci: Barcode Scanner, Mobile Platform, Produk Halal, Smartphone

A simple scanner for Compton tomography

CERN Document Server

Cesareo, R; Brunetti, A; Golosio, B; Castellano, A

2002-01-01

A first generation CT-scanner was designed and constructed to carry out Compton images. This CT-scanner is composed of a 80 kV, 5 mA X-ray tube and a NaI(Tl) X-ray detector; the tube is strongly collimated, generating a X-ray beam of 2 mm diameter, whilst the detector is not collimated to collect Compton photons from the whole irradiated cylinder. The performances of the equipment were tested contemporaneous transmission and Compton images.

128 slice computed tomography dose profile measurement using thermoluminescent dosimeter

International Nuclear Information System (INIS)

Salehhon, N; Hashim, S; Karim, M K A; Ang, W C; Musa, Y; Bahruddin, N A

2017-01-01

The increasing use of computed tomography (CT) in clinical practice marks the needs to understand the dose descriptor and dose profile. The purposes of the current study were to determine the CT dose index free-in-air (CTDI air ) in 128 slice CT scanner and to evaluate the single scan dose profile (SSDP). Thermoluminescent dosimeters (TLD-100) were used to measure the dose profile of the scanner. There were three sets of CT protocols where the tube potential (kV) setting was manipulated for each protocol while the rest of parameters were kept constant. These protocols were based from routine CT abdominal examinations for male adult abdomen. It was found that the increase of kV settings made the values of CTDI air increased as well. When the kV setting was changed from 80 kV to 120 kV and from 120 kV to 140 kV, the CTDI air values were increased as much as 147.9% and 53.9% respectively. The highest kV setting (140 kV) led to the highest CTDI air value (13.585 mGy). The p -value of less than 0.05 indicated that the results were statistically different. The SSDP showed that when the kV settings were varied, the peak sharpness and height of Gaussian function profiles were affected. The full width at half maximum (FWHM) of dose profiles for all protocols were coincided with the nominal beam width set for the measurements. The findings of the study revealed much information on the characterization and performance of 128 slice CT scanner. (paper)

Forming Refractory Insulation On Copper Wire

Science.gov (United States)

Setlock, J.; Roberts, G.

1995-01-01

Alternative insulating process forms flexible coat of uncured refractory insulating material on copper wire. Coated wire formed into coil or other complex shape. Wire-coating apparatus forms "green" coat on copper wire. After wire coiled, heating converts "green" coat to refractory electrical insulator. When cured to final brittle form, insulating material withstands temperatures above melting temperature of wire. Process used to make coils for motors, solenoids, and other electrical devices to be operated at high temperatures.

Cyclic Fatigue Resistance of Novel Rotary Files Manufactured from Different Thermal Treated Nickel-Titanium Wires in Artificial Canals.

Science.gov (United States)

Karataşlıoglu, E; Aydın, U; Yıldırım, C

2018-02-01

The aim of this in vitro study was to compare the static cyclic fatigue resistance of thermal treated rotary files with a conventional nickel-titanium (NiTi) rotary file. Four groups of 60 rotary files with similar file dimensions, geometries, and motion were selected. Groups were set as HyFlex Group [controlled memory wire (CM-Wire)], ProfileVortex Group (M-Wire), Twisted File Group (R-Phase Wire), and OneShape Group (conventional NiTi wire)] and tested using a custom-made static cyclic fatigue testing apparatus. The fracture time and fragment length of the each file was also recorded. Statistical analysis was performed using one-way analysis of variance and Tukey's test at the 95% confidence level (P = 0.05). The HyFlex group had a significantly higher mean cyclic fatigue resistance than the other three groups (P Wire alloy represented the best performance in cyclic fatigue resistance, and NiTi alloy in R-Phase had the second highest fatigue resistance. CM and R-Phase manufacturing technology processed to the conventional NiTi alloy enhance the cyclic fatigue resistance of files that have similar design and size. M-wire alloy did not show any superiority in cyclic fatigue resistance when compared with conventional NiTi wire.

Determination of transverse phase-space and momentum error from size measurements along the 50-MeV H- RCS injection line

International Nuclear Information System (INIS)

Cho, Y.; Crosbie, E.A.; Takeda, H.

1981-01-01

The 50-MeV H - injection line for the RCS at Argonne National Laboratory has 16 quadrupole and eight bending magnets. Horizontal and vertical profiles can be obtained at 12 wire scanner positions. Size information from these profiles can be used to determine the three ellipses parameters in each plane required to describe the transverse phase space. These locations that have dispersion permit the momentum error to be used as a fourth fitting parameter. The assumed accuracy of the size measurements provides an error matrix that predicts the rms errors of the fitted parameters

Wire chambers: Trends and alternatives

Energy Technology Data Exchange (ETDEWEB)

Regler, Meinhard

1992-05-15

The subtitle of this year's Vienna Wire Chamber Conference - 'Recent Trends and Alternative Techniques' - signalled that it covered a wide range of science and technology. While an opening Vienna talk by wire chamber pioneer Georges Charpak many years ago began 'Les funerailles des chambres a fils (the burial of wire chambers)', the contrary feeling this year was that wire chambers are very much alive!.

A flexible and wearable terahertz scanner

Science.gov (United States)

Suzuki, D.; Oda, S.; Kawano, Y.

2016-12-01

Imaging technologies based on terahertz (THz) waves have great potential for use in powerful non-invasive inspection methods. However, most real objects have various three-dimensional curvatures and existing THz technologies often encounter difficulties in imaging such configurations, which limits the useful range of THz imaging applications. Here, we report the development of a flexible and wearable THz scanner based on carbon nanotubes. We achieved room-temperature THz detection over a broad frequency band ranging from 0.14 to 39 THz and developed a portable THz scanner. Using this scanner, we performed THz imaging of samples concealed behind opaque objects, breakages and metal impurities of a bent film and multi-view scans of a syringe. We demonstrated a passive biometric THz scan of a human hand. Our results are expected to have considerable implications for non-destructive and non-contact inspections, such as medical examinations for the continuous monitoring of health conditions.

Review of wire chamber aging

International Nuclear Information System (INIS)

Va'Vra, J.

1986-02-01

This paper makes an overview of the wire chamber aging problems as a function of various chamber design parameters. It emphasizes the chemistry point of view and many examples are drawn from the plasma chemistry field as a guidance for a possible effort in the wire chamber field. The paper emphasizes the necessity of variable tuning, the importance of purity of the wire chamber environment, as well as it provides a practical list of presently known recommendations. In addition, several models of the wire chamber aging are qualitatively discussed. The paper is based on a summary talk given at the Wire Chamber Aging Workshop held at LBL, Berkeley on January 16-17, 1986. Presented also at Wire Chamber Conference, Vienna, February 25-28, 1986. 74 refs., 18 figs., 11 tabs

Design of active-neutron fuel rod scanner

International Nuclear Information System (INIS)

Griffith, G.W.; Menlove, H.O.

1996-01-01

An active-neutron fuel rod scanner has been designed for the assay of fissile materials in mixed oxide fuel rods. A 252 Cf source is located at the center of the scanner very near the through hole for the fuel rods. Spontaneous fission neutrons from the californium are moderated and induce fissions within the passing fuel rod. The rod continues past a combined gamma-ray and neutron shield where delayed gamma rays above 1 MeV are detected. We used the Monte Carlo code MCNP to design the scanner and review optimum materials and geometries. An inhomogeneous beryllium, graphite, and polyethylene moderator has been designed that uses source neutrons much more efficiently than assay systems using polyethylene moderators. Layers of borated polyethylene and tungsten are used to shield the detectors. Large NaI(Tl) detectors were selected to measure the delayed gamma rays. The enrichment zones of a thermal reactor fuel pin could be measured to within 1% counting statistics for practical rod speeds. Applications of the rod scanner include accountability of fissile material for safeguards applications, quality control of the fissile content in a fuel rod, and the verification of reactivity potential for mixed oxide fuels. (orig.)

Wire chambers: Trends and alternatives

International Nuclear Information System (INIS)

Regler, Meinhard

1992-01-01

The subtitle of this year's Vienna Wire Chamber Conference - 'Recent Trends and Alternative Techniques' - signalled that it covered a wide range of science and technology. While an opening Vienna talk by wire chamber pioneer Georges Charpak many years ago began 'Les funerailles des chambres a fils (the burial of wire chambers)', the contrary feeling this year was that wire chambers are very much alive!

Accuracy of single-abutment digital cast obtained using intraoral and cast scanners.

Science.gov (United States)

Lee, Jae-Jun; Jeong, Ii-Do; Park, Jin-Young; Jeon, Jin-Hun; Kim, Ji-Hwan; Kim, Woong-Chul

2017-02-01

Scanners are frequently used in the fabrication of dental prostheses. However, the accuracy of these scanners is variable, and little information is available. The purpose of this in vitro study was to compare the accuracy of cast scanners with that of intraoral scanners by using different image impression techniques. A poly(methyl methacrylate) master model was fabricated to replicate a maxillary first molar single-abutment tooth model. The master model was scanned with an accurate engineering scanner to obtain a true value (n=1) and with 2 intraoral scanners (CEREC Bluecam and CEREC Omnicam; n=6 each). The cast scanner scanned the master model and duplicated the dental stone cast from the master model (n=6). The trueness and precision of the data were measured using a 3-dimensional analysis program. The Kruskal-Wallis test was used to compare the different sets of scanning data, followed by a post hoc Mann-Whitney U test with a significance level modified by Bonferroni correction (α/6=.0083). The type 1 error level (α) was set at .05. The trueness value (root mean square: mean ±standard deviation) was 17.5 ±1.8 μm for the Bluecam, 13.8 ±1.4 μm for the Omnicam, 17.4 ±1.7 μm for cast scanner 1, and 12.3 ±0.1 μm for cast scanner 2. The differences between the Bluecam and the cast scanner 1 and between the Omnicam and the cast scanner 2 were not statistically significant (P>.0083), but a statistically significant difference was found between all the other pairs (POmnicam, 9.2 ±1.2 μm for cast scanner 1, and 6.9 ±2.6 μm for cast scanner 2. The differences between Bluecam and Omnicam and between Omnicam and cast scanner 1 were not statistically significant (P>.0083), but there was a statistically significant difference between all the other pairs (POmnicam in video image impression had better trueness than a cast scanner but with a similar level of precision. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by

Charpak hemispherical wire chamber

CERN Multimedia

1970-01-01

pieces. Mesures are of the largest one. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

Electrodeposition of nickel nano wire arrays

International Nuclear Information System (INIS)

Nur Ubaidah Saidin; Kok Kuan Ying; Ng Inn Khuan; Nurazila Mat Zali; Siti Salwa Zainal Abidin

2010-01-01

Synthesis, characterization and assembly of one-dimensional nickel nano wires prepared by template directed electrodeposition are discussed in this paper. Parallel arrays of high aspect ratio nickel nano wires were electrodeposited using electrolytes with different cations and pH. The nano wires were characterized using X-ray diffractometry and scanning electron microscopy. It was found that the orientations of the electro deposited Ni nano wires were governed by the deposition current and the electrolyte conditions. Free standing nickel nano wires can be obtained by dissolving the template. Due to the magnetic nature of the nano wires, magnetic alignment was employed to assemble and position the free standing nano wires in the device structure. (author)

Scanner Uniformity improvements for radiochromic film analysis with matt reflectance backing

International Nuclear Information System (INIS)

Butson, M.; Yu, P.K.N.

2011-01-01

Full text: A simple and reproducible method for increasing desktop scanner uniformity for the analysis of radiochromic films is presented. Scanner uniformity, especially in the non-scan direction, for transmission scanning is well known to be problematic for radiochromic film analysis and normally corrections need to be applied. These corrections are dependant on scanner coordinates and dose level applied which complicates dosimetry procedures. This study has highlighted that using reflectance scanning in combination with a matt, white backing material instead of the conventional gloss scanner finish, substantial increases in the scanner uniformity can be achieved within 90% of the scanning area. Uniformity within ±I% over the scanning area for our epsonV700 scanner tested was found. This is compared to within ±3% for reflection scanning with the gloss backing material and within ±4% for transmission scanning. The matt backing material used was simply 5 layers of standard quality white printing paper (80 g/m It was found that 5 layers was the optimal result for backing material however most of the improvements were seen with a minimum of 3 layers. Above 5 layers, no extra benefit was seen. This may eliminate the need to perform scanner corrections for position on the desktop scanners for radiochromic film dosimetry. (author)

Wire-number effects on high-power annular z-pinches and some characteristics at high wire number

Energy Technology Data Exchange (ETDEWEB)

SANFORD,THOMAS W. L.

2000-05-23

Characteristics of annular wire-array z-pinches as a function of wire number and at high wire number are reviewed. The data, taken primarily using aluminum wires on Saturn are comprehensive. The experiments have provided important insights into the features of wire-array dynamics critical for high x-ray power generation, and have initiated a renaissance in z-pinches when high numbers of wires are used. In this regime, for example, radiation environments characteristic of those encountered during the early pulses required for indirect-drive ICF ignition on the NIF have been produced in hohlraums driven by x-rays from a z-pinch, and are commented on here.

Wire-number effects on high-power annular z-pinches and some characteristics at high wire number

International Nuclear Information System (INIS)

SANFORD, THOMAS W. L.

2000-01-01

Characteristics of annular wire-array z-pinches as a function of wire number and at high wire number are reviewed. The data, taken primarily using aluminum wires on Saturn are comprehensive. The experiments have provided important insights into the features of wire-array dynamics critical for high x-ray power generation, and have initiated a renaissance in z-pinches when high numbers of wires are used. In this regime, for example, radiation environments characteristic of those encountered during the early pulses required for indirect-drive ICF ignition on the NIF have been produced in hohlraums driven by x-rays from a z-pinch, and are commented on here

Diagnostics for exploding wires (abstract)

International Nuclear Information System (INIS)

Moosman, B.; Bystritskii, V.; Wessel, F.J.; Van Drie, A.

1999-01-01

Two diagnostics, capable of imaging fast, high temperature, plasmas were used on exploding wire experiments at UC Irvine. An atmospheric pressure nitrogen laser (λ=337.1 nm) was used to generate simultaneous shadow and shearing interferogram images with a temporal resolution of ∼1 ns and a spatial resolution of 10 μm. An x-ray backlighter imaged the exploding wire 90 degree with respect to the laser and at approximately the same instant in time. The backlighter spatial resolution as determined by geometry and film resolution was 25 μm. Copper wires of diameters (25, 50, and 100 μm) and steel wire d=25 μm were exploded in vacuum (10 -5 Torr) at a maximum current level of 12 kA, by a rectified marx bank at a voltage of 50 kV and a current rise time (quarter period) of 900 ns. Copper wires which were cleaned and then resistively heated under vacuum to incandescence for several hours prior to high current initiation, exhibited greater expansion velocities at peak current than wires which had not been heated prior to discharge. Axial variations on the surface of the wire observed with the laser were found to correlate with bulk axial mass differences from x-ray backlighting. High electron density, measured near the opaque surface of the exploding wire, suggests that much of the current is shunted outward away from the bulk of the wire. copyright 1999 American Institute of Physics

How flatbed scanners upset accurate film dosimetry

Science.gov (United States)

van Battum, L. J.; Huizenga, H.; Verdaasdonk, R. M.; Heukelom, S.

2016-01-01

Film is an excellent dosimeter for verification of dose distributions due to its high spatial resolution. Irradiated film can be digitized with low-cost, transmission, flatbed scanners. However, a disadvantage is their lateral scan effect (LSE): a scanner readout change over its lateral scan axis. Although anisotropic light scattering was presented as the origin of the LSE, this paper presents an alternative cause. Hereto, LSE for two flatbed scanners (Epson 1680 Expression Pro and Epson 10000XL), and Gafchromic film (EBT, EBT2, EBT3) was investigated, focused on three effects: cross talk, optical path length and polarization. Cross talk was examined using triangular sheets of various optical densities. The optical path length effect was studied using absorptive and reflective neutral density filters with well-defined optical characteristics (OD range 0.2-2.0). Linear polarizer sheets were used to investigate light polarization on the CCD signal in absence and presence of (un)irradiated Gafchromic film. Film dose values ranged between 0.2 to 9 Gy, i.e. an optical density range between 0.25 to 1.1. Measurements were performed in the scanner’s transmission mode, with red-green-blue channels. LSE was found to depend on scanner construction and film type. Its magnitude depends on dose: for 9 Gy increasing up to 14% at maximum lateral position. Cross talk was only significant in high contrast regions, up to 2% for very small fields. The optical path length effect introduced by film on the scanner causes 3% for pixels in the extreme lateral position. Light polarization due to film and the scanner’s optical mirror system is the main contributor, different in magnitude for the red, green and blue channel. We concluded that any Gafchromic EBT type film scanned with a flatbed scanner will face these optical effects. Accurate dosimetry requires correction of LSE, therefore, determination of the LSE per color channel and dose delivered to the film.

How flatbed scanners upset accurate film dosimetry

International Nuclear Information System (INIS)

Van Battum, L J; Verdaasdonk, R M; Heukelom, S; Huizenga, H

2016-01-01

Film is an excellent dosimeter for verification of dose distributions due to its high spatial resolution. Irradiated film can be digitized with low-cost, transmission, flatbed scanners. However, a disadvantage is their lateral scan effect (LSE): a scanner readout change over its lateral scan axis. Although anisotropic light scattering was presented as the origin of the LSE, this paper presents an alternative cause. Hereto, LSE for two flatbed scanners (Epson 1680 Expression Pro and Epson 10000XL), and Gafchromic film (EBT, EBT2, EBT3) was investigated, focused on three effects: cross talk, optical path length and polarization. Cross talk was examined using triangular sheets of various optical densities. The optical path length effect was studied using absorptive and reflective neutral density filters with well-defined optical characteristics (OD range 0.2–2.0). Linear polarizer sheets were used to investigate light polarization on the CCD signal in absence and presence of (un)irradiated Gafchromic film. Film dose values ranged between 0.2 to 9 Gy, i.e. an optical density range between 0.25 to 1.1. Measurements were performed in the scanner’s transmission mode, with red–green–blue channels. LSE was found to depend on scanner construction and film type. Its magnitude depends on dose: for 9 Gy increasing up to 14% at maximum lateral position. Cross talk was only significant in high contrast regions, up to 2% for very small fields. The optical path length effect introduced by film on the scanner causes 3% for pixels in the extreme lateral position. Light polarization due to film and the scanner’s optical mirror system is the main contributor, different in magnitude for the red, green and blue channel. We concluded that any Gafchromic EBT type film scanned with a flatbed scanner will face these optical effects. Accurate dosimetry requires correction of LSE, therefore, determination of the LSE per color channel and dose delivered to the film. (paper)

Self-Catalyzed CdTe Wires

Directory of Open Access Journals (Sweden)

Tom Baines

2018-04-01

Full Text Available CdTe wires have been fabricated via a catalyst free method using the industrially scalable physical vapor deposition technique close space sublimation. Wire growth was shown to be highly dependent on surface roughness and deposition pressure, with only low roughness surfaces being capable of producing wires. Growth of wires is highly (111 oriented and is inferred to occur via a vapor-solid-solid growth mechanism, wherein a CdTe seed particle acts to template the growth. Such seed particles are visible as wire caps and have been characterized via energy dispersive X-ray analysis to establish they are single phase CdTe, hence validating the self-catalysation route. Cathodoluminescence analysis demonstrates that CdTe wires exhibited a much lower level of recombination when compared to a planar CdTe film, which is highly beneficial for semiconductor applications.

Was the Scanner Calibration Slide used for its intended purpose?

Directory of Open Access Journals (Sweden)

Zong Yaping

2011-04-01

Full Text Available Abstract In the article, Scanner calibration revisited, BMC Bioinformatics 2010, 11:361, Dr. Pozhitkov used the Scanner Calibration Slide, a key product of Full Moon BioSystems to generate data in his study of microarray scanner PMT response and proposed a mathematic model for PMT response 1. In the end, the author concluded that "Full Moon BioSystems calibration slides are inadequate for performing calibration," and recommended "against using these slides." We found these conclusions are seriously flawed and misleading, and his recommendation against using the Scanner Calibration Slide was not properly supported.

Practical wiring in SI units

CERN Document Server

Miller, Henry A

2013-01-01

Practical Wiring, Volume 1 is a 13-chapter book that first describes some of the common hand tools used in connection with sheathed wiring. Subsequent chapters discuss the safety in wiring, cables, conductor terminations, insulating sheathed wiring, conductor sizes, and consumer's control equipments. Other chapters center on socket outlets, plugs, lighting subcircuits, lighting accessories, bells, and primary and secondary cells. This book will be very valuable to students involved in this field of interest.

Wire EDM for Refractory Materials

Science.gov (United States)

Zellars, G. R.; Harris, F. E.; Lowell, C. E.; Pollman, W. M.; Rys, V. J.; Wills, R. J.

1982-01-01

In an attempt to reduce fabrication time and costs, Wire Electrical Discharge Machine (Wire EDM) method was investigated as tool for fabricating matched blade roots and disk slots. Eight high-strength nickel-base superalloys were used. Computer-controlled Wire EDM technique provided high quality surfaces with excellent dimensional tolerances. Wire EDM method offers potential for substantial reductions in fabrication costs for "hard to machine" alloys and electrically conductive materials in specific high-precision applications.

Characterization of very high frequency transducers with wire target and hydrophone

International Nuclear Information System (INIS)

Huang Bin; Shung, K Kik

2004-01-01

In this paper, the wire-target technique will be shown to be a useful alternative for beam profile measurements in very high frequency range (30-60 MHz). A 9 cm long tungsten wire with a diameter of 8 μm was used as the pulse-echo target to measure the lateral beam profiles at the focal points of two transducers, a spherically focused 40 MHz Panametrics transducer with an aperture size of 6.35 mm and a geometrical focal length of 12.7 mm and a lense-focused in-house lithium niobate (LiNbO 3 ) 60 MHz transducer with an aperture size of 2 mm and a geometrical focal length around 6.5 mm. For comparison, measurements on the same transducers were performed by three small-aperture hydrophones. The first one is a polyvinylidene fluoride trifluoroethylene (PVDF-TrFE) membrane hydrophone developed by Hewlett-Packard, which has a geometric diameter of 37 μm, a measured effective diameter of less than 100 μm and a -3 dB bandwidth of more than 150 MHz. The second one is a needle-type PVDF hydrophone from Precision Acoustics, which has a 9 μm-thick PVDF element, a 40 μm geometrical aperture and a measured effective diameter of less than 100 μm. The third one is a needle-type PVDF hydrophone from Onda, which has a 150 μm geometrical aperture and an effective diameter of about 180 μm. Experimental results show that the -6 dB two-way beam widths measured by this 8 μm wire-target are in agreement with -3 dB transmitted beam widths measured by small-aperture hydrophones. Compared to small-aperture hydrophones, the wire-target technique is simpler and more cost-effective. Its major advantage however is in the frequency range above 100 MHz in which commercial hydrophones are not yet available

Audio wiring guide how to wire the most popular audio and video connectors

CERN Document Server

Hechtman, John

2012-01-01

Whether you're a pro or an amateur, a musician or into multimedia, you can't afford to guess about audio wiring. The Audio Wiring Guide is a comprehensive, easy-to-use guide that explains exactly what you need to know. No matter the size of your wiring project or installation, this handy tool provides you with the essential information you need and the techniques to use it. Using The Audio Wiring Guide is like having an expert at your side. By following the clear, step-by-step directions, you can do professional-level work at a fraction of the cost.

Scanner qualification with IntenCD based reticle error correction

Science.gov (United States)

Elblinger, Yair; Finders, Jo; Demarteau, Marcel; Wismans, Onno; Minnaert Janssen, Ingrid; Duray, Frank; Ben Yishai, Michael; Mangan, Shmoolik; Cohen, Yaron; Parizat, Ziv; Attal, Shay; Polonsky, Netanel; Englard, Ilan

2010-03-01

Scanner introduction into the fab production environment is a challenging task. An efficient evaluation of scanner performance matrices during factory acceptance test (FAT) and later on during site acceptance test (SAT) is crucial for minimizing the cycle time for pre and post production-start activities. If done effectively, the matrices of base line performance established during the SAT are used as a reference for scanner performance and fleet matching monitoring and maintenance in the fab environment. Key elements which can influence the cycle time of the SAT, FAT and maintenance cycles are the imaging, process and mask characterizations involved with those cycles. Discrete mask measurement techniques are currently in use to create across-mask CDU maps. By subtracting these maps from their final wafer measurement CDU map counterparts, it is possible to assess the real scanner induced printed errors within certain limitations. The current discrete measurement methods are time consuming and some techniques also overlook mask based effects other than line width variations, such as transmission and phase variations, all of which influence the final printed CD variability. Applied Materials Aera2TM mask inspection tool with IntenCDTM technology can scan the mask at high speed, offer full mask coverage and accurate assessment of all masks induced source of errors simultaneously, making it beneficial for scanner qualifications and performance monitoring. In this paper we report on a study that was done to improve a scanner introduction and qualification process using the IntenCD application to map the mask induced CD non uniformity. We will present the results of six scanners in production and discuss the benefits of the new method.

Polar measurements on profiles

Energy Technology Data Exchange (ETDEWEB)

Althaus, D.

1985-03-01

Wind tunnel models with a profile depth of t=0.5 m were measured in a laminar wind tunnel by the usual measuring processes. The profile resistance was determined by integration along the width of span. The smooth profiles were examined at Re=0.7/1.0 and 1.5 million. At Re=1.0 million, the position of the changeover points were determined with a stethoscope. Also at this Reynolds number measurements were taken with a trip wire of d=2 mm diameter, directly on the profile nose. The tables contain the co-ordinates of the profiles, the contours, the theoretical speed distributions for 4 different angles of attack, the csub(a)-csub(w) polar measurements and changeover points, and the torque coefficients around the t/4 point. (BR).

Simple beam profile monitor

Energy Technology Data Exchange (ETDEWEB)

Gelbart, W.; Johnson, R. R.; Abeysekera, B. [ASD Inc. Garden Bay, BC (Canada); Best Theratronics Ltd Ottawa Ontario (Canada); PharmaSpect Ltd., Burnaby BC (Canada)

2012-12-19

An inexpensive beam profile monitor is based on the well proven rotating wire method. The monitor can display beam position and shape in real time for particle beams of most energies and beam currents up to 200{mu}A. Beam shape, position cross-section and other parameters are displayed on a computer screen.

Low power consumption mini rotary actuator with SMA wires

Science.gov (United States)

Manfredi, Luigi; Huan, Yu; Cuschieri, Alfred

2017-11-01

Shape memory alloys (SMAs) are smart materials widely used as actuators for their high power to weight ratio despite their well-known low energy efficiency and limited mechanical bandwidth. For robotic applications, SMAs exhibit limitations due to high power consumption and limited stroke, varying from 4% to 7% of the total length. Hysteresis, during the contraction and extension cycle, requires a complex control algorithm. On the positive side, the small size and low weight are eminently suited for the design of mini actuators for robotic platforms. This paper describes the design and construction of a light weight and low power consuming mini rotary actuator with on-board contact-less position and force sensors. The design is specifically intended to reduce (i) energy consumption, (ii) dimensions of the sensory system, and (iii) provide a simple control without any need for SMA characterisation. The torque produced is controlled by on-board force sensors. Experiments were performed to investigate the energy consumption and performance (step and sinusoidal angle profiles with a frequency varying from 0.5 to 10 Hz and maximal amplitude of {15}\\circ ). We describe a transient capacitor effect related to the SMA wires during the sinusoidal profile when the active SMA wire is powered and the antagonist one switched-off, resulting in a transient current time varying from 300 to 400 ms.

K-wire and tension band wire fixation in treating sternoclavicular joint dislocation

Directory of Open Access Journals (Sweden)

CHEN Qing-yu

2011-02-01

Full Text Available 【Abstract】Objective: To evaluate the feasibility and therapeutic effect of treating sternoclavicular joint dislocation by K-wire and tension band wire fixation, and to improve the safety and stability of this technique. Methods: This study consisted of 9 cases, 6 males and 3 females with the mean age of 25 years (range, 9-62 years. The causes were traffic accident in 7 cases, falling in 1 case and fight in 1 case. The duration from injury to operation was 2 hours to 7 days. There were 5 left dislocations and 4 right dislocations; 8 anterior dislocations and 1 posterior dislocation, including one combined with left scapular fracture and one with left olecranon fracture. Open reduction and internal fixation using K-wires and tension band wires were performed to treat dislocations. Results: All patients were followed up for 6 to 24 months, 10 months on average. According to Rockwood’s rating scale on postoperative sternoclavicular joint, 8 cases achieved excellent outcomes with an average score of 13.88, and the rest case achieved a good outcome with the score of 12. Anatomical reduction was obtained in all cases. There were no such postoperative complications as severe infection, injury to blood vessel and nerve, failure of fixation, etc. Patients were all satisfied with the anatomical reduction and functional recovery. Conclusions: The technique of K-wire and tension band wire fixation is safe, simple, effective, less invasive and has been successfully used in orthopedic surgery. It is effective in treating sternoclavicular joint dislocation though it has some disadvantages. Key words: Sternoclavicular joint; Dislocations; Bone wires; Fracture fixation, internal

Vision Assisted Laser Scanner Navigation for Autonomous Robots

DEFF Research Database (Denmark)

Andersen, Jens Christian; Andersen, Nils Axel; Ravn, Ole

2008-01-01

This paper describes a navigation method based on road detection using both a laser scanner and a vision sensor. The method is to classify the surface in front of the robot into traversable segments (road) and obstacles using the laser scanner, this classifies the area just in front of the robot ...

