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.

Wire Scanner Beam Profile Measurements for the LANSCE Facility

Energy Technology Data Exchange (ETDEWEB)

Gilpatrick, John D. [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Martinez, Derwin [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

2012-05-15

The Los Alamos Neutron Science Center (LANSCE) is replacing beam profile measurement systems, commonly known as Wire Scanners (WS). Using the principal of secondary electron emission, the WS measurement system moves a wire or fiber across an impinging particle beam, sampling a projected transverse-beam distribution. Because existing WS actuators and electronic components are either no longer manufactured or home-built with antiquated parts, a new WS beam profile measurement is being designed, fabricated, and tested. The goals for these new WS's include using off-the-shelf components while eliminating antiquated components, providing quick operation while allowing for easy maintainability, and tolerating external radioactivation. The WS measurement system consists of beam line actuators, a cable plant, an electronics processor chassis, and software located both in the electronics chassis (National Instruments LabVIEW) and in the Central Control Room (EPICS-based client software). This WS measurement system will measure Hand H{sup +} LANSCE-facility beams and will also measure less common beams. This paper describes these WS measurement systems.

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.

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 ...

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.)

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

Wire breakage in SLC wire profile monitors

International Nuclear Information System (INIS)

Field, C.; McCormick, D.; Raimondi, P.; Ross, M.

1998-05-01

Wire scanning beam profile monitors are used at the Stanford Linear Collider (SLC) for emittance preservation control and beam optics optimization. Twenty such scanners have proven most useful for this purpose and have performed a total of 1.5 million scans in the 4 to 6 years since their installation. Most of the essential scanners are equipped with 20 to 40 microm tungsten wires. SLC bunch intensities and sizes often exceed 2 x 10 7 particles/microm 2 (3C/m 2 ). The authors believe that this has caused a number of tungsten wire failures that appear at the ends of the wire, near the wire support points, after a few hundred scans are accumulated. Carbon fibers, also widely used at SLAC, have been substituted in several scanners and have performed well. In this paper, the authors present theories for the wire failure mechanism and techniques learned in reducing the failures

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; 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.

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.

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.

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...

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...

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.

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)

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.

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...

2-D Low Energy Electron Beam Profile Measurement Based on Computer Tomography Algorithm with Multi-Wire Scanner

CERN Document Server

Yu, Nengjie; Li Qing Feng; Tang, Chuan-Xiang; Zheng, Shuxin

2005-01-01

A new method for low energy electron beam profile measurement is advanced, which presents a full 2-D beam profile distribution other than the traditional 2-D beam profile distribution given by 1-D vertical and horizontal beam profiles. The method is based on the CT (Computer Tomography) algorithm. Multi-sets of data about the 1-D beam profile projections are attained by rotating the multi-wire scanner. Then a 2-D beam profile is reconstructed from these projections with CT algorithm. The principle of this method is presented. The simulation and the experiment results are compared and analyzed in detail.

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)

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.

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.

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.

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...

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

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.

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)

Wire-rope emplacement of diagnostics systems

International Nuclear Information System (INIS)

Burden, W.L.

1982-01-01

The study reported here was initiated to determine if, with the Cable Downhole System (CDS) currently under development, there is an advantage to using continuous wire rope to lower the emplacement package to the bottom of the hole. A baseline design using two wire ropes as well as several alternatives are discussed in this report. It was concluded that the advantages of the wire-rope emplacement system do not justify the cost of converting to such a system, especially for LLNL's maximum emplacement package weights

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)

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.

Beam Position and Phase Monitor - Wire Mapping System

International Nuclear Information System (INIS)

Watkins, Heath A.; Shurter, Robert B.; Gilpatrick, John D.; Kutac, Vincent G.; Martinez, Derwin

2012-01-01

The Los Alamos Neutron Science Center (LANSCE) deploys many cylindrical beam position and phase monitors (BPPM) throughout the linac to measure the beam central position, phase and bunched-beam current. Each monitor is calibrated and qualified prior to installation to insure it meets LANSCE requirements. The BPPM wire mapping system is used to map the BPPM electrode offset, sensitivity and higher order coefficients. This system uses a three-axis motion table to position the wire antenna structure within the cavity, simulating the beam excitation of a BPPM at a fundamental frequency of 201.25 MHz. RF signal strength is measured and recorded for the four electrodes as the antenna position is updated. An effort is underway to extend the systems service to the LANSCE facility by replacing obsolete electronic hardware and taking advantage of software enhancements. This paper describes the upgraded wire positioning system's new hardware and software capabilities including its revised antenna structure, motion control interface, RF measurement equipment and Labview software upgrades. The main purpose of the wire mapping system at LANSCE is to characterize the amplitude response versus beam central position of BPPMs before they are installed in the beam line. The wire mapping system is able to simulate a beam using a thin wire and measure the signal response as the wire position is varied within the BPPM aperture.

Modern trends of aircraft fly-by-wire systems

Directory of Open Access Journals (Sweden)

С. С. Юцкевич

2013-07-01

Full Text Available Specifics of civil aviation modern transport aircraft fly-by-wire control systems are described. A comparison of the systems-level hardware and software, expressed through modes of guidance, provision of aircraft Airbus A-320, Boeing B-777, Tupolev Tu-214, Sukhoi Superjet SSJ-100 are carried out. The possibility of transition from mechanical control wiring to control through fly-by-wire system in the backup channel is shown.

Interchip link system using an optical wiring method.

Science.gov (United States)

Cho, In-Kui; Ryu, Jin-Hwa; Jeong, Myung-Yung

2008-08-15

A chip-scale optical link system is presented with a transmitter/receiver and optical wire link. The interchip link system consists of a metal optical bench, a printed circuit board module, a driver/receiver integrated circuit, a vertical cavity surface-emitting laser/photodiode array, and an optical wire link composed of plastic optical fibers (POFs). We have developed a downsized POF and an optical wiring method that allows on-site installation with a simple annealing as optical wiring technologies for achieving high-density optical interchip interconnection within such devices. Successful data transfer measurements are presented.

Model-Based Testability Assessment and Directed Troubleshooting of Shuttle Wiring Systems

Science.gov (United States)

Deb, Somnath; Domagala, Chuck; Shrestha, Roshan; Malepati, Venkatesh; Cavanaugh, Kevin; Patterson-Hine, Ann; Sanderfer, Dwight; Cockrell, Jim; Norvig, Peter (Technical Monitor)

2000-01-01

We have recently completed a pilot study on the Space shuttle wiring system commissioned by the Wiring Integrity Research (WIRe) team at NASA Ames Research Center, As the space shuttle ages, it is experiencing wiring degradation problems including arcing, chaffing insulation breakdown and broken conductors. A systematic and comprehensive test process is required to thoroughly test and quality assure (QA) the wiring systems. The NASA WIRe team recognized the value of a formal model based analysis for risk-assessment and fault coverage analysis. However. wiring systems are complex and involve over 50,000 wire segments. Therefore, NASA commissioned this pilot study with Qualtech Systems. Inc. (QSI) to explore means of automatically extracting high fidelity multi-signal models from wiring information database for use with QSI's Testability Engineering and Maintenance System (TEAMS) tool.

Wire system aging assessment and condition monitoring (WASCO)

International Nuclear Information System (INIS)

Fantoni, P.F.

2007-04-01

Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. Condition Monitoring (CM) of installed wire systems is an important part of any aging program, both during the first 40 years of the qualified life and even more in anticipation of the license renewal for a nuclear power plant. This report contains some test results of a method for wire system condition monitoring, developed at the Halden Reactor Project, called LIRA (LIne Resonance Analysis), which can be used on-line to detect any local or global changes in the cable electrical parameters as a consequence of insulation faults or degradation. (au)

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.

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

Upgrading PABX Infra System and Wiring for Communication System in Selected Block

International Nuclear Information System (INIS)

Sahirudden Mohd Nor; Khairiah Yazid; Lojius Lombigit; Zainuddin Jaafar; Abd Aziz Mhd Ramli

2015-01-01

Infra phone system in Nuclear Malaysia has been operating since its inception. Infra phone system is used to enable the communications process run smoothly. There are two mains phone system which are mannex analog system in the main complex and MD110 systems in Dengkil complex. This system was responsibilities and monitored by Automation and Instrumentation Center, Technical Support Division. Infra phone system and its wiring in the main complexes have not been upgraded and there are a lot of faulty wiring. This phone system requires new wiring system with the addition of new buildings in Nuclear Malaysia. The system also requires new parts to ensure smooth communication system in future. (author)

NASA/BAE SYSTEMS SpaceWire Effort

Science.gov (United States)

Rakow, Glenn Parker; Schnurr, Richard G.; Kapcio, Paul

2003-01-01

This paper discusses the state of the NASA and BAE SYSTEMS developments of SpaceWire. NASA has developed intellectual property that implements SpaceWire in Register Transfer Level (RTL) VHDL for a SpaceWire link and router. This design has been extensively verified using directed tests from the SpaceWire Standard and design specification, as well as being randomly tested to flush out hard to find bugs in the code. The high level features of the design will be discussed, including the support for multiple time code masters, which will be useful for the James Webb Space Telescope electrical architecture. This design is now ready to be targeted to FPGA's and ASICs. Target utilization and performance information will be presented for Spaceflight worthy FPGA's and a discussion of the ASIC implementations will be addressed. In particular, the BAE SYSTEMS ASIC will be highlighted which will be implemented on their .25micron rad-hard line. The chip will implement a 4-port router with the ability to tie chips together to make larger routers without external glue logic. This part will have integrated LVDS drivers/receivers, include a PLL and include skew control logic. It will be targeted to run at greater than 300 MHz and include the implementation for the proposed SpaceWire transport layer. The need to provide a reliable transport mechanism for SpaceWire has been identified by both NASA And ESA, who are attempting to define a transport layer standard that utilizes a low overhead, low latency connection oriented approach that works end-to-end. This layer needs to be implemented in hardware to prevent bottlenecks.

An automatic tension measurement system of MWPC wires

International Nuclear Information System (INIS)

D'Antone, I.; Lolli, M.; Torromeo, G.

1992-01-01

An electronic system is presented for automatic mechanical tension measurement to test wire chambers. The developed system works in the tension range from 50 g to 300 g; this large working range is obtained by using a microcontroller that performs a digital control on the bridge of an oscillator containing the wire of which the tension has to be measured. The microcontroller automatically brings the system towards the oscillation condition and subsequently, measuring the frequency, it evaluates, displays and sends to a host computer the value of the mechanical tension of the wires. The system is precise and allows fast measurements. A description of the hardware and software design is given. (orig.)

A Prototype Wire Position Monitoring System

International Nuclear Information System (INIS)

Wang, Wei

2010-01-01

The Wire Position Monitoring System (WPM) will track changes in the transverse position of LCLS Beam Position Monitors (BPMs) to 1(micro)m over several weeks. This position information will be used between applications of beam based alignment to correct for changes in component alignment. The WPM system has several requirements. The sensor range must be large enough so that precision sensor positioning is not required. The resolution needs to be small enough so that the signal can be used to monitor motion to 1(micro)m. The system must be stable enough so that system drift does not mimic motion of the component being monitored. The WPM sensor assembly consists of two parts, the magnetic sensor and an integrated lock-in amplifier. The magnetic sensor picks up a signal from the alternating current in a stretched wire. The voltage v induced in the sensor is proportional to the wire displacement from the center of the sensor. The integrated lock-in amplifier provides a DC output whose magnitude is proportional to the AC signal from the magnetic sensor. The DC output is either read on a digital voltmeter or digitized locally and communicated over a computer interface.

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...

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.

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

Wire system aging assessment and condition monitoring (WASCO)

International Nuclear Information System (INIS)

Fantoni, P.F.; Nordlund, A.