A comparison of a 'J' wire and a straight wire in successful antegrade cannulation of the superficial femoral artery

International Nuclear Information System (INIS)

Gay, D.A.T.; Edwards, A.J.; Puckett, M.A.; Roobottom, C.A.

2005-01-01

AIMS: To evaluate the success of two different types of wire in common use in their ability to successfully cannulate the superficial femoral artery (SFA) using antegrade puncture. METHODS: 50 consecutive patients in whom antegrade infra-inguinal intervention was planned, underwent common femoral arterial puncture and then cannulation with either a standard 3 mm 'J' wire or a floppy tipped straight wire (William Cook--Europe). The frequency with which each type of wire entered the SFA or profunda femoris artery without image guidance was recorded. Further analysis was also made of the success of manipulation of the wire into the SFA following profunda cannulation and the use of alternative guide wires. RESULTS: In 19 out of 25 (76%) patients the 'J' wire correctly entered the SFA without image guidance. Only 5 out of 25 (25%) of straight wires entered the SFA with the initial pass (p<0.0001). Following further manipulation with the same wire all except 1 'J' wire was successfully negotiated into the SFA. The same was true for only 9 of the remaining straight wires with 11 patients requiring an alternative guide wire. CONCLUSIONS: When performing antegrade cannulation of the SFA a 'J' wire is more likely to be successful than a straight guide wire

Arc Interference Behavior during Twin Wire Gas Metal Arc Welding Process

Directory of Open Access Journals (Sweden)

Dingjian Ye

2013-01-01

Full Text Available In order to study arc interference behavior during twin wire gas metal arc welding process, the synchronous acquisition system has been established to acquire instantaneous information of arc profile including dynamic arc length variation as well as relative voltage and current signals. The results show that after trailing arc (T-arc is added to the middle arc (M-arc in a stable welding process, the current of M arc remains unchanged while the agitation increases; the voltage of M arc has an obvious increase; the shape of M arc changes, with increasing width, length, and area; the transfer frequency of M arc droplet increases and the droplet itself becomes smaller. The wire extension length of twin arc turns out to be shorter than that of single arc welding.

Validated finite element analyses of WaveOne Endodontic Instruments: a comparison between M-Wire and NiTi alloys.

Science.gov (United States)

Bonessio, N; Pereira, E S J; Lomiento, G; Arias, A; Bahia, M G A; Buono, V T L; Peters, O A

2015-05-01

To validate torsional analysis, based on finite elements, of WaveOne instruments against in vitro tests and to model the effects of different nickel-titanium (NiTi) materials. WaveOne reciprocating instruments (Small, Primary and Large, n = 8 each, M-Wire) were tested under torsion according to standard ISO 3630-1. Torsional profiles including torque and angle at fracture were determined. Test conditions were reproduced through Finite Element Analysis (FEA) simulations based on micro-CT scans at 10-μm resolution; results were compared to experimental data using analysis of variance and two-sided one sample t-tests. The same simulation was performed on virtual instruments with identical geometry and load condition, based on M-Wire or conventional NiTi alloy. Torsional profiles from FEA simulations were in significant agreement with the in vitro results. Therefore, the models developed in this study were accurate and able to provide reliable simulation of the torsional performance. Stock NiTi files under torsional tests had up to 44.9%, 44.9% and 44.1% less flexibility than virtual M-Wire files at small deflections for Small, Primary and Large instruments, respectively. As deflection levels increased, the differences in flexibility between the two sets of simulated instruments decreased until fracture. Stock NiTi instruments had a torsional fracture resistance up to 10.3%, 8.0% and 7.4% lower than the M-Wire instruments, for the Small, Primary and Large file, respectively. M-Wire instruments benefitted primarily through higher material flexibility while still at low deflection levels, compared with conventional NiTi alloy. At fracture, the instruments did not take complete advantage of the enhanced fractural resistance of the M-Wire material, which determines only limited improvements of the torsional performance. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

The Analysis of the High Speed Wire Drawing Process of High Carbon Steel Wires Under Hydrodynamic Lubrication Conditions

Directory of Open Access Journals (Sweden)

Suliga M.

2015-04-01

Full Text Available In this work the analysis of the wire drawing process in hydrodynamic dies has been done. The drawing process of φ5.5 mm wire rod to the final wire of φ1.7 mm was conducted in 12 passes, in drawing speed range of 5-25 m/s. For final wires of φ1.7 mm the investigation of topography of wire surface, the amount of lubricant on the wire surface and the pressure of lubricant in hydrodynamic dies were determined. Additionally, in the work selected mechanical properties of the wires have been estimated.

Towards plant wires.

Science.gov (United States)

Adamatzky, Andrew

2014-08-01

In experimental laboratory studies we evaluate a possibility of making electrical wires from living plants. In scoping experiments we use lettuce seedlings as a prototype model of a plant wire. We approximate an electrical potential transfer function by applying direct current voltage to the lettuce seedlings and recording output voltage. We analyse oscillation frequencies of the output potential and assess noise immunity of the plant wires. Our findings will be used in future designs of self-growing wetware circuits and devices, and integration of plant-based electronic components into future and emergent bio-hybrid systems. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Comparison of two intraoral scanners based on three-dimensional surface analysis

Directory of Open Access Journals (Sweden)

Kyung-Min Lee

2018-02-01

Full Text Available Abstract Background This in vivo study evaluated the difference of two well-known intraoral scanners used in dentistry, namely iTero (Align Technology and TRIOS (3Shape. Methods Thirty-two participants underwent intraoral scans with TRIOS and iTero scanners, as well as conventional alginate impressions. The scans obtained with the two intraoral scanners were compared with each other and were also compared with the corresponding model scans by means of three-dimensional surface analysis. The average differences between the two intraoral scans on the surfaces were evaluated by color-mapping. The average differences in the three-dimensional direction between each intraoral scans and its corresponding model scan were calculated at all points on the surfaces. Results The average differences between the two intraoral scanners were 0.057 mm at the maxilla and 0.069 mm at the mandible. Color histograms showed that local deviations between the two scanners occurred in the posterior area. As for difference in the three-dimensional direction, there was no statistically significant difference between two scanners. Conclusions Although there were some deviations in visible inspection, there was no statistical significance between the two intraoral scanners.

Ionization beam scanner

CERN Multimedia

CERN PhotoLab

1973-01-01

Inner structure of an ionization beam scanner, a rather intricate piece of apparatus which permits one to measure the density distribution of the proton beam passing through it. On the outside of the tank wall there is the coil for the longitudinal magnetic field, on the inside, one can see the arrangement of electrodes creating a highly homogeneous transverse electric field.

Quality assurance of computed tomography (CT) scanners

International Nuclear Information System (INIS)

Sankaran, A.; Sanu, K.K. . Email : a_sankaran@vsnl.com

2004-01-01

This article reviews the present status of research work and development of various test objects, phantoms and detector/instrumentation systems for quality assurance (QA) of computed tomography (CT) scanners, carried out in advanced countries, with emphasis on similar work done in this research centre. CT scanner is a complex equipment and routine quality control procedures are essential to the maintenance of image quality with optimum patient dose. Image quality can be ensured only through correlation between prospective monitoring of system components and tests of overall performance with standard phantoms. CT examinations contribute a large share to the population dose in advanced countries. The unique dosimetry problems in CT necessitate special techniques. This article describes a comprehensive kit developed indigenously for the following QA and type approval tests as well as for research studies on image quality/dosimetry on CT scanners

Contrast-to-noise ratio optimization for a prototype phase-contrast computed tomography scanner

International Nuclear Information System (INIS)

Müller, Mark; Yaroshenko, Andre; Velroyen, Astrid; Tapfer, Arne; Bech, Martin; Pauwels, Bart; Bruyndonckx, Peter; Sasov, Alexander; Pfeiffer, Franz

2015-01-01

In the field of biomedical X-ray imaging, novel techniques, such as phase-contrast and dark-field imaging, have the potential to enhance the contrast and provide complementary structural information about a specimen. In this paper, a first prototype of a preclinical X-ray phase-contrast CT scanner based on a Talbot-Lau interferometer is characterized. We present a study of the contrast-to-noise ratios for attenuation and phase-contrast images acquired with the prototype scanner. The shown results are based on a series of projection images and tomographic data sets of a plastic phantom in phase and attenuation-contrast recorded with varying acquisition settings. Subsequently, the signal and noise distribution of different regions in the phantom were determined. We present a novel method for estimation of contrast-to-noise ratios for projection images based on the cylindrical geometry of the phantom. Analytical functions, representing the expected signal in phase and attenuation-contrast for a circular object, are fitted to individual line profiles of the projection data. The free parameter of the fit function is used to estimate the contrast and the goodness of the fit is determined to assess the noise in the respective signal. The results depict the dependence of the contrast-to-noise ratios on the applied source voltages, the number of steps of the phase stepping routine, and the exposure times for an individual step. Moreover, the influence of the number of projection angles on the image quality of CT slices is investigated. Finally, the implications for future imaging purposes with the scanner are discussed

Single and nested tungsten-wire-array dynamics and applications to inertial confinement fusion

Science.gov (United States)

Cuneo, Michael

2005-10-01

Wire array z-pinches show great promise as x-ray sources for indirect-drive inertial confinement fusion (ICF). The double z-pinch hohlraum, for example, has produced capsule radiation drive symmetric to within 3%. This ICF concept will require that each of two 20-mm-diam arrays scale to x-ray powers ˜1 PW, to drive high-yield (>0.2 GJ) capsules to ignition. High-yield fusion will also require a temporally shaped radiation pulse to drive a low-entropy capsule implosion. Recently, improved understanding of high current (11-19 MA) single and nested wire-array dynamics has enabled significant progress towards these goals. As at lower currents, a single wire array (and both the outer and inner arrays of a nested system) shows a wire ablation phase, axial modulation of the ablation rate, a larger ablation rate for larger diameter wires, trailing mass and trailing current. These processes and others produce a broad mass profile that may impact the optimization of x-ray output for single and nested arrays. Our new insights into wire array physics have led to 20-mm-diam single and nested arrays with peak powers of 150-190 TW at implosion times of 55-90 ns, increased from 60-120 TW at 95-110 ns, improving power scaling. Radiation pulse shapes required for 3-shock isentropic compression of high-yield ICF capsules have also been demonstrated with nested wire arrays operating in current-transfer mode. In collaboration with: D.B. Sinars, R.A. Vesey, E.M. Waisman, W.A. Stygar, D.E. Bliss, S.V. Lebedev, J.P. Chittenden, P.V. Sasorov, R.W. Lemke, E.P. Yu, B.B. Afeyan, G.R. Bennett, M.G. Mazarakis, M.R. Lopez, M.E. Savage, J.L. Porter, T.A. Mehlhorn.

Metallurgical characterization of controlled memory wire nickel-titanium rotary instruments.

Science.gov (United States)

Shen, Ya; Zhou, Hui-Min; Zheng, Yu-Feng; Campbell, Les; Peng, Bin; Haapasalo, Markus

2011-11-01

To improve the fracture resistance of nickel-titanium (NiTi) files, manufacturers have introduced new alloys and developed new manufacturing processes for the fabrication of NiTi files. This study aimed to examine the phase transformation behavior and microstructure of NiTi instruments from a novel controlled memory NiTi wire (CM wire). Instruments of EndoSequence (ES), ProFile (PF), ProFile Vortex (Vortex), Twisted Files (TF), Typhoon (TYP), and Typhoon™ CM (TYP CM), all size 25/.04, were examined by differential scanning calorimetry (DSC) and x-ray diffraction (XRD). Microstructures of etched instruments were observed by optical microscopy and scanning electron microscopy with x-ray energy-dispersive spectrometric (EDS) analyses. The DSC analyses showed that each segment of the TYP CM and Vortex instruments had an austenite transformation completion or austenite-finish (A(f)) temperature exceeding 37°C, whereas the NiTi instruments made from conventional superelastic NiTi wire (ES, PF, and TYP) and TF had A(f) temperatures substantially below mouth temperature. The higher A(f) temperature of TYP CM instruments was consistent with a mixture of austenite and martensite structure, which was observed at room temperature with XRD. All NiTi instruments had room temperature martensite microstructures consisting of colonies of lenticular features with substantial twinning. EDS analysis indicated that the precipitates in all NiTi instruments were titanium-rich, with an approximate composition of Ti(2)Ni. The TYP CM and Vortex instruments with heat treatment contribute to increase austenite transformation temperature. The CM instrument has significant changes in the phase transformation behavior, compared with conventional superelastic NiTi instruments. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Investigation of method for Stainless Steel Welding Wire as a Replacement for Arc Wire Comsumables

Directory of Open Access Journals (Sweden)

Koiprasert, H.

2005-01-01

Full Text Available Arc spraying as a coating method is being employed in various industrial applications as a part of maintenance service, and also as a surface engineering technique for many machine parts and components. The major cost in producing the arc spray coating is, however, based on the cost of the arc wire comsumables. This project was carried out to investigate the use of the commercially-available gas metal arc welding wire (GMAW wire as a cheaper alternative to the special-purpose arc wire comsumables. The wire material chosen for this early study is the 316L stainless steel, due to its popularity in many applications as a built-up coating for worn parts. The physical properties of the coatings produced from the two sets of 316L stainless steel wire were determined to be different in the percentage of porosity and the oxide content. The mechanical properties, including the tensile bond strength and the wear rate of the coatings produced from the two types of sprayed wire, were also different. This will, in turn, result in a slight difference in the performance of thecoatings.

Welding wire pressure sensor assembly

Science.gov (United States)

Morris, Timothy B. (Inventor); Milly, Peter F., Sr. (Inventor); White, J. Kevin (Inventor)

1994-01-01

The present invention relates to a device which is used to monitor the position of a filler wire relative to a base material being welded as the filler wire is added to a welding pool. The device is applicable to automated welding systems wherein nonconsumable electrode arc welding processes are utilized in conjunction with a filler wire which is added to a weld pool created by the electrode arc. The invention senses pressure deviations from a predetermined pressure between the filler wire and the base material, and provides electrical signals responsive to the deviations for actuating control mechanisms in an automatic welding apparatus so as to minimize the pressure deviation and to prevent disengagement of the contact between the filler wire and the base material.

A LIDAR-Based Tree Canopy Characterization under Simulated Uneven Road Condition: Advance in Tree Orchard Canopy Profile Measurement

Directory of Open Access Journals (Sweden)

Yue Shen

2017-01-01

Full Text Available In real outdoor canopy profile detection, the accuracy of a LIDAR scanner to measure canopy structure is affected by a potentially uneven road condition. The level of error associated with attitude angles from undulations in the ground surface can be reduced by developing appropriate correction algorithm. This paper proposes an offline attitude angle offset correction algorithm based on a 3D affine coordinate transformation. The validity of the correction algorithm is verified by conducting an indoor experiment. The experiment was conducted on an especially designed canopy profile measurement platform. During the experiment, an artificial tree and a tree-shaped carved board were continuously scanned at constant laser scanner travel speed and detection distances under simulated bumpy road conditions. Acquired LIDAR laser scanner raw data was processed offline by exceptionally developed MATLAB program. The obtained results before and after correction method show that the single attitude angle offset correction method is able to correct the distorted data points in tree-shaped carved board profile measurement, with a relative error of 5%, while the compound attitude angle offset correction method is effective to reduce the error associated with compound attitude angle deviation from the ideal scanner pose, with relative error of 7%.

A LabVIEW® based generic CT scanner control software platform.

Science.gov (United States)

Dierick, M; Van Loo, D; Masschaele, B; Boone, M; Van Hoorebeke, L

2010-01-01

UGCT, the Centre for X-ray tomography at Ghent University (Belgium) does research on X-ray tomography and its applications. This includes the development and construction of state-of-the-art CT scanners for scientific research. Because these scanners are built for very different purposes they differ considerably in their physical implementations. However, they all share common principle functionality. In this context a generic software platform was developed using LabVIEW® in order to provide the same interface and functionality on all scanners. This article describes the concept and features of this software, and its potential for tomography in a research setting. The core concept is to rigorously separate the abstract operation of a CT scanner from its actual physical configuration. This separation is achieved by implementing a sender-listener architecture. The advantages are that the resulting software platform is generic, scalable, highly efficient, easy to develop and to extend, and that it can be deployed on future scanners with minimal effort.

Evaluation of PeneloPET Simulations of Biograph PET/CT Scanners

Science.gov (United States)

Abushab, K. M.; Herraiz, J. L.; Vicente, E.; Cal-González, J.; España, S.; Vaquero, J. J.; Jakoby, B. W.; Udías, J. M.

2016-06-01

Monte Carlo (MC) simulations are widely used in positron emission tomography (PET) for optimizing detector design, acquisition protocols, and evaluating corrections and reconstruction methods. PeneloPET is a MC code based on PENELOPE, for PET simulations which considers detector geometry, acquisition electronics and materials, and source definitions. While PeneloPET has been successfully employed and validated with small animal PET scanners, it required a proper validation with clinical PET scanners including time-of-flight (TOF) information. For this purpose, we chose the family of Biograph PET/CT scanners: the Biograph True-Point (B-TP), Biograph True-Point with TrueV (B-TPTV) and the Biograph mCT. They have similar block detectors and electronics, but a different number of rings and configuration. Some effective parameters of the simulations, such as the dead-time and the size of the reflectors in the detectors, were adjusted to reproduce the sensitivity and noise equivalent count (NEC) rate of the B-TPTV scanner. These parameters were then used to make predictions of experimental results such as sensitivity, NEC rate, spatial resolution, and scatter fraction (SF), from all the Biograph scanners and some variations of them (energy windows and additional rings of detectors). Predictions agree with the measured values for the three scanners, within 7% (sensitivity and NEC rate) and 5% (SF). The resolution obtained for the B-TPTV is slightly better (10%) than the experimental values. In conclusion, we have shown that PeneloPET is suitable for simulating and investigating clinical systems with good accuracy and short computational time, though some effort tuning of a few parameters of the scanners modeled may be needed in case that the full details of the scanners studied are not available.

Resuscitative endovascular balloon occlusion of the aorta with a low profile, wire free device: A game changer?

Directory of Open Access Journals (Sweden)

James N. Bogert

2017-02-01

Full Text Available A 24 year old male arrived to our hospital after a motor cycle crash with evidence of a traumatic brain injury and in hemorrhagic shock not responsive to volume administration. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA was performed in a timely fashion using a new, low profile, wire free device. This lead to rapid reversal of hypotension while his bleeding source was sought and controlled.Recently, REBOA has emerged as an adjunct in the hypotensive trauma patient with noncompressible torso hemorrhage. As first described, this procedure makes use of commonly available vascular surgery and endovascular products requiring large introducer sheaths (12–14 French and long guidewires. Concerns regarding this technique center around the safety and feasibility of using such equipment in the emergency setting outside an angiography suite. This has likely limited widespread adoption of this technique. To address these concerns, newer products designed to be placed through a smaller sheath (7 French and without the use of guidewires have been developed. Here we report on our first clinical use of such a device that we believe represents a significant advance in the care of the trauma patient. Keywords: REBOA, Resuscitation, Hemorrhage, Endovascular

Radiation dosimetry of computed tomography x-ray scanners

International Nuclear Information System (INIS)

Poletti, J.L.; Williamson, B.D.P.; Le Heron, J.C.

1983-01-01

This report describes the development and application of the methods employed in National Radiation Laboratory (NRL) surveys of computed tomography x-ray scanners (CT scanners). It includes descriptions of the phantoms and equipment used, discussion of the various dose parameters measured, the principles of the various dosimetry systems employed and some indication of the doses to occupationally exposed personnel

Study of ablation and implosion stages in wire arrays using coupled ultraviolet and X-ray probing diagnostics

Energy Technology Data Exchange (ETDEWEB)

Anderson, A. A.; Ivanov, V. V.; Astanovitskiy, A. L.; Wiewior, P. P.; Chalyy, O. [University of Nevada Reno, Reno, Nevada 89557 (United States); Papp, D. [University of Nevada Reno, Reno, Nevada 89557 (United States); ELI-ALPS, ELI-Hu Nkft., H-6720 Szeged (Hungary)

2015-11-15

Star and cylindrical wire arrays were studied using laser probing and X-ray radiography at the 1-MA Zebra pulse power generator at the University of Nevada, Reno. The Leopard laser provided backlighting, producing a laser plasma from a Si target which emitted an X-ray probing pulse at the wavelength of 6.65 Å. A spherically bent quartz crystal imaged the backlit wires onto X-ray film. Laser probing diagnostics at the wavelength of 266 nm included a 3-channel polarimeter for Faraday rotation diagnostic and two-frame laser interferometry with two shearing interferometers to study the evolution of the plasma electron density at the ablation and implosion stages. Dynamics of the plasma density profile in Al wire arrays at the ablation stage were directly studied with interferometry, and expansion of wire cores was measured with X-ray radiography. The magnetic field in the imploding plasma was measured with the Faraday rotation diagnostic, and current was reconstructed.

Free-space wavelength-multiplexed optical scanner.

Science.gov (United States)

Yaqoob, Z; Rizvi, A A; Riza, N A

2001-12-10

A wavelength-multiplexed optical scanning scheme is proposed for deflecting a free-space optical beam by selection of the wavelength of the light incident on a wavelength-dispersive optical element. With fast tunable lasers or optical filters, this scanner features microsecond domain scan setting speeds and large- diameter apertures of several centimeters or more for subdegree angular scans. Analysis performed indicates an optimum scan range for a given diffraction order and grating period. Limitations include beam-spreading effects based on the varying scanner aperture sizes and the instantaneous information bandwidth of the data-carrying laser beam.

A multiwire secondary emission profile monitor for small emittance beams

International Nuclear Information System (INIS)

Chehab, R.; Bonnard, J.; Humbert, G.; Leblond, B.; Saury, J.L.

1985-01-01

A secondary emission monitor using two multiwire grids separated by a positively biased collector has been constructed and tested with a 1 GeV electron beam at the Orsay Linac. The monitor installed just before the electron-positron converter has 8 gold-plated-tungsten wires of 0.1 mm diameter equally spaced 0.2 mm apart in each plane. Each wire is connected with an integrator using a low-bias current operational amplifier. The wire planes and the collector are moved into the beam by a stepping motor : that allows beam-position verification. We measured narrow profiles for 1 Amp peak current pulses of 30 nanoseconds width. Profiles are displayed on a scope and allow emittance determination by the three gradient method. Such a monitor is very useful to control the electron beam position and dimensions on the converter, because the positron source dimensions are rather bigger than those of the incident beam and the geometrical acceptance of the positron Linac is limited

Miniaturized Fourier-plane fiber scanner for OCT endoscopy

International Nuclear Information System (INIS)

Vilches, Sergio; Kretschmer, Simon; Ataman, Çağlar; Zappe, Hans

2017-01-01

A forward-looking endoscopic optical coherence tomography (OCT) probe featuring a Fourier-plane fiber scanner is designed, manufactured and characterized. In contrast to common image-plane fiber scanners, the Fourier-plane scanner is a telecentric arrangement that eliminates vignetting and spatial resolution variations across the image plane. To scan the OCT beam in a spiral pattern, a tubular piezoelectric actuator is used to resonate an optical fiber bearing a collimating GRIN lens at its tip. The free-end of the GRIN lens sits at the back focal plane of an objective lens, such that its rotation replicates the beam angles in the collimated region of a classical telecentric 4f optical system. Such an optical arrangement inherently has a low numerical aperture combined with a relatively large field-of-view, rendering it particularly useful for endoscopic OCT imaging. Furthermore, the optical train of the Fourier-plane scanner is shorter than that of a comparable image-plane scanner by one focal length of the objective lens, significantly shortening the final arrangement. As a result, enclosed within a 3D printed housing of 2.5 mm outer diameter and 15 mm total length, the developed probe is the most compact forward-looking endoscopic OCT imager to date. Due to its compact form factor and compatibility with real-time OCT imaging, the developed probe is also ideal for use in the working channel of flexible endoscopes as a potential optical biopsy tool. (paper)

Miniaturized Fourier-plane fiber scanner for OCT endoscopy

Science.gov (United States)

Vilches, Sergio; Kretschmer, Simon; Ataman, Çağlar; Zappe, Hans

2017-10-01

A forward-looking endoscopic optical coherence tomography (OCT) probe featuring a Fourier-plane fiber scanner is designed, manufactured and characterized. In contrast to common image-plane fiber scanners, the Fourier-plane scanner is a telecentric arrangement that eliminates vignetting and spatial resolution variations across the image plane. To scan the OCT beam in a spiral pattern, a tubular piezoelectric actuator is used to resonate an optical fiber bearing a collimating GRIN lens at its tip. The free-end of the GRIN lens sits at the back focal plane of an objective lens, such that its rotation replicates the beam angles in the collimated region of a classical telecentric 4f optical system. Such an optical arrangement inherently has a low numerical aperture combined with a relatively large field-of-view, rendering it particularly useful for endoscopic OCT imaging. Furthermore, the optical train of the Fourier-plane scanner is shorter than that of a comparable image-plane scanner by one focal length of the objective lens, significantly shortening the final arrangement. As a result, enclosed within a 3D printed housing of 2.5 mm outer diameter and 15 mm total length, the developed probe is the most compact forward-looking endoscopic OCT imager to date. Due to its compact form factor and compatibility with real-time OCT imaging, the developed probe is also ideal for use in the working channel of flexible endoscopes as a potential optical biopsy tool.

Absolute dosimetric characterization of Gafchromic EBT3 and HDv2 films using commercial flat-bed scanners and evaluation of the scanner response function variability

Energy Technology Data Exchange (ETDEWEB)

Chen, S. N.; Revet, G.; Fuchs, J. [LULI-CNRS, Ecole Polytechnique, CEA: Universite Paris-Saclay, UPMC Univ Paris 06, Sorbonne Universities, F-91128 Palaiseau Cedex (France); Institute of Applied Physics, 46 Ulyanov Street, 603950 Nizhny Novgorod (Russian Federation); Gauthier, M.; Glenzer, S.; Propp, A. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Bazalova-Carter, M. [Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 5C2 (Canada); Bolanos, S. [LULI-CNRS, Ecole Polytechnique, CEA: Universite Paris-Saclay, UPMC Univ Paris 06, Sorbonne Universities, F-91128 Palaiseau Cedex (France); Riquier, R. [LULI-CNRS, Ecole Polytechnique, CEA: Universite Paris-Saclay, UPMC Univ Paris 06, Sorbonne Universities, F-91128 Palaiseau Cedex (France); CEA, DAM, DIF, F-91297 Arpajon (France); Antici, P. [INRS-EMT, Varennes, J3X1S2 Québec (Canada); Morabito, A. [ELI-ALPS, ELI-HU non profit kft, Dugonics ter 13, H-6720, Szeged (Hungary); Starodubtsev, M. [Institute of Applied Physics, 46 Ulyanov Street, 603950 Nizhny Novgorod (Russian Federation)

2016-07-15

Radiochromic films (RCF) are commonly used in dosimetry for a wide range of radiation sources (electrons, protons, and photons) for medical, industrial, and scientific applications. They are multi-layered, which includes plastic substrate layers and sensitive layers that incorporate a radiation-sensitive dye. Quantitative dose can be retrieved by digitizing the film, provided that a prior calibration exists. Here, to calibrate the newly developed EBT3 and HDv2 RCFs from Gafchromic™, we used the Stanford Medical LINAC to deposit in the films various doses of 10 MeV photons, and by scanning the films using three independent EPSON Precision 2450 scanners, three independent EPSON V750 scanners, and two independent EPSON 11000XL scanners. The films were scanned in separate RGB channels, as well as in black and white, and film orientation was varied. We found that the green channel of the RGB scan and the grayscale channel are in fact quite consistent over the different models of the scanner, although this comes at the cost of a reduction in sensitivity (by a factor ∼2.5 compared to the red channel). To allow any user to extend the absolute calibration reported here to any other scanner, we furthermore provide a calibration curve of the EPSON 2450 scanner based on absolutely calibrated, commercially available, optical density filters.

Evaluation of cyclic flexural fatigue of M-wire nickel-titanium rotary instruments.

Science.gov (United States)

Al-Hadlaq, Solaiman M S; Aljarbou, Fahad A; AlThumairy, Riyadh I

2010-02-01

This study was conducted to investigate cyclic flexural fatigue resistance of GT series X rotary files made from the newly developed M-wire nickel-titanium alloy compared with GT and Profile nickel-titanium files made from a conventional nickel-titanium alloy. Fifteen files, size 30/0.04, of each type were used to evaluate the cyclic flexural fatigue resistance. A simple device was specifically constructed to measure the time each file type required to fail under cyclic flexural fatigue testing. The results of this experiment indicated that the GT series X files had superior cyclic flexural fatigue resistance than the other 2 file types made from a conventional nickel-titanium alloy (P = .004). On the other hand, the difference between the Profile and the GT files was not statistically significant. The findings of this study suggest that size 30/0.04 nickel-titanium rotary files made from the newly developed M-wire alloy have better cyclic flexural fatigue resistance than files of similar design and size made from the conventional nickel-titanium alloy. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Evaluation of Handheld Scanners for Automotive Applications

Directory of Open Access Journals (Sweden)

Wadea Ameen

2018-01-01

Full Text Available The process of generating a computerized geometric model for an existing part is known as Reverse Engineering (RE. It is a very useful technique in product development and plays a significant role in automotive, aerospace, and medical industries. In fact, it has been getting remarkable attention in manufacturing industries owing to its advanced data acquisition technologies. The process of RE is based on two primary steps: data acquisition (also known as scanning and data processing. To facilitate point data acquisition, a variety of scanning systems is available with different capabilities and limitations. Although the optical control of 3D scanners is fully developed, still several factors can affect the quality of the scanned data. As a result, the proper selection of scanning parameters, such as resolution, laser power, shutter time, etc., becomes very crucial. This kind of investigation can be very helpful and provide its users with guidelines to identify the appropriate factors. Moreover, it is worth noting that no single system is ideal in all applications. Accordingly, this work has compared two portable (handheld systems based on laser scanning and white light optical scanning for automotive applications. A car door containing a free-form surface has been used to achieve the above-mentioned goal. The design of experiments has been employed to determine the effects of different scanning parameters and optimize them. The capabilities and limitations have been identified by comparing the two scanners in terms of accuracy, scanning time, triangle numbers, ease of use, and portability. Then, the relationships between the system capabilities and the application requirements have been established. The results revealed that the laser scanner performed better than the white light scanner in terms of accuracy, while the white light scanner performed better in terms of acquisition speed and triangle numbers.

Clinical bending of nickel titanium wires

Directory of Open Access Journals (Sweden)

Stephen Chain

2015-01-01

Full Text Available Since the evolution and the involvement of Nickel Titanium wires in the field of Orthodontics. The treatment plan has evolved with the use of low force Nickel Titanium wires. Because of their high springback, low stiffness, they are the key initial wires in leveling and alignment but have poor formability. Since poor formability limits its ability to create variable arch forms thus; limits the form of treatment. We have devised a method to bend the Nickel Titanium wires to help in our inventory but also customized the wire according to the treatment.

An interconnecting bus power optimization method combining interconnect wire spacing with wire ordering

International Nuclear Information System (INIS)

Zhu Zhang-Ming; Hao Bao-Tian; En Yun-Fei; Yang Yin-Tang; Li Yue-Jin

2011-01-01

On-chip interconnect buses consume tens of percents of dynamic power in a nanometer scale integrated circuit and they will consume more power with the rapid scaling down of technology size and continuously rising clock frequency, therefore it is meaningful to lower the interconnecting bus power in design. In this paper, a simple yet accurate interconnect parasitic capacitance model is presented first and then, based on this model, a novel interconnecting bus optimization method is proposed. Wire spacing is a process for spacing wires for minimum dynamic power, while wire ordering is a process that searches for wire orders that maximally enhance it. The method, i.e., combining wire spacing with wire ordering, focuses on bus dynamic power optimization with a consideration of bus performance requirements. The optimization method is verified based on various nanometer technology parameters, showing that with 50% slack of routing space, 25.71% and 32.65% of power can be saved on average by the proposed optimization method for a global bus and an intermediate bus, respectively, under a 65-nm technology node, compared with 21.78% and 27.68% of power saved on average by uniform spacing technology. The proposed method is especially suitable for computer-aided design of nanometer scale on-chip buses. (interdisciplinary physics and related areas of science and technology)

[Practicability of the mobile one-finger scanner Cross Match MV5 in fingerprinting of corpses: are mobile fingerprinting scanners suitable for use in mass disasters?].

Science.gov (United States)

Breitmeier, Dirk; Landmesser, Britta; Schulz, Yvonne; Albrecht, Knut

2008-01-01

Dactyloscopy is a special field in the police records department and a suitable means for identifying unknown dead persons as well as solving crimes by taking fingerprints from living persons. Apart from the conventional methods of dactyloscopy, mobile and more compact instruments are to facilitate taking prints of fingertips and palms also at the scene of mass disasters. In the presented study, living persons and corpses were examined to find out the possible uses and limits of mobile one-finger scanners. The concrete issue of the investigation was whether the mobile one-finger scanner Cross Match MV5 is suitable for application in mass disasters. The device was used in 12 corpses aged 5 weeks to 76 years (mean postmortem interval 5.5 days) and in 28 living persons aged 6 weeks to 87 years. In summary, the scanner produced qualitatively good prints in all age groups of the living individuals. In the corpses, the prints were only partly evaluable. In particular, fingers and fingertips with soot blackening and livid discoloration were difficult to analyse. Postmortem rigidity also complicated the handling of the scanner. In fresh corpses, the scanner can be recommended without reservation. Even if the epidermis was detached, the scanner was able to produce evaluable prints of the dermis of the hypothenar.

K-wire and tension band wire fixation in treating sternoclavicular joint dislocation.

Science.gov (United States)

Chen, Qing-yu; Cheng, Shao-wen; Wang, Wei; Lin, Zhong-qin; Zhang, Wei; Kou, Dong-quan; Shen, Yue; Ying, Xiao-zhou; Cheng, Xiao-jie; Lv, Chuan-zhu; Peng, Lei

2011-02-01

To evaluate the feasibility and therapeutic effect of treating sternoclavicular joint dislocation by K-wire and tension band wire fixation, and to improve the safety and stability of this technique. This study consisted of 9 cases, 6 males and 3 females with the mean age of 25 years (range, 9-62 years). The causes were traffic accident in 7 cases, falling in 1 case and fight in 1 case. The duration from injury to operation was 2 hours to 7 days. There were 5 left dislocations and 4 right dislocations; 8 anterior dislocations and 1 posterior dislocation, including one combined with left scapular fracture and one with left olecranon fracture. Open reduction and internal fixation using K-wires and tension band wires were performed to treat dislocations. All patients were followed up for 6 to 24 months, 10 months on average. According to Rockwood's rating scale on postoperative sternoclavicular joint, 8 cases achieved excellent outcomes with an average score of 13.88, and the rest case achieved a good outcome with the score of 12. Anatomical reduction was obtained in all cases. There were no such postoperative complications as severe infection, injury to blood vessel and nerve, failure of fixation, etc. Patients were all satisfied with the anatomical reduction and functional recovery. The technique of K-wire and tension band wire fixation is safe, simple, effective, less invasive and has been successfully used in orthopedic surgery. It is effective in treating sternoclavicular joint dislocation though it has some disadvantages.

Corrosion behavior of ion implanted nickel-titanium orthodontic wire in fluoride mouth rinse solutions.

Science.gov (United States)

Iijima, Masahiro; Yuasa, Toshihiro; Endo, Kazuhiko; Muguruma, Takeshi; Ohno, Hiroki; Mizoguchi, Itaru

2010-01-01

This study investigated the corrosion properties of ion implanted nickel-titanium wire (Neo Sentalloy Ionguard) in artificial saliva and fluoride mouth rinse solutions (Butler F Mouthrinse, Ora-Bliss). Non ion implanted nickel-titanium wire (Neo Sentalloy) was used as control. The anodic corrosion behavior was examined by potentiodynamic polarization measurement. The surfaces of the specimens were examined with SEM. The elemental depth profiles were characterized by XPS. Neo Sentalloy Ionguard in artificial saliva and Butler F Mouthrinse (500 ppm) had a lower current density than Neo Sentalloy. In addition, breakdown potential of Neo Sentalloy Ionguard in Ora-Bliss (900 ppm) was much higher than that of Neo Sentalloy although both wires had similar corrosion potential in Ora-Bliss (450 and 900 ppm). The XPS results for Neo Sentalloy Ionguard suggested that the layers consisted of TiO(2) and TiN were present on the surface and the layers may improve the corrosion properties.

75 FR 60480 - In the Matter of Certain Bulk Welding Wire Containers and Components Thereof and Welding Wire...

Science.gov (United States)

2010-09-30

... Welding Wire Containers and Components Thereof and Welding Wire; Notice of Commission Determination To... within the United States after importation of certain bulk welding wire containers, components thereof, and welding wire by reason of infringement of certain claims of United States Patent Nos. 6,260,781; 6...

Monte Carlo simulation of efficient data acquisition for an entire-body PET scanner

Energy Technology Data Exchange (ETDEWEB)

Isnaini, Ismet; Obi, Takashi [Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8503 (Japan); Yoshida, Eiji, E-mail: rush@nirs.go.jp [National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Yamaya, Taiga [National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan)

2014-07-01

Conventional PET scanners can image the whole body using many bed positions. On the other hand, an entire-body PET scanner with an extended axial FOV, which can trace whole-body uptake images at the same time and improve sensitivity dynamically, has been desired. The entire-body PET scanner would have to process a large amount of data effectively. As a result, the entire-body PET scanner has high dead time at a multiplex detector grouping process. Also, the entire-body PET scanner has many oblique line-of-responses. In this work, we study an efficient data acquisition for the entire-body PET scanner using the Monte Carlo simulation. The simulated entire-body PET scanner based on depth-of-interaction detectors has a 2016-mm axial field-of-view (FOV) and an 80-cm ring diameter. Since the entire-body PET scanner has higher single data loss than a conventional PET scanner at grouping circuits, the NECR of the entire-body PET scanner decreases. But, single data loss is mitigated by separating the axially arranged detector into multiple parts. Our choice of 3 groups of axially-arranged detectors has shown to increase the peak NECR by 41%. An appropriate choice of maximum ring difference (MRD) will also maintain the same high performance of sensitivity and high peak NECR while at the same time reduces the data size. The extremely-oblique line of response for large axial FOV does not contribute much to the performance of the scanner. The total sensitivity with full MRD increased only 15% than that with about half MRD. The peak NECR was saturated at about half MRD. The entire-body PET scanner promises to provide a large axial FOV and to have sufficient performance values without using the full data.

Plasma chemistry in wire chambers

International Nuclear Information System (INIS)

Wise, J.

1990-05-01

The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an 55 Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed

Moths on the Flatbed Scanner: The Art of Joseph Scheer

Directory of Open Access Journals (Sweden)

Stephen L. Buchmann

2011-12-01

Full Text Available During the past decade a few artists and even fewer entomologists discovered flatbed scanning technology, using extreme resolution graphical arts scanners for acquiring high magnification digital images of plants, animals and inanimate objects. They are not just for trip receipts anymore. The special attributes of certain scanners, to image thick objects is discussed along with the technical features of the scanners including magnification, color depth and shadow detail. The work of pioneering scanner artist, Joseph Scheer from New York’s Alfred University is highlighted. Representative flatbed-scanned images of moths are illustrated along with techniques to produce them. Collecting and preparing moths, and other objects, for scanning are described. Highlights of the Fulbright sabbatical year of professor Scheer in Arizona and Sonora, Mexico are presented, along with comments on moths in science, folklore, art and pop culture. The use of flatbed scanners is offered as a relatively new method for visualizing small objects while acquiring large files for creating archival inkjet prints for display and sale.

Scanner-based macroscopic color variation estimation

Science.gov (United States)

Kuo, Chunghui; Lai, Di; Zeise, Eric

2006-01-01

Flatbed scanners have been adopted successfully in the measurement of microscopic image artifacts, such as granularity and mottle, in print samples because of their capability of providing full color, high resolution images. Accurate macroscopic color measurement relies on the use of colorimeters or spectrophotometers to provide a surrogate for human vision. The very different color response characteristics of flatbed scanners from any standard colorimetric response limits the utility of a flatbed scanner as a macroscopic color measuring device. This metamerism constraint can be significantly relaxed if our objective is mainly to quantify the color variations within a printed page or between pages where a small bias in measured colors can be tolerated as long as the color distributions relative to the individual mean values is similar. Two scenarios when converting color from the device RGB color space to a standardized color space such as CIELab are studied in this paper, blind and semi-blind color transformation, depending on the availability of the black channel information. We will show that both approaches offer satisfactory results in quantifying macroscopic color variation across pages while the semi-blind color transformation further provides fairly accurate color prediction capability.

Prediction of Bond Wire Fatigue of IGBTs in a PV Inverter Under a Long-Term Operation

DEFF Research Database (Denmark)

Reigosa, Paula Diaz; Wang, Huai; Yang, Yongheng

2016-01-01

consumption of bond wires of IGBT modules in a Photovoltaic (PV) inverter. The variations in IGBT parameters (e.g., on-state collector-emitter voltage), lifetime models, and environmental and operational stresses are taken into account in the lifetime prediction. The distribution of the annual lifetime...... consumption is estimated based on a long-term annual stress profile of solar irradiance and ambient temperature. The proposed method enables a more realistic lifetime prediction with a specified confidence level compared to the state-of-the-art approaches. A study case of IGBT modules in a 10 kW three......Bond wire fatigue is one of the dominant failure mechanisms in IGBT modules under cyclic stresses. However, there are still major challenges ahead to achieve a realistic bond wire lifetime prediction in field operation. This paper proposes a Monte Carlo based analysis method to predict the lifetime...

A scanner for single photon emission tomography

International Nuclear Information System (INIS)

Smith, D.B.; Cumpstey, D.E.; Evans, N.T.S.; Coleman, J.D.; Ettinger, K.V.; Mallard, J.R.

1982-01-01

The technique of single photon ECT has now been available for some eighteen years, but has yet still to be exploited fully. The difficulties of doing this lie in the need for gathering data of sufficiently good statistical accuracy in a reasonable counting time, in the uniformity of detector sensitivity, and in the means for correcting the image satisfactorily for photon attenuation within the body. The relative ease with which a general purpose gamma camera can be adapted to give rotation around the patient makes this an attractive practical approach to the problem. However, the sensitivity of gamma cameras over their field of view is by no means uniform, and their sensitivity is less good than that of purpose-designed scanners when no more than about ten sections through the body are required. There is therefore a need to assess the clinical usefulness of a whole body tomographic scanner of high sensitivity and uniformity. Such a machine is the Aberdeen Section Scanner Mark II described

Modeling and simulation of the fluid flow in wire electrochemical machining with rotating tool (wire ECM)

Science.gov (United States)

Klocke, F.; Herrig, T.; Zeis, M.; Klink, A.

2017-10-01

Combining the working principle of electrochemical machining (ECM) with a universal rotating tool, like a wire, could manage lots of challenges of the classical ECM sinking process. Such a wire-ECM process could be able to machine flexible and efficient 2.5-dimensional geometries like fir tree slots in turbine discs. Nowadays, established manufacturing technologies for slotting turbine discs are broaching and wire electrical discharge machining (wire EDM). Nevertheless, high requirements on surface integrity of turbine parts need cost intensive process development and - in case of wire-EDM - trim cuts to reduce the heat affected rim zone. Due to the process specific advantages, ECM is an attractive alternative manufacturing technology and is getting more and more relevant for sinking applications within the last few years. But ECM is also opposed with high costs for process development and complex electrolyte flow devices. In the past, few studies dealt with the development of a wire ECM process to meet these challenges. However, previous concepts of wire ECM were only suitable for micro machining applications. Due to insufficient flushing concepts the application of the process for machining macro geometries failed. Therefore, this paper presents the modeling and simulation of a new flushing approach for process assessment. The suitability of a rotating structured wire electrode in combination with an axial flushing for electrodes with high aspect ratios is investigated and discussed.

Geometric calibration between PET scanner and structured light scanner

DEFF Research Database (Denmark)

Kjer, Hans Martin; Olesen, Oline Vinter; Paulsen, Rasmus Reinhold

2011-01-01

Head movements degrade the image quality of high resolution Positron Emission Tomography (PET) brain studies through blurring and artifacts. Manny image reconstruction methods allows for motion correction if the head position is tracked continuously during the study. Our method for motion tracking...... is a structured light scanner placed just above the patient tunnel on the High Resolution Research Tomograph (HRRT, Siemens). It continuously registers point clouds of a part of the patient's face. The relative motion is estimated as the rigid transformation between frames. A geometric calibration between...

Empolder and application of LiveWire program

International Nuclear Information System (INIS)

Zhang Bo; Li Jing; Wang Xiaoming

2007-01-01

LiveWire is a specific module of Netscape Web server to actualize CGI function; through LiveWire application program one can create dynamic web page on web site. This article introduces how to write LiveWire application code, have to compile, debug and manage LiveWire application programs, and how to apply LiveWire application program on Netscape Web server to create a dynamic web page. (authors)

Method for calibration of an axial tomographic scanner

International Nuclear Information System (INIS)

Sparks, R.A.

1977-01-01

The method of calibrating an axial tomographic scanner including frame means having an opening therein in which an object to be examined is to be placed, source and detector means mounted on the frame means for directing one or more beams of penetrating radiation through the object from the source to the detector means, and means to rotate the scanner including the source and detector means about the object whereby a plurality of sets of data corresponding to the transmission or absorption by the object of a plurality of beams of penetrating radiation are collected; the calibration method comprising mounting calibration means supporting an adjustable centering member onto the frame means, positioning the adjustable centering member at approximately the center of rotation of the scanner, placing position-sensitive indicator means adjacent the approximately centered member, rotating the scanner and the calibration means mounted thereon at least one time and, if necessary, adjusting the positioning of the centering member until the centering member is coincident with the center of rotation of the scanner as determined by minimum deflection of the position-sensitive indicator means, rotating and translating the source and detector means and determining for each angular orientation of the frame means supporting the source and detector means the central position of each translational scan relative to the centered member and/or if a plurality of detectors are utilized with the detector means for each planar slice of the object being examined, the central position of each translational scan for each detector relative to the centered member

Control of flow past a circular cylinder via a spanwise surface wire: effect of the wire scale

Energy Technology Data Exchange (ETDEWEB)

Ekmekci, Alis [University of Toronto Institute for Aerospace Studies, Toronto, ON (Canada); Rockwell, Donald [Lehigh University, Department of Mechanical Engineering, Bethlehem, PA (United States)

2011-09-15

Flow phenomena induced by a single spanwise wire on the surface of a circular cylinder are investigated via a cinema technique of particle image velocimetry (PIV). The primary aim of this investigation is to assess the effect of the wire scale. To this end, consideration is given to wires with different diameters that are 0.5, 1.2, and 2.9% of the cylinder diameter. The Reynolds number has a subcritical value of 10,000. Compared to the thickness of the unperturbed boundary layer developing around the cylinder between 5 and 75 from the forward stagnation point, the former two wires have smaller scales and the latter has a larger scale. Two angular locations of the wire, defined with respect to the forward stagnation point of the cylinder, are found to be critical. When the wire is located at these critical angles, either the most significant extension or the contraction of the time-mean separation bubble occurs in the near wake. These critical angles depend on the wire scale: the smaller the wire, the larger the critical angle. The small-scale and large-scale wires that have diameters of 1.2 and 2.9% of the cylinder diameter induce bistable shear-layer oscillations between different separation modes when placed at their respective critical angles corresponding to maximum extension of the near-wake bubble. These oscillations have irregular time intervals that are much longer than the time scale associated with the classical Karman instability. Moreover, the large-scale wire can either significantly attenuate or intensify the Karman mode of vortex shedding at the critical states; in contrast, the small-scale wires do not notably alter the strength of the Karman instability. (orig.)

Determination of transverse phase-space and momentum error from size measurements along the 50-MeV H/sup -/ RCS injection line

International Nuclear Information System (INIS)

Cho, Y.; Crosbie, E.A.; Takeda, H.

1981-01-01

The 50-Mev H/sup -/ injection line for the RCS at Argonne National Laboratory has 16 quadrupole and eight bending magnets. Horizontal and vertical profiles can be obtained at 12 wire scanner positions. Size information from these profiles can be used to determine the three ellipses parameters in each plane required to describe the transverse phase space. Those locations that have dispersion permit the momentum error to be used as a fourth fitting parameter. The assumed accuracy of the size measurements provides an error matrix that predicts the rms errors of the fitted parameters. 3 refs

Preliminary Single-Phase Mixing Test using Wire Mesh System in a wire-wrapped 37-rod Bundle

International Nuclear Information System (INIS)

Bae, Hwang; Kim, Hyungmo; Lee, Dong Won; Choi, Hae Seob; Choi, Sun Rock; Chang, Seokkyu; Kim, Seok; Euh, Dongjin; Lee, Hyeongyeon

2014-01-01

In this paper, preliminary tests of the wire-mesh sensor are introduced before measuring of mixing coefficient in the wire-wrapped 37-pin fuel assembly for a sodium-cooled fast reactor. Through this preliminary test, it was confirmed that city water can be used as a tracer for demineralized water as a base. A simple test was performed to evaluate the characteristics of a wire mesh with of a short pipe shape. The conductivity of de-mineralized water and city water is linearly increased for the limited temperature ranges as the temperature is increased. The reliability of the wire mesh sensor was estimated based on the averages and standard deviations of the plane image using the cross points. A wire mesh sensor is suitable to apply to a single-phase flow measurement for a mixture with de-mineralized water and city water. A wire mesh sensor and system have been traditionally used to measure the void fraction of a two-phase flow field with gas and liquid. Recently, Ylonen et al. successfully designed and commissioned a measurement system for a single-phase flow using a wire mesh sensor

A potential environment for lasing below 15 nm initiated by exploding wire in water

Czech Academy of Sciences Publication Activity Database

Koláček, Karel; Prukner, Václav; Schmidt, Jiří; Frolov, Oleksandr; Štraus, Jaroslav

2010-01-01

Roč. 28, č. 1 (2010), s. 61-67 ISSN 0263-0346. [International Conference on the Frontiers of Plasma Physics and Technology/4th./. Kathmandu, Nepal, 06.04.2009-10.04.2009] R&D Projects: GA MŠk LA08024; GA MŠk(CZ) LC528; GA AV ČR KAN300100702; GA AV ČR KJB100430702 Institutional research plan: CEZ:AV0Z20430508 Keywords : exploding wire in water * modeling of wire explosion * measurement of H-alpha line profile Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.656, year: 2010 http://journals.cambridge.org/action/displayFulltext?type=1&fid=7482804&jid=LPB&volumeId=28&issueId=01&aid=7482796

Performance of an improved first generation optical CT scanner for 3D dosimetry

International Nuclear Information System (INIS)

Qian, Xin; Wuu, Cheng-Shie; Adamovics, John

2013-01-01

Performance analysis of a modified 3D dosimetry optical scanner based on the first generation optical CT scanner OCTOPUS is presented. The system consists of PRESAGE™ dosimeters, the modified 3D scanner, and a new developed in-house user control panel written in Labview program which provides more flexibility to optimize mechanical control and data acquisition technique. The total scanning time has been significantly reduced from initial 8 h to ∼2 h by using the modified scanner. The functional performance of the modified scanner has been evaluated in terms of the mechanical integrity uncertainty of the data acquisition process. Optical density distribution comparison between the modified scanner, OCTOPUS and the treatment plan system has been studied. It has been demonstrated that the agreement between the modified scanner and treatment plans is comparable with that between the OCTOPUS and treatment plans. (note)

TH-CD-207B-05: Measurement of CT Bow-Tie Profiles Using a Linear Array Detector

Energy Technology Data Exchange (ETDEWEB)

Yang, K; Li, X; Liu, B [Massachusetts General Hospital, Boston, MA (United States)

2016-06-15

Purpose: To accurately measure CT bow-tie profiles from various manufacturers and to provide non-proprietary information for CT system modeling. Methods: A GOS-based linear detector (0.8 mm per pixel and 51.2 cm in length) with a fast data sampling speed (0.24 ms/sample) was used to measure the relative profiles of bow-tie filters from a collection of eight CT scanners by three different vendors, GE (LS Xtra, LS VCT, Discovery HD750), Siemens (Sensation 64, Edge, Flash, Force), and Philips (iBrilliance 256). The linear detector was first calibrated for its energy response within typical CT beam quality ranges and compared with an ion chamber and analytical modeling (SPECTRA and TASMIP). A geometrical calibration process was developed to determine key parameters including the distance from the focal spot to the linear detector, the angular increment of the gantry at each data sampling, the location of the central x-ray on the linear detector, and the angular response of the detector pixel. Measurements were performed under axial-scan modes for most representative bow-tie filters and kV selections from each scanner. Bow-tie profiles were determined by re-binning the measured rotational data with an angular accuracy of 0.1 degree using the calibrated geometrical parameters. Results: The linear detector demonstrated an energy response as a solid state detector, which is close to the CT imaging detector. The geometrical calibration was proven to be sufficiently accurate (< 1mm in error for distances >550 mm) and the bow-tie profiles measured from rotational mode matched closely to those from the gantry-stationary mode. Accurate profiles were determined for a total of 21 bow-tie filters and 83 filter/kV combinations from the abovementioned scanner models. Conclusion: A new improved approach of CT bow-tie measurement was proposed and accurate bow-tie profiles were provided for a broad list of CT scanner models.

Accuracy of automated volumetry of pulmonary nodules across different multislice CT scanners

International Nuclear Information System (INIS)

Das, Marco; Muehlenbruch, Georg; Mahnken, Andreas H.; Katoh, Markus; Guenther, Rolf W.; Wildberger, Joachim E.; Ley-Zaporozhan, Julia; Kauczor, Hans-Ulrich; Gietema, H.A.; Prokop, Mathias; Czech, Andre; Diederich, Stefan; Bakai, Annemarie; Salganicoff, Marcos

2007-01-01

The purpose of this study was to compare the accuracy of an automated volumetry software for phantom pulmonary nodules across various 16-slice multislice spiral CT (MSCT) scanners from different vendors. A lung phantom containing five different nodule categories (intraparenchymal, around a vessel, vessel attached, pleural, and attached to the pleura), with each category comprised of 7-9 nodules (total, n = 40) of varying sizes (diameter 3-10 mm; volume 6.62 mm 3 -525 mm 3 ), was scanned with four different 16-slice MSCT scanners (Siemens, GE, Philips, Toshiba). Routine and low-dose chest protocols with thin and thick collimations were applied. The data from all scanners were used for further analysis using a dedicated prototype volumetry software. Absolute percentage volume errors (APE) were calculated and compared. The mean APE for all nodules was 8.4% (±7.7%) for data acquired with the 16-slice Siemens scanner, 14.3% (±11.1%) for the GE scanner, 9.7% (±9.6%) for the Philips scanner and 7.5% (±7.2%) for the Toshiba scanner, respectively. The lowest APEs were found within the diameter size range of 5-10 mm and volumes >66 mm 3 . Nodule volumetry is accurate with a reasonable volume error in data from different scanner vendors. This may have an important impact for intraindividual follow-up studies. (orig.)

Hot wire chemical vapor deposition: limits and opportunities of protecting the tungsten catalyzer from silicide with a cavity

International Nuclear Information System (INIS)

Frigeri, P.A.; Nos, O.; Bengoechea, S.; Frevert, C.; Asensi, J.M.; Bertomeu, J.

2009-01-01

Hot Wire Chemical Vapor Deposition (HW-CVD) is one of the most promising techniques for depositing the intrinsic microcrystalline silicon layer for the production of micro-morph solar cells. However, the silicide formation at the colder ends of the tungsten wire drastically reduces the lifetime of the catalyzer, thus limiting its industrial exploitation. A simple but interesting strategy to decrease the silicide formation is to hide the electrical contacts of the catalyzer in a long narrow cavity which reduces the probability of the silane molecules to reach the colder ends of the wire. In this paper, the working mechanism of the cavity is elucidated. Measurements of the thickness profile of the silicon deposited in the internal walls of the cavity have been compared with those predicted using a simple diffusion model based on the assumption of Knudsen flow. A lifetime study of the protected and unprotected wires has been carried out. The different mechanisms which determine the deterioration of the catalyzer have been identified and discussed.

47 CFR 32.2321 - Customer premises wiring.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Customer premises wiring. 32.2321 Section 32... Customer premises wiring. (a) This account shall include all amounts transferred from the former Account 232, Station Connections, inside wiring subclass. (b) Embedded Customer Premises Wiring is that...

Magnetic domain propagation in Pt/Co/Pt micro wires with engineered coercivity gradients along and across the wire

Energy Technology Data Exchange (ETDEWEB)

Jarosz, A., E-mail: arctgh@ifmpan.poznan.pl [Institute of Molecular Physics, Polish Academy of Sciences, ul. M. Smoluchowskiego 17, 60-179 Poznań (Poland); Gaul, A. [Department of Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel (Germany); Urbaniak, M. [Institute of Molecular Physics, Polish Academy of Sciences, ul. M. Smoluchowskiego 17, 60-179 Poznań (Poland); Ehresmann, A. [Department of Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel (Germany); Stobiecki, F. [Institute of Molecular Physics, Polish Academy of Sciences, ul. M. Smoluchowskiego 17, 60-179 Poznań (Poland)

2017-08-01

Highlights: • Electron lithography and ion bombardment were used to modify the Co/Pt micro-wires. • Two-dimensional perpendicular magnetic anisotropy gradient was engineered. • Engineered anisotropy gradient allowed to control domain wall positions in the wires. • Simulations confirm the influence of defects on a remanent state of the wires. - Abstract: Pt(15 nm)/[Co(0.6 nm)/Pt(1.5 nm)]{sub 4} multilayers with perpendicular magnetic anisotropy were patterned into several-micrometer wide wires by electron-beam lithography. Bombarding the wires with He{sup +} ions with a fluence gradient along the wire results in a spatial gradient of switching fields that allows a controllable positioning of domain walls. The influence of the reduced anisotropy near the wire edges causes a remanent state in which the reversal close to the long edges precedes that in the middle of the wires. Experiments using Kerr microscopy prove this effect and micromagnetic simulations corroborate that a decrease of the anisotropy at the edges is responsible for the effect.

Sensitive and simple method for measuring wire tensions

International Nuclear Information System (INIS)

Atac, M.; Mishina, M.