2006-04-01

Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. Condition Monitoring (CM) of installed wire systems is an important part of any aging program, both during the first 40 years of the qualified life and even more in anticipation of the license renewal for a nuclear power plant. This report describes a method for wire system condition monitoring, developed at the Halden Reactor Project, which is based on Frequency Domain Reflectometry. This method resulted in the development of a system called LIRA (LIne Resonance Analysis), which can be used on-line to detect any local or global changes in the cable electrical parameters as a consequence of insulation faults or degradation. LIRA is composed of a signal generator, a signal analyser and a simulator that can be used to simulate several failure/degradation scenarios and assess the accuracy and sensitivity of the LIRA system. Chapter 5 of this report describes an complementary approach based on positron measurement techniques, used widely in defect physics due to the high sensitivity to micro defects, in particular open volume defects. This report describes in details these methodologies, the results of field experiments and the proposed future work. (au)

Wire system aging assessment and condition monitoring (WASCO)

Energy Technology Data Exchange (ETDEWEB)

Fantoni, P.F. [Institutt for energiteknikk (Norway); Nordlund, A. [Chalmers Univ. of Technology (Sweden)

2006-04-15

Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. Condition Monitoring (CM) of installed wire systems is an important part of any aging program, both during the first 40 years of the qualified life and even more in anticipation of the license renewal for a nuclear power plant. This report describes a method for wire system condition monitoring, developed at the Halden Reactor Project, which is based on Frequency Domain Reflectometry. This method resulted in the development of a system called LIRA (LIne Resonance Analysis), which can be used on-line to detect any local or global changes in the cable electrical parameters as a consequence of insulation faults or degradation. LIRA is composed of a signal generator, a signal analyser and a simulator that can be used to simulate several failure/degradation scenarios and assess the accuracy and sensitivity of the LIRA system. Chapter 5 of this report describes an complementary approach based on positron measurement techniques, used widely in defect physics due to the high sensitivity to micro defects, in particular open volume defects. This report describes in details these methodologies, the results of field experiments and the proposed future work. (au)

Strain sensing systems tailored for tensile measurement of fragile wires

Science.gov (United States)

Nyilas, Arman

2005-12-01

Fundamental stress versus strain measurements were completed on superconducting Nb3Sn wires within the framework of IEC/TC90 and VAMAS/TWA16. A key task was the assessment of sensing systems regarding resolution, accuracy, and precision when measuring Young's modulus. Prior to actual Nb3Sn wire measurements metallic wires, consisting of copper and stainless steel having diameters similar to the Nb3Sn wire, were extensively investigated with respect to their elastic line properties using different types of extensometers. After these calibration tests Nb3Sn wire measurements of different companies resulted in several important facts with respect to total size and weight of the used extensometers. The size could be correlated to the initial stage of stress versus strain behaviour. In fact, the effect of wire curls resulting from the production line had a profound effect on Young's modulus measurements. Within this context, the possibility of determining Young's modulus from unloading compliance lines in the plastic regime of the stress-strain curve was considered. The data obtained using this test methodology were discussed under consideration of the composite nature of Nb3Sn wire. In addition, a non-contacting sensing system based on a double-beam laser extensometer was used to investigate the potential of this new sensing system.

Strain sensing systems tailored for tensile measurement of fragile wires

International Nuclear Information System (INIS)

Nyilas, Arman

2005-01-01

Fundamental stress versus strain measurements were completed on superconducting Nb 3 Sn wires within the framework of IEC/TC90 and VAMAS/TWA16. A key task was the assessment of sensing systems regarding resolution, accuracy, and precision when measuring Young's modulus. Prior to actual Nb 3 Sn wire measurements metallic wires, consisting of copper and stainless steel having diameters similar to the Nb 3 Sn wire, were extensively investigated with respect to their elastic line properties using different types of extensometers. After these calibration tests Nb 3 Sn wire measurements of different companies resulted in several important facts with respect to total size and weight of the used extensometers. The size could be correlated to the initial stage of stress versus strain behaviour. In fact, the effect of wire curls resulting from the production line had a profound effect on Young's modulus measurements. Within this context, the possibility of determining Young's modulus from unloading compliance lines in the plastic regime of the stress-strain curve was considered. The data obtained using this test methodology were discussed under consideration of the composite nature of Nb 3 Sn wire. In addition, a non-contacting sensing system based on a double-beam laser extensometer was used to investigate the potential of this new sensing system

Operational environments for electrical power wiring on NASA space systems

Science.gov (United States)

Stavnes, Mark W.; Hammoud, Ahmad N.; Bercaw, Robert W.

1994-01-01

Electrical wiring systems are used extensively on NASA space systems for power management and distribution, control and command, and data transmission. The reliability of these systems when exposed to the harsh environments of space is very critical to mission success and crew safety. Failures have been reported both on the ground and in flight due to arc tracking in the wiring harnesses, made possible by insulation degradation. This report was written as part of a NASA Office of Safety and Mission Assurance (Code Q) program to identify and characterize wiring systems in terms of their potential use in aerospace vehicles. The goal of the program is to provide the information and guidance needed to develop and qualify reliable, safe, lightweight wiring systems, which are resistant to arc tracking and suitable for use in space power applications. This report identifies the environments in which NASA spacecraft will operate, and determines the specific NASA testing requirements. A summary of related test programs is also given in this report. This data will be valuable to spacecraft designers in determining the best wiring constructions for the various NASA applications.

Benchmarking Advanced Control Algorithms for a Laser Scanner System

DEFF Research Database (Denmark)

Stoustrup, Jakob; Ordys, A.W.; Smillie, I.

1996-01-01

The paper describes tests performed on the laser scanner system toassess feasibility of modern control techniques in achieving a requiredperformance in the trajectory following problem. The two methods tested areQTR H-infinity and Predictive Control. The results are ilustated ona simulation example....

New Structure Design and Simulation of Brake by Wire System Based on Giant-magnetostrictive Material

Directory of Open Access Journals (Sweden)

Changbao CHU

2014-04-01

Full Text Available Existing electronic mechanical brake by wire system has several disadvantages. For instance, system actuators are complex, response speed slower, larger vibration noise, etc. This paper discusses a new type brake by wire system based on giant-magnetostrictive material. The new type brake by wire system model was set up under Matlab/Simulink software environment. PID control method was used to control the brake by wire system. Simulation results shows that the new type brake by wire system achieves better braking performance compared with hydraulic braking system. This work provides a new idea for researching automobile brake by wire system.

Validity and Repeatability of the Sizestream 3D Scanner and Poikos Modeling System

NARCIS (Netherlands)

Vonk, T.E.; Daanen, H.A.M.

2015-01-01

Three-dimensional (3D) body scanning becomes increasingly important in the medical, ergonomical and apparel industry. The SizeStream 3D body scanner is a 3D body scanner in the shape of a fitting room that can generate a 3D copy of the human body in a few seconds. The Poikos modeling system

Magnetization reversal modes in fourfold Co nano-wire systems

International Nuclear Information System (INIS)

Blachowicz, T; Ehrmann, A

2015-01-01

Magnetic nano-wire systems are, as well as other patterned magnetic structures, of special interest for novel applications, such as magnetic storage media. In these systems, the coupling between neighbouring magnetic units is most important for the magnetization reversal process of the complete system, leading to a variety of magnetization reversal mechanisms. This article examines the influence of the magnetic material on hysteresis loop shape, coercive field, and magnetization reversal modes. While iron nano-wire systems exhibit flat or one-step hysteresis loops, systems consisting of cobalt nano-wires show hysteresis loops with several longitudinal steps and transverse peaks, correlated to a rich spectrum of magnetization reversal mechanisms. We show that changing the material parameters while the system geometry stays identical can lead to completely different hysteresis loops and reversal modes. Thus, especially for finding magnetic nano-systems which can be used as quaternary or even higher-order storage devices, it is rational to test several materials for the planned systems. Apparently, new materials may lead to novel and unexpected behaviour - and can thus result in novel functionalities. (paper)

Magnetization reversal modes in fourfold Co nano-wire systems

Science.gov (United States)

Blachowicz, T.; Ehrmann, A.

2015-09-01

Magnetic nano-wire systems are, as well as other patterned magnetic structures, of special interest for novel applications, such as magnetic storage media. In these systems, the coupling between neighbouring magnetic units is most important for the magnetization reversal process of the complete system, leading to a variety of magnetization reversal mechanisms. This article examines the influence of the magnetic material on hysteresis loop shape, coercive field, and magnetization reversal modes. While iron nano-wire systems exhibit flat or one-step hysteresis loops, systems consisting of cobalt nano-wires show hysteresis loops with several longitudinal steps and transverse peaks, correlated to a rich spectrum of magnetization reversal mechanisms. We show that changing the material parameters while the system geometry stays identical can lead to completely different hysteresis loops and reversal modes. Thus, especially for finding magnetic nano-systems which can be used as quaternary or even higher-order storage devices, it is rational to test several materials for the planned systems. Apparently, new materials may lead to novel and unexpected behaviour - and can thus result in novel functionalities.

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...

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

Design of a laser scanner for a digital mammography system.

Science.gov (United States)

Rowlands, J A; Taylor, J E

1996-05-01

We have developed a digital readout system for radiographic images using a scanning laser beam. In this system, electrostatic charge images on amorphous selenium (alpha-Se) plates are read out using photo-induced discharge (PID). We discuss the design requirements of a laser scanner for the PID system and describe its construction from commercially available components. The principles demonstrated can be adapted to a variety of digital imaging systems.

SU-E-P-11: Comparison of Image Quality and Radiation Dose Between Different Scanner System in Routine Abdomen CT

Energy Technology Data Exchange (ETDEWEB)

Liao, S; Wang, Y; Weng, H [Chiayi Chang Gung Memorial Hospital of The C.G.M.F, Puzi City, Chiayi County, Taiwan (China)

2015-06-15

Purpose To evaluate image quality and radiation dose of routine abdomen computed tomography exam with the automatic current modulation technique (ATCM) performed in two different brand 64-slice CT scanners in our site. Materials and Methods A retrospective review of routine abdomen CT exam performed with two scanners; scanner A and scanner B in our site. To calculate standard deviation of the portal hepatic level with a region of interest of 12.5 mm x 12.5mm represented to the image noise. The radiation dose was obtained from CT DICOM image information. Using Computed tomography dose index volume (CTDIv) to represented CT radiation dose. The patient data in this study were with normal weight (about 65–75 Kg). Results The standard deviation of Scanner A was smaller than scanner B, the scanner A might with better image quality than scanner B. On the other hand, the radiation dose of scanner A was higher than scanner B(about higher 50–60%) with ATCM. Both of them, the radiation dose was under diagnostic reference level. Conclusion The ATCM systems in modern CT scanners can contribute a significant reduction in radiation dose to the patient. But the reduction by ATCM systems from different CT scanner manufacturers has slightly variation. Whatever CT scanner we use, it is necessary to find the acceptable threshold of image quality with the minimum possible radiation exposure to the patient in agreement with the ALARA principle.

SU-E-P-11: Comparison of Image Quality and Radiation Dose Between Different Scanner System in Routine Abdomen CT

International Nuclear Information System (INIS)

Liao, S; Wang, Y; Weng, H

2015-01-01

Purpose To evaluate image quality and radiation dose of routine abdomen computed tomography exam with the automatic current modulation technique (ATCM) performed in two different brand 64-slice CT scanners in our site. Materials and Methods A retrospective review of routine abdomen CT exam performed with two scanners; scanner A and scanner B in our site. To calculate standard deviation of the portal hepatic level with a region of interest of 12.5 mm x 12.5mm represented to the image noise. The radiation dose was obtained from CT DICOM image information. Using Computed tomography dose index volume (CTDIv) to represented CT radiation dose. The patient data in this study were with normal weight (about 65–75 Kg). Results The standard deviation of Scanner A was smaller than scanner B, the scanner A might with better image quality than scanner B. On the other hand, the radiation dose of scanner A was higher than scanner B(about higher 50–60%) with ATCM. Both of them, the radiation dose was under diagnostic reference level. Conclusion The ATCM systems in modern CT scanners can contribute a significant reduction in radiation dose to the patient. But the reduction by ATCM systems from different CT scanner manufacturers has slightly variation. Whatever CT scanner we use, it is necessary to find the acceptable threshold of image quality with the minimum possible radiation exposure to the patient in agreement with the ALARA principle

Design of power cable grounding wire anti-theft monitoring system

Science.gov (United States)

An, Xisheng; Lu, Peng; Wei, Niansheng; Hong, Gang

2018-01-01

In order to prevent the serious consequences of the power grid failure caused by the power cable grounding wire theft, this paper presents a GPRS based power cable grounding wire anti-theft monitoring device system, which includes a camera module, a sensor module, a micro processing system module, and a data monitoring center module, a mobile terminal module. Our design utilize two kinds of methods for detecting and reporting comprehensive image, it can effectively solve the problem of power and cable grounding wire box theft problem, timely follow-up grounded cable theft events, prevent the occurrence of electric field of high voltage transmission line fault, improve the reliability of the safe operation of power grid.