1982-08-01

Measuring tension of wires in drift chambers and multiwire proportional chambers after construction is an important process because sometimes wires get loose after soldering, crimping or glueing. One needs to sort out wires which have tensions below a required minimum value to prevent electrostatic instabilities. There have been several methods reported on this subject in which the wires were excited either with sinusoidal current under magnetic field or with sinusoidal voltage electrostatically coupled to the wire, searching for a resonating frequency with which the wires vibrate mechanically. Then the vibration is detected either visually, optically or with magnetic pick-up directly touching the wires. Any of these is only applicable to the usual multiwire chamber which has open access to the wire plane. They also need fairly large excitation currents to induce a detectable vibration to the wires. Here we report a very simple method that can be used for any type of wire chamber or proportional tube system for measuring wire tension. Only a very small current is required for the wire excitation to obtain a large enough signal because it detects the induced emf voltage across a wire. A sine-wave oscillator and a digital voltmeter are sufficient devices aside from a permanent magnet to provide the magnetic field around the wire. A useful application of this method to a large system is suggested

Efficient system modeling for a small animal PET scanner with tapered DOI detectors

International Nuclear Information System (INIS)

Zhang, Mengxi; Zhou, Jian; Yang, Yongfeng; Qi, Jinyi; Rodríguez-Villafuerte, Mercedes

2016-01-01

A prototype small animal positron emission tomography (PET) scanner for mouse brain imaging has been developed at UC Davis. The new scanner uses tapered detector arrays with depth of interaction (DOI) measurement. In this paper, we present an efficient system model for the tapered PET scanner using matrix factorization and a virtual scanner geometry. The factored system matrix mainly consists of two components: a sinogram blurring matrix and a geometrical matrix. The geometric matrix is based on a virtual scanner geometry. The sinogram blurring matrix is estimated by matrix factorization. We investigate the performance of different virtual scanner geometries. Both simulation study and real data experiments are performed in the fully 3D mode to study the image quality under different system models. The results indicate that the proposed matrix factorization can maintain image quality while substantially reduce the image reconstruction time and system matrix storage cost. The proposed method can be also applied to other PET scanners with DOI measurement. (paper)

Characterization of a Large, Low-Cost 3D Scanner

Directory of Open Access Journals (Sweden)

Jeremy Straub

2015-01-01

Full Text Available Imagery-based 3D scanning can be performed by scanners with multiple form factors, ranging from small and inexpensive scanners requiring manual movement around a stationary object to large freestanding (nearly instantaneous units. Small mobile units are problematic for use in scanning living creatures, which may be unwilling or unable to (or for the very young and animals, unaware of the need to hold a fixed position for an extended period of time. Alternately, very high cost scanners that can capture a complete scan within a few seconds are available, but they are cost prohibitive for some applications. This paper seeks to assess the performance of a large, low-cost 3D scanner, presented in prior work, which is able to concurrently capture imagery from all around an object. It provides the capabilities of the large, freestanding units at a price point akin to the smaller, mobile ones. This allows access to 3D scanning technology (particularly for applications requiring instantaneous imaging at a lower cost. Problematically, prior analysis of the scanner’s performance was extremely limited. This paper characterizes the efficacy of the scanner for scanning both inanimate objects and humans. Given the importance of lighting to visible light scanning systems, the scanner’s performance under multiple lighting configurations is evaluated, characterizing its sensitivity to lighting design.

A near-infrared confocal scanner

International Nuclear Information System (INIS)

Lee, Seungwoo; Yoo, Hongki

2014-01-01

In the semiconductor industry, manufacturing of three-dimensional (3D) packages or 3D integrated circuits is a high-performance technique that requires combining several functions in a small volume. Through-silicon vias, which are vertical electrical connections extending through a wafer, can be used to direct signals between stacked chips, thus increasing areal density by stacking and connecting multiple patterned chips. While defect detection is essential in the semiconductor manufacturing process, it is difficult to identify defects within a wafer or to monitor the bonding results between bonded surfaces because silicon and many other semiconductor materials are opaque to visible wavelengths. In this context, near-infrared (NIR) imaging is a promising non-destructive method to detect defects within silicon chips, to inspect bonding between chips and to monitor the chip alignment since NIR transmits through silicon. In addition, a confocal scanner provides high-contrast, optically-sectioned images of the specimen due to its ability to reject out-of-focus noise. In this study, we report an NIR confocal scanner that rapidly acquires high-resolution images with a large field of view through silicon. Two orthogonal line-scanning images can be acquired without rotating the system or the specimen by utilizing two orthogonally configured resonant scanning mirrors. This NIR confocal scanner can be efficiently used as an in-line inspection system when manufacturing semiconductor devices by rapidly detecting defects on and beneath the surface. (paper)

Mountain Plains Learning Experience Guide: Electrical Wiring. Course: Electrical Wiring Rough-In.

Science.gov (United States)

Arneson, R.; And Others

One of two individualized courses included in an electrical wiring curriculum, this course covers electrical installations that are generally hidden within the structure. The course is comprised of four units: (1) Outlet and Switch Boxes, (2) Wiring, (3) Service Entrance, and (4) Signal and Low Voltage Systems. Each unit begins with a Unit…

49 CFR 393.28 - Wiring systems.

Science.gov (United States)

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Wiring systems. 393.28 Section 393.28 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.28 Wiring systems...

Experimental validation of a method characterizing bow tie filters in CT scanners using a real-time dose probe

International Nuclear Information System (INIS)

McKenney, Sarah E.; Nosratieh, Anita; Gelskey, Dale; Yang Kai; Huang Shinying; Chen Lin; Boone, John M.

2011-01-01

Purpose: Beam-shaping or ''bow tie'' (BT) filters are used to spatially modulate the x-ray beam in a CT scanner, but the conventional method of step-and-shoot measurement to characterize a beam's profile is tedious and time-consuming. The theory for characterization of bow tie relative attenuation (COBRA) method, which relies on a real-time dosimeter to address the issues of conventional measurement techniques, was previously demonstrated using computer simulations. In this study, the feasibility of the COBRA theory is further validated experimentally through the employment of a prototype real-time radiation meter and a known BT filter. Methods: The COBRA method consisted of four basic steps: (1) The probe was placed at the edge of a scanner's field of view; (2) a real-time signal train was collected as the scanner's gantry rotated with the x-ray beam on; (3) the signal train, without a BT filter, was modeled using peak values measured in the signal train of step 2; and (4) the relative attenuation of the BT filter was estimated from filtered and unfiltered data sets. The prototype probe was first verified to have an isotropic and linear response to incident x-rays. The COBRA method was then tested on a dedicated breast CT scanner with a custom-designed BT filter and compared to the conventional step-and-shoot characterization of the BT filter. Using basis decomposition of dual energy signal data, the thickness of the filter was estimated and compared to the BT filter's manufacturing specifications. The COBRA method was also demonstrated with a clinical whole body CT scanner using the body BT filter. The relative attenuation was calculated at four discrete x-ray tube potentials and used to estimate the thickness of the BT filter. Results: The prototype probe was found to have a linear and isotropic response to x-rays. The relative attenuation produced from the COBRA method fell within the error of the relative attenuation measured with the step-and-shoot method

Electromagnetic Behaviour of Metallic Wire Structures

CERN Document Server

Chui, S T

2013-01-01

Despite the recent development and interest in the photonics of metallic wire structures, the relatively simple concepts and physics often remain obscured or poorly explained to those who do not specialize in the field. Electromagnetic Behaviour of Metallic Wire Structures provides a clear and coherent guide to understanding these phenomena without excessive numerical calculations.   Including both background material and detailed derivations of the various different formulae applied, Electromagnetic Behaviour of Metallic Wire Structures describes how to extend basic circuit theory relating to voltages, currents, and resistances of metallic wire networks to include situations where the currents are no longer spatially uniform along the wire. This lays a foundation for a deeper understanding of the many new phenomena observed in meta-electromagnetic materials.   Examples of applications are included to support this new approach making Electromagnetic Behaviour of Metallic Wire Structures a comprehensive and ...

SPECIFIC FEATURES OF TECHNOLOGY OF MANUFACTURING A ZINC-COATED TUB WIRE FOR MUZZLE (BOTTLE’ HOOD WIRE

Directory of Open Access Journals (Sweden)

D. B. Zuev

2016-01-01

Full Text Available The paper presents the main technical specifications of galvanized low carbon wire for muzzles (bottle’hood wire, consistent with the exploitation requirements to the wire in the manufacture and use of muzzles. The main criteria when selecting the steel grade and upon selection of the technological processes are given. 

The performance characteristics of the Philips Gemini PET/CT scanner

International Nuclear Information System (INIS)

O'Keefe, G.J.; Papenfuss, A.T.; Scott, A.M.; Rowe, C.C.

2002-01-01

Full text: The Department of Nuclear Medicine, Centre for PET at the ARMC is commissioning a next generation PET/CT scanner based on gadolinium silicic dioxide (GSO) crystal technology to replace the BGO crystal PET scanner that has been in operation since 1992. The Gemini PET/CT scanner is a fully 3D PET system which offers significantly increased resolution and sensitivity allowing wholebody scans in under 30 minutes. Until the late 90's, PET scanners were largely used with septa for neurological imaging and the performance characteristics of PET scanners were presented according to the NEMA-NU2-94 standard which specifically addresses the performance of PET scanners for neurological applications. PET is now largely used without septa for oncological imaging and as such, the NEMA-NU2-94 standard does not adequately reflect performance. The NEMA-NU2-2001 standard was designed to incorporate the effects of out-of-FOV activity and its contribution to performance by virtue of the increased scatter and randoms that result when performing wholebody scans without the use of septa. As part of the acceptance program of the Allegro/Gemini systems, the NEMA-NU2-2001 standard will be used to characterise the spatial resolution, sensitivity, randoms and scatter contributions and the Noise Equivalent Count rate (NECr). These results will be presented and compared with the ECAT 951/31R performance characteristics. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

Pacemaker wires

International Nuclear Information System (INIS)

Fransson, S.G.

1993-01-01

Evaluation of pacemaker wires were performed by comparing Advanced Multiple Beam Equalization Radiography (AMBER) with conventional chest radiography. The scanning equalization technique of the AMBER unit makes it superior to conventional technique in the depiction of different structures in the mediastinum or in the pleural sinuses. So far motion artifacts have not been considered clinically important. The longer exposure time, however, may impair the assessment of pacemaker wires. The motion artifact described may not only make adequate evaluation impossible but may even give a false impression of a lead fracture. The difference between the two systems was significant. (orig.)

Addressing Spatial Variability of Surface-Layer Wind with Long-Range WindScanners

DEFF Research Database (Denmark)

Berg, Jacob; Vasiljevic, Nikola; Kelly, Mark C.

2015-01-01

of the WindScanner data is high, although the fidelity of the estimated vertical velocity component is significantly limited by the elevation angles of the scanner heads. The system of long-range WindScanners presented in this paper is close to being fully operational, with the pilot study herein serving...

NOAA-9 Earth Radiation Budget Experiment (ERBE) scanner offsets determination

Science.gov (United States)

Avis, Lee M.; Paden, Jack; Lee, Robert B., III; Pandey, Dhirendra K.; Stassi, Joseph C.; Wilson, Robert S.; Tolson, Carol J.; Bolden, William C.

1994-01-01

The Earth Radiation Budget Experiment (ERBE) instruments are designed to measure the components of the radiative exchange between the Sun, Earth and space. ERBE is comprised of three spacecraft, each carrying a nearly identical set of radiometers: a three-channel narrow-field-of-view scanner, a two-channel wide-field-of-view (limb-to-limb) non-scanning radiometer, a two-channel medium field-of view (1000 km) non-scanning radiometer, and a solar monitor. Ground testing showed the scanners to be susceptible to self-generated and externally generated electromagnetic noise. This paper describes the pre-launch corrective measures taken and the post-launch corrections to the NOAA-9 scanner data. The NOAA-9 scanner has met the mission objectives in accuracy and precision, in part because of the pre-launch reductions of and post-launch data corrections for the electromagnetic noise.

Improved quality of image got through whole-body CT scanner

International Nuclear Information System (INIS)

Asahina, Kiyotaka

1980-01-01

The quality of brain images taken with a whole-body CT scanner has so far been generally inferior in quality to those got through a CT scanner exclusively used for brains. In order to improve the whole-body CT scanner so as to get better brain image, its detection system has been made multichannel; the capacity of its X-ray tube, increased; and its software, innovated. As a result, the spatial resolution has been improved from 5.51 p/cm to 9.01 p/cm, the contrast resolution has been improved from 3.2 mm% to 1.5 mm%, with the noise maintained at 0.5%. In clinical examination, the image quality has been improved equally well for brains, abdomens and lungs. Especially high appreciation is given to the diagnosis information got through this new scanner. (author)

Inhomogeneous wire explosion in water

International Nuclear Information System (INIS)

Hwangbo, C.K.; Kong, H.J.; Lee, S.S.

1980-01-01

Inhomogeneous processes are observed in underwater copper wire explosion induced by a condensed capacitor discharge. The wire used is 0.1 mm in diameter and 10 mm long, and the capacitor of 2 μF is charged to 5 KV. A N 2 laser is used for the diagnostic of spatial extension of exploding copper vapour. The photographs obtained in this experiment show unambiguously the inhomogeneous explosion along the exploding wire. The quenching of plasma by the surrounding water inhibits the expansion of the vapour. It is believed the observed inhomogeneous explosion along the wire is located and localized around Goronkin's striae, which was first reported by Goronkin and discussed by Froengel as a pre-breakdown phenomenon. (author)

HTS Wire Development Workshop: Proceedings

Energy Technology Data Exchange (ETDEWEB)

1994-07-01

The 1994 High-Temperature Superconducting Wire Development Workshop was held on February 16--17 at the St. Petersburg Hilton and Towers in St. Petersburg, Florida. The meeting was hosted by Florida Power Corporation and sponsored by the US Department of Energy`s Superconductivity Program for Electric Power Systems. The meeting focused on recent high-temperature superconducting wire development activities in the Department of Energy`s Superconductivity Systems program. The meeting opened with a general discussion on the needs and benefits of superconductivity from a utility perspective, the US global competitiveness position, and an outlook on the overall prospects of wire development. The meeting then focused on four important technology areas: Wire characterization: issues and needs; technology for overcoming barriers: weak links and flux pinning; manufacturing issues for long wire lengths; and physical properties of HTS coils. Following in-depth presentations, working groups were formed in each technology area to discuss the most important current research and development issues. The working groups identified research areas that have the potential for greatly enhancing the wire development effort. These areas are discussed in the summary reports from each of the working groups. This document is a compilation of the workshop proceedings including all general session presentations and summary reports from the working groups.

Si Wire-Array Solar Cells

Science.gov (United States)

Boettcher, Shannon

2010-03-01

Micron-scale Si wire arrays are three-dimensional photovoltaic absorbers that enable orthogonalization of light absorption and carrier collection and hence allow for the utilization of relatively impure Si in efficient solar cell designs. The wire arrays are grown by a vapor-liquid-solid-catalyzed process on a crystalline (111) Si wafer lithographically patterned with an array of metal catalyst particles. Following growth, such arrays can be embedded in polymethyldisiloxane (PDMS) and then peeled from the template growth substrate. The result is an unusual photovoltaic material: a flexible, bendable, wafer-thickness crystalline Si absorber. In this paper I will describe: 1. the growth of high-quality Si wires with controllable doping and the evaluation of their photovoltaic energy-conversion performance using a test electrolyte that forms a rectifying conformal semiconductor-liquid contact 2. the observation of enhanced absorption in wire arrays exceeding the conventional light trapping limits for planar Si cells of equivalent material thickness and 3. single-wire and large-area solid-state Si wire-array solar cell results obtained to date with directions for future cell designs based on optical and device physics. In collaboration with Michael Kelzenberg, Morgan Putnam, Joshua Spurgeon, Daniel Turner-Evans, Emily Warren, Nathan Lewis, and Harry Atwater, California Institute of Technology.

Mechanical behavior of M-Wire and conventional NiTi wire used to manufacture rotary endodontic instruments.

Science.gov (United States)

Pereira, Erika S J; Gomes, Renata O; Leroy, Agnès M F; Singh, Rupinderpal; Peters, Ove A; Bahia, Maria G A; Buono, Vicente T L

2013-12-01

Comparison of physical and mechanical properties of one conventional and a new NiTi wire, which had received an additional thermomechanical treatment. Specimens of both conventional (NiTi) and the new type of wire, called M-Wire (MW), were subjected to tensile and three-point bending tests, Vickers microhardness measurements, and to rotating-bending fatigue tests at a strain-controlled level of 6%. Fracture surfaces were observed by scanning electron microscopy and the non-deformed microstructures by transmission electron microscopy. The thermomechanical treatment applied to produce the M-Wire apparently increased the tensile strength and Vickers microhardness of the material, but its apparent Young modulus was smaller than that of conventionally treated NiTi. The three-point bending tests showed a higher flexibility for MW which also exhibited a significantly higher number of cycles to failure. M-Wire presented mechanical properties that can render endodontic instruments more flexible and fatigue resistant than those made with conventionally processed NiTi wires. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Comparison of Analysis, Simulation, and Measurement of Wire-to-Wire Crosstalk. Part 2

Science.gov (United States)

Bradley, Arthur T.; Yavoich, Brian James; Hodson, Shane M.; Godley, Franklin

2010-01-01

In this investigation, we compare crosstalk analysis, simulation, and measurement results for electrically short configurations. Methods include hand calculations, PSPICE simulations, Microstripes transient field solver, and empirical measurement. In total, four representative physical configurations are examined, including a single wire over a ground plane, a twisted pair over a ground plane, generator plus receptor wires inside a cylindrical conduit, and a single receptor wire inside a cylindrical conduit. Part 1 addresses the first two cases, and Part 2 addresses the final two. Agreement between the analysis methods and test data is shown to be very good.

Comparison of Analysis, Simulation, and Measurement of Wire-to-Wire Crosstalk. Part 1

Science.gov (United States)

Bradley, Arthur T.; Yavoich, Brian James; Hodson, Shame M.; Godley, Richard Franklin

2010-01-01

In this investigation, we compare crosstalk analysis, simulation, and measurement results for electrically short configurations. Methods include hand calculations, PSPICE simulations, Microstripes transient field solver, and empirical measurement. In total, four representative physical configurations are examined, including a single wire over a ground plane, a twisted pair over a ground plane, generator plus receptor wires inside a cylindrical conduit, and a single receptor wire inside a cylindrical conduit. Part 1 addresses the first two cases, and Part 2 addresses the final two. Agreement between the analysis, simulation, and test data is shown to be very good.

Getting "Wired" for McLuhan's Cyberculture.

Science.gov (United States)

McMurdo, George

1995-01-01

Examines the introduction of the computing magazine, "Wired", into the United Kingdom's (UK) market. Presents conversations with the founder and editorial staff of the UK edition, and discusses the accessibility of "Wired" via the World Wide Web. Describes 10 articles from United States "Wired" back-issues and…

Ignition and spread of electrical wire fires

OpenAIRE

Huang, Xinyan

2012-01-01

Ignition of electrical wires by external heating is investigated in order to gain a better understanding of the initiation of electrical-wire fires. An ignition-to- spread model is developed to systematically explain ignition and the following transition to spread. The model predicts that for a higher-conductance wire it is more difficult to achieve ignition and the weak flame may extinguish during the transition phase because of a large conductive heat loss along the wire core. Wires with tw...

Phosphorus in antique iron music wire.

Science.gov (United States)

Goodway, M

1987-05-22

Harpsichords and other wire-strung musical instruments were made with longer strings about the beginning of the 17th century. This change required stronger music wire. Although these changes coincided with the introduction of the first mass-produced steel (iron alloyed with carbon), carbon was not found in samples of antique iron harpsichord wire. The wire contained an amount of phosphorus sufficient to have impeded its conversion to steel, and may have been drawn from iron rejected for this purpose. The method used to select pig iron for wire drawing ensured the highest possible phosphorus content at a time when its presence in iron was unsuspected. Phosphorus as an alloying element has had the reputation for making steel brittle when worked cold. Nevertheless, in replicating the antique wire, it was found that lowcarbon iron that contained 0.16 percent phosphorus was easily drawn to appropriate gauges and strengths for restringing antique harpsichords.

Electro-mechanics of drift tube wires

International Nuclear Information System (INIS)

Milburn, R.H.

1997-01-01

The position and stability of the sense wires in very long drift tubes are affected by both gravitational and electrostatic forces, as well as by the wire tension. For a tube to be used as an element of a high-resolution detector all these forces and their effects must be understood in appropriately precise detail. In addition, the quality control procedures applied during manufacture and detector installation must be adequate to ensure that the internal wire positions remain within tolerances. It may be instructive to practitioners to review the simple theory of a taut wire in the presence of anisotropic gravitational and electrostatic fields to illustrate the conditions for stability, the equilibrium wire displacement from straightness, and the effect of the fields on the mechanical vibration frequencies. These last may be used to monitor the wire configuration externally. A number of practical formulae result and these are applied to illustrative examples. (orig.)

The CT scanner as a therapy machine

International Nuclear Information System (INIS)

Iwamoto, K.S.; Norman, A.

1990-01-01

Many tumors in the brain and in other tissues can be delineated precisely in images obtained with a CT scanner. After the scan is obtained the patient is taken to another room for radiation therapy and is positioned in the beam with the aid of external markers, simulators or stereotactic devices. This procedure is time consuming and subject to error when precise localization of the beam is desired. The CT scanner itself, with the addition of the collimator, is capable of delivering radiation therapy with great precision without the need for external markers. The patient can be scanned and treated on the same table, the isocenter of the beam can be placed precisely in the center of the lesion, the beam can be restricted to just those planes in which the lesion appears, several arcs can be obtained by simply tilting the gantry, and the position of the patient in the beam can be monitored continuously during therapy. The authors describe the properties of the CTX, the CT scanner modified for therapy. (author). 6 refs.; 6 figs

Computer-aided analysis of digital dental impressions obtained from intraoral and extraoral scanners.

Science.gov (United States)

Bohner, Lauren Oliveira Lima; De Luca Canto, Graziela; Marció, Bruno Silva; Laganá, Dalva Cruz; Sesma, Newton; Tortamano Neto, Pedro

2017-11-01

The internal and marginal adaptation of a computer-aided design and computer-aided manufacturing (CAD-CAM) prosthesis relies on the quality of the 3-dimensional image. The quality of imaging systems requires evaluation. The purpose of this in vitro study was to evaluate and compare the trueness of intraoral and extraoral scanners in scanning prepared teeth. Ten acrylic resin teeth to be used as a reference dataset were prepared according to standard guidelines and scanned with an industrial computed tomography system. Data were acquired with 4 scanner devices (n=10): the Trios intraoral scanner (TIS), the D250 extraoral scanner (DES), the Cerec Bluecam intraoral scanner (CBIS), and the Cerec InEosX5 extraoral scanner (CIES). For intraoral scanners, each tooth was digitized individually. Extraoral scanning was obtained from dental casts of each prepared tooth. The discrepancy between each scan and its respective reference model was obtained by deviation analysis (μm) and volume/area difference (μm). Statistical analysis was performed using linear models for repeated measurement factors test and 1-way ANOVA (α=.05). No significant differences in deviation values were found among scanners. For CBIS and CIES, the deviation was significantly higher (PDentistry. Published by Elsevier Inc. All rights reserved.

Initial results of the quality control in 11 computed tomography scanners at Curitiba

International Nuclear Information System (INIS)

Kodlulovich, S; Oliveira, L.; Jakubiak, R.R.; Miquelin, C.A.

2008-01-01

The aim of this study was to evaluate the image quality of 11 scanners installed in public and private centers of Curitiba, Brazil. This sample represents 30% of the CT scanners in the city so far. The ACR CT accreditation phantom was used to verify the accomplishment of the scanners performance to the international quality requirements. The results indicate that efforts should be concentrated in the maintenance of the equipments and specific training of the technicians. Most of the scanners have showed some non-conformity. In 27,5% of the sample the positioning requirement wasn't accomplished. The CT number accuracy evaluation showed that in 72,3 % of the scanners the CT numbers were out of the tolerance range, reaching values 35% greater than the limit. The low contrast resolution criteria weren't accomplished in 9% of the scanners. The main concern is that there isn't a specific program to evaluate the image quality of the CT scanners neither to estimate the CT doses in the procedures. (author)

Commercial and Industrial Wiring.

Science.gov (United States)

Kaltwasser, Stan; Flowers, Gary

This module is the third in a series of three wiring publications, includes additional technical knowledge and applications required for job entry in the commercial and industrial wiring trade. The module contains 15 instructional units that cover the following topics: blueprint reading and load calculations; tools and equipment; service;…

Study on the fluid dynamics of nitrogen and hydrogen gases subjected to wires element in monolithic channel

Directory of Open Access Journals (Sweden)

Rashidi Amirah

2017-01-01

Full Text Available Ammonia has a very significant value in the fertilizer industry where it was being synthesized via Haber-Bosch process in the early 19th century. As the process utilize high operating conditions, it imposes high capital cost and is an energy-consuming process. Due to this unsustainable process, researchers have initiated an alternative to overcome this drawback by performing a simulation in microfluidic environment using ambient temperature and pressure (25°C and 1 atm. Wires element configured in a 50 mm x 10 mm, (L x D dimension monolithic channel with different spacing and number of wires, arranged axially in 60o pitch have been introduced to investigate the dynamic mixing of nitrogen and hydrogen for ammonia synthesis. As the wires are configured in a different manner, the results show dissimilar volume fraction profile, contours and mixing index. Creating suitable obstruction with larger obstruction space enhanced the mixing. Reducing spacing from 2 mm to 1.5 mm illustrates fluctuating velocity at the centre of the channel causing the flow velocity become less than the set velocity 0.05ms-1. By substituting from 19 wires to 13 wires to the flow, chaotic advection occurs lead to the increased of mixing index up to 94%.

Wire alignment system for ATF LINAC

International Nuclear Information System (INIS)

Hayano, H.; Takeda, S.; Matsumoto, H.; Matsui, T.

1994-01-01

A wire based alignment system is adopted to make less than 40μm precision alignment for injector linac of Accelerator Test Facility (ATF). The system consists of two stretched SUS wires, pickup coils and active mover stages. The position of pickup coils in a mount which will be installed into LINAC stages is set to the calculated wire position prior to installation. All of LINAC stages are then moved to keep the calculated position by the active mover. The test results of wire position detection in a long term are described. (author)

Nickel contaminated titanium weld wire study

International Nuclear Information System (INIS)

Coffin, G.R.; Sumstine, R.L.

1979-01-01

Attachment of thermocouples to fuel rod welding problems at Exxon Nuclear Company and INEL prompted an investigation study of the titanium filler wire material. It was found that the titanium filler wire was contaminated with nickel which was jacketed on the wire prior to the drawing process at the manufacturers. A method was developed to 100% inspect all filler wire for future welding application. This method not only indicates the presence of nickel contamination but indicates quantity of contamination. The process is capable of high speed inspection necessary for various high speed manufacturing processes

Californium Recovery from Palladium Wire

Energy Technology Data Exchange (ETDEWEB)

Burns, Jon D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-08-01

The recovery of ²⁵²Cf from palladium-²⁵²Cf cermet wires was investigated to determine the feasibility of implementing it into the cermet wire production operation at Oak Ridge National Laboratory’s Radiochemical Engineering Development Center. The dissolution of Pd wire in 8 M HNO₃ and trace amounts of HCl was studied at both ambient and elevated temperatures. These studies showed that it took days to dissolve the wire at ambient temperature and only 2 hours at 60°C. Adjusting the ratio of the volume of solvent to the mass of the wire segment showed little change in the kinetics of dissolution, which ranged from 0.176 mL/mg down to 0.019 mL/mg. A successful chromatographic separation of ¹⁵³Gd, a surrogate for ²⁵²Cf, from Pd was demonstrated using AG 50x8 cation exchange resin with a bed volume of 0.5 mL and an internal diameter of 0.8 cm.

Design Optimization of a TOF, Breast PET Scanner

OpenAIRE

Lee, Eunsin; Werner, Matthew E.; Karp, Joel S.; Surti, Suleman

2013-01-01

A dedicated breast positron emission tomography (PET) scanner with limited angle geometry can provide flexibility in detector placement around the patient as well as the ability to combine it with other imaging modalities. A primary challenge of a stationary limited angle scanner is the reduced image quality due to artifacts present in the reconstructed image leading to a loss in quantitative information. Previously it has been shown that using time-of-flight (TOF) information in image recons...

Wire number dependence of the implosion dynamics, stagnation, and radiation output of tungsten wire arrays at Z driver

Energy Technology Data Exchange (ETDEWEB)

Mazarakis, Michael G.; Stygar, William A.; Sinars, Daniel B.; Cuneo, Michael E.; Nash, Thomas J.; Chandler, Gordon A.; Keith Matzen, M.; Porter, John L.; Struve, Kenneth W.; McDaniel, Dillon H. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States); Deeney, Christopher E. [National Nuclear Security Administration, Washington, D.C. 20585 (United States); Douglas, Melissa R. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Chittenden, Jerry [Imperial College, London, SW and 2BW (United Kingdom)

2011-11-15

We report results of the experimental campaign, which studied the initiation, implosion dynamics, and radiation yield of tungsten wire arrays as a function of the wire number. The wire array dimensions and mass were those of interest for the Z-pinch driven Inertial Confinement Fusion (ICF) program. An optimization study of the x-ray emitted peak power, rise time, and full width at half maximum was effectuated by varying the wire number while keeping the total array mass constant and equal to {approx}5.8 mg. The driver utilized was the {approx}20-MA Z accelerator before refurbishment in its usual short pulse mode of 100 ns. We studied single arrays of 20-mm diameter and 1-cm height. The smaller wire number studied was 30 and the largest 600. It appears that 600 is the highest achievable wire number with present day's technology. Radial and axial diagnostics were utilized including crystal monochromatic x-ray backlighter. An optimum wire number of {approx}375 was observed which was very close to the routinely utilized 300 for the ICF program in Sandia.

Wire number dependence of the implosion dynamics, stagnation, and radiation output of tungsten wire arrays at Z driver

International Nuclear Information System (INIS)

Mazarakis, Michael G.; Stygar, William A.; Sinars, Daniel B.; Cuneo, Michael E.; Nash, Thomas J.; Chandler, Gordon A.; Keith Matzen, M.; Porter, John L.; Struve, Kenneth W.; McDaniel, Dillon H.; Deeney, Christopher E.; Douglas, Melissa R.; Chittenden, Jerry

2011-01-01

We report results of the experimental campaign, which studied the initiation, implosion dynamics, and radiation yield of tungsten wire arrays as a function of the wire number. The wire array dimensions and mass were those of interest for the Z-pinch driven Inertial Confinement Fusion (ICF) program. An optimization study of the x-ray emitted peak power, rise time, and full width at half maximum was effectuated by varying the wire number while keeping the total array mass constant and equal to ∼5.8 mg. The driver utilized was the ∼20-MA Z accelerator before refurbishment in its usual short pulse mode of 100 ns. We studied single arrays of 20-mm diameter and 1-cm height. The smaller wire number studied was 30 and the largest 600. It appears that 600 is the highest achievable wire number with present day's technology. Radial and axial diagnostics were utilized including crystal monochromatic x-ray backlighter. An optimum wire number of ∼375 was observed which was very close to the routinely utilized 300 for the ICF program in Sandia.

Performance studies of the vibration wire monitor on the test stand with low energy electron beam

International Nuclear Information System (INIS)

Okabe, Kota; Yoshimoto, Masahiro; Kinsho, Michikazu

2015-01-01

In the high intensity proton accelerator as the Japan Proton Accelerator Research Complex (J-PARC) accelerators, serious radiation and residual dose is induced by a small beam loss such a beam halo. Therefore, diagnostics of the beam halo formation is one of the most important issues to control the beam loss. For the beam halo monitor, the vibration wire monitor (VWM) has a potential for investigating the beam halo and weak beam scanning. The VWM has a wide dynamic range, high resolution and the VWM is not susceptible to secondary electrons and electric noises. We have studied the VWM features as a new beam-halo monitor on the test stand with low energy electron gun. The frequency shift of the irradiated vibration wire was confirmed about wire material and the electron beam profile measured by using the VWM was consistent with the results of the Faraday cup measurement. Also we calculated a temperature distribution on the vibration wire which is irradiated by the electron beam with the numerical simulation. The simulations have been fairly successful in reproducing the transient of the irradiated vibration wire frequency measured by test stand experiments. In this paper, we will report a result of performance evaluation for the VWM on the test stands and discuss the VWM for beam halo diagnostic. (author)

High-performance, stretchable, wire-shaped supercapacitors.

Science.gov (United States)

Chen, Tao; Hao, Rui; Peng, Huisheng; Dai, Liming

2015-01-07

A general approach toward extremely stretchable and highly conductive electrodes was developed. The method involves wrapping a continuous carbon nanotube (CNT) thin film around pre-stretched elastic wires, from which high-performance, stretchable wire-shaped supercapacitors were fabricated. The supercapacitors were made by twisting two such CNT-wrapped elastic wires, pre-coated with poly(vinyl alcohol)/H3PO4 hydrogel, as the electrolyte and separator. The resultant wire-shaped supercapacitors exhibited an extremely high elasticity of up to 350% strain with a high device capacitance up to 30.7 F g(-1), which is two times that of the state-of-the-art stretchable supercapacitor under only 100% strain. The wire-shaped structure facilitated the integration of multiple supercapacitors into a single wire device to meet specific energy and power needs for various potential applications. These supercapacitors can be repeatedly stretched from 0 to 200% strain for hundreds of cycles with no change in performance, thus outperforming all the reported state-of-the-art stretchable electronics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A rural CT scanner: evaluating the effect on local health care

International Nuclear Information System (INIS)

Merkens, B.J.; Mowbray, R.D.; Creeden, L.; Engels, P.T.; Rothwell, D.M.; Chan, B.T.B.; Tu, K.

2006-01-01

The first small rural hospital in Ontario to propose a computed tomography (CT) scanner was in Walkerton, a town 160 km north of London. The Ontario Ministry of Health approved the proposal as a pilot project to evaluate the effect on local health care of a rural scanner. This evaluation study had 3 parts: a survey of physicians, a survey of patients, and an analysis of population CT scanning rates. The physicians in the area served by the scanner were asked about its impact on their care of their patients in a mailed questionnaire and in semistructured interviews. Scanner outpatients were given a questionnaire in which they rated the importance of its advantages. The analysis of scanning rates--the ratio of number of scans to estimated population--compared rates in the area with other Ontario rates before and after the scanner was introduced. The physicians reported that local CT allowed them to diagnose and treat patients sooner, closer to home, and with greater confidence. On average, 75% of the patients ranked faster and closer access as very important. Scanning rates in the area rose, although they did not match urban rates. The study confirms that the rural scanner changed the area's health care in significant ways and that it helped to narrow the gap between rural and urban service levels. We recommend that CT be expanded to other rural regions. (author)

Verification of a CT scanner using a miniature step gauge

DEFF Research Database (Denmark)

Cantatore, Angela; Andreasen, J.L.; Carmignato, S.

2011-01-01

The work deals with performance verification of a CT scanner using a 42mm miniature replica step gauge developed for optical scanner verification. Errors quantification and optimization of CT system set-up in terms of resolution and measurement accuracy are fundamental for use of CT scanning...

[Mechanics analysis of fracture of orthodontic wires].

Science.gov (United States)

Wang, Yeping; Sun, Xiaoye; Zhang, Longqi

2003-03-01

Fracture problem of orthodontic wires was discussed in this paper. The calculation formulae of bending stress and tensile stress were obtained. All main factors that affect bending stress and tensile stress of orthodontic wires were analyzed and discussed. It was concluded that the main causes of fracture of orthodontic wires were fatigue and static disruption. Some improving proposals for preventing fracture of orthodontic wires were put forward.

Lunar Module Wiring Design Considerations and Failure Modes

Science.gov (United States)

Interbartolo, Michael

2009-01-01

This slide presentation reviews the considerations for the design of wiring for the Lunar Module. Included are a review of the choice of conductors and insulations, the wire splicing (i.e., crimping, and soldering), the wire connectors, and the fabrication of the wire harnesses. The problems in fabrication include the wires being the wrong length, the damage due to the sharp edges, the requried use of temproary protective covers and inadequate training. The problems in the wire harness installation include damge from sharp eges, work on adjacent harnesses, connector damage, and breaking wires. Engineering suggestions from the Apollo-era in reference to the conductors that are reviewed include: the use of plated conductors, and the use of alloys for stronger wiring. In refernce to insulation, the suggestions from Apollo era include the use of polymer tape-wrap wire insulation due to the light weight, however, other types of modern insulation might be more cost-effective. In reference to wire splices and terminal boards the suggestions from the Apollo Era include the use of crimp splices as superior to solder splices, joining multiple wire to a common point using modular plug-ins might be more reliable, but are heavier than crimp splicing. For connectors, the lessons from the Apollo era indicate that a rear environmental seal that does not require additional potting is preferred, and pins should be crimped or welded to the incoming wires and be removable from the rear of the connector.

Quality assurance for MR stereotactic imaging for three Siemens scanners

International Nuclear Information System (INIS)

Kozubikova, P.; Novotny, J. Jr.; Kulhova, K.; Mihalova, P.; Tamasova, J.; Veselsk, T.

2014-01-01

Quality assurance of stereotactic imaging, especially with MRI (magnetic resonance imaging), is a complex issue. It can be divided in the basic verification and commissioning of a particular new scanner or a new scanning MRI protocol that is being implemented into a clinical practice and the routine quality assurance performed for each single radiosurgical case. The aim of this study was geometric distortion assessment in MRI with a special PTGR (Physikalisch-Technische Gesellschaft fuer Radiologie - GmbH, Tuebingen, Germany) target phantom. PTGR phantom consists of 21 three-dimensional cross-hairs filled with contrast medium. Cross hairs are positioned at known Leksell coordinates with a precision of better than 0.1 mm and covering the whole stereotactic space. The phantom can be fixed in the Leksell stereotactic frame and thus stereotactic imaging procedures can be reproduced following exactly the same steps as for a real patient, including also the stereotactic image definition in the Leksell GammaPlan. Since the geometric position (stereotactic coordinates) of each cross-hair is known based on the construction of the phantom, it can be compared with the actual measured Leksell coordinates based on the stereotactic MRI. Deviations between expected and actual coordinates provide information about the level of distortion. The measured distortions proved satisfactory accuracy precision for stereotactic localization at 1.5 T Siemens Magnetom Avanto scanner, Siemens Magnetom Symphony scanner and 3T Siemens Magnetom Skyra scanner (Na Homolce Hospital, Prague). The mean distortion for these MR scanners for standard imaging protocol (T1 weighted 3D images) were 0.8 mm, 1.1 mm and 1.1 mm and maximum distortions were 1.3 mm, 1.9 mm and 2.2 mm, respectively.There was detected dependence of the distortions on the slice orientation and the type of imaging protocol. Image distortions are also property of each particular scanner, the worst distortion were observed for 3T

Superconducting wire for the T-15 toroidal magnet

International Nuclear Information System (INIS)

Klimenko, E.Yu.; Kruglov, V.S.; Martovetskij, N.N.

1987-01-01

Main characteristics of a wire designed for the T-15 toroidal superconducting magnet production are given. The wire with circulation cooling is a twist of 11 niobium-tin wires 1.5 mm in diameter, joined electrolytically by two copper tubes with 3 mm inside diameter. The wire is capable to carry 10 kA current in the 8.5 T induction field. Wire features and structures promote to receive high structural current density in winding: diffuseness of superconducting-to-normal transition increases wire stability, screw symmetry od a current-carrying core provides wire resistance to pulse longitudinal field effect at plasma current disruption, low bronze thermal conductivity in a twist increases stability to outside pulse perturbations

Carbon wire chamber at sub-atmospheric pressure

Energy Technology Data Exchange (ETDEWEB)

Charles, G., E-mail: charlesg@ipno.in2p3.fr; Audouin, L., E-mail: audouin@ipno.in2p3.fr; Bettane, J.; Dupre, R.; Genolini, B.; Hammoudi, N.; Imre, M.; Le Ven, V.; Maroni, A.; Mathon, B.; Nguyen Trung, T.; Rauly, E.

2017-05-21

Present in many experiments, wire and drift chambers have been used in a large variety of shapes and configurations during the last decades. Nevertheless, their readout elements has not evolved much: tungsten, sometimes gold-plated or aluminum, wires. By taking advantage of the developments in the manufacture of conducting carbon fiber, we could obtain interesting improvements for wire detectors. In this article, we present recent tests and simulations using carbon fibers to readout signal in place of traditional tungsten wires. Unlike metallic wires, their low weight guaranties a reduced quantity of material in the active area.

Fast estimation of first-order scattering in a medical x-ray computed tomography scanner using a ray-tracing technique.

Science.gov (United States)

Liu, Xin

2014-01-01

This study describes a deterministic method for simulating the first-order scattering in a medical computed tomography scanner. The method was developed based on a physics model of x-ray photon interactions with matter and a ray tracing technique. The results from simulated scattering were compared to the ones from an actual scattering measurement. Two phantoms with homogeneous and heterogeneous material distributions were used in the scattering simulation and measurement. It was found that the simulated scatter profile was in agreement with the measurement result, with an average difference of 25% or less. Finally, tomographic images with artifacts caused by scatter were corrected based on the simulated scatter profiles. The image quality improved significantly.

The importance of carbon nanotube wire density, structural uniformity, and purity for fabricating homogeneous carbon nanotube-copper wire composites by copper electrodeposition

Science.gov (United States)

Sundaram, Rajyashree; Yamada, Takeo; Hata, Kenji; Sekiguchi, Atsuko

2018-04-01

We present the influence of density, structural regularity, and purity of carbon nanotube wires (CNTWs) used as Cu electrodeposition templates on fabricating homogeneous high-electrical performance CNT-Cu wires lighter than Cu. We show that low-density CNTWs (wires) with regular macro- and microstructures and high CNT content (>90 wt %) are essential for making homogeneous CNT-Cu wires. These homogeneous CNT-Cu wires show a continuous Cu matrix with evenly mixed nanotubes of high volume fractions (˜45 vol %) throughout the wire-length. Consequently, the composite wires show densities ˜5.1 g/cm3 (33% lower than Cu) and electrical conductivities ˜6.1 × 104 S/cm (>100 × CNTW conductivity). However, composite wires from templates with higher densities or structural inconsistencies are non-uniform with discontinuous Cu matrices and poor CNT/Cu mixing. These non-uniform CNT-Cu wires show conductivities 2-6 times lower than the homogeneous composite wires.

Repetitive display system of line profiles for Doppler broadening measurement

International Nuclear Information System (INIS)

Mohri, A.; Narihara, K.; Haba, K.

1982-10-01

Line profiles of impurities in visible and ultraviolet regions are repetitively displayed on a CRT with an interval of 250 mu s or 500 mu s, using a system composed of a Czerny-Turner monochromator with 1 m F.L., a self-resonant optical scanner, a photomultiplier shielded against hard X-rays and electronic circuits. The profile resolution is 0.035 nm FWHM. This system can be used in the environment of strong hard X-rays. (author)

Effect of environment on fatigue failure of controlled memory wire nickel-titanium rotary instruments.

Science.gov (United States)

Shen, Ya; Qian, Wei; Abtin, Houman; Gao, Yuan; Haapasalo, Markus

2012-03-01

This study examined the fatigue behavior of 2 types of nickel-titanium (NiTi) instruments made from a novel controlled memory NiTi wire (CM wire) under various environment conditions. Three conventional superelastic NiTi instruments of ProFile (Dentsply Maillefer, Ballaigues, Switzerland), Typhoon (Clinician's Choice Dental Products, New Milford, CT), and DS-SS0250425NEYY (Clinician's Choice Dental Products) and 2 new CM wire instruments of Typhoon CM and DS-SS0250425NEYY CM were subjected to rotational bending at the curvature of 35° in air, deionized water, 17% EDTA, or deionized water after immersion in 6% sodium hypochlorite for 25 minutes, and the number of revolutions of fracture (N(f)) was recorded. The fracture surface of all fragments was examined by a scanning electron microscope. The crack-initiation sites and the percentage of dimple area to the whole fracture cross-section were noted. Two new CM Wire instruments yielded an improvement of >4 to 9 times in N(f) than conventional NiTi files with the same design under various environments (P Wire instruments was significantly longer in liquid media than in air (P wire had one crack origin. The values of the area fraction occupied by the dimple region were significantly smaller on CM NiTi instruments than in conventional NiTi instruments under various environments (P < .05). Within the limitations of this study, the type of NiTi metal alloy (CM files vs conventional superelastic NiTi files) influences the cyclic fatigue resistance under various environments. The fatigue life of CM instruments is longer in liquid media than in air. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Influence of stress and phase on corrosion of a superelastic nickel-titanium orthodontic wire.

Science.gov (United States)

Segal, Nadav; Hell, Jess; Berzins, David W

2009-06-01

The purpose of this investigation was to study the effect of stress and phase transformation on the corrosion properties of a superelastic nickel-titanium orthodontic wire. The phase transformation profiles of superelastic nickel-titanium (Sentalloy, GAC International, Bohemia, NY) and beta-titanium (TMA, Ormco, Orange, Calif) archwires were analyzed by using differential scanning calorimetry. The force/deflection behavior of the wires at 37 degrees C was measured in a 3-point bending test per modified American Dental Association specification no. 32. Electrochemical testing consisted of monitoring the open circuit potential (OCP) for 2 hours followed by polarization resistance and cyclic polarization tests on archwire segments engaged in a 5-bracket simulation apparatus with bend deflections of 0.75, 1.5, or 3 mm in artificial saliva at 37 degrees C. Nondeflected segments were also tested. Sentalloy was additionally examined for bending and corrosion at 5 degrees C, where it exists as martensite and is devoid of stress-induced phase transformation. OCP at 2 hours and corrosion current density (i(corr)) were analyzed by using ANOVA and Tukey tests (alpha = .05) (n = 10 per deflection). Significant differences (P Sentalloy wires at 5 degrees C, but not for Sentalloy at 37 degrees C. Significant differences (P Sentalloy (37 degrees C) peaked at 0.75 mm deflection before the wire's stress-induced phase transformation point and then decreased with further deflection and transformation. The i(corr) values for TMA and Sentalloy at 5 degrees C, both of which do not undergo phase transformation with deformation, continuously increased from 0 to 1.5 mm deflection before decreasing at the 3.0-mm deflection. Stress increased the corrosion rate in nickel-titanium and beta-titanium orthodontic wires. Alterations in stress/strain associated with phase transformation in superelastic nickel-titanium might alter the corrosion rate in ways different from wires not undergoing phase

Defense Commissaries: Issues Related to the Sale of Electronic Scanner Data

National Research Council Canada - National Science Library

1998-01-01

In response to your request that we review DeCA'S sale of scanner data and its implementation of category management, this report identifies DeCA'S total revenue from selling scanner data and compares license revenues...

Ultra-High-Resolution Computed Tomography of the Lung: Image Quality of a Prototype Scanner

Science.gov (United States)

Kakinuma, Ryutaro; Moriyama, Noriyuki; Muramatsu, Yukio; Gomi, Shiho; Suzuki, Masahiro; Nagasawa, Hirobumi; Kusumoto, Masahiko; Aso, Tomohiko; Muramatsu, Yoshihisa; Tsuchida, Takaaki; Tsuta, Koji; Maeshima, Akiko Miyagi; Tochigi, Naobumi; Watanabe, Shun-ichi; Sugihara, Naoki; Tsukagoshi, Shinsuke; Saito, Yasuo; Kazama, Masahiro; Ashizawa, Kazuto; Awai, Kazuo; Honda, Osamu; Ishikawa, Hiroyuki; Koizumi, Naoya; Komoto, Daisuke; Moriya, Hiroshi; Oda, Seitaro; Oshiro, Yasuji; Yanagawa, Masahiro; Tomiyama, Noriyuki; Asamura, Hisao

2015-01-01

Purpose The image noise and image quality of a prototype ultra-high-resolution computed tomography (U-HRCT) scanner was evaluated and compared with those of conventional high-resolution CT (C-HRCT) scanners. Materials and Methods This study was approved by the institutional review board. A U-HRCT scanner prototype with 0.25 mm x 4 rows and operating at 120 mAs was used. The C-HRCT images were obtained using a 0.5 mm x 16 or 0.5 mm x 64 detector-row CT scanner operating at 150 mAs. Images from both scanners were reconstructed at 0.1-mm intervals; the slice thickness was 0.25 mm for the U-HRCT scanner and 0.5 mm for the C-HRCT scanners. For both scanners, the display field of view was 80 mm. The image noise of each scanner was evaluated using a phantom. U-HRCT and C-HRCT images of 53 images selected from 37 lung nodules were then observed and graded using a 5-point score by 10 board-certified thoracic radiologists. The images were presented to the observers randomly and in a blinded manner. Results The image noise for U-HRCT (100.87 ± 0.51 Hounsfield units [HU]) was greater than that for C-HRCT (40.41 ± 0.52 HU; P < .0001). The image quality of U-HRCT was graded as superior to that of C-HRCT (P < .0001) for all of the following parameters that were examined: margins of subsolid and solid nodules, edges of solid components and pulmonary vessels in subsolid nodules, air bronchograms, pleural indentations, margins of pulmonary vessels, edges of bronchi, and interlobar fissures. Conclusion Despite a larger image noise, the prototype U-HRCT scanner had a significantly better image quality than the C-HRCT scanners. PMID:26352144

Ultra-High-Resolution Computed Tomography of the Lung: Image Quality of a Prototype Scanner.

Directory of Open Access Journals (Sweden)

Ryutaro Kakinuma

Full Text Available The image noise and image quality of a prototype ultra-high-resolution computed tomography (U-HRCT scanner was evaluated and compared with those of conventional high-resolution CT (C-HRCT scanners.This study was approved by the institutional review board. A U-HRCT scanner prototype with 0.25 mm x 4 rows and operating at 120 mAs was used. The C-HRCT images were obtained using a 0.5 mm x 16 or 0.5 mm x 64 detector-row CT scanner operating at 150 mAs. Images from both scanners were reconstructed at 0.1-mm intervals; the slice thickness was 0.25 mm for the U-HRCT scanner and 0.5 mm for the C-HRCT scanners. For both scanners, the display field of view was 80 mm. The image noise of each scanner was evaluated using a phantom. U-HRCT and C-HRCT images of 53 images selected from 37 lung nodules were then observed and graded using a 5-point score by 10 board-certified thoracic radiologists. The images were presented to the observers randomly and in a blinded manner.The image noise for U-HRCT (100.87 ± 0.51 Hounsfield units [HU] was greater than that for C-HRCT (40.41 ± 0.52 HU; P < .0001. The image quality of U-HRCT was graded as superior to that of C-HRCT (P < .0001 for all of the following parameters that were examined: margins of subsolid and solid nodules, edges of solid components and pulmonary vessels in subsolid nodules, air bronchograms, pleural indentations, margins of pulmonary vessels, edges of bronchi, and interlobar fissures.Despite a larger image noise, the prototype U-HRCT scanner had a significantly better image quality than the C-HRCT scanners.

Diagnostics for high-brightness beams

International Nuclear Information System (INIS)

Shafer, R.E.

1990-01-01

Special techniques are required for beam diagnostics on high-brightness particle beams. Examples of high-brightness beams include low-emittance proton linacs (either pulsed or CW), electron linacs suitable for free-electron-laser applications, and future linear colliders. Non-interceptive and minimally-interceptive techniques for measuring beam current, position, profile, and transverse and longitudinal emittance will be reviewed. Included will be stripline, wire scanner, laser neutralization, beam-beam scattering, interceptive microgratings, spontaneous emission, optical transition radiation, and other techniques. 24 refs

Evaluation of a LED-based flatbed document scanner for radiochromic film dosimetry in transmission mode.

Science.gov (United States)

Lárraga-Gutiérrez, José Manuel; García-Garduño, Olivia Amanda; Treviño-Palacios, Carlos; Herrera-González, José Alfredo

2018-03-01

Flatbed scanners are the most frequently used reading instrument for radiochromic film dosimetry because its low cost, high spatial resolution, among other advantages. These scanners use a fluorescent lamp and a CCD array as light source and detector, respectively. Recently, manufacturers of flatbed scanners replaced the fluorescent lamp by light emission diodes (LED) as a light source. The goal of this work is to evaluate the performance of a commercial flatbed scanner with LED based source light for radiochromic film dosimetry. Film read out consistency, response uniformity, film-scanner sensitivity, long term stability and total dose uncertainty was evaluated. In overall, the performance of the LED flatbed scanner is comparable to that of a cold cathode fluorescent lamp (CCFL). There are important spectral differences between LED and CCFL lamps that results in a higher sensitivity of the LED scanner in the green channel. Total dose uncertainty, film response reproducibility and long-term stability of LED scanner are slightly better than those of the CCFL. However, the LED based scanner has a strong non-uniform response, up to 9%, that must be adequately corrected for radiotherapy dosimetry QA. The differences in light emission spectra between LED and CCFL lamps and its potential impact on film-scanner sensitivity suggest that the design of a dedicated flat-bed scanner with LEDs may improve sensitivity and dose uncertainty in radiochromic film dosimetry. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

SU-E-T-135: Investigation of Commercial-Grade Flatbed Scanners and a Medical- Grade Scanner for Radiochromic EBT Film Dosimetry.

Science.gov (United States)

Syh, J; Patel, B; Syh, J; Wu, H; Rosen, L; Durci, M; Katz, S; Sibata, C

2012-06-01

To evaluate the characteristics of commercial-grade flatbed scanners and medical-grade scanners for radiochromic EBT film dosimetry. Performance aspects of a Vidar Dosimetry Pro Advantage (Red), Epson 750 Pro, Microtek ArtixScan 1800f, and Microtek ScanMaker 8700 scanner for EBT2 Gafchromic film were evaluated in the categories of repeatability, maximum distinguishable optical density (OD) differentiation, OD variance, and dose curve characteristics. OD step film by Stouffer Industries containing 31 steps ranging from 0.05 to 3.62 OD was used. EBT films were irradiated with dose ranging from 20 to 600 cGy in 6×6 cm 2 field sizes and analyzed 24 hours later using RIT113 and Tomotherapy Film Analyzer software. Scans were performed in transmissive mode, landscape orientation, 16-bit image. The mean and standard deviation Analog to Digital (A/D) scanner value was measured by selecting a 3×3 mm 2 uniform area in the central region of each OD step from a total of 20 scans performed over several weeks. Repeatability was determined from the variance of OD step 0.38. Maximum distinguishable OD was defined as the last OD step whose range of A/D values does not overlap with its neighboring step. Repeatability uncertainty ranged from 0.1% for Vidar to 4% for Epson. Average standard deviation of OD steps ranged from 0.21% for Vidar to 6.4% for ArtixScan 1800f. Maximum distinguishable optical density ranged from 3.38 for Vidar to 1.32 for ScanMaker 8700. A/D range of each OD step corresponds to a dose range. Dose ranges of OD steps varied from 1% for Vidar to 20% for ScanMaker 8700. The Vidar exhibited a dose curve that utilized a broader range of OD values than the other scanners. Vidar exhibited higher maximum distinguishable OD, smaller variance in repeatability, smaller A/D value deviation per OD step, and a shallower dose curve with respect to OD. © 2012 American Association of Physicists in Medicine.

Accuracy of complete-arch model using an intraoral video scanner: An in vitro study.

Science.gov (United States)

Jeong, Il-Do; Lee, Jae-Jun; Jeon, Jin-Hun; Kim, Ji-Hwan; Kim, Hae-Young; Kim, Woong-Chul

2016-06-01

Information on the accuracy of intraoral video scanners for long-span areas is limited. The purpose of this in vitro study was to evaluate and compare the trueness and precision of an intraoral video scanner, an intraoral still image scanner, and a blue-light scanner for the production of digital impressions. Reference scan data were obtained by scanning a complete-arch model. An identical model was scanned 8 times using an intraoral video scanner (CEREC Omnicam; Sirona) and an intraoral still image scanner (CEREC Bluecam; Sirona), and stone casts made from conventional impressions of the same model were scanned 8 times with a blue-light scanner as a control (Identica Blue; Medit). Accuracy consists of trueness (the extent to which the scan data differ from the reference scan) and precision (the similarity of the data from multiple scans). To evaluate precision, 8 scans were superimposed using 3-dimensional analysis software; the reference scan data were then superimposed to determine the trueness. Differences were analyzed using 1-way ANOVA and post hoc Tukey HSD tests (α=.05). Trueness in the video scanner group was not significantly different from that in the control group. However, the video scanner group showed significantly lower values than those of the still image scanner group for all variables (P<.05), except in tolerance range. The root mean square, standard deviations, and mean negative precision values for the video scanner group were significantly higher than those for the other groups (P<.05). Digital impressions obtained by the intraoral video scanner showed better accuracy for long-span areas than those captured by the still image scanner. However, the video scanner was less accurate than the laboratory scanner. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Pre-wired systems prove their worth.

Science.gov (United States)

2012-03-01

The 'new generation' of modular wiring systems from Apex Wiring Solutions have been specified for two of the world's foremost teaching hospitals - the Royal London and St Bartholomew's Hospital, as part of a pounds sterling 1 billion redevelopment project, to cut electrical installation times, reduce on-site waste, and provide a pre-wired, factory-tested, power and lighting system. HEJ reports.

Laser measuring scanners and their accuracy limits

Science.gov (United States)

Jablonski, Ryszard

1993-09-01

Scanning methods have gained the greater importance for some years now due to a short measuring time and wide range of application in flexible manufacturing processes. This paper is a summing up of the autho?s creative scientific work in the field of measuring scanners. The research conducted allowed to elaborate the optimal configurations of measuring systems based on the scanning method. An important part of the work was the analysis of a measuring scanner - as a transducer of an angle rotation into the linear displacement which resulted in obtaining its much higher accuracy and finally in working out a measuring scanner eliminating the use of an additional reference standard. The completion of the work is an attempt to determine an attainable accuracy limit of scanning measurement of both length and angle. Using a high stability deflector and a corrected scanning lens one can obtain the angle determination over 30 (or 2 mm) to an accuracy 0 (or 0 tm) when the measuring rate is 1000 Hz or the range d60 (4 mm) with accuracy 0 " (0 jim) and measurement frequency 6 Hz.

Quantitative Assay for Starch by Colorimetry Using a Desktop Scanner

Science.gov (United States)

Matthews, Kurt R.; Landmark, James D.; Stickle, Douglas F.