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

The design of the CMOS wireless bar code scanner applying optical system based on ZigBee

Science.gov (United States)

Chen, Yuelin; Peng, Jian

2008-03-01

The traditional bar code scanner is influenced by the length of data line, but the farthest distance of the wireless bar code scanner of wireless communication is generally between 30m and 100m on the market. By rebuilding the traditional CCD optical bar code scanner, a CMOS code scanner is designed based on the ZigBee to meet the demands of market. The scan system consists of the CMOS image sensor and embedded chip S3C2401X, when the two dimensional bar code is read, the results show the inaccurate and wrong code bar, resulted from image defile, disturber, reads image condition badness, signal interference, unstable system voltage. So we put forward the method which uses the matrix evaluation and Read-Solomon arithmetic to solve them. In order to construct the whole wireless optics of bar code system and to ensure its ability of transmitting bar code image signals digitally with long distances, ZigBee is used to transmit data to the base station, and this module is designed based on image acquisition system, and at last the wireless transmitting/receiving CC2430 module circuit linking chart is established. And by transplanting the embedded RTOS system LINUX to the MCU, an applying wireless CMOS optics bar code scanner and multi-task system is constructed. Finally, performance of communication is tested by evaluation software Smart RF. In broad space, every ZIGBEE node can realize 50m transmission with high reliability. When adding more ZigBee nodes, the transmission distance can be several thousands of meters long.

Implementation of a versatile research data acquisition system using a commercially available medical ultrasound scanner

DEFF Research Database (Denmark)

Hemmsen, Martin Christian; Nikolov, Svetoslav Ivanov; Pedersen, Mads Møller

2012-01-01

to the clinic. The system consists of a standard PC equipped with a camera link and an ultrasound scanner equipped with a research interface. The ultrasound scanner is an easy-to-use imaging device that is capable of generating high-quality images. In addition to supporting the acquisition of multiple data...

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.

DTR, Taut Wire System: An alarm barrier with experience

International Nuclear Information System (INIS)

Kraft, A.J.

1986-01-01

The Taut Wire Fence Alarm System concept was developed and introduced more that fifteen years ago in Israel. A sudden expansion of the nations's border lines, the difficulty to monitor intrusions along those elongated lines and the need for timely as well as accurate armed response to an intrusion attempt dictated the need for an alarming barrier. Traditionally, protection of perimeters was accomplished by the installation of a fence or other type obstacles (man made or natural) and surveillance by manned patrols, fixed observation posts, and/or electronic devices. Defense planners recognized therefore the need for an alarming barrier. A concentrated effort by scientists solved the problem by developing the first Taut Wire Fence Alarm System in a configuration of an alarm barrier. The system was specified to have an extremely low false alarm rate (FAR/NAR), high probability of detection, the capability to follow various terrains, operability in a wide range of environmental conditions, a capability to delay an intruder, ease of installation by unskilled labor, and low maintenance requirements. The authors try here to explain the various constraints and considerations given during the design stages of the Taut Wire Alarm System so as to bring the present magnitude of users to a better understanding of the system's operation

A One Chip Hardened Solution for High Speed SpaceWire System Implementations. Session: Components

Science.gov (United States)

Marshall, Joseph R.; Berger, Richard W.; Rakow, Glenn P.

2007-01-01

An Application Specific Integrated Circuit (ASIC) that implements the SpaceWire protocol has been developed in a radiation hardened 0.25 micron CMOS technology. This effort began in March 2003 as a joint development between the NASA Goddard Space Flight Center (GSFC) and BAE Systems. The BAE Systems SpaceWire ASIC is comprised entirely of reusable core elements, many of which are already flight-proven. It incorporates a router with 4 SpaceWire ports and two local ports, dual PC1 bus interfaces, a microcontroller, 32KB of internal memory, and a memory controller for additional external memory use. The SpaceWire cores are also reused in other ASICs under development. The SpaceWire ASIC is planned for use on the Geostationary Operational Environmental Satellites (GOES)-R, the Lunar Reconnaissance Orbiter (LRO) and other missions. Engineering and flight parts have been delivered to programs and users. This paper reviews the SpaceWire protocol and those elements of it that have been built into the current and next SpaceWire reusable cores and features within the core that go beyond the current standard and can be enabled or disabled by the user. The adaptation of SpaceWire to BAE Systems' On Chip Bus (OCB) for compatibility with the other reusable cores will be reviewed and highlighted. Optional configurations within user systems and test boards will be shown. The physical implementation of the design will be described and test results from the hardware will be discussed. Application of this ASIC and other ASICs containing the SpaceWire cores and embedded microcontroller to Plug and Play and reconfigurable implementations will be described. Finally, the BAE Systems roadmap for SpaceWire developments will be updated, including some products already in design as well as longer term plans.

Development of a portable computed tomographic scanner for on-line imaging of industrial piping systems

International Nuclear Information System (INIS)

Jaafar Abdullah; Mohd Arif Hamzah; Mohd Soyapi Mohd Yusof; Mohd Fitri Abdul Rahman; Fadil IsmaiI; Rasif Mohd Zain

2003-01-01

Computed tomography (CT) technology is being increasingly developed for industrial application. This paper presents the development of a portable computed tomographic scanner for on?line imaging of industrial piping systems. The theoretical approach, the system hardware, the data acquisition system and the adopted algorithm for image reconstruction are discussed. The scanner has large potential to be used to determine the extent of corrosion under insulation (CUI), to detect blockages, to measure the thickness of deposit/materials built-up on the walls and to improve understanding of material flow in pipelines. (Author)

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...

A space release/deployment system actuated by shape memory wires

Science.gov (United States)

Fragnito, Marino; Vetrella and, Sergio

2002-11-01

In this paper, the design of an innovative hold down/release and deployment device actuated by shape memory wires, to be used for the first time for the S MA RT microsatellite solar wings is shown. The release and deployment mechanisms are actuated by a Shape Memory wire (Nitinol), which allows a complete symmetrical and synchronous release, in a very short time, of the four wings in pairs. The hold down kinematic mechanism is preloaded to avoid vibration nonlinearities and unwanted deployment at launch. The deployment mechanism is a simple pulley system. The stiffness of the deployed panel-hinge system needs to be dimensioned in order to meet the on-orbit requirement for attitude control. One-way roller clutches are used to keep the panel at the desired angle during the mission. An ad hoc software has been developed to simulate both the release and deployment operations, coupling the SMA wire behavior with the system mechanics.

Multi Optical Transition Radiation System for ATF2

International Nuclear Information System (INIS)

Alabau-Gonzalvo, Javier

2012-01-01

In this paper we describe the design, installation and first calibration tests of a Multi Optical Transition Radiation System in the beam diagnostic section of the Extraction (EXT) line of ATF2, close to the multi wire scanner system. This system will be a valuable tool for measuring beam sizes and emittances coming from the ATF Damping Ring. With an optical resolution of about 2 (micro)m an original OTR design (OTR1X) located after the septum at the entrance of the EXT line demonstrated the ability to measure a 5.5 (micro)m beam size in one beam pulse and to take many fast measurements. This gives the OTR the ability to measure the beam emittance with high statistics, giving a low error and a good understanding of emittance jitter. Furthermore the nearby wire scanners will be a definitive test of the OTR as a beam emittance diagnostic device. The multi-OTR system design proposed here is based on the existing OTR1X.

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...

A combined positron emission tomography (PET)- electron paramagnetic resonance imaging (EPRI) system: initial evaluation of a prototype scanner.

Science.gov (United States)

Tseytlin, Mark; Stolin, Alexander V; Guggilapu, Priyaankadevi; Bobko, Andrey A; Khramtsov, Valery V; Tseytlin, Oxana; Raylman, Raymond R

2018-04-20

The advent of hybrid scanners, combining complementary modalities, has revolutionized imaging; enhancing clinical practice and biomedical research. In this project, we investigated the melding of two complementary, functional imaging methods: positron emission tomography (PET) and electron paramagnetic resonance imaging (EPRI). The PET radiotracers can provide important information about cellular parameters, such as glucose metabolism. While EPR probes can provide assessment of tissue microenvironment, measuring parameters such as oxygenation and pH, for example. A combined PET/EPRI scanner has the promise to provide new insights not attainable with current imagers by simultaneous acquisition of multiple components of tissue microenvironments. In this investigation, a prototype system was created by combing two existing scanners, modified for simultaneous imaging. Specifically, a silicon photomultiplier (SiPM) based PET scanner ring designed as a portable scanner was combined with an EPRI scanner designed for the imaging of small animals. The ability of the system to obtain simultaneous images was assessed with a small phantom consisting of four cylinders containing both PET and EPR tracers. The resulting images demonstrated the ability to obtain contemporaneous PET and ERP images without cross-modality interference. The next step in this project is the construction of pre-clinical PET/EPRI scanner for multi-parametric assessment of physiologically important parameters of tissue microenvironments. . © 2018 Institute of Physics and Engineering in Medicine.

A combined positron emission tomography (PET)-electron paramagnetic resonance imaging (EPRI) system: initial evaluation of a prototype scanner

Science.gov (United States)

Tseytlin, Mark; Stolin, Alexander V.; Guggilapu, Priyaankadevi; Bobko, Andrey A.; Khramtsov, Valery V.; Tseytlin, Oxana; Raylman, Raymond R.

2018-05-01

The advent of hybrid scanners, combining complementary modalities, has revolutionized the application of advanced imaging technology to clinical practice and biomedical research. In this project, we investigated the melding of two complementary, functional imaging methods: positron emission tomography (PET) and electron paramagnetic resonance imaging (EPRI). PET radiotracers can provide important information about cellular parameters, such as glucose metabolism. While EPR probes can provide assessment of tissue microenvironment, measuring oxygenation and pH, for example. Therefore, a combined PET/EPRI scanner promises to provide new insights not attainable with current imagers by simultaneous acquisition of multiple components of tissue microenvironments. To explore the simultaneous acquisition of PET and EPR images, a prototype system was created by combining two existing scanners. Specifically, a silicon photomultiplier (SiPM)-based PET scanner ring designed as a portable scanner was combined with an EPRI scanner designed for the imaging of small animals. The ability of the system to obtain simultaneous images was assessed with a small phantom consisting of four cylinders containing both a PET tracer and EPR spin probe. The resulting images demonstrated the ability to obtain contemporaneous PET and EPR images without cross-modality interference. Given the promising results from this initial investigation, the next step in this project is the construction of the next generation pre-clinical PET/EPRI scanner for multi-parametric assessment of physiologically-important parameters of tissue microenvironments.

Design of Model-based Controller with Disturbance Estimation in Steer-by-wire System

Directory of Open Access Journals (Sweden)

Jung Sanghun

2018-01-01

Full Text Available The steer-by-wire system is a next generation steering control technology that has been actively studied because it has many advantages such as fast response, space efficiency due to removal of redundant mechanical elements, and high connectivity with vehicle chassis control, such as active steering. Steer-by-wire system has disturbance composed of tire friction torque and self-aligning torque. These disturbances vary widely due to the weight or friction coefficient change. Therefore, disturbance compensation logic is strongly required to obtain desired performance. This paper proposes model-based controller with disturbance compensation to achieve the robust control performance. Targeted steer-by-wire system is identified through the experiment and system identification method. Moreover, model-based controller is designed using the identified plant model. Disturbance of targeted steer-by-wire is estimated using disturbance observer(DOB, and compensate the estimated disturbance into control input. Experiment of various scenarios are conducted to validate the robust performance of proposed model-based controller.