2004-01-01

The procedure to produce standard curve for starch concentration measurement by image analysis using a color scanner and computer for data acquisition and color analysis is described. Color analysis is performed by a Visual Basic program that measures red, green, and blue (RGB) color intensities for pixels within the scanner image.

Characterization of the Li beam probe with a beam profile monitor on JET.

Science.gov (United States)

Nedzelskiy, I S; Korotkov, A; Brix, M; Morgan, P; Vince, J

2010-10-01

The lithium beam probe (LBP) is widely used for measurements of the electron density in the edge plasma of magnetically confined fusion experiments. The quality of LBP data strongly depends on the stability and profile shape of the beam. The main beam parameters are as follows: beam energy, beam intensity, beam profile, beam divergence, and the neutralization efficiency. For improved monitoring of the beam parameters, a beam profile monitor (BPM) from the National Electrostatics Corporation (NEC) has been installed in the Li beam line at JET. In the NEC BPM, a single grounded wire formed into a 45° segment of a helix is rotated by a motor about the axis of the helix. During each full revolution, the wire sweeps twice across the beam to give X and Y profiles. In this paper, we will describe the properties of the JET Li beam as measured with the BPM and demonstrate that it facilitates rapid optimization of the gun performance.

Dose profile study in head CT scans using radiochromic films

International Nuclear Information System (INIS)

Ladino G, A. M.; Prata M, A.

2016-10-01

Diagnostic images of computed tomography generate higher doses than other methods of diagnostic radiology using X-ray beam attenuation. Clinical applications of CT have been increased by technological advances, what leads to a wide variety of scanner in the Brazilian technological pool. It has been difficult to implement dose reduction strategies because of the lack of proper guidance on computed tomography examinations. However, CT scanners allow adjusting acquisition parameter according to the patients physical profile and diagnostic application for which the scan is intended. The knowledge of the dose distribution is important because changes in image acquisition parameters may provide dose reduction. In this study, it was used a cylindrical head phantom in PMMA with 5 openings, what allows dose measurement in 5 regions. In a GE CT scanner, Discovery model of 64 channels, the central slice of the head phantom was irradiated and the absorbed doses were measured using a pencil ionization chamber. Radiochromic film strips were placed in the peripheral and in the central region of the head phantom and was performed a scan of 10 cm in the phantom central region. The scan was performed using the head scanning protocol of the radiobiology service, with a voltage of 120 kV. After scanning, the radiochromic film strips were digitalized and their digital images were used to have the dose longitudinal profiles. The dose values recorded have variation in a range of 18.66 to 23.57 mGy. In the results it was compared the dose index values obtained by the pencil chamber measurement to the dose longitudinal profiles recorded by the film strips. (Author)

Dose profile study in head CT scans using radiochromic films

Energy Technology Data Exchange (ETDEWEB)

Ladino G, A. M.; Prata M, A., E-mail: amlgphys@gmail.com [Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil)

2016-10-15

Diagnostic images of computed tomography generate higher doses than other methods of diagnostic radiology using X-ray beam attenuation. Clinical applications of CT have been increased by technological advances, what leads to a wide variety of scanner in the Brazilian technological pool. It has been difficult to implement dose reduction strategies because of the lack of proper guidance on computed tomography examinations. However, CT scanners allow adjusting acquisition parameter according to the patients physical profile and diagnostic application for which the scan is intended. The knowledge of the dose distribution is important because changes in image acquisition parameters may provide dose reduction. In this study, it was used a cylindrical head phantom in PMMA with 5 openings, what allows dose measurement in 5 regions. In a GE CT scanner, Discovery model of 64 channels, the central slice of the head phantom was irradiated and the absorbed doses were measured using a pencil ionization chamber. Radiochromic film strips were placed in the peripheral and in the central region of the head phantom and was performed a scan of 10 cm in the phantom central region. The scan was performed using the head scanning protocol of the radiobiology service, with a voltage of 120 kV. After scanning, the radiochromic film strips were digitalized and their digital images were used to have the dose longitudinal profiles. The dose values recorded have variation in a range of 18.66 to 23.57 mGy. In the results it was compared the dose index values obtained by the pencil chamber measurement to the dose longitudinal profiles recorded by the film strips. (Author)

Ghost signals in Allison emittance scanners

International Nuclear Information System (INIS)

Stockli, Martin P.; Leitner, M.; Moehs, D.P.; Keller, R.; Welton, R.F.

2004-01-01

For over 20 years, Allison scanners have been used to measure emittances of low-energy ion beams. We show that scanning large trajectory angles produces ghost signals caused by the sampled beamlet impacting on an electric deflection plate. The ghost signal strength is proportional to the amount of beam entering the scanner. Depending on the ions, and their velocity, the ghost signals can have the opposite or the same polarity as the main beam signals. The ghost signals cause significant errors in the emittance estimates because they appear at large trajectory angles. These ghost signals often go undetected because they partly overlap with the real signals, are mostly below the 1% level, and often hide in the noise. A simple deflection plate modification is shown to reduce the ghost signal strength by over 99%

Ghost Signals In Allison Emittance Scanners

International Nuclear Information System (INIS)

Stockli, Martin P.; Leitner, M.; Keller, R.; Moehs, D.P.; Welton, R. F.

2005-01-01

For over 20 years, Allison scanners have been used to measure emittances of low-energy ion beams. We show that scanning large trajectory angles produces ghost signals caused by the sampled beamlet impacting on an electric deflection plate. The ghost signal strength is proportional to the amount of beam entering the scanner. Depending on the ions, and their velocity, the ghost signals can have the opposite or the same polarity as the main beam signals. The ghost signals cause significant errors in the emittance estimates because they appear at large trajectory angles. These ghost signals often go undetected because they partly overlap with the real signals, are mostly below the 1% level, and often hide in the noise. A simple deflection plate modification is shown to reduce the ghost signal strength by over 99%

Modern wiring practice

CERN Document Server

Steward, W E

2012-01-01

Continuously in print since 1952, Modern Wiring Practice has now been fully revised to provide an up-to-date source of reference to building services design and installation in the 21st century. This compact and practical guide addresses wiring systems design and electrical installation together in one volume, creating a comprehensive overview of the whole process for contractors and architects, as well as electricians and other installation engineers. Best practice is incorporated throughout, combining theory and practice with clear and accessible explanation, all

Domain observations of Fe and Co based amorphous wires

International Nuclear Information System (INIS)

Takajo, M.; Yamasaki, J.

1993-01-01

Domain observations were made on Fe and Co based amorphous magnetic wires that exhibit a large Barkhausen discontinuity during flux reversal. Domain patterns observed on the wire surface were compared with those found on a polished section through the center of the wire. It was confirmed that the Fe based wire consists of a shell and core region as previously proposed, however, there is a third region between them. This fairly thick transition region made up of domains at an angle of about 45 degree to the wire axis clearly lacking the closure domains of the previous model. The Co based wire does not have a clear core and shell domain structure. The center of the wire had a classic domain structure expected of uniaxial anisotropy with the easy axis normal to the wire axis. When a model for the residual stress quenched-in during cooling of large Fe bars is applied to the wire, the expected anisotropy is consistent with the domain patterns in the Fe based wire, however, shape anisotropy still plays a dominant role in defining the wire core in the Co based wire

Automatic reel controls filler wire in welding machines

Science.gov (United States)

Millett, A. V.

1966-01-01

Automatic reel on automatic welding equipment takes up slack in the reel-fed filler wire when welding operation is terminated. The reel maintains constant, adjustable tension on the wire during the welding operation and rewinds the wire from the wire feed unit when the welding is completed.

Method of preparing composite superconducting wire

International Nuclear Information System (INIS)

Verhoeven, J. D.; Finnemore, D. K.; Gibson, E. D.; Ostenson, J. E.; Schmidt, F. A.

1985-01-01

An improved method of preparing composite multifilament superconducting wire of Nb 3 Sn in a copper matrix which eliminates the necessity of coating the drawn wire with tin. A generalized cylindrical billet of an alloy of copper containing at least 15 weight percent niobium, present in the copper as discrete, randomly distributed and oriented dendritic-shaped particles, is provided with at least one longitudinal opening which is filled with tin to form a composite drawing rod. The drawing rod is then drawn to form a ductile composite multifilament wire containing a filament of tin. The ductile wire containing the tin can then be wound into magnet coils or other devices before heating to diffuse the tin through the wire to react with the niobium forming Nb 3 Sn. Also described is an improved method for making large billets of the copper-niobium alloy by consumable-arc casting

Structural characterisation and mechanical FE analysis of conventional and M-Wire Ni-Ti alloys used in endodontic rotary instruments.

Science.gov (United States)

Montalvão, Diogo; Alçada, Francisca Sena; Braz Fernandes, Francisco Manuel; de Vilaverde-Correia, Sancho

2014-01-01

The purpose of this study is to understand how the M-Wire alloy conditions the mechanical flexibility of endodontic rotary files at body temperature.Two different rotary instruments, a Profile GT 20/.06 and a Profile GT Series X 20/.06, were selected due to their geometrical similarity and their different constituent alloy. GT series X files are made from M-Wire, a Ni-Ti alloy allegedly having higher flexibility at body temperature. Both files were analysed by X-Ray Diffraction and Differential Scanning Calorimetry to investigate phase transformations and the effects of working temperature on these different alloys. Mechanical behaviour was assessed by means of static bending and torsional Finite Element simulations, taking into account the nonlinear superelastic behaviour of Ni-Ti materials. It was found that GT files present austenitic phase at body temperature, whereas GT series X present R-phase at temperatures under 40 °C with a potential for larger flexibility. For the same load conditions, simulations showed that the slight geometrical differences between the two files do not introduce great disagreement in the instruments' mechanical response. It was confirmed that M-Wire increases the instrument's flexibility, mainly due to the presence of R-phase at body temperature.

Comparison of working efficiency of terrestrial laser scanner in day and night conditions

Science.gov (United States)

Arslan, A. E.; Kalkan, K.

2013-10-01

Terrestrial Laser Scanning is a popular and widely used technique to scan existing objects, document historical sites and items, and remodel them if and when needed. Their ability to collect thousands of point data per second makes them an invaluable tool in many areas from engineering to historical reconstruction. There are many scanners in the market with different technical specifications. One main technical specification of laser scanners is range and illumination. In this study, it is tested to be determined the optimal working times of a laser scanner and the scanners consistency with its specifications sheet. In order to conduct this work, series of GNSS measurements in Istanbul Technical University have been carried out, connected to the national reference network, to determine precise positions of target points and the scanner, which makes possible to define a precise distance between the scanner and targets. Those ground surveys has been used for calibration and registration purposes. Two different scan campaigns conducted at 12 am and 11 pm to compare working efficiency of laser scanner in different illumination conditions and targets are measured with a handheld spectro-radiometer in order to determine their reflective characteristics. The obtained results are compared and their accuracies have been analysed.

FormScanner: Open-Source Solution for Grading Multiple-Choice Exams

Science.gov (United States)

Young, Chadwick; Lo, Glenn; Young, Kaisa; Borsetta, Alberto

2016-01-01

The multiple-choice exam remains a staple for many introductory physics courses. In the past, people have graded these by hand or even flaming needles. Today, one usually grades the exams with a form scanner that utilizes optical mark recognition (OMR). Several companies provide these scanners and particular forms, such as the eponymous…

Measurement of transverse emittance at the source of spin-polarized electrons at the S-DALINAC

Energy Technology Data Exchange (ETDEWEB)

Eckardt, Christian; Barday, Roman; Bonnes, Uwe; Eichhorn, Ralf; Enders, Joachim; Hessler, Christoph; Patalakha, Oleksandr; Platz, Markus; Poltoratska, Yuliya; Rick, Wolfgang [Institut fuer Kernphysik, TU Darmstadt (Germany); Ackermann, Wolfgang; Mueller, Wolfgang F.O.; Steiner, Bastian; Weiland, Thomas [Institut fuer Theorie Elektromagnetischer Felder, TU Darmstadt (Germany)

2008-07-01

A new injector concept for 100 keV spin-polarized electrons (SPIN) at the S-DALINAC has been developed. The transverse emittance was measured for beam characterization. The emittance is a quantity concerning the quality of the beam, describing the phase space area. Determination of the emittance requires measurement of the beam profile and knowledge of the focal length of a beam focussing device. A wire scanner unit consisting of two 50 {mu}m diameter tungsten wires is used for the beam-profile measurement. Data analysis is performed by fitting a gaussian model distribution to estimate the 1{sigma} beam radius. Each determined beam width is correlated to the corresponding focal length of a magnetic lens, and a parabola fit is applied to calculate the parameters of the {sigma}-matrix. The square root of the determinant of the {sigma}-matrix defines the emittance. The results of the calculation are presented and the emittance is compared to theoretical estimates.

The accuracy of the CAD system using intraoral and extraoral scanners for designing of fixed dental prostheses.

Science.gov (United States)

Shimizu, Sakura; Shinya, Akikazu; Kuroda, Soichi; Gomi, Harunori

2017-07-26

The accuracy of prostheses affects clinical success and is, in turn, affected by the accuracy of the scanner and CAD programs. Thus, their accuracy is important. The first aim of this study was to evaluate the accuracy of an intraoral scanner with active triangulation (Cerec Omnicam), an intraoral scanner with a confocal laser (3Shape Trios), and an extraoral scanner with active triangulation (D810). The second aim of this study was to compare the accuracy of the digital crowns designed with two different scanner/CAD combinations. The accuracy of the intraoral scanners and extraoral scanner was clinically acceptable. Marginal and internal fit of the digital crowns fabricated using the intraoral scanner and CAD programs were inferior to those fabricated using the extraoral scanner and CAD programs.

Performance evaluation of 8 CT scanners for clinical use in Italy

International Nuclear Information System (INIS)

Pinto, I.; De Denaro, M.; Giribona, P.; Gicericin, C.; Bravar, D.

1988-01-01

In the past few years the use of CT scanners has widely spread in Italian care institutions. This methodology has thus become an important creates the need for an accurate study of the various aspects of the phenomenon, e.g. technological, diagnostic and economic. In order to evaluate the quality of the CT scanners used in our country, the majors suppliers of the Italian market were asked to provide us with a unit from their production. Six out of 7 companies complied with our request. A standard protocol was used to evaluate the performance of 8 CT scanners, currently used in Italy. The following parameters were evaluated: spatial resolution, contrast resolution, noise, slice thickness, uniformity, linearity and radiation dose. Five currently-used operating modalities were employed. The results allow an overall assessment of the performance of the 8 CT scanners

Transmitting Performance Evaluation of ASICs for CMUT-Based Portable Ultrasound Scanners

DEFF Research Database (Denmark)

Llimos Muntal, Pere; Diederichsen, Søren Elmin; Jørgensen, Ivan Harald Holger

2017-01-01

Portable ultrasound scanners (PUS) have, in recent years, raised a lot of attention, as they can potentially overcome some of the limitations of static scanners. However, PUS have a lot of design limitations including size and power consumption. These restrictions can compromise the image quality...... of the scanner. In order to overcome these restrictions, application specific integrated circuits (ASICs) are needed to implement the electronics. In this work, a comparative study of the transmitting performance of a capacitive micromachined ultrasonic transducer (CMUT) driven by a commercial generic ultrasound...

FE modeling of Cu wire bond process and reliability

NARCIS (Netherlands)

Yuan, C.A.; Weltevreden, E.R.; Akker, P. van den; Kregting, R.; Vreugd, J. de; Zhang, G.Q.

2011-01-01

Copper based wire bonding technology is widely accepted by electronic packaging industry due to the world-wide cost reduction actions (compared to gold wire bond). However, the mechanical characterization of copper wire differs from the gold wire; hence the new wire bond process setting and new bond

Monitoring and evaluation of wire mesh forming life

Science.gov (United States)

Enemuoh, Emmanuel U.; Zhao, Ping; Kadlec, Alec

2018-03-01

Forming tables are used with stainless steel wire mesh conveyor belts to produce variety of products. The forming tables will typically run continuously for several days, with some hours of scheduled downtime for maintenance, cleaning and part replacement after several weeks of operation. The wire mesh conveyor belts show large variation in their remaining life due to associated variations in their nominal thicknesses. Currently the industry is dependent on seasoned operators to determine the replacement time for the wire mesh formers. The drawback of this approach is inconsistency in judgements made by different operators and lack of data knowledge that can be used to develop decision making system that will be more consistent with wire mesh life prediction and replacement time. In this study, diagnostic measurements about the health of wire mesh former is investigated and developed. The wire mesh quality characteristics considered are thermal measurement, tension property, gage thickness, and wire mesh wear. The results show that real time thermal sensor and wear measurements would provide suitable data for the estimation of wire mesh failure, therefore, can be used as a diagnostic parameter for developing structural health monitoring (SHM) system for stainless steel wire mesh formers.

Active Damping of a Piezoelectric Tube Scanner using Self-Sensing Piezo Actuation

Science.gov (United States)

Kuiper, S.; Schitter, G.

2010-01-01

In most Atomic Force Microscopes (AFM), a piezoelectric tube scanner is used to position the sample underneath the measurement probe. Oscillations stemming from the weakly damped resonances of the tube scanner are a major source of image distortion, putting a limitation on the achievable imaging speed. This paper demonstrates active damping of these oscillations in multiple scanning axes without the need for additional position sensors. By connecting the tube scanner in a capacitive bridge circuit the scanner oscillations can be measured in both scanning axes, using the same piezo material as an actuator and sensor simultaneously. In order to compensate for circuit imbalance caused by hysteresis in the piezo element, an adaptive balancing circuit is used. The obtained measurement signal is used for feedback control, reducing the resonance peaks in both scanning axes by 18 dB and the cross-coupling at those frequencies by 30 dB. Experimental results demonstrate a significant reduction in scanner oscillations when applying the typical triangular scanning signals, as well as a strong reduction in coupling induced oscillations. Recorded AFM images show a considerable reduction in image distortion due to the proposed control method, enabling artifact free AFM imaging at a speed of 122 lines per second with a standard piezoelectric tube scanner. PMID:26412944

Radiation dose assessment in a 320-detector-row CT scanner used in cardiac imaging

International Nuclear Information System (INIS)

Goma, Carles; Ruiz, Agustin; Jornet, Nuria; Latorre, Artur; Pallerol, Rosa M.; Carrasco, Pablo; Eudaldo, Teresa; Ribas, Montserrat

2011-01-01

Purpose: In the present era of cone-beam CT scanners, the use of the standardized CTDI 100 as a surrogate of the idealized CTDI is strongly discouraged and, consequently, so should be the use of the dose-length product (DLP) as an estimate of the total energy imparted to the patient. However, the DLP is still widely used as a reference quantity to normalize the effective dose for a given scan protocol mainly because the CTDI 100 is an easy-to-measure quantity. The aim of this article is therefore to describe a method for radiation dose assessment in large cone-beam single axial scans, which leads to a straightforward estimation of the total energy imparted to the patient. The authors developed a method accessible to all medical physicists and easy to implement in clinical practice in an attempt to update the bridge between CT dosimetry and the estimation of the effective dose. Methods: The authors used commercially available material and a simple mathematical model. The method described herein is based on the dosimetry paradigm introduced by the AAPM Task Group 111. It consists of measuring the dose profiles at the center and the periphery of a long body phantom with a commercial solid-state detector. A weighted dose profile is then calculated from these measurements. To calculate the CT dosimetric quantities analytically, a Gaussian function was fitted to the dose profile data. Furthermore, the Gaussian model has the power to condense the z-axis information of the dose profile in two parameters: The single-scan central dose, f(0), and the width of the profile, σ. To check the energy dependence of the solid-state detector, the authors compared the dose profiles to measurements made with a small volume ion chamber. To validate the overall method, the authors compared the CTDI 100 calculated analytically to the measurement made with a 100 mm pencil ion chamber. Results: For the central and weighted dose profiles, the authors found a good agreement between the

Radiation dose assessment in a 320-detector-row CT scanner used in cardiac imaging

Energy Technology Data Exchange (ETDEWEB)

Goma, Carles; Ruiz, Agustin; Jornet, Nuria; Latorre, Artur; Pallerol, Rosa M.; Carrasco, Pablo; Eudaldo, Teresa; Ribas, Montserrat [Servei de Radiofisica i Radioproteccio, Hospital de la Santa Creu i Sant Pau, Sant Antoni Maria Claret 167, 08025 Barcelona (Spain)

2011-03-15

Purpose: In the present era of cone-beam CT scanners, the use of the standardized CTDI{sub 100} as a surrogate of the idealized CTDI is strongly discouraged and, consequently, so should be the use of the dose-length product (DLP) as an estimate of the total energy imparted to the patient. However, the DLP is still widely used as a reference quantity to normalize the effective dose for a given scan protocol mainly because the CTDI{sub 100} is an easy-to-measure quantity. The aim of this article is therefore to describe a method for radiation dose assessment in large cone-beam single axial scans, which leads to a straightforward estimation of the total energy imparted to the patient. The authors developed a method accessible to all medical physicists and easy to implement in clinical practice in an attempt to update the bridge between CT dosimetry and the estimation of the effective dose. Methods: The authors used commercially available material and a simple mathematical model. The method described herein is based on the dosimetry paradigm introduced by the AAPM Task Group 111. It consists of measuring the dose profiles at the center and the periphery of a long body phantom with a commercial solid-state detector. A weighted dose profile is then calculated from these measurements. To calculate the CT dosimetric quantities analytically, a Gaussian function was fitted to the dose profile data. Furthermore, the Gaussian model has the power to condense the z-axis information of the dose profile in two parameters: The single-scan central dose, f(0), and the width of the profile, {sigma}. To check the energy dependence of the solid-state detector, the authors compared the dose profiles to measurements made with a small volume ion chamber. To validate the overall method, the authors compared the CTDI{sub 100} calculated analytically to the measurement made with a 100 mm pencil ion chamber. Results: For the central and weighted dose profiles, the authors found a good

Electric wiring domestic

CERN Document Server

Coker, A J

1992-01-01

Electric Wiring: Domestic, Tenth Edition, is a clear and reliable guide to the practical aspects of domestic electric wiring. Intended for electrical contractors, installation engineers, wiremen and students, its aim is to provide essential up to date information on modern methods and materials in a simple, clear, and concise manner. The main changes in this edition are those necessary to bring the work into line with the 16th Edition of the Regulations for Electrical Installations issued by the Institution of Electrical Engineers. The book begins by introducing the basic features of domestic

Cyclone: A laser scanner for mobile robot navigation

Science.gov (United States)

Singh, Sanjiv; West, Jay

1991-09-01

Researchers at Carnegie Mellon's Field Robotics Center have designed and implemented a scanning laser rangefinder. The device uses a commercially available time-of-flight ranging instrument that is capable of making up to 7200 measurements per second. The laser beam is reflected by a rotating mirror, producing up to a 360 degree view. Mounted on a robot vehicle, the scanner can be used to detect obstacles in the vehicle's path or to locate the robot on a map. This report discusses the motivation, design, and some applications of the scanner.

Micro Wire-Drawing: Experiments And Modelling

International Nuclear Information System (INIS)

Berti, G. A.; Monti, M.; Bietresato, M.; D'Angelo, L.

2007-01-01

In the paper, the authors propose to adopt the micro wire-drawing as a key for investigating models of micro forming processes. The reasons of this choice arose in the fact that this process can be considered a quasi-stationary process where tribological conditions at the interface between the material and the die can be assumed to be constant during the whole deformation. Two different materials have been investigated: i) a low-carbon steel and, ii) a nonferrous metal (copper). The micro hardness and tensile tests performed on each drawn wire show a thin hardened layer (more evident then in macro wires) on the external surface of the wire and hardening decreases rapidly from the surface layer to the center. For the copper wire this effect is reduced and traditional material constitutive model seems to be adequate to predict experimentation. For the low-carbon steel a modified constitutive material model has been proposed and implemented in a FE code giving a better agreement with the experiments

Thermo-mechanical design of a CW sweep plate emittance scanner

International Nuclear Information System (INIS)

Rathke, J.; Peacock, M.; Sredniawski, J.

1996-01-01

A sweep plate emittance scanner for use with high power, continuous wave (CW) beams has been designed, fabricated and commissioned at Northrop Grumman. The design is capable of scanning beams of up to 20 kW beam power with a spot diameter as small as 2 cm. The scanner pod is mounted on a ball screw driven linear bearing table that is driven through the beam by a stepper motor at velocities up to 30 cm/sec. This paper presents the thermo-mechanical analysis of the pod moving through a gaussian beam and the details of the mechanical design of the pod and motion system. Analyses to determine scanner cooling schemes and structural materials are presented. (author)

Out of lab calibration of a rotating 2D scanner for 3D mapping

Science.gov (United States)

Koch, Rainer; Böttcher, Lena; Jahrsdörfer, Maximilian; Maier, Johannes; Trommer, Malte; May, Stefan; Nüchter, Andreas

2017-06-01

Mapping is an essential task in mobile robotics. To fulfil advanced navigation and manipulation tasks a 3D representation of the environment is required. Applying stereo cameras or Time-of-flight cameras (TOF cameras) are one way to archive this requirement. Unfortunately, they suffer from drawbacks which makes it difficult to map properly. Therefore, costly 3D laser scanners are applied. An inexpensive way to build a 3D representation is to use a 2D laser scanner and rotate the scan plane around an additional axis. A 3D point cloud acquired with such a custom device consists of multiple 2D line scans. Therefore the scanner pose of each line scan need to be determined as well as parameters resulting from a calibration to generate a 3D point cloud. Using external sensor systems are a common method to determine these calibration parameters. This is costly and difficult when the robot needs to be calibrated outside the lab. Thus, this work presents a calibration method applied on a rotating 2D laser scanner. It uses a hardware setup to identify the required parameters for calibration. This hardware setup is light, small, and easy to transport. Hence, an out of lab calibration is possible. Additional a theoretical model was created to test the algorithm and analyse impact of the scanner accuracy. The hardware components of the 3D scanner system are an HOKUYO UTM-30LX-EW 2D laser scanner, a Dynamixel servo-motor, and a control unit. The calibration system consists of an hemisphere. In the inner of the hemisphere a circular plate is mounted. The algorithm needs to be provided with a dataset of a single rotation from the laser scanner. To achieve a proper calibration result the scanner needs to be located in the middle of the hemisphere. By means of geometric formulas the algorithms determine the individual deviations of the placed laser scanner. In order to minimize errors, the algorithm solves the formulas in an iterative process. First, the calibration algorithm was

BEAM EMITTANCE MEASUREMENT TOOL FOR CEBAF OPERATIONS

International Nuclear Information System (INIS)

Chevtsov, Pavel; Tiefenback, Michael

2008-01-01

A new software tool was created at Jefferson Lab to measure the emittance of the CEBAF electron beams. The tool consists of device control and data analysis applications. The device control application handles the work of wire scanners and writes their measurement results as well as the information about accelerator settings during these measurements into wire scanner data files. The data analysis application reads these files and calculates the beam emittance on the basis of a wire scanner data processing model. Both applications are computer platform independent but are mostly used on LINUX PCs recently installed in the accelerator control room. The new tool significantly simplifies beam emittance measurement procedures for accelerator operations and contributes to a very high availability of the CEBAF machine for the nuclear physics program at Jefferson Lab.

Effect of the plasma production rate on the implosion dynamics of cylindrical wire/fiber arrays with a profiled linear mass

International Nuclear Information System (INIS)

Aleksandrov, V. V.; Mitrofanov, K. N.; Gritsuk, A. N.; Frolov, I. N.; Grabovski, E. V.; Laukhin, Ya. N.

2013-01-01

Results are presented from experimental studies on the implosion of arrays made of wires and metalized fibers under the action of current pulses with an amplitude of up to 3.5 MA at the Angara-5-1 facility. The effect of the parameters of an additional linear mass of bismuth and gold deposited on the wires/fibers is investigated. It is examined how the material of the wires/fibers and the metal coating deposited on them affect the penetration of the plasma with the frozen-in magnetic field into a cylindrical array. Information on the plasma production rate for different metals is obtained by analyzing optical streak images of imploding arrays. The plasma production rate m-dot m for cylindrical arrays made of the kapron fibers coated with bismuth is determined. For the initial array radius of R 0 = 1 cm and discharge current of I = 1 MA, the plasma production rate is found to be m-dot m approx. 0.095 ± 0.015 μg/(cm 2 ns)

Seeded perturbations in wire array Z-Pinches

International Nuclear Information System (INIS)

Robinson, Allen Conrad; Fedin, Dmitry; Kantsyrev, Victor Leonidovich; Wunsch, Scott Edward; Oliver, Bryan Velten; Lebedev, Sergey V.; Coverdale, Christine Anne; Ouart, Nicholas D.; LePell, Paul David; Safronova, Alla S.; Shrestha, I.; McKenney, John Lee; Ampleford, David J.; Rapley, J.; Bott, S.C.; Palmer, J.B.A.; Sotnikov, Vladimir Isaakovich; Bland, Simon Nicholas; Ivanov, Vladimir V.; Chittenden, Jeremy Paul; Jones, B.; Garasi, Christopher Joseph; Hall, Gareth Neville; Yilmaz, M. Faith; Mehlhorn, Thomas Alan; Deeney, Christopher; Pokala, S.; Nalajala, V.

2005-01-01

Controlled seeding of perturbations is employed to study the evolution of wire array z-pinch implosion instabilities which strongly impact x-ray production when the 3D plasma stagnates on axis. Wires modulated in radius exhibit locally enhanced magnetic field and imploding bubble formation at discontinuities in wire radius due to the perturbed current path. Wires coated with localized spectroscopic dopants are used to track turbulent material flow. Experiments and MHD modeling offer insight into the behavior of z-pinch instabilities.

DT fusion neutron irradiation of LLL Nb3Sn and LLL superconductor wires at 4.20K

International Nuclear Information System (INIS)

MacLean, S.C.

1977-01-01

The DT fusion neutron irradiation of one LLL superconductor wire and one LLL Nb 3 Sn foil at 4.2 0 K is described. The sample position, beam-on time, and neutron dose record are given. The results from two ''profile'' dosimetry foils measuring the lateral variation in neutron flux are included

Perancangan dan Pembuatan Alat Scanner 3D Menggunakan Sensor Kinect Xbox 360

Directory of Open Access Journals (Sweden)

Arif Armansyah

2018-04-01

Full Text Available Abstrak Scanner 3D adalah teknologi yang digunakan untuk memindai objek nyata untuk mendapatkan bentuk, ukuran dan fitur lainnya agar menghasilkan gambar yang sangat akurat. Dalam perancangan alat scanner 3D sebelumnya, yaitu scanner 3D menggunakan sensor ultrasonik, infra merah, dan line laser. Maka dapat disimpulkan terdapat beberapa kekurangan yaitu masih terbatasnya objek yang di scan serta hasil scan yang belum akurat karena hanya menghasilkan garis-garis yang membentuk objek. Pada penelitian ini, penulis membuat scanner 3D dengan hasil akurasi yang tinggi. Scanner 3D yang dibuat adalah menggunakan sensor Kinect xbox 360. Cara kerja dari kinect yaitu dengan menggabungkan antara beberapa kamera, Color Cimos (VNA38209015 kamera ini berfungsi membantu dalam pengenalan objek dan fitur deteksi lainnya, serta kamera IR CMOS (VCA379C7130, dan IR Projector (OG12 yaitu sebagai depth sensor atau sensor kedalaman yang merupakan sebuah proyektor infrared dan sebuah sensor monochrome CMOS yang bekerja secara bersama-sama untuk melihat ruangan atau area dalam bentuk 3D tanpa memperdulikan kondisi cahaya. Untuk mengolah serta menampilkan hasil dari objek yang sudah di scan menggunakan aplikasi KScan3D. Kemudian untuk koneksi antara PC dengan media penggerak menggunakan Bluetooth HC-06. Setelah dilakukan pengujian didapatkan model gambar 3D dengan dengan hasil akurasi yang cukup tinggi. Kata Kunci: Bluetooth HC-06, Infra Merah, Line Laser, Kinect, KScan3D, Scanner 3D, Ultrasonik Abstract Scanner 3D is the technology used to scan real objects to get the form, size and other features in order to produce pictures that are very accurate. In the design of the appliance scanner 3D previously, namely scanner 3D using the ultrasonic sensor, infrared and laser line. It can be concluded there are some disadvantages that is still limited objects in the scan and the scans are not accurate because only produces lines that formed the object. In this research, author

Fast neutron radiography scanner for the detection of contraband in air cargo containers

International Nuclear Information System (INIS)

Eberhardt, J.E.; Rainey, S.; Stevens, R.J.; Sowerby, B.D.; Tickner, J.R.

2005-01-01

There is a growing need to rapidly scan bulk air cargo for contraband such as illicit drugs and explosives. The Commonwealth Science and Industrial Research Organisation (CSIRO) have been working with Australian Customs Service to develop a scanner capable of directly scanning airfreight containers in 1-2 minutes without unpacking. The scanner combines fast neutron and gamma-ray radiography to provide high-resolution images that include information on material composition. A full-scale prototype scanner has been successfully tested in the laboratory and a commercial-scale scanner is due to be installed at Brisbane airport in 2005

Fast neutron radiography scanner for the detection of contraband in air cargo containers

Energy Technology Data Exchange (ETDEWEB)

Eberhardt, J.E. [CSIRO Minerals, Private Mail Bag 5, Menai, NSW 2234 (Australia); Rainey, S. [CSIRO Minerals, Private Mail Bag 5, Menai, NSW 2234 (Australia); Stevens, R.J. [CSIRO Minerals, Private Mail Bag 5, Menai, NSW 2234 (Australia); Sowerby, B.D. [CSIRO Minerals, Private Mail Bag 5, Menai, NSW 2234 (Australia)]. E-mail: brian.sowerby@csiro.au; Tickner, J.R. [CSIRO Minerals, Private Mail Bag 5, Menai, NSW 2234 (Australia)

2005-08-01

There is a growing need to rapidly scan bulk air cargo for contraband such as illicit drugs and explosives. The Commonwealth Science and Industrial Research Organisation (CSIRO) have been working with Australian Customs Service to develop a scanner capable of directly scanning airfreight containers in 1-2 minutes without unpacking. The scanner combines fast neutron and gamma-ray radiography to provide high-resolution images that include information on material composition. A full-scale prototype scanner has been successfully tested in the laboratory and a commercial-scale scanner is due to be installed at Brisbane airport in 2005.

29 CFR 1926.404 - Wiring design and protection.

Science.gov (United States)

2010-07-01

.... Receptacles on a two-wire, single-phase portable or vehicle-mounted generator rated not more than 5kW, where the circuit conductors of the generator are insulated from the generator frame and all other grounded... wiring shall be grounded: (i) Three-wire DC systems. All 3-wire DC systems shall have their neutral...

A fast ADC scanner for multiparameter nuclear physics experiments

International Nuclear Information System (INIS)

Midttun, G.; Ingebretsen, F.; Holt, K.; Skaali, B.

1983-04-01

A fast readout system for multiparameter experiments in nuclear physics is described. The central part of the CAMAC aquisition hardware is an ADC scanner module. The scanner incorporates a new arbitration logic and direct memory access for simultaneous transfer of singles and correlated data. Together with specially designed ADC interfaces the system can be set up for any configuration of singles and multiparameter events from 1 up to 15 ADC's in one crate

A fast ADC scanner for multiparameter nuclear physics experiments

International Nuclear Information System (INIS)

Midttun, G.; Holt, K.; Ingebretsen, F.; Skaali, B.

1983-01-01

A fast readout system for multiparameter experiments in nuclear physics is described. The central part of the CAMAC aquisition hardware is an ADC scanner module. The scanner incorporates a new arbitration logic and direct memory access for simultaneous transfer of singles and correlated data. Together with specially designed ADC interfaces the system can be set up for any configurations of singles and multiparameter events from 1 up to 15 ADC's in one crate

Acoustic Emission from Elevator Wire Ropes During Tensile Testing

Science.gov (United States)

Bai, Wenjie; Chai, Mengyu; Li, Lichan; Li, Yongquan; Duan, Quan

The acoustic emission (AE) technique was used to monitor the tensile testing process for two kinds of elevator wire ropes in our work. The AE signals from wire breaks were obtained and analyzed by AE parameters and waveforms. The results showed that AE technique can be a useful tool to monitor wire break phenomenon of wire ropes and effectively capture information of wire break signal. The relationship between AE signal characteristics and wire breaks is investigated and it is found that the most effective acoustic signal discriminators are amplitude and absolute energy. Moreover, the wire break signal of two kinds of ropes is a type of burst signal and it is believed that the waveform and spectrum can be applied to analyze the AE wire break signals.

A Cross-Platform Smartphone Brain Scanner

DEFF Research Database (Denmark)

Larsen, Jakob Eg; Stopczynski, Arkadiusz; Stahlhut, Carsten

We describe a smartphone brain scanner with a low-costwireless 14-channel Emotiv EEG neuroheadset interfacingwith multiple mobile devices. This personal informaticssystem enables minimally invasive and continuouscapturing of brain imaging data in natural settings. Thesystem applies an inverse...

Superconducting wires and methods of making thereof

Energy Technology Data Exchange (ETDEWEB)

Xu, Xingchen; Sumption, Michael D.; Peng, Xuan

2018-03-13

Disclosed herein are superconducting wires. The superconducting wires can comprise a metallic matrix and at least one continuous subelement embedded in the matrix. Each subelement can comprise a non-superconducting core, a superconducting layer coaxially disposed around the non-superconducting core, and a barrier layer coaxially disposed around the superconducting layer. The superconducting layer can comprise a plurality of Nb.sub.3Sn grains stabilized by metal oxide particulates disposed therein. The Nb.sub.3Sn grains can have an average grain size of from 5 nm to 90 nm (for example, from 15 nm to 30 nm). The superconducting wire can have a high-field critical current density (J.sub.c) of at least 5,000 A/mm.sup.2 at a temperature of 4.2 K in a magnetic field of 12 T. Also described are superconducting wire precursors that can be heat treated to prepare superconducting wires, as well as methods of making superconducting wires.

Robotic Prostate Biopsy in Closed MRI Scanner

National Research Council Canada - National Science Library

Fischer, Gregory

2008-01-01

.... This work enables prostate brachytherapy and biopsy procedures in standard high-field diagnostic MRI scanners through the development of a robotic needle placement device specifically designed...

Body of Knowledge (BOK) for Copper Wire Bonds

Science.gov (United States)

Rutkowski, E.; Sampson, M. J.

2015-01-01

Copper wire bonds have replaced gold wire bonds in the majority of commercial semiconductor devices for the latest technology nodes. Although economics has been the driving mechanism to lower semiconductor packaging costs for a savings of about 20% by replacing gold wire bonds with copper, copper also has materials property advantages over gold. When compared to gold, copper has approximately: 25% lower electrical resistivity, 30% higher thermal conductivity, 75% higher tensile strength and 45% higher modulus of elasticity. Copper wire bonds on aluminum bond pads are also more mechanically robust over time and elevated temperature due to the slower intermetallic formation rate - approximately 1/100th that of the gold to aluminum intermetallic formation rate. However, there are significant tradeoffs with copper wire bonding - copper has twice the hardness of gold which results in a narrower bonding manufacturing process window and requires that the semiconductor companies design more mechanically rigid bonding pads to prevent cratering to both the bond pad and underlying chip structure. Furthermore, copper is significantly more prone to corrosion issues. The semiconductor packaging industry has responded to this corrosion concern by creating a palladium coated copper bonding wire, which is more corrosion resistant than pure copper bonding wire. Also, the selection of the device molding compound is critical because use of environmentally friendly green compounds can result in internal CTE (Coefficient of Thermal Expansion) mismatches with the copper wire bonds that can eventually lead to device failures during thermal cycling. Despite the difficult problems associated with the changeover to copper bonding wire, there are billions of copper wire bonded devices delivered annually to customers. It is noteworthy that Texas Instruments announced in October of 2014 that they are shipping microcircuits containing copper wire bonds for safety critical automotive applications

Development of high pressure pipe scanners

International Nuclear Information System (INIS)

Kim, Jae H.; Lee, Jae C.; Moon, Soon S.; Eom, Heung S.; Choi, Yu R.

1998-12-01

This report describes an automatic ultrasonic scanning system for pressure pipe welds, which was developed in this project using recent advanced technologies on mobile robot and computer. The system consists of two modules: a robot scanner module which navigates and manipulates scanning devices, and a data acquisition module which generates ultrasonic signal and processes the data from the scanner. The robot has 4 magnetic wheels and 2 -axis manipulator on which ultrasonic transducer attached. The wheeled robot can navigate curved surface such as outer wall of circular pipes. Magnetic wheels were optimally designed through magnetic field analysis. Free surface sensing and line tracking control algorithm were developed and implemented, and the control devices and software can be used in practical inspection works. We expect our system can contribute to reduction of inspection time, performance enhancement, and effective management of inspection results

Obstacle negotiation control for a mobile robot suspended on overhead ground wires by optoelectronic sensors

Science.gov (United States)

Zheng, Li; Yi, Ruan

2009-11-01

Power line inspection and maintenance already benefit from developments in mobile robotics. This paper presents mobile robots capable of crossing obstacles on overhead ground wires. A teleoperated robot realizes inspection and maintenance tasks on power transmission line equipment. The inspection robot is driven by 11 motor with two arms, two wheels and two claws. The inspection robot is designed to realize the function of observation, grasp, walk, rolling, turn, rise, and decline. This paper is oriented toward 100% reliable obstacle detection and identification, and sensor fusion to increase the autonomy level. An embedded computer based on PC/104 bus is chosen as the core of control system. Visible light camera and thermal infrared Camera are both installed in a programmable pan-and-tilt camera (PPTC) unit. High-quality visual feedback rapidly becomes crucial for human-in-the-loop control and effective teleoperation. The communication system between the robot and the ground station is based on Mesh wireless networks by 700 MHz bands. An expert system programmed with Visual C++ is developed to implement the automatic control. Optoelectronic laser sensors and laser range scanner were installed in robot for obstacle-navigation control to grasp the overhead ground wires. A novel prototype with careful considerations on mobility was designed to inspect the 500KV power transmission lines. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

Numerical modelling of ozone production in a wire-cylinder corona discharge and comparison with a wire-plate corona discharge

International Nuclear Information System (INIS)

Wang Pengxiang; Chen Junhong

2009-01-01

The effect of electrode configuration on ozone production in the direct-current corona discharge of dry and humid air is studied by a numerical model that combines the electron distribution in the corona plasma, plasma chemistry and transport phenomena. Two electrode configurations are considered: wire-cylinder discharge with air flowing along the wire axis and wire-plate discharge with air flowing transverse to the wire. The ozone distributions in both types of discharges are compared. For both electrode configurations, the ozone production rate is higher in the negative corona than in the positive corona and it decreases with an increase in relative humidity. More importantly, the detailed ozone distribution in the neighbourhood of the discharge wire, together with the ozone kinetics, reveals the possible difference in the ozone production from the two discharges. With the same operating conditions and sufficiently short flow residence time, the ozone production rate is nearly the same for both electrode configurations. When the flow residence time is longer than the characteristic time for homogeneous ozone destruction, the net ozone production is higher in the wire-cylinder discharge than in the wire-plate discharge due to relatively less ozone destruction.

Numerical modelling of ozone production in a wire-cylinder corona discharge and comparison with a wire-plate corona discharge

Science.gov (United States)

Wang, Pengxiang; Chen, Junhong

2009-02-01

The effect of electrode configuration on ozone production in the direct-current corona discharge of dry and humid air is studied by a numerical model that combines the electron distribution in the corona plasma, plasma chemistry and transport phenomena. Two electrode configurations are considered: wire-cylinder discharge with air flowing along the wire axis and wire-plate discharge with air flowing transverse to the wire. The ozone distributions in both types of discharges are compared. For both electrode configurations, the ozone production rate is higher in the negative corona than in the positive corona and it decreases with an increase in relative humidity. More importantly, the detailed ozone distribution in the neighbourhood of the discharge wire, together with the ozone kinetics, reveals the possible difference in the ozone production from the two discharges. With the same operating conditions and sufficiently short flow residence time, the ozone production rate is nearly the same for both electrode configurations. When the flow residence time is longer than the characteristic time for homogeneous ozone destruction, the net ozone production is higher in the wire-cylinder discharge than in the wire-plate discharge due to relatively less ozone destruction.

Fabrication of tungsten wire needles

International Nuclear Information System (INIS)

Roder, A.

1983-02-01

Fine point needles for field emissoin are conventionally produced by electrolytically or chemically etching tungsten wire. Points formed in this manner have a typical tip radius of about 0.5 microns and a cone angle of some 30 degrees. The construction of needle matrix detector chambers has created a need for tungsten needles whose specifications are: 20 mil tungsten wire, 1.5 inch total length, 3 mm-long taper (resulting in a cone angle of about 5 degrees), and 25 micron-radius point (similar to that found on sewing needles). In the process described here for producing such needles, tungsten wire, immersed in a NaOH solution and in the presence of an electrode, is connected first to an ac voltage and then to a dc supply, to form a taper and a point on the end of the wire immersed in the solution. The process parameters described here are for needles that will meet the above specifications. Possible variations will be discussed under each approprite heading

Analysis of the Performance of a Laser Scanner for Predictive Automotive Applications

Science.gov (United States)

Zeisler, J.; Maas, H.-G.

2015-08-01

In this paper we evaluate the use of a laser scanner for future advanced driver assistance systems. We focus on the important task of predicting the target vehicle for longitudinal ego vehicle control. Our motivation is to decrease the reaction time of existing systems during cut-in maneuvers of other traffic participants. A state-of-the-art laser scanner, the Ibeo Scala B2 R , is presented, providing its sensing characteristics and the subsequent high level object data output. We evaluate the performance of the scanner towards object tracking with the help of a GPS real time kinematics system on a test track. Two designed scenarios show phases with constant distance and velocity as well as dynamic motion of the vehicles. We provide the results for the error in position and velocity of the scanner and furthermore, review our algorithm for target vehicle prediction. Finally we show the potential of the laser scanner with the estimated error, that leads to a decrease of up to 40% in reaction time with best conditions.

Transverse beam profile measurements with slit scanner and Faraday cup at REX-ISOLDE

CERN Document Server

Cantero, E D; Lanaia, D; Sosa, A; Voulot, D

2014-01-01

The transverse profiles for the HIE-ISOLDE beams will be measured using a system composed of a scanning slit and a Faraday cup. A validation test of the proposed device was performed using the REX-ISOLDE stable beam and a prototype diagnostic box designed for HIE-ISOLDE. The slit used for this test was very thin (0.2 mm width), but still fairly good profiles could be obtained for beams with total current of around 20 pA (typical beam intensity during normal set-up procedures for REX-ISOLDE).

A new generation of PET scanners for small animal studies

International Nuclear Information System (INIS)

Hegyesi, G.; Imrek, J.; Kalinka, G.; Molnar, J.; Novak, D.; Valastyan, I.; Balkay, L.; Emri, M.; Kis, S.; Tron, L.

2008-01-01

Complete text of publication follows. Research on small animal PET scanners has been a hot topic in recent years. These devices are used in the preclinical phases of drug tests and during the development of new radiopharmaceuticals. They also provide a cost efficient way to test new materials, new design concepts and new technologies that later can be used to build more efficient human medical imaging devices. The development of a PET scanner requires expertise on different fields, therefore a consortium was formed that brought together Hungarian academic and industrial partners: the Nuclear Research Institute (which has experience in the development of nuclear detectors and data acquisition systems), the PET Center of the University of Debrecen (which has clinical experience in the application of nuclear imaging devices and background in image processing software), Mediso Ltd. (which has been developing, manufacturing, selling and servicing medical imaging devices since 1990) and other academic partners. This consortium has been working together since 2003: the knowledge base acquired during the development of our small animal PET scanners (miniPET-I and miniPET-II) is now being utilized to build a commercial multimodal human PET scanner. The operation of a PET scanner is based on the simultaneous detection ('coincidence') of two gamma photons originating from a positron annihilation. In traditional PET scanners coincidence is detected by a central unit during the measurement. In our system there is no such central module: all detected single gamma events are recorded (list mode data acquisition), and the list of events are processed using a computer cluster (built from PCs). The usage of independent detector modules and commercial components reduce both development and maintenance costs. Also, this mode of data acquisition is more suitable for development purposes, since once the data is collected and stored it can be used many times to test different signal

Transverse emittance measurement and preservation at the LHC

Energy Technology Data Exchange (ETDEWEB)

Kuhn, Maria

2016-06-20

The Large Hadron Collider (LHC) at CERN is a high energy storage ring that provides proton and heavy ion collisions to study fundamental particle physics. The luminosity production is closely linked to emittance preservation in the accelerator. The transverse emittance is the phase space density of the beam and should be conserved when the particle beam is transformed through the accelerator. Perturbing effects, however, can lead to emittance increase and hence luminosity degradation. Measuring the emittance growth is a complex task with high intensity beams and changing energies. The machine optics and the transverse beam size have to be measured as accurately as possible. Beta function measurements with k-modulation are discussed. With this method the quadrupole focussing strength is varied and the resulting tune change is traced to determine the beta function at the quadrupole. A new k-modulation measurement tool was developed for the LHC. The fully automatic and online measurement system takes constraints of various systems such as tune measurement precision and powering limitations of the LHC superconducting circuits into account. With sinusoidal k-modulation record low beta function measurement uncertainties in the LHC have been reached. 2015 LHC beta function and β*, which is the beta function at the collision point, measurements with k-modulation will be presented. Wire scanners and synchrotron light monitors are presently used in the LHC to measure the transverse beam size. Accuracy and limitations of the LHC transverse profile monitors are discussed. During the 2012 LHC proton run it was found that wire scanner photomultiplier saturation added significant uncertainty on all measurements. A large discrepancy between emittances from wire scanners and luminosity was discovered but not solved. During Long Shutdown 1 the wire scanner system was upgraded with new photomultipliers. A thorough study of LHC wire scanner measurement precision in 2015 is presented

A dedicated tool for PET scanner simulations using FLUKA

International Nuclear Information System (INIS)

Ortega, P.G.; Boehlen, T.T.; Cerutti, F.; Chin, M.P.W.; Ferrari, A.; Mancini, C.; Vlachoudis, V.; Mairani, A.; Sala, Paola R.

2013-06-01

Positron emission tomography (PET) is a well-established medical imaging technique. It is based on the detection of pairs of annihilation gamma rays from a beta+-emitting radionuclide, usually inoculated in the body via a biologically active molecule. Apart from its wide-spread use for clinical diagnosis, new applications are proposed. This includes notably the usage of PET for treatment monitoring of radiation therapy with protons and ions. PET is currently the only available technique for non-invasive monitoring of ion beam dose delivery, which was tested in several clinical pilot studies. For hadrontherapy, the distribution of positron emitters, produced by the ion beam, can be analyzed to verify the correct treatment delivery. The adaptation of previous PET scanners to new environments and the necessity of more precise diagnostics by better image quality triggered the development of new PET scanner designs. The use of Monte Carlo (MC) codes is essential in the early stages of the scanner design to simulate the transport of particles and nuclear interactions from therapeutic ion beams or radioisotopes and to predict radiation fields in tissues and radiation emerging from the patient. In particular, range verification using PET is based on the comparison of detected and simulated activity distributions. The accuracy of the MC code for the relevant physics processes is obviously essential for such applications. In this work we present new developments of the physics models with importance for PET monitoring and integrated tools for PET scanner simulations for FLUKA, a fully-integrated MC particle-transport code, which is widely used for an extended range of applications (accelerator shielding, detector and target design, calorimetry, activation, dosimetry, medical physics, radiobiology, ...). The developed tools include a PET scanner geometry builder and a dedicated scoring routine for coincident event determination. The geometry builder allows the efficient

External wire-frame fixation of digital skin grafts: a non-invasive alternative to the K-wire insertion method.

Science.gov (United States)

Huang, Chenyu; Ogawa, Rei; Hyakusoku, Hiko

2014-08-01

The current skin graft fixation methods for digits, including the Kirschner wire insertion technique, can be limited by inadequate or excessive fixation and complications such as infection or secondary injuries. Therefore, the external wire-frame fixation method was invented and used for skin grafting of digits. This study aimed to investigate external wire-frame fixation of digital skin grafts as a non-invasive alternative to the K-wire insertion method. In 2005-2012, 15 patients with burn scar contractures on the hand digits received a skin graft that was then fixed with an external wire frame. The intra-operative time needed to make the wire frame, the postoperative time to frame and suture removal, the graft survival rate, the effect of contracture release and the complications were recorded. In all cases, the contracture release was 100%. The complete graft survival rate was 98.6%. Four patients had epithelial necrosis in wire-frame fixation is simple, minimally invasive and a custom-made technique for skin grafting of the fingers. It was designed for its potential benefits and the decreased risk it poses to patients with scar contractures on their fingers. It can be implemented in three phases of grafting, does not affect the epiphyseal line or subsequent finger growth and is suitable for children with multi-digit involvement. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

Large angle and high linearity two-dimensional laser scanner based on voice coil actuators

Science.gov (United States)

Wu, Xin; Chen, Sihai; Chen, Wei; Yang, Minghui; Fu, Wen

2011-10-01

A large angle and high linearity two-dimensional laser scanner with an in-house ingenious deflection angle detecting system is developed based on voice coil actuators direct driving mechanism. The specially designed voice coil actuators make the steering mirror moving at a sufficiently large angle. Frequency sweep method based on virtual instruments is employed to achieve the natural frequency of the laser scanner. The response shows that the performance of the laser scanner is limited by the mechanical resonances. The closed-loop controller based on mathematical model is used to reduce the oscillation of the laser scanner at resonance frequency. To design a qualified controller, the model of the laser scanner is set up. The transfer function of the model is identified with MATLAB according to the tested data. After introducing of the controller, the nonlinearity decreases from 13.75% to 2.67% at 50 Hz. The laser scanner also has other advantages such as large deflection mirror, small mechanical structure, and high scanning speed.

Formation of plasma around wire fragments created by electrically exploded copper wire

International Nuclear Information System (INIS)

Taylor, Michael J.

2002-01-01

The physical processes occurring during the electrical explosion of metallic conductors has attracted interest for many years. Applications include circuit breakers, segmented lightning divertor strips for aircraft radomes, disruption of metallic shaped charge jets, plasma armatures for electromagnetic railguns and plasma generators for electrothermal-chemical guns. Recent work has cited the phenomenology of the fragmentation processes, particularly the development of a plasma around the lower resistance condensed fragments. An understanding of both the fragmentation process and the development of the accompanying formation of plasma is essential for the optimization of devices that utilize either of these phenomena. With the use of x-radiography and fast photography, this paper explores the wire explosion process, in particular the relationship between the fragmentation, plasma development and resistance rise that occurs during this period. A hypothesis is put forward to account for the development of plasma around the condensed wire fragments. Experimental parameters used in this study are defined. Wires studied were typically copper, with a diameter of 1 mm and length in excess of 150 mm. Circuit inductance used were from 26 to 800 μH. This relatively high circuit inductance gave circuit rise times less than 180 MA s -1 , slow with respect to many other exploding wire studies. Discharge duration ranged from 0.8 to 10 ms. (author)

Ferromagnetic artificial pinning centers in multifilamentary superconducting wires

International Nuclear Information System (INIS)

Wang, J.Q.; Rizzo, N.D.; Prober, D.E.

1997-01-01

The authors fabricated multifilamentary NbTi wires with ferromagnetic (FM) artificial pinning centers (APCs) to enhance the critical current density (J c ) in magnetic fields. They used a bundle and draw technique to process the APC wires with either Ni or Fe as the pinning centers. Both wires produced higher J c in the high field range (5-9 T) than previous non-magnetic APC wires similarly processed, even though the authors have not yet optimized pin percentage. Using a magnetometer they found that the pins remained ferromagnetic for the wires with maximum J c . However, they did observe a substantial loss of FM material for the wires where the pin diameter approached 3 nm. Thus, they expect further enhancement of J c with better pin quality

Ultrahigh-strength submicron-sized metallic glass wires

International Nuclear Information System (INIS)

Wang, Y.B.; Lee, C.C.; Yi, J.; An, X.H.; Pan, M.X.; Xie, K.Y.; Liao, X.Z.; Cairney, J.M.; Ringer, S.P.; Wang, W.H.

2014-01-01

In situ deformation experiments were performed in a transmission electron microscope to investigate the mechanical properties of submicron-sized Pd 40 Cu 30 Ni 10 P 20 metallic glass (MG) wires. Results show that the submicron-sized MG wires exhibit intrinsic ultrahigh tensile strength of ∼2.8 GPa, which is nearly twice as high as that in their bulk counterpart, and ∼5% elastic strain approaching the elastic limits. The tensile strength, engineering strain at failure and deformation mode of the submicron-sized MG wires depend on the diameter of the wires

Does the Use of Body Scanners Discriminate Overweight Flight Passengers? The Effect of Body Scanners on Body Image

Directory of Open Access Journals (Sweden)

Magdalena Laib

2016-06-01

Full Text Available Whereas the introduction of body scanners at airports has been accompanied by critical voices raising concerns that body scanners might have a negative impact on different minority groups, it has not been investigated thus far whether they might also have negative impacts on the average flight passenger and if the provision of adequate information might attenuate such negative impacts. Using a pre/post-design the current study examines the effect of a body scan in a controlled laboratory setting on the explicit and implicit body image of normal-weight and overweight people as assessed by questionnaires and an Implicit Association Test. Half of the sample received an information sheet concerning body scanners before they were scanned. While there was a negative impact of the body scan on the implicit body image of overweight participants, there was a positive impact on their explicit body image. The negative effect of the body scan was unaffected by receiving information. This study demonstrates that body scans do not only have negative effects on certain minority groups but potentially on a large proportion of the general public which suggests a critical reconsideration of the control procedures at airports, the training of the airport staff who is in charge of these procedures and the information flight passengers get about these procedures.

Unsteady pressures on a blunt trailing edge measured with an embedded pressure scanner

Science.gov (United States)

Naughton, Jonathan; Nikoueeyan, Pourya; Hind, Michael; Strike, John; Dahland, Matz; Keeter, Steven

2017-11-01

Development of direct-mount pressure scanners can decrease the pneumatic tubing length required to connect the measurement ports to the scanner manifold resulting in improved dynamic range for unsteady pressure measurements. In this work, the performance of a direct-mount pressure scanner for time-resolved pressure measurement is demonstrated in a well-established flow; the pressure fluctuations near the base of flat plate is considered. The additive manufactured model is instrumented with a pressure scanner and flush-mounted high-speed pressure transducers. The configuration of the ports on the model allows for side-by-side comparison of the pressures measured via embedded pneumatic tubing routed to a pressure scanner with that measured by high-speed transducers. Prior to testing, the dynamic response of each embedded pressure port is dynamically calibrated via an in-situ calibration technique. Pressure data is then acquired for fixed angle-of-attack and different dynamic pitching conditions. The dynamic range of the measurements acquired via direct-mount scanner will be compared to those acquired by the high speed transducers for both static and dynamic pitching configurations. The uncertainties associated with Weiner deconvolution are also quantified for the measurements.