In-Situ Wire Damage Detection System

Science.gov (United States)

Williams, Martha K. (Inventor); Roberson, Luke B. (Inventor); Tate, Lanetra C. (Inventor); Smith, Trent M. (Inventor); Gibson, Tracy L. (Inventor); Jolley, Scott T. (Inventor); Medelius, Pedro J. (Inventor)

2014-01-01

An in-situ system for detecting damage in an electrically conductive wire. The system includes a substrate at least partially covered by a layer of electrically conductive material forming a continuous or non-continuous electrically conductive layer connected to an electrical signal generator adapted to delivering electrical signals to the electrically conductive layer. Data is received and processed to identify damage to the substrate or electrically conductive layer. The electrically conductive material may include metalized carbon fibers, a thin metal coating, a conductive polymer, carbon nanotubes, metal nanoparticles or a combination thereof.

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

Flywheel system using wire-wound rotor

Science.gov (United States)

Chiao, Edward Young; Bender, Donald Arthur; Means, Andrew E.; Snyder, Philip K.

2016-06-07

A flywheel is described having a rotor constructed of wire wound onto a central form. The wire is prestressed, thus mitigating stresses that occur during operation. In another aspect, the flywheel incorporates a low-loss motor using electrically non-conducting permanent magnets.

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)

A design and construction of wire drive mechanical barrier system on the medium dose brachytherapy for cervical cancer

International Nuclear Information System (INIS)

Nur Khasan; Tri Harjanto; Ari Satmoko

2012-01-01

A design and construction of wire drive mechanical barrier system on the medium dose brachytherapy for cervical cancer has been done as a complete system for security of both mechanically and electrically during the operation of the device as a whole. The design and construction were carried out by paying attention to the length of wire dimensions, the diameter of the roller drum for wire, the process of wire rolling and delivery path length of the radioactive source or also the checker. The length dimension of wire or delivery path length with a diameter of drum rollers which is converted into 2 pieces of limiting the size of the circular line on the gear system is integrated with the limit switch/divider electrically. By using this barrier the security and certainty of the wire rolling and delivery process are assured, either wire of radioactive sources or also wire of checker. The materials or components used are aluminum for gear system and limit switches for electrical systems. The result of the construction is a set of equipment that is used to complete a safety facility operating on the wire drive module of medium dose brachytherapy for cervical cancer. (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.

A Gender Identification System for Customers in a Shop Using Infrared Area Scanners

Science.gov (United States)

Tajima, Takuya; Kimura, Haruhiko; Abe, Takehiko; Abe, Koji; Nakamoto, Yoshinori

Information about customers in shops plays an important role in marketing analysis. Currently, in convenience stores and supermarkets, the identification of customer's gender is examined by clerks. On the other hand, gender identification systems using camera images are investigated. However, these systems have a problem of invading human privacies in identifying attributes of customers. The proposed system identifies gender by using infrared area scanners and Bayesian network. In the proposed system, since infrared area scanners do not take customers' images directly, invasion of privacies are not occurred. The proposed method uses three parameters of height, walking speed and pace for humans. In general, it is shown that these parameters have factors of sexual distinction in humans, and Bayesian network is designed with these three parameters. The proposed method resolves the existent problems of restricting the locations where the systems are set and invading human privacies. Experimental results using data obtained from 450 people show that the identification rate for the proposed method was 91.3% on the average of both of male and female identifications.

The simulation of a data acquisition system for a proposed high resolution PET scanner

Energy Technology Data Exchange (ETDEWEB)

Rotolo, C.; Larwill, M.; Chappa, S. [Fermi National Accelerator Lab., Batavia, IL (United States); Ordonez, C. [Chicago Univ., IL (United States)

1993-10-01

The simulation of a specific data acquisition (DAQ) system architecture for a proposed high resolution Positron Emission Tomography (PET) scanner is discussed. Stochastic processes are used extensively to model PET scanner signal timing and probable DAQ circuit limitations. Certain architectural parameters, along with stochastic parameters, are varied to quantatively study the resulting output under various conditions. The inclusion of the DAQ in the model represents a novel method of more complete simulations of tomograph designs, and could prove to be of pivotal importance in the optimization of such designs.

The simulation of a data acquisition system for a proposed high resolution PET scanner

International Nuclear Information System (INIS)

Rotolo, C.; Larwill, M.; Chappa, S.; Ordonez, C.

1993-10-01

The simulation of a specific data acquisition (DAQ) system architecture for a proposed high resolution Positron Emission Tomography (PET) scanner is discussed. Stochastic processes are used extensively to model PET scanner signal timing and probable DAQ circuit limitations. Certain architectural parameters, along with stochastic parameters, are varied to quantatively study the resulting output under various conditions. The inclusion of the DAQ in the model represents a novel method of more complete simulations of tomograph designs, and could prove to be of pivotal importance in the optimization of such designs

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.

Use of digital impression systems with intraoral scanners for fabricating restorations and fixed dental prostheses.

Science.gov (United States)

Takeuchi, Yoshimasa; Koizumi, Hiroyasu; Furuchi, Mika; Sato, Yohei; Ohkubo, Chikahiro; Matsumura, Hideo

2018-01-01

Accurate impressions are essential in fabri-cating dental restorations and fixed dental prostheses. During the last decade, digital impression systems have improved substantially. This review discusses the accuracy of digital impression systems for fabrication of dental restorations and fixed dental prostheses. A literature search in PubMed was performed for the period from July 2010 through June 2017. The search keywords were Cerec, digital impression, direct digitalization, indirect digitalization, and intraoral scanner. Only relevant studies are summarized and discussed in this review. In general, the latest systems have considerably reduced the time required for impression making, and the accuracy and marginal fit of digital impression systems have recently improved. Restorations and fixed dental prostheses fabricated with currently available digital impression systems and intraoral scanners exhibit clinically acceptable ranges of marginal gap in both direct and indirect procedures.

Wire system ageing assessment and condition monitoring (WASCO)

International Nuclear Information System (INIS)

Ekelund, M; Gedde, U.W.; Fantoni, P.F.

2011-05-01

Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. In this report 3 techniques for cable global ageing assessment were tested and evaluated. The EAB technique is a destructive, local technique that is often used as a reference for other methods. The indenter is a local, in-situ mechanical technique that is currently quite often used in NPPs. LIRA is an electrical method, full line, in-situ. LIRA correlated quite well with EAB and both tend to flatten when the ageing time reaches 40 years. The only cable type that was difficult to assess for all the 3 methods was the medium type in air environment. These tests considered only thermal ageing, up to 50 years and should be completed by considering also gamma irradiation ageing. (Author)

Wire system ageing assessment and condition monitoring (WASCO)

Energy Technology Data Exchange (ETDEWEB)

Ekelund, M; Gedde, U.W. (Royal Institute of Technology (KTH). Fibre and Polymer Technology, School of Chemical Science and Engineering, Stockholm (Sweden)); Fantoni, P.F. (Institute for Energy Technology (IFE), Halden (Norway))

2011-05-15

Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. In this report 3 techniques for cable global ageing assessment were tested and evaluated. The EAB technique is a destructive, local technique that is often used as a reference for other methods. The indenter is a local, in-situ mechanical technique that is currently quite often used in NPPs. LIRA is an electrical method, full line, in-situ. LIRA correlated quite well with EAB and both tend to flatten when the ageing time reaches 40 years. The only cable type that was difficult to assess for all the 3 methods was the medium type in air environment. These tests considered only thermal ageing, up to 50 years and should be completed by considering also gamma irradiation ageing. (Author)

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.

An Investigation of the Dose Distribution from LDR Ir-192 Wires in the Triangular Implants of the Paris System using Polymer Gel Dosimetry

Directory of Open Access Journals (Sweden)

Azizollah Rahimi

2010-12-01

Full Text Available Introduction: Polymer gels are modern dosimeters providing three dimensional dose distributions. These dosimeters can be used in brachytherapy in which the tumor dimension is relatively small and the dose gradient is high. In this study, the ability of the MAGICA polymer gel was investigated for assessing the absolute dose values as well as the dose distribution of low dose rate (LDR Ir-192 wires in interstitial brachytherapy based in triangular implants of the Paris system. Material and Methods: A suitable phantom was made from Perspex. Glass tubes were used as the external tubes for holding the Ir-192 wires in the phantom. The MAGICA polymer gel was made and placed in the phantom. The phantom and the calibration tubes were irradiated using LDR Ir-192 wires and a Co-60 teletherapy unit respectively. They were subsequently imaged using an MRI scanner. The R2 (=1/T2 maps were extracted from several sequential T2-weighted MRI images. The dose values resulting from the polymer gel measurements at the reference points were compared with those from the common calculation method at the same points. In addition, the isodose curves resulting from gel dosimetry were compared with those from a brachytherapy treatment planning system (Flexiplan. Results: The average of the dose values measured with the gel at the reference points was 62.75% higher than those calculated at the same points. Investigating the isodose curves revealed that the maximum distance to agreement (DTAmax between the isodoses resulting from the gel and those obtained from the treatment planning system was less than 3 mm at different dose levels. Discussion and Conclusion: Although the MAGICA gel indicates a higher absolute dose value than those calculated commonly, it can give the relative dose values accurately. Therefore, it can be recommended to be used for the assessment of dose distributions for the treatment of tissues as well as quality control of the treatment planning systems.

A Predictive Velocity Observer in Wire Bonder’s Control System

Directory of Open Access Journals (Sweden)

Lei Zhou

2014-01-01

Full Text Available Wire bonder is a typical high speed machine. The motion speed of XY-stage is the key factor of bonding efficiency. However, phase lag elements in the servo system limit the bandwidth and slow down the system’s response. A predictive velocity observer is proposed to compensate for those phase lags. Then, the velocity loop controller can be designed as for a servo system which does not have those phase lags. Loop gains are enlarged and bandwidth is enlarged correspondingly. Then, the motion speed is improved and settling time is decreased. Experiment results verify that the predictive velocity observer provided a significant phase lead and the performance of wire bonder is improved.

The Smartphone Brain Scanner: A Portable Real-Time Neuroimaging System

DEFF Research Database (Denmark)

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

2014-01-01

Combining low-cost wireless EEG sensors with smartphones offers novel opportunities for mobile brain imaging in an everyday context. Here we present the technical details and validation of a framework for building multi-platform, portable EEG applications with real-time 3D source reconstruction....... The system – Smartphone Brain Scanner – combines an off-the-shelf neuroheadset or EEG cap with a smartphone or tablet, and as such represents the first fully portable system for real-time 3D EEG imaging. We discuss the benefits and challenges, including technical limitations as well as details of real...

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.

Acquisition And Processing Of Range Data Using A Laser Scanner-Based 3-D Vision System

Science.gov (United States)

Moring, I.; Ailisto, H.; Heikkinen, T.; Kilpela, A.; Myllyla, R.; Pietikainen, M.

1988-02-01

In our paper we describe a 3-D vision system designed and constructed at the Technical Research Centre of Finland in co-operation with the University of Oulu. The main application fields our 3-D vision system was developed for are geometric measurements of large objects and manipulator and robot control tasks. It seems to be potential in automatic vehicle guidance applications, too. The system has now been operative for about one year and its performance has been extensively tested. Recently we have started a field test phase to evaluate its performance in real industrial tasks and environments. The system consists of three main units: the range finder, the scanner and the computer. The range finder is based on the direct measurement of the time-of-flight of a laser pulse. The time-interval between the transmitted and the received light pulses is converted into a continuous analog voltage, which is amplified, filtered and offset-corrected to produce the range information. The scanner consists of two mirrors driven by moving iron galvanometers. This system is controlled by servo amplifiers. The computer unit controls the scanner, transforms the measured coordinates into a cartesian coordinate system and serves as a user interface and postprocessing environment. Methods for segmenting the range image into a higher level description have been developed. The description consists of planar and curved surfaces and their features and relations. Parametric surface representations based on the Ferguson surface patch are studied, too.

Mobile network architecture of the long-range WindScanner system

OpenAIRE

Vasiljevic, Nikola; Lea, Guillaume; Hansen, Per; Jensen, Henrik M.

2016-01-01

In this report we have presented the network architecture of the long-range WindScanner system that allows utilization of mobile network connections without the use of static public IP addresses. The architecture mitigates the issues of additional fees and contractual obligations that are linked to the acquisition of the mobile network connections with static public IP addresses. The architecture consists of a hardware VPN solution based on the network appliances Z1 and MX60 from Cisco Meraki...

Wire chamber requirements and tracking simulation studies for tracking systems at the superconducting super collider

International Nuclear Information System (INIS)

Hanson, G.G.; Niczyporuk, B.B.; Palounek, A.P.T.

1989-02-01

Limitations placed on wire chambers by radiation damage and rate requirements in the SSC environment are reviewed. Possible conceptual designs for wire chamber tracking systems which meet these requirements are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. Such computer simulation studies are necessary to determine the feasibility of wire chamber tracking systems for complex events in a high-rate environment such as the SSC. 11 refs., 9 figs., 1 tab

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.

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.

Computerized literature reference system: use of an optical scanner and optical character recognition software.

Science.gov (United States)

Lossef, S V; Schwartz, L H

1990-09-01

A computerized reference system for radiology journal articles was developed by using an IBM-compatible personal computer with a hand-held optical scanner and optical character recognition software. This allows direct entry of scanned text from printed material into word processing or data-base files. Additionally, line diagrams and photographs of radiographs can be incorporated into these files. A text search and retrieval software program enables rapid searching for keywords in scanned documents. The hand scanner and software programs are commercially available, relatively inexpensive, and easily used. This permits construction of a personalized radiology literature file of readily accessible text and images requiring minimal typing or keystroke entry.

High-speed micro electrode tool fabrication by a twin-wire EDM system

International Nuclear Information System (INIS)

Sheu, Dong-Yea

2008-01-01

This paper describes a new machining process which combines twin-electro-wire together with two electro discharge circuits to rapidly fabricate micro electrode tools. The results show that transistor electro discharge and RC electro discharge circuits coexist to fabricate micro tools with rough and finish machining both on the same machine. Compared to conventional wire electro discharge grinding (WEDG) technology, a twin-wire EDM system that combines rough and finish machining into one process allows the efficient fabrication of micro tools. This high-speed micro tool fabrication process can be applied not only to micro electrode machining but also to micro punching tool and micro probing tips machining

System Level Design of a Continuous-Time Delta-Sigma Modulator for Portable Ultrasound Scanners

DEFF Research Database (Denmark)

Llimos Muntal, Pere; Færch, Kjartan; Jørgensen, Ivan Harald Holger

2015-01-01

In this paper the system level design of a continuous-time ∆Σ modulator for portable ultrasound scanners is presented. The overall required signal-to-noise ratio (SNR) is derived to be 42 dB and the sampling frequency used is 320 MHz for an oversampling ratio of 16. In order to match these requir......, based on high-level VerilogA simulations, the performance of the ∆Σ modulator versus various block performance parameters is presented as trade-off curves. Based on these results, the block specifications are derived.......In this paper the system level design of a continuous-time ∆Σ modulator for portable ultrasound scanners is presented. The overall required signal-to-noise ratio (SNR) is derived to be 42 dB and the sampling frequency used is 320 MHz for an oversampling ratio of 16. In order to match...

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

Quasiparticle properties of a coupled quantum-wire electron-phonon system

DEFF Research Database (Denmark)

Hwang, E. H.; Hu, Ben Yu-Kuang; Sarma, S. Das

1996-01-01

We study leading-order many-body effects of longitudinal-optical phonons on electronic properties of one-dimensional quantum-wire systems. We calculate the quasiparticle properties of a weakly polar one-dimensional electron gas in the presence of both electron-phonon and electron-electron interac......We study leading-order many-body effects of longitudinal-optical phonons on electronic properties of one-dimensional quantum-wire systems. We calculate the quasiparticle properties of a weakly polar one-dimensional electron gas in the presence of both electron-phonon and electron......-electron interactions, The leading-order dynamical screening approximation (GW approximation) is used to obtain the electron self-energy, the quasiparticle spectral function, and the quasiparticle damping rate in our calculation by treating electrons and phonons on an equal footing. Our theory includes effects (within...... theoretical results for quasiparticle properties....

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.

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

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

A laser-wire system for the International Linear Collider

Indian Academy of Sciences (India)

A new laser-wire has been installed in the extraction line of the ATF at KEK. It aims at demonstrating ... beam size measurements to extract the phase space of the electron and positron ... the laser-wire (LW), instead of a conventional solid wire.

Coherent transport in a system of periodic linear chain of quantum dots situated between two parallel quantum wires

International Nuclear Information System (INIS)

Petrosyan, Lyudvig S

2016-01-01

We study coherent transport in a system of periodic linear chain of quantum dots situated between two parallel quantum wires. We show that the resonant-tunneling conductance between the wires exhibits a Rabi splitting of the resonance peak as a function of Fermi energy in the wires. This effect is an electron transport analogue of the Rabi splitting in optical spectra of two interacting systems. The conductance peak splitting originates from the anticrossing of Bloch bands in a periodic system that is caused by a strong coupling between the electron states in the quantum dot chain and quantum wires. (paper)

Wire compensation: Performance, SPS MDs, pulsed system

CERN Document Server

Dorda, U

2008-01-01

A wire compensation (BBLR) scheme has been proposed in order to improve the long range beam-beam performance of the nominal LHC and its phase 1 and phase 2 upgrades[1]. In this paper we present experimental experience of the CERN SPS wires (BBLR) and report on progress with the RF BBLR.

Operation and force analysis of the guide wire in a minimally invasive vascular interventional surgery robot system

Science.gov (United States)

Yang, Xue; Wang, Hongbo; Sun, Li; Yu, Hongnian

2015-03-01

To develop a robot system for minimally invasive surgery is significant, however the existing minimally invasive surgery robots are not applicable in practical operations, due to their limited functioning and weaker perception. A novel wire feeder is proposed for minimally invasive vascular interventional surgery. It is used for assisting surgeons in delivering a guide wire, balloon and stenting into a specific lesion location. By contrasting those existing wire feeders, the motion methods for delivering and rotating the guide wire in blood vessel are described, and their mechanical realization is presented. A new resistant force detecting method is given in details. The change of the resistance force can help the operator feel the block or embolism existing in front of the guide wire. The driving torque for rotating the guide wire is developed at different positions. Using the CT reconstruction image and extracted vessel paths, the path equation of the blood vessel is obtained. Combining the shapes of the guide wire outside the blood vessel, the whole bending equation of the guide wire is obtained. That is a risk criterion in the delivering process. This process can make operations safer and man-machine interaction more reliable. A novel surgery robot for feeding guide wire is designed, and a risk criterion for the system is given.

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.

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

A Novel Methodology to Validate the Accuracy of Extraoral Dental Scanners and Digital Articulation Systems.

Science.gov (United States)

Ellakwa, A; Elnajar, S; Littlefair, D; Sara, G

2018-05-03

The aim of the current study is to develop a novel method to investigate the accuracy of 3D scanners and digital articulation systems. An upper and a lower poured stone model were created by taking impression of fully dentate male (fifty years old) participant. Titanium spheres were added to the models to allow for an easily recognisable geometric shape for measurement after scanning and digital articulation. Measurements were obtained using a Coordinate Measuring Machine to record volumetric error, articulation error and clinical effect error. Three scanners were compared, including the Imetric 3D iScan d104i, Shining 3D AutoScan-DS100 and 3Shape D800, as well as their respective digital articulation software packages. Stoneglass Industries PDC digital articulation system was also applied to the Imetric scans for comparison with the CMM measurements. All the scans displayed low volumetric error (p⟩0.05), indicating that the scanners themselves had a minor contribution to the articulation and clinical effect errors. The PDC digital articulation system was found to deliver the lowest average errors, with good repeatability of results. The new measuring technique in the current study was able to assess the scanning and articulation accuracy of the four systems investigated. The PDC digital articulation system using Imetric scans was recommended as it displayed the lowest articulation error and clinical effect error with good repeatability. The low errors from the PDC system may have been due to its use of a 3D axis for alignment rather than the use of a best fit. Copyright© 2018 Dennis Barber Ltd.

Microscopy system of atomic force based on a digital optical reading unit and a buzzer-scanner

International Nuclear Information System (INIS)

Dabirian, R.; Loza M, D.; Wang, W. M.; Hwu, E. T.

2015-01-01

An astigmatic detection system (Ads) based on a compact disk/digital-versatile-disk (Cd-DVD) astigmatic optical pickup unit is presented. It can achieve a resolution better than 0.3 nm in detection of the vertical displacement and is able to detect the two-dimensional angular tilt of the object surface. Furthermore, a novel scanner design actuated by piezoelectric disk buzzers is presented. The scanner is composed of a quad-rod actuation structure and several piezoelectric disks. It can be driven directly with low-voltage and low-current sources, such as analogue outputs of a data acquisition card and enables a sufficient scanning range of up to μm. In addition, an economic, high-performance streamlined atomic force microscopy (AFM) was constructed, using the buzzer-scanner to move the sample relative to the probe, and using a Cd/DVD optical pickup unit to detect the mechanical resonance of a micro fabricated cantilever. The performance of the AFM is evaluated. The high sensitivity and high bandwidth of the detection system makes the equipment suitable for characterizing nano scale elements. An AFM using our detection system for detecting the deflection of micro fabricated cantilevers can resolve individual atomic steps on graphite surfaces. (Author)

Development of contact scanner for Wolsung NPP alarm and annunciation system

Energy Technology Data Exchange (ETDEWEB)

Oh, Eung Se [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

1995-12-31

Contact scanner system in Wolsung NPP(model ESE-1565) is early `70 equipment so most of components are obsolete. To make 100% compatible PCBs for this system is main object of the study. Most of components used in the system are now not available in the electric market, furthermore original system maker no longer supplies spare parts. System supplier(AECL) quoted lots of money than general PCBs prices in case of spare PCBs are re-marked by canada maker. Contents and scope of the study are specifications research and system analysis, improvements of repairability and reliability, circuit design and simulations using computer aided tools(CAE), make arbitrary mechanical contacts signal generator for test system. Now the long-run test of home made PCBs are conducting at Wolsung NPP. (author). 20 refs., 42 figs.

Avaliação da transmissão de dados de temperatura no sistema 1-wireTM Evaluation of the temperature data transmission in the 1-wireTM system

Directory of Open Access Journals (Sweden)

Antonio J. Steidle Neto

2005-04-01

Full Text Available A necessidade de sistemas de monitoramento automático versáteis e de baixo custo que possam auxiliar o produtor agrícola na otimização dos processos produtivos, é evidente. Este trabalho foi realizado com o objetivo de pesquisar as limitações e as potencialidades de aplicação do sistema 1-wireTM na transmissão de dados de temperatura em instalações agrícolas. O sistema 1-wireTM é uma rede de transmissão de dados que possibilita a comunicação digital entre um computador e dispositivos da série 1-wireTM, tais como os sensores de temperatura DS1820. A transmissão de dados de temperatura nesse sistema foi avaliada em função do tipo dos condutores e do número de sensores DS1820. Com base nos resultados, concluiu-se que o aumento do número de sensores de temperatura DS1820 no sistema 1-wireTM incrementa a carga capacitiva de maneira distinta para cada um dos tipos de condutores estudados, podendo causar interrupções na transmissão de dados.The need of versatile and low cost automatic monitoring systems for the optimization of the agricultural productive processes is evident. This work was carried out to evaluate the limitations and potentialities of the 1-wireTM system for temperature data transmission in agricultural buildings. The 1-wireTM system is a data transmission network, which makes possible the digital communication between a computer and devices of the 1-wireTM series, such as the temperature DS1820 sensors. The temperature data transmission in this system was evaluated as a function of types of conductors and the number of DS1820 sensors. Based on the results, it was concluded that, by increasing the number of the DS1820 temperature sensors in the 1-wireTM system, the capacitive load increases in a different way for each conductor and can cause interruptions during temperature data transmission.

A Laser-Wire System for the International Linear Collider

International Nuclear Information System (INIS)

Delerue, N.; Dixit, S.; Gannaway, F.; Howell, D.; Qurshi, M.; Blair, G.; Boogert, S.; Boorman, G.; Driouichi, C.; Deacon, L.; Aryshev, A.; Karataev, P.; Terunuma, N.; Urakawa, J.; Brachmann, A.; Frisch, J.; Ross, M.