Diamond wire cutting of heat exchangers

International Nuclear Information System (INIS)

Beckman, T.R.; Bjerler, J.

1991-01-01

With the change-out of equipment at nuclear power plants comes large quantities of low level contaminated metallic waste. Of particular concern are large heat exchangers, preheaters and steam generators. These bulky items consume huge volumes of burial space. The need for volume reduction and recycling of these metals has created new demands for 'how' to cut heat exchangers into useful sizes for decontamination, melting or compaction. This paper reviews the cutting solution provided by a diamond wire system, with particular regard for cutting of a Ringhals Preheater Bundle at Studsvik Nuclear in 1989. The background of diamond wire sawing is discussed and basic components of wire sawing are explained. Other examples of wire cutting decommissioned components are also given. (author)

The status of commercial and developmental HTS wires

Energy Technology Data Exchange (ETDEWEB)

Masur, L.J.; Buczek, D.; Harley, E.; Kodenkandath, T.; Li, X.; Lynch, J.; Nguyen, N.; Rupich, M.; Schoop, U.; Scudiere, J.; Siegal, E.; Thieme, C.; Verebelyi, D.; Zhang, W.; Kellers, J

2003-10-15

This paper provides an update on the development, performance and application of first and second generation high temperature superconductor (HTS) wires fabricated at American Superconductor (AMSC). First generation, multifilamentary composite wire is available commercially today in different viable product forms. This conductor carries 140 x the current of copper of the same cross-section, and is robust enough to stand tough industrial requirements. Second generation HTS wires, having a coated conductor composite architecture, are under development today and achieved substantial progress recently. AMSC's first generation wire will continue as the workhorse of the industry for the next 3-4 years while AMSC's second generation coated conductor wire is on track to be reproducible, uniform, scalable, and low cost. This paper provides a product differentiation with a view on the application of HTS wire in the electric power sector. Basic engineering data is reviewed that shall aid the engineer in the selection of the HTS wire product.

Wired to freedom

DEFF Research Database (Denmark)

Jepsen, Kim Sune Karrasch; Bertilsson, Margareta

2017-01-01

dimension of life science through a notion of public politics adopted from the political theory of John Dewey. We show how cochlear implantation engages different social imaginaries on the collective and individual levels and we suggest that users share an imaginary of being “wired to freedom” that involves...... new access to social life, continuous communicative challenges, common practices, and experiences. In looking at their lives as “wired to freedom,” we hope to promote a wider spectrum of civic participation in the benefit of future life science developments within and beyond the field of Cochlear...

The design of the detector and collimators for a hybrid scanner

International Nuclear Information System (INIS)

Vauramo, E.; Virjo, A.

1977-01-01

The hybrid scanner is a scanning device in which a long crystal with two or more photomultiplier (PM) tubes acts as a gamma camera along the crystal axis; the device acts as a linear scanner in a direction perpendicular to the crystal axis. A detailed analysis of the intrinsic resolution and uniformity is given for a two-PM-tube hybrid scanner (with one PM tube at each end) and the expressions derived should help the designer to choose the best crystal system. Collimation theory is discussed for the general hybrid scanner. Expressions and graphs are given to help in the design of a collimator with the best balance between the conflicting requirements of resolution, sensitivity, depth independence and freedom from artifacts (collimator holes may be seen in the image at high energy). Examples of practical collimators are given for energies of 80 to 140, 364, 511, 662 and 840 keV. (author)

Heat Transfer Analysis in Wire Bundles for Aerospace Vehicles

Science.gov (United States)

Rickman, S. L.; Iamello, C. J.

2016-01-01

Design of wiring for aerospace vehicles relies on an understanding of "ampacity" which refers to the current carrying capacity of wires, either, individually or in wire bundles. Designers rely on standards to derate allowable current flow to prevent exceedance of wire temperature limits due to resistive heat dissipation within the wires or wire bundles. These standards often add considerable margin and are based on empirical data. Commercial providers are taking an aggressive approach to wire sizing which challenges the conventional wisdom of the established standards. Thermal modelling of wire bundles may offer significant mass reduction in a system if the technique can be generalized to produce reliable temperature predictions for arbitrary bundle configurations. Thermal analysis has been applied to the problem of wire bundles wherein any or all of the wires within the bundle may carry current. Wire bundles present analytical challenges because the heat transfer path from conductors internal to the bundle is tortuous, relying on internal radiation and thermal interface conductance to move the heat from within the bundle to the external jacket where it can be carried away by convective and radiative heat transfer. The problem is further complicated by the dependence of wire electrical resistivity on temperature. Reduced heat transfer out of the bundle leads to higher conductor temperatures and, hence, increased resistive heat dissipation. Development of a generalized wire bundle thermal model is presented and compared with test data. The steady state heat balance for a single wire is derived and extended to the bundle configuration. The generalized model includes the effects of temperature varying resistance, internal radiation and thermal interface conductance, external radiation and temperature varying convective relief from the free surface. The sensitivity of the response to uncertainties in key model parameters is explored using Monte Carlo analysis.

Thermosonic wire bonding of gold wire onto copper pad using the saturated interfacial phenomena

Science.gov (United States)

Jeng, Yeau-Ren; Aoh, Jong-Hing; Wang, Chang-Ming

2001-12-01

Copper has been used to replace conventional aluminium interconnection to improve the performance of deep submicron integrated circuits. This study used the saturated interfacial phenomena found in thermosonic ball bonding of gold wire onto aluminium pad to investigate thermosonic ball bonding of gold wire onto copper pad. The effects of preheat temperatures and ultrasonic powers on the bonding force were investigated by using a thermosonic bonding machine and a shear tester. This work shows that under proper preheat temperatures, the bonding force of thermosonic wire bonding can be explained based on interfacial microcontact phenomena such as energy intensity, interfacial temperature and real contact area. It is clearly shown that as the energy intensity is increased, the shear force increases, reaches a maximum, and then decreases. After saturation, i.e. the establishment of maximum atomic bonding, any type of additional energy input will damage the bonding, decreasing the shear force. If the preheat temperature is not within the proper range, the interfacial saturation phenomenon does not exist. For a preload of 0.5 N and a welding time of 15 ms in thermosonic wire bonding of gold wire onto copper pads, a maximum shear force of about 0.33 N is found where the interfacial energy intensity equals 1.8×106 J m-2 for preheat temperatures of 150°C and 170°C. Moreover, the corresponding optimal ultrasonic power is about 110 units.

Development of wire wrapping technology for FBR fuel pin

International Nuclear Information System (INIS)

Nogami, Tetsuya; Seki, Nobuo; Sawayama, Takeo; Ishibashi, Takashi

1991-01-01

For the FBR fuel assembly, the spacer wire is adopted to maintain the space between fuel pins. The developments have been carried out to achieve automatically wire wrapping with high precision. Based on the fundamental technology developed through the mock-up test operation, Joyo 'MK-I', fuel pin fabrication was started using partially mechanized wire wrapping machine in 1973. In 1978, an automated wire wrapping machine for Joyo 'MK-II' was developed by the adoption of some improvements for the wire inserting system to end plug hole and the precision of wire pitch. On the bases of these experiences, fully automated wire wrapping machine for 'Monju' fuel pin was installed at Plutonium Fuel Production Facility (PFPF) in 1987. (author)

Accuracy and efficiency of full-arch digitalization and 3D printing: A comparison between desktop model scanners, an intraoral scanner, a CBCT model scan, and stereolithographic 3D printing.

Science.gov (United States)

Wesemann, Christian; Muallah, Jonas; Mah, James; Bumann, Axel

2017-01-01

The primary objective of this study was to compare the accuracy and time efficiency of an indirect and direct digitalization workflow with that of a three-dimensional (3D) printer in order to identify the most suitable method for orthodontic use. A master model was measured with a coordinate measuring instrument. The distances measured were the intercanine width, the intermolar width, and the dental arch length. Sixty-four scans were taken with each of the desktop scanners R900 and R700 (3Shape), the intraoral scanner TRIOS Color Pod (3Shape), and the Promax 3D Mid cone beam computed tomography (CBCT) unit (Planmeca). All scans were measured with measuring software. One scan was selected and printed 37 times on the D35 stereolithographic 3D printer (Innovation MediTech). The printed models were measured again using the coordinate measuring instrument. The most accurate results were obtained by the R900. The R700 and the TRIOS intraoral scanner showed comparable results. CBCT-3D-rendering with the Promax 3D Mid CBCT unit revealed significantly higher accuracy with regard to dental casts than dental impressions. 3D printing offered a significantly higher level of deviation than digitalization with desktop scanners or an intraoral scanner. The chairside time required for digital impressions was 27% longer than for conventional impressions. Conventional impressions, model casting, and optional digitization with desktop scanners remains the recommended workflow process. For orthodontic demands, intraoral scanners are a useful alternative for full-arch scans. For prosthodontic use, the scanning scope should be less than one quadrant and three additional teeth.

Evolution of the two-phase flow in a vertical tube-decomposition of gas fraction profiles according to bubble size classes using wire-mesh sensors

Energy Technology Data Exchange (ETDEWEB)

Prasser, H.M.; Krepper, E.; Lucas, D. [Forschungszentrum Rossendorf e.V., Dresden (Germany)

2002-01-01

The wire-mesh sensor developed by the Forschungszentrum Rossendorf produces sequences of instantaneous gas fraction distributions in a cross section with a time resolution of 1200 frames per second and a spatial resolution of about 2-3 mm. At moderate flow velocities (up to 1-2 m.s{sup -1}), bubble size distributions can be obtained, since each individual bubble is mapped in several successive distributions. The method was used to study the evolution of the bubble size distribution in a vertical two-phase flow. For this purpose, the sensor was placed downstream of an air injector, the distance between air injection and sensor was varied. The bubble identification algorithm allows to select bubbles of a given range of the effective diameter and to calculate partial gas fraction profiles for this diameter range. In this way, the different behaviour of small and large bubbles in respect to the action of the lift force was observed in a mixture of small and large bubbles. (authors)

Technical innovation: Wire guided ductography

International Nuclear Information System (INIS)

Aslam, Muhammad Ovais; Ramadan, Salwa; Al-Adwani, Muneera

2012-01-01

To introduce an easy and improved technique for performing ductography using inexpensive easily available intravenous cannula. Guide wire: Prolene/Surgipro 3-0 (Polypropylene mono filament non-absorbable surgical suture). A plastic 26 G intravenous cannula. Disposable syringe 2 ml. Non-ionic contrast (low density like Omnipaque 240 mg I/I). The guide wire (Prolene 3-0) is introduced into the orifice of the duct heaving discharge and 26 G intravenous plastic cannula is then passed over the guide wire. The cannula is advanced in the duct over guide wire by spinning around it. When the cannula is in place the guide wire is removed. Any air bubbles present in the hub of the cannula can be displaced by filling the hub from bottom upwards with needle attached to contrast filled syringe. 0.2–0.4 ml non-ionic contrast is gently injected. Injection is stopped if the patient has pain or burning. Magnified cranio-caudal view is obtained with cannula tapped in place and gentle compression is applied with the patient sitting. If duct filling is satisfactory a 90* lateral view is obtained. A successful adaptation of the technique for performing ductography is presented. The materials required for the technique are easily available in most radiology departments and are inexpensive, thus making the procedure comfortable for the patient and radiologist with considerable cost effectiveness.

Detector Position Estimation for PET Scanners.

Science.gov (United States)

Pierce, Larry; Miyaoka, Robert; Lewellen, Tom; Alessio, Adam; Kinahan, Paul

2012-06-11

Physical positioning of scintillation crystal detector blocks in Positron Emission Tomography (PET) scanners is not always exact. We test a proof of concept methodology for the determination of the six degrees of freedom for detector block positioning errors by utilizing a rotating point source over stepped axial intervals. To test our method, we created computer simulations of seven Micro Crystal Element Scanner (MiCES) PET systems with randomized positioning errors. The computer simulations show that our positioning algorithm can estimate the positions of the block detectors to an average of one-seventh of the crystal pitch tangentially, and one-third of the crystal pitch axially. Virtual acquisitions of a point source grid and a distributed phantom show that our algorithm improves both the quantitative and qualitative accuracy of the reconstructed objects. We believe this estimation algorithm is a practical and accurate method for determining the spatial positions of scintillation detector blocks.

Detector position estimation for PET scanners

International Nuclear Information System (INIS)

Pierce, Larry; Miyaoka, Robert; Lewellen, Tom; Alessio, Adam; Kinahan, Paul

2012-01-01

Physical positioning of scintillation crystal detector blocks in Positron Emission Tomography (PET) scanners is not always exact. We test a proof of concept methodology for the determination of the six degrees of freedom for detector block positioning errors by utilizing a rotating point source over stepped axial intervals. To test our method, we created computer simulations of seven Micro Crystal Element Scanner (MiCES) PET systems with randomized positioning errors. The computer simulations show that our positioning algorithm can estimate the positions of the block detectors to an average of one-seventh of the crystal pitch tangentially, and one-third of the crystal pitch axially. Virtual acquisitions of a point source grid and a distributed phantom show that our algorithm improves both the quantitative and qualitative accuracy of the reconstructed objects. We believe this estimation algorithm is a practical and accurate method for determining the spatial positions of scintillation detector blocks.

AN AUTOMATIC PROCEDURE FOR COMBINING DIGITAL IMAGES AND LASER SCANNER DATA

Directory of Open Access Journals (Sweden)

W. Moussa

2012-07-01

Full Text Available Besides improving both the geometry and the visual quality of the model, the integration of close-range photogrammetry and terrestrial laser scanning techniques directs at filling gaps in laser scanner point clouds to avoid modeling errors, reconstructing more details in higher resolution and recovering simple structures with less geometric details. Thus, within this paper a flexible approach for the automatic combination of digital images and laser scanner data is presented. Our approach comprises two methods for data fusion. The first method starts by a marker-free registration of digital images based on a point-based environment model (PEM of a scene which stores the 3D laser scanner point clouds associated with intensity and RGB values. The PEM allows the extraction of accurate control information for the direct computation of absolute camera orientations with redundant information by means of accurate space resection methods. In order to use the computed relations between the digital images and the laser scanner data, an extended Helmert (seven-parameter transformation is introduced and its parameters are estimated. Precedent to that, in the second method, the local relative orientation parameters of the camera images are calculated by means of an optimized Structure and Motion (SaM reconstruction method. Then, using the determined transformation parameters results in having absolute oriented images in relation to the laser scanner data. With the resulting absolute orientations we have employed robust dense image reconstruction algorithms to create oriented dense image point clouds, which are automatically combined with the laser scanner data to form a complete detailed representation of a scene. Examples of different data sets are shown and experimental results demonstrate the effectiveness of the presented procedures.

Upper limits of the photon fluence rate on CT detectors: Case study on a commercial scanner

Energy Technology Data Exchange (ETDEWEB)

Persson, Mats, E-mail: mats.persson@mi.physics.kth.se; Bornefalk, Hans; Danielsson, Mats [Department of Physics, Royal Institute of Technology, Stockholm SE-10691 (Sweden); Bujila, Robert; Nowik, Patrik; Andersson, Henrik [Unit of X-ray Physics, Section of Imaging Physics Solna, Department of Medical Physics, Karolinska University Hospital, Stockholm SE-17176 (Sweden); Kull, Love [Medical Radiation Physics, Sunderby Hospital, Luleå SE-97180 (Sweden); Andersson, Jonas [Department of Radiation Sciences, Radiation Physics, Umeå University, Umeå SE-90185 (Sweden)

2016-07-15

Purpose: The highest photon fluence rate that a computed tomography (CT) detector must be able to measure is an important parameter. The authors calculate the maximum transmitted fluence rate in a commercial CT scanner as a function of patient size for standard head, chest, and abdomen protocols. Methods: The authors scanned an anthropomorphic phantom (Kyoto Kagaku PBU-60) with the reference CT protocols provided by AAPM on a GE LightSpeed VCT scanner and noted the tube current applied with the tube current modulation (TCM) system. By rescaling this tube current using published measurements on the tube current modulation of a GE scanner [N. Keat, “CT scanner automatic exposure control systems,” MHRA Evaluation Report 05016, ImPACT, London, UK, 2005], the authors could estimate the tube current that these protocols would have resulted in for other patient sizes. An ECG gated chest protocol was also simulated. Using measured dose rate profiles along the bowtie filters, the authors simulated imaging of anonymized patient images with a range of sizes on a GE VCT scanner and calculated the maximum transmitted fluence rate. In addition, the 99th and the 95th percentiles of the transmitted fluence rate distribution behind the patient are calculated and the effect of omitting projection lines passing just below the skin line is investigated. Results: The highest transmitted fluence rates on the detector for the AAPM reference protocols with centered patients are found for head images and for intermediate-sized chest images, both with a maximum of 3.4 ⋅ 10{sup 8} mm{sup −2} s{sup −1}, at 949 mm distance from the source. Miscentering the head by 50 mm downward increases the maximum transmitted fluence rate to 5.7 ⋅ 10{sup 8} mm{sup −2} s{sup −1}. The ECG gated chest protocol gives fluence rates up to 2.3 ⋅ 10{sup 8} − 3.6 ⋅ 10{sup 8} mm{sup −2} s{sup −1} depending on miscentering. Conclusions: The fluence rate on a CT detector reaches 3 ⋅ 10{sup 8

Metallurgical investigation of wire breakage of tyre bead grade

Directory of Open Access Journals (Sweden)

Piyas Palit

2015-10-01

Full Text Available Tyre bead grade wire is used for tyre making application. The wire is used as reinforcement inside the polymer of tyre. The wire is available in different size/section such as 1.6–0.80 mm thin Cu coated wire. During tyre making operation at tyre manufacturer company, wire failed frequently. In this present study, different broken/defective wire samples were collected from wire mill for detailed investigation of the defect. The natures of the defects were localized and similar in nature. The fracture surface was of finger nail type. Crow feet like defects including button like surface abnormalities were also observed on the broken wire samples. The defect was studied at different directions under microscope. Different advanced metallographic techniques have been used for detail investigation. The analysis revealed that, white layer of surface martensite was formed and it caused the final breakage of wire. In this present study we have also discussed about the possible reason for the formation of such kind of surface martensite (hard-phase.

Ultra-High-Resolution Computed Tomography of the Lung: Image Quality of a Prototype Scanner

OpenAIRE

Kakinuma, Ryutaro; Moriyama, Noriyuki; Muramatsu, Yukio; Gomi, Shiho; Suzuki, Masahiro; Nagasawa, Hirobumi; Kusumoto, Masahiko; Aso, Tomohiko; Muramatsu, Yoshihisa; Tsuchida, Takaaki; Tsuta, Koji; Maeshima, Akiko Miyagi; Tochigi, Naobumi; Watanabe, Shun-ichi; Sugihara, Naoki

2015-01-01

Purpose: The image noise and image quality of a prototype ultra-high-resolution computed tomography (U-HRCT) scanner was evaluated and compared with those of conventional high-resolution CT (C-HRCT) scanners. Materials and Methods: This study was approved by the institutional review board. A U-HRCT scanner prototype with 0.25 mm × 4 rows and operating at 120 mAs was used. The C-HRCT images were obtained using a 0.5 mm × 16 or 0.5 mm × 64 detector-row CT scanner operating at 150 mAs. Images fr...

IEE wiring regulations explained and illustrated

CERN Document Server

Scaddan, Brian

2013-01-01

The IEE Wiring Regulations Explained and Illustrated, Second Edition discusses the recommendations of the IEE Regulations for the Electrical Equipment of Buildings for the safe selection or erection of wiring installations. The book emphasizes earthing, bonding, protection, and circuit design of electrical wirings. The text reviews the fundamental requirements for safety, earthing systems, the earth fault loop impedance, and supplementary bonding. The book also describes the different types of protection, such as protection against mechanical damage, overcurrent, under voltage (which prevents

Radiation safety concerns and diagnostic reference levels for computed tomography scanners in Tamil Nadu

International Nuclear Information System (INIS)

Livingstone, Roshan S.; Dinakaran, Paul M.

2011-01-01

Radiation safety in computed tomography (CT) scanners is of concern due its widespread use in the field of radiological imaging. This study intends to evaluate radiation doses imparted to patients undergoing thorax, abdomen and pelvic CT examinations and formulate regional diagnostic reference levels (DRL) in Tamil Nadu, South India. In-site CT dose measurement was performed in 127 CT scanners in Tamil Nadu for a period of 2 years as a part of the Atomic Energy Regulatory Board (AERB)-funded project. Out of the 127 CT scanners,13 were conventional; 53 single-slice helical scanners (SSHS); 44 multislice CT (MSCT) scanners; and 17 refurbished scanners. CT dose index (CTDI) was measured using a 32-cm polymethyl methacrylate (PMMA)-body phantom in each CT scanner. Dose length product (DLP) for different anatomical regions was generated using CTDI values. The regional DRLs for thorax, abdomen and pelvis examinations were 557, 521 and 294 mGy cm, respectively. The mean effective dose was estimated using the DLP values and was found to be 8.04, 6.69 and 4.79 mSv for thorax, abdomen and pelvic CT examinations, respectively. The establishment of DRLs in this study is the first step towards optimization of CT doses in the Indian context. (author)

Wiring Damage Analyses for STS OV-103

Science.gov (United States)

Thomas, Walter, III

2006-01-01

This study investigated the Shuttle Program s belief that Space Transportation System (STS) wiring damage occurrences are random, that is, a constant occurrence rate. Using Problem Reporting and Corrective Action (PRACA)-derived data for STS Space Shuttle OV-103, wiring damage was observed to increase over the vehicle s life. Causal factors could include wiring physical deterioration, maintenance and inspection induced damage, and inspection process changes resulting in more damage events being reported. Induced damage effects cannot be resolved with existent data. Growth analysis (using Crow-AMSAA, or CA) resolved maintenance/inspection effects (e.g., heightened awareness) on all wire damages and indicated an overall increase since Challenger Return-to-Flight (RTF). An increasing failure or occurrence rate per flight cycle was seen for each wire damage mode; these (individual) rates were not affected by inspection process effects, within statistical error.

Investigation of ball bond integrity for 0.8 mil (20 microns) diameter gold bonding wire on low k die in wire bonding technology

Science.gov (United States)

Kudtarkar, Santosh Anil

Microelectronics technology has been undergoing continuous scaling to accommodate customer driven demand for smaller, faster and cheaper products. This demand has been satisfied by using novel materials, design techniques and processes. This results in challenges for the chip connection technology and also the package technology. The focus of this research endeavor was restricted to wire bond interconnect technology using gold bonding wires. Wire bond technology is often regarded as a simple first level interconnection technique. In reality, however, this is a complex process that requires a thorough understanding of the interactions between the design, material and process variables, and their impact on the reliability of the bond formed during this process. This research endeavor primarily focused on low diameter, 0.8 mil thick (20 mum) diameter gold bonding wire. Within the scope of this research, the integrity of the ball bond formed by 1.0 mil (25 mum) and 0.8 mil (20 mum) diameter wires was compared. This was followed by the evaluation of bonds formed on bond pads having doped SiO2 (low k) as underlying structures. In addition, the effect of varying the percentage of the wire dopant, palladium and bonding process parameters (bonding force, bond time, ultrasonic energy) for 0.8 mil (20 mum) bonding wire was also evaluated. Finally, a degradation empirical model was developed to understand the decrease in the wire strength. This research effort helped to develop a fundamental understanding of the various factors affecting the reliability of a ball bond from a design (low diameter bonding wire), material (low k and bonding wire dopants), and process (wire bonding process parameters) perspective for a first level interconnection technique, namely wire bonding. The significance of this research endeavor was the systematic investigation of the ball bonds formed using 0.8 mil (20 microm) gold bonding wire within the wire bonding arena. This research addressed low k

Indirect identification and compensation of lateral scanner resonances in atomic force microscopes

International Nuclear Information System (INIS)

Burns, D J; Youcef-Toumi, K; Fantner, G E

2011-01-01

Improving the imaging speed of atomic force microscopy (AFM) requires accurate nanopositioning at high speeds. However, high speed operation excites resonances in the AFM's mechanical scanner that can distort the image, and therefore typical users of commercial AFMs elect to operate microscopes at speeds below which scanner resonances are observed. Although traditional robust feedforward controllers and input shaping have proven effective at minimizing the influence of scanner distortions, the lack of direct measurement and use of model-based controllers have required disassembling the microscope to access lateral scanner motion with external sensors in order to perform a full system identification experiment, which places excessive demands on routine microscope operators. Further, since the lightly damped instrument dynamics often change from experiment to experiment, model-based controllers designed from offline system identification experiments must trade off high speed performance for robustness to modeling errors. This work represents a new way to automatically characterize the lateral scanner dynamics without addition of lateral sensors, and shape the commanded input signals in such a way that disturbing dynamics are not excited. Scanner coupling between the lateral and out-of-plane directions is exploited and used to build a minimal model of the scanner that is also sufficient to describe the nature of the distorting resonances. This model informs the design of an online input shaper used to suppress spectral components of the high speed command signals. The method presented is distinct from alternative approaches in that neither an information-complete system identification experiment nor microscope modification are required. Because the system identification is performed online immediately before imaging, no tradeoff of performance is required. This approach has enabled an increase in the scan rates of unmodified commercial AFMs from 1-4 lines s -1 to over

Pretinning Nickel-Plated Wire Shields

Science.gov (United States)

Igawa, J. A.

1985-01-01

Nickel-plated copper shielding for wires pretinned for subsequent soldering with help of activated rosin flux. Shield cut at point 0.25 to 0.375 in. (6 to 10 mm) from cut end of outer jacket. Loosened end of shield straightened and pulled toward cut end. Insulation of inner wires kept intact during pretinning.

Inter-operator and inter-device agreement and reliability of the SEM Scanner.

Science.gov (United States)

Clendenin, Marta; Jaradeh, Kindah; Shamirian, Anasheh; Rhodes, Shannon L

2015-02-01

The SEM Scanner is a medical device designed for use by healthcare providers as part of pressure ulcer prevention programs. The objective of this study was to evaluate the inter-rater and inter-device agreement and reliability of the SEM Scanner. Thirty-one (31) volunteers free of pressure ulcers or broken skin at the sternum, sacrum, and heels were assessed with the SEM Scanner. Each of three operators utilized each of three devices to collect readings from four anatomical sites (sternum, sacrum, left and right heels) on each subject for a total of 108 readings per subject collected over approximately 30 min. For each combination of operator-device-anatomical site, three SEM readings were collected. Inter-operator and inter-device agreement and reliability were estimated. Over the course of this study, more than 3000 SEM Scanner readings were collected. Agreement between operators was good with mean differences ranging from -0.01 to 0.11. Inter-operator and inter-device reliability exceeded 0.80 at all anatomical sites assessed. The results of this study demonstrate the high reliability and good agreement of the SEM Scanner across different operators and different devices. Given the limitations of current methods to prevent and detect pressure ulcers, the SEM Scanner shows promise as an objective, reliable tool for assessing the presence or absence of pressure-induced tissue damage such as pressure ulcers. Copyright © 2015 Bruin Biometrics, LLC. Published by Elsevier Ltd.. All rights reserved.

A double-bent planar leaf flexure guide for a nano-scanner: experimental report

International Nuclear Information System (INIS)

Jeon, Jeong-Woo; Kim, Jong-Moon; Lee, Young-Hyoung; Lee, Dong-Yeon

2014-01-01

We describe an experimental study on the double-bent leaf flexure-guided nano-scanner introduced in a previous paper [J. Korean Phy. Soc. 57, 1581 (2010)]. The optimally-designed nanoscanner was fabricated. Its performances were verified using a finite element analysis (FEA). The nano-scanner is actuated by a voice coil motor. Its characteristics were measured with a laser interferometer. The first resonant frequency is calculated as 17.1 Hz. The performances of the nano-scanner, including sine tracking capability, a multi-step response, and range of travel check were evaluated using various experimental procedures. Test results reveal that the scanner traveled over a 4.0 mm range and had good nano-precision (4 nm).

A sweep plate emittance scanner for high-power CW ion beams

International Nuclear Information System (INIS)

Debiak, T.W.; Ng, Y.; Sredniawski, J.; Stasi, W.

1996-01-01

Sweep plate scanners are preferred for emittance measurement due to their versatility, simplicity, and precision. At the Advanced Technology and Development Center of Northrop Grumman, we have routinely used these devices for characterization of injector beams with less than 20 W/cm 2 average power density. To characterize higher power beams, like those required for production of tritium or for radioactive waste transmutation, the scanner pod and data collection algorithm must be redesigned due to the possibility of melting the scanner's protective front face or distorting the precision entrance knife edges. Among the methods we have used to mitigate these effects, one consists of drastically reducing the amount of time required for data collection. In this method, the emittance scanner pod traverses the beam in two passes, each requiring less than 0.5 second. In the first pass, the phase space limits of the beam are determined. In the second pass, data is collected primarily within the phase space region limits determined in the first pass. In this way, enough points are collected to assure that the precision of the measurement is high, even though the data collection time for each scan is less than 0.5 second. This paper will describe the layout of the scanner components, the data collection electronics and algorithm, and the data analysis. (author)

Supplemental Analysis Survey of C&P Telephone Inside Wiring.