2009-01-01

A new laser-wire has been installed in the extraction line of the ATF at KEK. It aims at demonstrating that laser-wires can be used to measure micrometre scale beam size. In parallel, studies have been made to specify a laser suitable for the ILC laser-wires.

A laser-wire system for the International Linear Collider

Indian Academy of Sciences (India)

A new laser-wire has been installed in the extraction line of the ATF at KEK. It aims at demonstrating that laser-wires can be used to measure micrometre scale beam size. In parallel, studies have been made to specify a laser suitable for the ILC laser-wires.

Comparison of H-infinity control and generalized predictive control for a laser scanner system

DEFF Research Database (Denmark)

Ordys, A.W.; Stoustrup, Jakob; Smillie, I.

2000-01-01

This paper describes tests performed on a laser scanner system to assess the feasibility of H-infinity control and generalized predictive control design techniques in achieving a required performance in a trajectory folowing problem. The two methods are compared with respect to achieved scan times...

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)

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.

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

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.

Mechanization of and experience with a triplex fly-by-wire backup control system

Science.gov (United States)

Lock, W. P.; Petersen, W. R.; Whitman, G. B.

1976-01-01

A redundant three axis analog control system was designed and developed to back up a digital fly by wire control system for an F-8C airplane. The mechanization and operational experience with the backup control system, the problems involved in synchronizing it with the primary system, and the reliability of the system are discussed. The backup control system was dissimilar to the primary system, and it provided satisfactory handling through the flight envelope evaluated. Limited flight tests of a variety of control tasks showed that control was also satisfactory when the backup control system was controlled by a minimum displacement (force) side stick. The operational reliability of the F-8 digital fly by wire control system was satisfactory, with no unintentional downmodes to the backup control system in flight. The ground and flight reliability of the system's components is discussed.

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.)

Description and Flight Test Results of the NASA F-8 Digital Fly-by-Wire Control System

Science.gov (United States)

1975-01-01

A NASA program to develop digital fly-by-wire (DFBW) technology for aircraft applications is discussed. Phase I of the program demonstrated the feasibility of using a digital fly-by-wire system for aircraft control through developing and flight testing a single channel system, which used Apollo hardware, in an F-8C airplane. The objective of Phase II of the program is to establish a technology base for designing practical DFBW systems. It will involve developing and flight testing a triplex digital fly-by-wire system using state-of-the-art airborne computers, system hardware, software, and redundancy concepts. The papers included in this report describe the Phase I system and its development and present results from the flight program. Man-rated flight software and the effects of lightning on digital flight control systems are also discussed.

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)

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 Wire Position Monitor System for the ISAC-II Cryomodule Components Alignment

CERN Document Server

Rawnsley, B; Dutto, G; Fong, K; Laxdal, R E; Ries, T

2004-01-01

TRIUMF is developing ISAC-II, a superconducting (SC) linac. It will comprise 9 cryomodules with a total of 48 niobium cavities and 12 SC solenoids. They must remain aligned at liquid He temperatures: cavities to ±400 μm and solenoids to ±200 μm after a vertical contraction of ~4 mm. A wire position monitor (WPM) system based on a TESLA design has been developed, built, and tested with a prototype cryomodule. The system is based on the measurement of signals induced in pickups by a 215 MHz signal carried by a wire through the WPMs. The wire is stretched between the warm tank walls parallel to the beam axis providing a position reference. The sensors, one per cavity and two per solenoid, are attached to the cold elements to monitor their motion during pre-alignment, pumping and cool down. A WPM consists of four 50 Ω striplines spaced 90° apart. A GaAs multiplexer scans the WPMs and a Bergoz card converts the RF signals to DC X and Y voltages. National Ins...

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.

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.

Steer-by-wire innovations and demonstrator

NARCIS (Netherlands)

Lupker, H.A.; Zuurbier, J.; Verschuren, R.M.A.F.; Jansen, S.T.H.; Willemsen, D.M.C.

2002-01-01

Arguments for 'by-wire' systems include production costs, packaging and traffic safety. Innovations concern both product and development process e.g. combined virtual engineering and Hardware-in-the-loop testing. Three Steer-by-wire systems are discussed: a steering system simulator used as a

Error-tolerant pedal for a brake-by-wire system; Fehlertolerante Pedaleinheit fuer ein elektromechanisches Bremssystem (Brake-by-Wire)

Energy Technology Data Exchange (ETDEWEB)

Stoelzl, S.

2000-07-01

The author describes the development of an error-tolerant brake-by-wire system with pedal consolidation, including the development of a monitoring and safety concept. [German] Die zunehmende Entwicklung aktiver Fahrerassistenzsysteme im Automobilbereich (z.B. ABS, ESP) zur Erhoehung der Fahrsicherheit erfordert ein staendig wachsendes Funktionspotential. Die Bremsanlagen werden dadurch immer komplexer. Parallel steigen die Anforderungen an den Bremspedalkomfort. Einen Ausweg aus dieser Problematik verspricht die Elektromechanische Bremsanlage (EMB) mit rueckwirkungsfreier Entkopplung des Fahrers von den Radbremsen (Brake-by-Wire). Das Bremskommando des Fahrers wird bei Betaetigung des Bremspedals rein sensorisch erfasst. Da es keine mechanische Rueckfallebene mehr gibt, muessen Fehler der Pedaleinheit erkannt und toleriert werden. Neu an dieser Arbeit ist die Entwicklung der fehlertoleranten elektromechanischen Pedaleinheit der EMB mit Pedalsensorkonsolidierung und Erstellung des dazu notwendigen Sicherheits- und Ueberwachungskonzepts. (orig.)

A design study for an advanced ocean color scanner system. [spaceborne equipment

Science.gov (United States)

Kim, H. H.; Fraser, R. S.; Thompson, L. L.; Bahethi, O.

1980-01-01

Along with a colorimetric data analysis scheme, the instrumental parameters which need to be optimized in future spaceborne ocean color scanner systems are outlined. With regard to assessing atmospheric effects from ocean colorimetry, attention is given to computing size parameters of the aerosols in the atmosphere, total optical depth measurement, and the aerosol optical thickness. It is suggested that sensors based on the use of linear array technology will meet hardware objectives.

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

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

Measurement properties and usability of non-contact scanners for measuring transtibial residual limb volume.

Science.gov (United States)

Kofman, Rianne; Beekman, Anna M; Emmelot, Cornelis H; Geertzen, Jan H B; Dijkstra, Pieter U

2018-06-01

Non-contact scanners may have potential for measurement of residual limb volume. Different non-contact scanners have been introduced during the last decades. Reliability and usability (practicality and user friendliness) should be assessed before introducing these systems in clinical practice. The aim of this study was to analyze the measurement properties and usability of four non-contact scanners (TT Design, Omega Scanner, BioSculptor Bioscanner, and Rodin4D Scanner). Quasi experimental. Nine (geometric and residual limb) models were measured on two occasions, each consisting of two sessions, thus in total 4 sessions. In each session, four observers used the four systems for volume measurement. Mean for each model, repeatability coefficients for each system, variance components, and their two-way interactions of measurement conditions were calculated. User satisfaction was evaluated with the Post-Study System Usability Questionnaire. Systematic differences between the systems were found in volume measurements. Most of the variances were explained by the model (97%), while error variance was 3%. Measurement system and the interaction between system and model explained 44% of the error variance. Repeatability coefficient of the systems ranged from 0.101 (Omega Scanner) to 0.131 L (Rodin4D). Differences in Post-Study System Usability Questionnaire scores between the systems were small and not significant. The systems were reliable in determining residual limb volume. Measurement systems and the interaction between system and residual limb model explained most of the error variances. The differences in repeatability coefficient and usability between the four CAD/CAM systems were small. Clinical relevance If accurate measurements of residual limb volume are required (in case of research), modern non-contact scanners should be taken in consideration nowadays.

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…

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...

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.

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

A portable borehole temperature logging system using the four-wire resistance method

Science.gov (United States)

Erkan, Kamil; Akkoyunlu, Bülent; Balkan, Elif; Tayanç, Mete

2017-12-01

High-quality temperature-depth information from boreholes with a depth of 100 m or more is used in geothermal studies and in studies of climate change. Electrical wireline tools with thermistor sensors are capable of measuring borehole temperatures with millikelvin resolution. The use of a surface readout mode allows analysis of the thermally conductive state of a borehole, which is especially important for climatic and regional heat flow studies. In this study we describe the design of a portable temperature logging tool that uses the four-wire resistance measurement method. The four-wire method enables the elimination of cable resistance effects, thus allowing millikelvin resolution of temperature data at depth. A preliminary two-wire model of the system is also described. The portability of the tool enables one to collect data from boreholes down to 300 m, even in locations with limited accessibility.

Calculating modes of quantum wire systems using a finite difference technique

Directory of Open Access Journals (Sweden)

T Mardani

2013-03-01

Full Text Available  In this paper, the Schrodinger equation for a quantum wire is solved using a finite difference approach. A new aspect in this work is plotting wave function on cross section of rectangular cross-sectional wire in two dimensions, periodically. It is found that the correct eigen energies occur when wave functions have a complete symmetry. If the value of eigen energy has a small increase or decrease in neighborhood of the correct energy the symmetry will be destroyed and aperturbation value at the first of wave function will be observed. In addition, the demand on computer memory varies linearly with the size of the system under investigation.

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.

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

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...

Advanced optical 3D scanners using DMD technology

Science.gov (United States)

Muenstermann, P.; Godding, R.; Hermstein, M.

2017-02-01

Optical 3D measurement techniques are state-of-the-art for highly precise, non-contact surface scanners - not only in industrial development, but also in near-production and even in-line configurations. The need for automated systems with very high accuracy and clear implementation of national precision standards is growing extremely due to expanding international quality guidelines, increasing production transparency and new concepts related to the demands of the fourth industrial revolution. The presentation gives an overview about the present technical concepts for optical 3D scanners and their benefit for customers and various different applications - not only in quality control, but also in design centers or in medical applications. The advantages of DMD-based systems will be discussed and compared to other approaches. Looking at today's 3D scanner market, there is a confusing amount of solutions varying from lowprice solutions to high end systems. Many of them are linked to a very special target group or to special applications. The article will clarify the differences of the approaches and will discuss some key features which are necessary to render optical measurement systems suitable for industrial environments. The paper will be completed by examples for DMDbased systems, e. g. RGB true-color systems with very high accuracy like the StereoScan neo of AICON 3D Systems. Typical applications and the benefits for customers using such systems are described.

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

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.

Novel calibration system with sparse wires for CMB polarization receivers

International Nuclear Information System (INIS)

Tajima, O.; Nguyen, H.; Bischoff, C.; Brizius, A.; Buder, I.; Kusaka, A.

2011-01-01

B-modes in the cosmic microwave background (CMB) polarization is a smoking gun signature of the inflationary universe. To achieve better sensitivity to this faint signal, CMB polarization experiments aim to maximize the number of detector elements, resulting in a large focal plane receiver. Detector calibration of the polarization response becomes essential. It is extremely useful to be able to calibrate 'simultaneously' all detectors on the large focal plane. We developed a novel calibration system that rotates a large 'sparse' grid of metal wires, in front of and fully covering the field of view of the focal plane receiver. Polarized radiation is created via the reflection of ambient temperature from the wire surface. Since the detector has a finite beam size, the observed signal is smeared according to the beam property. The resulting smeared polarized radiation has a reasonable intensity (a few Kelvin or less) compared to the sky temperature (∼10 K observing condition). The system played a successful role for receiver calibration of QUIET, a CMB polarization experiment located in the Atacama desert in Chile. The successful performance revealed that this system is applicable to other experiments based on different technologies, e.g. TES bolometers.

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.

Progress in American Superconductor’s HTS wire and optimization for fault current limiting systems

Energy Technology Data Exchange (ETDEWEB)

Malozemoff, Alexis P., E-mail: amalozemoff@amsc.com

2016-11-15

Highlights: • AMSC HTS wire critical current needed for rotating machinery is doubled by 16 MeV Au irradiation. • Nonuniformity of HTS wires in power devices causes hot spot formation during power system faults. • Lower normal-state resistivity and critical current lower HTS wire hot spot heating during faults. • HTS wire hot spot heating in HTS cables during faults must stay below lN{sub 2} bubble nucleation point. • HTS wire can be designed to meet hot spot heating limits in fault current limiting cables. - Abstract: American Superconductor has developed composite coated conductor tape-shaped wires using high temperature superconductor (HTS) on a flexible substrate with laminated metal stabilizer. Such wires enable many applications, each requiring specific optimization. For example, coils for HTS rotating machinery require increased current density J at 25–50 K. A collaboration with Argonne, Brookhaven and Los Alamos National Laboratories and several universities has increased J using an optimized combination of precipitates and ion irradiation defects in the HTS. Major commercial opportunities also exist to enhance electric power grid resiliency by linking substations with distribution-voltage HTS power cables [10]. Such links provide alternative power sources if one substation's transmission-voltage power is compromised. But they must also limit fault currents which would otherwise be increased by such distribution-level links. This can be done in an HTS cable, exploiting the superconductor-to-resistive transition when current exceeds the wires’ critical J. A key insight is that such transitions are usually nonuniform; so the wire must be designed to prevent localized hot spots from damaging the wire or even generating gas bubbles in the cable causing dielectric breakdown. Analysis shows that local heating can be minimized by increasing the composite tape's total thickness, decreasing its total resistance in the normal state and

The development of a mobile CT-scanner gantry for use in the operating room

International Nuclear Information System (INIS)

Okudera, Hiroshi; Kobayashi, Shigeaki; Koike, Jouji; Harada, Takanobu; Kanemaru, Kei

1989-01-01

We report the development of a mobile CT-scanner gantry which uses a gantry platter. This system has been developed for use in the operating room. We designed a small lift to move the gantry unit of the scanner: the gantry carrier. The scanner gantry is fixed to the gantry carrier. A phantom test with a digitalized operating table worked well in the laboratory, and operating-room use showed that there was no deterioration in image quality. The mobile gantry system has been developed to increase the efficiency of the operating CT-scanner system. This system enables us to obtain CT images during surgery of immediately after surgery in the operating room, i.e., in cases that are not transferable to the radiological department. The operability is basically the same as that of a conventional mobile X-ray unit. Theoretically, this unit could be used with any CT scanner and in any operating room. (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

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.

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)

Six-state, three-level, six-fold ferromagnetic wire system

International Nuclear Information System (INIS)

Blachowicz, T.; Ehrmann, A.

2013-01-01

Six stable states at remanence were identified in iron wire samples of 6-fold spatial symmetry using micromagnetic simulations and the finite element method. Onion and domain-wall magnetic states were tailored by sample shape and guided by an applied magnetic field with a fixed in-plane direction. Different directions of externally applied magnetic fields revealed a tendency for stability or nonstability of the considered states. -- Highlights: ► In a ferromagnetic wire sample six stable states at remanence were discovered. ► Presented wires provide new effects not met in classical thin-layered solutions. ► The mechanism of working results from competing demagnetizing and exchange fields. ► For different physical conditions onion and domain-wall states were observed. ► Wire samples of 6-fold symmetry can lead to many-level information storage devices

Six-state, three-level, six-fold ferromagnetic wire system

Energy Technology Data Exchange (ETDEWEB)

Blachowicz, T., E-mail: tomasz.blachowicz@polsl.pl [Institute of Physics, Silesian University of Technology, 44-100 Gliwice (Poland); Ehrmann, A. [Faculty of Textile and Clothing Technology, Niederrhein University of Applied Sciences, 41065 Mönchengladbach (Germany)

2013-04-15

Six stable states at remanence were identified in iron wire samples of 6-fold spatial symmetry using micromagnetic simulations and the finite element method. Onion and domain-wall magnetic states were tailored by sample shape and guided by an applied magnetic field with a fixed in-plane direction. Different directions of externally applied magnetic fields revealed a tendency for stability or nonstability of the considered states. -- Highlights: ► In a ferromagnetic wire sample six stable states at remanence were discovered. ► Presented wires provide new effects not met in classical thin-layered solutions. ► The mechanism of working results from competing demagnetizing and exchange fields. ► For different physical conditions onion and domain-wall states were observed. ► Wire samples of 6-fold symmetry can lead to many-level information storage devices.

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

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.)

High-picture quality industrial CT scanner

International Nuclear Information System (INIS)

Shoji, Takao; Nishide, Akihiko; Fujii, Masashi.

1989-01-01

Industrial X-ray-CT-scanners, which provide cross-sectional images of a tested sample without destroying it, are attracting attention as a new nondestructive inspection device. In 1982, Toshiba commenced the development of industrial CT scanners, and introduced the 'TOSCANER' -3000 and-4000 series. Now, the state of the art 'TOSCANER'-20000 series of CT systems has been developed incorporating the latest computer tomography and image processing technology, such as the T9506 image processor. One of the advantages of this system is its applicability to a wide range of X-ray energy . The 'TOSCANER'-20000 series can be utilized for inspecting castings and other materials with relatively low-transparency to X-rays, as well as ceramics, composite materials and other materials with high X-ray transparency. A further feature of the new system is its high-picture quality, with a high-spatial resolution resulting from a pixel size of 0.2x0.2(mm). (author)

Radiation exposure and privacy concerns surrounding full-body scanners in airports

Directory of Open Access Journals (Sweden)

Julie Accardo

2014-04-01

Full Text Available Millions of people filter through airport security check points in the United States every year. These security checks, in response to the post 9/11 and 2009 “Underwear Bomber” terrorist threats, have become increasingly burdensome to the general public due to the wide spread deployment of “enhanced screening systems.” The enhanced screening systems that have generated the most controversy are the passenger “full-body scanners.” These systems enable airport security personnel to effectively detect contraband (often concealed under clothing without the physical contact necessitated by a strip search. The two types of full-body scanners (also known as Advanced Imaging Technology systems, used in airports in the United States and around the world are referred to as backscatter technology units and millimeter-wave technology units. Although their respective radiation emissions vary, both scanners serve the same purpose; that is, the detection of concealed metallic and non-metallic threats in the form of liquids, gels, plastics, etc. Although enhanced screening systems were deployed to further public safety efforts, they have also generated wide spread public concern. Specifically, these concerns address the potential of adverse health and privacy issues that may result from continued public exposure to full-body scanner systems.

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

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.

Dental impressions using 3D digital scanners: virtual becomes reality.

Science.gov (United States)

Birnbaum, Nathan S; Aaronson, Heidi B

2008-10-01

The technologies that have made the use of three-dimensional (3D) digital scanners an integral part of many industries for decades have been improved and refined for application to dentistry. Since the introduction of the first dental impressioning digital scanner in the 1980s, development engineers at a number of companies have enhanced the technologies and created in-office scanners that are increasingly user-friendly and able to produce precisely fitting dental restorations. These systems are capable of capturing 3D virtual images of tooth preparations, from which restorations may be fabricated directly (ie, CAD/CAM systems) or fabricated indirectly (ie, dedicated impression scanning systems for the creation of accurate master models). The use of these products is increasing rapidly around the world and presents a paradigm shift in the way in which dental impressions are made. Several of the leading 3D dental digital scanning systems are presented and discussed in this article.

Characterization of NbTi multifilamentary superconducting wires

International Nuclear Information System (INIS)

Vellego, G.

1988-01-01

Pirelli is developing superconducting mulfilamentary NbTi wires, with current carrying capacities of up to 500 A, for use in magnetic resonance imaging (MRI) systems and in small research magnets. Pirelli and IFUSP have developed a system for assessing wire performance, whose quality is comparable to the equivalent systems at the Brookhaven National Laboratory (BNL) and at the National Bureau of Standards (NBS). In particular, a high sensitivity is required for critical current measurements, so that the modern criteria for definition of critical current can be used. These involve conductor resistivities of the order of 10 -12 ohm-cm. The methods of measurements of critical current in applied magnetic fields, of residual resistance ratio and of copper to superconductor ratio are described. The results of the first tests performed in Pirelli wires and in wires of other manufacturers are described. These include tests on a NBS standard reference material. These results are of the same quality as results obtained at BNL or NBS on the same wires. So this system can be very useful throughout the Pirelli program. (author) [pt

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.)

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

System Security Authorization Agreement (SSAA) for the WIRE Archive and Research Facility

Science.gov (United States)

2002-01-01

The Wide-Field Infrared Explorer (WIRE) Archive and Research Facility (WARF) is operated and maintained by the Department of Physics, USAF Academy. The lab is located in Fairchild Hall, 2354 Fairchild Dr., Suite 2A103, USAF Academy, CO 80840. The WARF will be used for research and education in support of the NASA Wide Field Infrared Explorer (WIRE) satellite, and for related high-precision photometry missions and activities. The WARF will also contain the WIRE preliminary and final archives prior to their delivery to the National Space Science Data Center (NSSDC). The WARF consists of a suite of equipment purchased under several NASA grants in support of WIRE research. The core system consists of a Red Hat Linux workstation with twin 933 MHz PIII processors, 1 GB of RAM, 133 GB of hard disk space, and DAT and DLT tape drives. The WARF is also supported by several additional networked Linux workstations. Only one of these (an older 450 Mhz PIII computer running Red Hat Linux) is currently running, but the addition of several more is expected over the next year. In addition, a printer will soon be added. The WARF will serve as the primary research facility for the analysis and archiving of data from the WIRE satellite, together with limited quantities of other high-precision astronomical photometry data from both ground- and space-based facilities. However, the archive to be created here will not be the final archive; rather, the archive will be duplicated at the NSSDC and public access to the data will generally take place through that site.

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.

Wire in the Cable-Driven System of Surgical Robot

Science.gov (United States)

Wang, X. F.; Lv, N.; Mu, H. Z.; Xue, L. J.

2017-07-01

During the evolution of the surgical robot, cable plays an important role. It translates motion and force precisely from surgeon’s hand to the tool’s tips. In the paper, the vertical wires, the composition of cable, are mathematically modeled from a geometric point of view. The cable structure and tension are analyzed according to the characteristics of wire screw twist. The structural equations of the wires in different positions are derived for both non-bent cable and bent cable, respectively. The bending moment formula of bent cable is also obtained. This will help researchers find suitable cable and design more matched pulley.

Virtual Instrument Systems in Reality (VISIR) for Remote Wiring and Measurement of Electronic Circuits on Breadboard

Science.gov (United States)

Tawfik, M.; Sancristobal, E.; Martin, S.; Gil, R.; Diaz, G.; Colmenar, A.; Peire, J.; Castro, M.; Nilsson, K.; Zackrisson, J.; Hakansson, L.; Gustavsson, I.

2013-01-01

This paper reports on a state-of-the-art remote laboratory project called Virtual Instrument Systems in Reality (VISIR). VISIR allows wiring and measuring of electronic circuits remotely on a virtual workbench that replicates physical circuit breadboards. The wiring mechanism is developed by means of a relay switching matrix connected to a PCI…

Design and Experimental Research of New Type Brake by Wire System Based on Giant-magnetostrictive Material

Directory of Open Access Journals (Sweden)

Changbao CHU

2014-04-01

Full Text Available In this paper, H type brake by wire system based on giant-magnetostrictive material is designed from two aspects of hardware and software. System principle prototype is manufactured. Hardware circuit mainly includes the Sepic circuit, current detection circuit, over current protection circuit, PWM driver protection circuit. Circuit parameters can be obtained through by theoretical calculation. Pedal sensor signal is taken as main control variable, look-up table method is used for brake by wire system. The experimental results show that the system can meet the braking requirements. It proves the feasibility of the scheme.

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.

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.

Novel calibration system with sparse wires for CMB polarization receivers

Energy Technology Data Exchange (ETDEWEB)

Tajima, O.; /KEK, Tsukuba /Chicago U., KICP; Nguyen, H.; /Fermilab; Bischoff, C.; /Chicago U., KICP /Harvard-Smithsonian Ctr. Astrophys.; Brizius, A.; Buder, I.; Kusaka, A. /Chicago U., KICP

2011-07-01

B-modes in the cosmic microwave background (CMB) polarization is a smoking gun signature of the inflationary universe. To achieve better sensitivity to this faint signal, CMB polarization experiments aim to maximize the number of detector elements, resulting in a large focal plane receiver. Detector calibration of the polarization response becomes essential. It is extremely useful to be able to calibrate 'simultaneously' all detectors on the large focal plane. We developed a novel calibration system that rotates a large 'sparse' grid of metal wires, in front of and fully covering the field of view of the focal plane receiver. Polarized radiation is created via the reflection of ambient temperature from the wire surface. Since the detector has a finite beam size, the observed signal is smeared according to the beam property. The resulting smeared polarized radiation has a reasonable intensity (a few Kelvin or less) compared to the sky temperature ({approx}10 K observing condition). The system played a successful role for receiver calibration of QUIET, a CMB polarization experiment located in the Atacama desert in Chile. The successful performance revealed that this system is applicable to other experiments based on different technologies, e.g. TES bolometers.

Three-Dimensional Accuracy of Digital Static Interocclusal Registration by Three Intraoral Scanner Systems.

Science.gov (United States)

Wong, Kuan Yee; Esguerra, Roxanna Jean; Chia, Vanessa Ai Ping; Tan, Ying Han; Tan, Keson Beng Choon

2018-02-01

Prior studies have defined the accuracy of intraoral scanner (IOS) systems but the accuracy of the digital static interocclusal registration function of these systems has not been reported. This study compared the three-dimensional (3D) accuracy of the digital static interocclusal registration of 3 IOS systems using the buccal bite scan function. Three IOS systems compared were 3M TM True Definition Scanner (TDS), TRIOS Color (TRC), and CEREC AC with CEREC Omnicam (CER). Using each scanner, 7 scans (n = 7) of the mounted and articulated SLA master models were obtained. The measurement targets (SiN reference spheres and implant abutment analogs) were in the opposing models at the right (R), central (C), and left (L) regions; abutments #26 and #36, respectively. A coordinate measuring machine with metrology software compared the physical and virtual targets to derive the global 3D linear distortion between the centroids of the respective target reference spheres and abutment analogs (dR R , dR C , dR L , and dR M ) and 2D distances between the pierce points of the abutment analogs (dX M , dY M , dZ M ), with 3 measurement repetitions for each scan. Mean 3D distortion ranged from -471.9 to 31.7 μm for dR R , -579.0 to -87.0 μm for dR C , -381.5 to 69.4 μm for dR L , and -184.9 to -23.1 μm for dR M . Mean 2D distortion ranged from -225.9 to 0.8 μm for dX M , -130.6 to -126.1 μm for dY M , and -34.3 to 26.3 μm for dZ M . Significant differences were found for interarch distortions across the three systems. For dR R and dR L , all three test groups were significantly different, whereas for dR C , the TDS was significantly different from the TRC and CER. For 2D distortion, significant differences were found for dX M only. Interarch and global interocclusal distortions for the three IOS systems were significantly different. TRC performed overall the best and TDS was the worst. The interarch (dR R , dR C , dR L ) and interocclusal (dX M ) distortions observed will

Analysis of electrical explosion of wire systems for the production of ...

Indian Academy of Sciences (India)

Abstract. Nanoscience and nanotechnology continue to grow as fields of scien- ... material in large quantities, and development of nanoparticles characterization meth- ods. Exploding wire method is one such method for the production of metal and metal ... the voltage across the wire and the current flowing through the wire.

Optimization of arc-start performance by wire-feeding control for GMA welding

Energy Technology Data Exchange (ETDEWEB)

Kang, Jong Gu; Ryu, Gyeong Su; Rhee, Se Hun [Hanyang University, Seoul (Korea, Republic of); Kim, Dong Cheol; Kang, Mun Jin [Korea Institute of Industrial Technology, Incheon (Korea, Republic of); Park, Young Whan [Pukyong National University, Busan (Korea, Republic of)

2013-02-15

The wire feeding system for gas metal arc welding usually consists of a wire feeder and a torch. In many industries, the distance between the wire feeder and the torch is generally 3 m to 5 m. In a conventional wire feeder, a direct current (DC) motor is used for wire feeding. However, a significant problem with this system is the impossibility of feedback control because of inner or outer impedance. In this paper, a digital wire feeder was developed by using a DC encoder motor and a push-pull torch. An optimized wire-feeding system was also developed by experiment. The welding process was observed using a high-speed camera. The resulting wire-feeding system exhibits low spatter generation and arc stability.

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

SLAC Scanner Processor applications in the data acquisition system for the upgraded Mark II detector

International Nuclear Information System (INIS)

Barklow, T.; Glanzman, T.; Lankford, A.J.; Riles, K.

1985-09-01

The SLAC Scanner Processor is a general purpose, programmable FASTBUS crate/cable master/slave module. This device plays a central role in the readout, buffering and pre-processing of data from the upgraded Mark II detector's new central drift chamber. In addition to data readout, the SSPs assist in a variety of other services, such as detector calibration, FASTBUS system management, FASTBUS system initialization and verification, and FASTBUS module testing. 9 refs., 1 fig., 2 tabs

Welding wire velocity modelling and control using an optical sensor

DEFF Research Database (Denmark)

Nielsen, Kirsten M.; Pedersen, Tom S.

2007-01-01

In this paper a method for controlling the velocity of a welding wire at the tip of the handle is described. The method is an alternative to the traditional welding apparatus control system where the wire velocity is controlled internal in the welding machine implying a poor disturbance reduction....... To obtain the tip velocity a dynamic model of the wire/liner system is developed and verified.  In the wire/liner system it turned out that backlash and reflections are influential factors. An idea for handling the backlash has been suggested. In addition an optical sensor for measuring the wire velocity...... at the tip has been constructed. The optical sensor may be used but some problems due to focusing cause noise in the control loop demanding a more precise mechanical wire feed system or an optical sensor with better focusing characteristics....

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

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)

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)

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

Acquisition of Turbulence Data Using the DST Group Constant-Temperature Hot-Wire Anemometer System

Science.gov (United States)

2015-10-01

Turbulence intensities. uv , uw Reynolds stresses. xP, yP, zP Probe body coordinate system (right-handed). For a single-wire probe, the xP axis...Figure 8), i.e. UNCLASSIFIED DST-Group-TN-1467 UNCLASSIFIED 2 vVV += (2) and wWW += (3) Turbulence terms such as 2u , 2v , 2w , uv and uw...traverse. A very small amount of phosphoric acid can be placed on the tips of the prongs and the Wollaston wire is soldered to the prongs using a

Cutting techniques of reinforced concrete by wire sawing

International Nuclear Information System (INIS)

Miyao, Hidehiko; Komatsu, Junji; Kamiyama, Yoshinori; Yasoshima, Harunori; Kukino, Yoshinori; Yamamoto, Yuichi; Miyazaki, Takashi; Aritomi, Masanori

1995-01-01

The Research Association for Nuclear Facility Decommissioning (RANDEC) has been carrying out demonstration tests to improve current technologies for decommissioning. The conceptual dismantling system has been studied and basic cutting tests have been carried out by wire sawing. In terms of waste management and dismantling efficiency, the diamond wire saw cutting method has advantages for cutting radioactive concrete in large blocks. A conceptual design for a dismantling system for various concrete shieldings of nuclear facilities has been developed and diamond wire sawing has been designed and manufactured. The basic cutting tests by wire sawing have been carried out to obtain quantitative data, in addition to the conceptual design of a dismantling system for biological shielding of various power reactors (PWR, BWR, GCR) and cell walls of nuclear fuel cycle facilities. On the basis of the conceptual dismantling system and quantitative cutting performance data, wire sawing equipment has been manufactured for use in nuclear facilities. This study was performed on consignment for the Science and Technology Agency of Japan. (author)

Durability Evaluation of a Thin Film Sensor System With Enhanced Lead Wire Attachments on SiC/SiC Ceramic Matrix Composites

Science.gov (United States)

Lei, Jih-Fen; Kiser, J. Douglas; Singh, Mrityunjay; Cuy, Mike; Blaha, Charles A.; Androjna, Drago

2000-01-01

An advanced thin film sensor system instrumented on silicon carbide (SiC) fiber reinforced SiC matrix ceramic matrix composites (SiC/SiC CMCs), was evaluated in a Mach 0.3 burner rig in order to determine its durability to monitor material/component surface temperature in harsh environments. The sensor system included thermocouples in a thin film form (5 microns thick), fine lead wires (75 microns diameter), and the bonds between these wires and the thin films. Other critical components of the overall system were the heavy, swaged lead wire cable (500 microns diameter) that contained the fine lead wires and was connected to the temperature readout, and ceramic attachments which were bonded onto the CMCs for the purpose of securing the lead wire cables, The newly developed ceramic attachment features a combination of hoops made of monolithic SiC or SiC/SiC CMC (which are joined to the test article) and high temperature ceramic cement. Two instrumented CMC panels were tested in a burner rig for a total of 40 cycles to 1150 C (2100 F). A cycle consisted of rapid heating to 1150 C (2100 F), a 5 minute hold at 1150 C (2100 F), and then cooling down to room temperature in 2 minutes. The thin film sensor systems provided repeatable temperature measurements for a maximum of 25 thermal cycles. Two of the monolithic SiC hoops debonded during the sensor fabrication process and two of the SiC/SiC CMC hoops failed during testing. The hoops filled with ceramic cement, however, showed no sign of detachment after 40 thermal cycle test. The primary failure mechanism of this sensor system was the loss of the fine lead wire-to-thin film connection, which either due to detachment of the fine lead wires from the thin film thermocouples or breakage of the fine wire.

Digital data storage of core image using high resolution full color core scanner; Kokaizodo full color scanner wo mochiita core image no digital ka

Energy Technology Data Exchange (ETDEWEB)

Takahashi, W; Ujo, S; Osato, K; Takasugi, S [Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan)

1996-05-01

This paper reports on digitization of core images by using a new type core scanner system. This system consists of a core scanner unit (equipped with a CCD camera), a personal computer and ancillary devices. This is a modification of the old type system, with measurable core length made to 100 cm/3 scans, and resolution enhanced to 5100 pixels/m (1024 pixels/m in the old type). The camera was changed to that of a color specification, and the A/D conversion was improved to 24-bit full color. As a result of carrying out a detail reproduction test on digital images of this core scanner, it was found that objects can be identified at a level of about the size of pixels constituting the image in the case when the best contrast is obtained between the objects and the background, and that in an evaluation test on visibility of concaves and convexes on core surface, reproducibility is not very good in large concaves and convexes. 2 refs., 6 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.

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.

PPM-based System for Guided Waves Communication Through Corrosion Resistant Multi-wire Cables

Science.gov (United States)

Trane, G.; Mijarez, R.; Guevara, R.; Pascacio, D.

Novel wireless communication channels are a necessity in applications surrounded by harsh environments, for instance down-hole oil reservoirs. Traditional radio frequency (RF) communication schemes are not capable of transmitting signals through metal enclosures surrounded by corrosive gases and liquids. As an alternative to RF, a pulse position modulation (PPM) guided waves communication system has been developed and evaluated using a corrosion resistant 4H18 multi-wire cable, commonly used to descend electronic gauges in down-hole oil applications, as the communication medium. The system consists of a transmitter and a receiver that utilizes a PZT crystal, for electrical/mechanical coupling, attached to each extreme of the multi-wire cable. The modulator is based on a microcontroller, which transmits60 kHz guided wave pulses, and the demodulator is based on a commercial digital signal processor (DSP) module that performs real time DSP algorithms. Experimental results are presented, which were obtained using a 1m corrosion resistant 4H18multi-wire cable, commonly used with downhole electronic gauges in the oil sector. Although there was significant dispersion and multiple mode excitations of the transmitted guided wave energy pulses, the results show that data rates on the order of 500 bits per second are readily available employing PPM and simple communications techniques.

Force systems in the initial phase of orthodontic treatment -- a comparison of different leveling arch wires.

Science.gov (United States)

Fuck, Lars-Michael; Drescher, Dieter

2006-01-01

The determination of orthodontically-effective forces and moments places great demands on the technical equipment. Many patients report severe pain after fixed appliance insertion. Since it is assumed that pain from orthodontic appliances is associated with the force and moment levels applied to the teeth and since the occurrence of root resorption is a common therapeutic side effect, it would seem important to know the actual magnitudes of the components of the active orthodontic force systems. The aim of the present study was therefore to measure initial force systems produced by different leveling arch-wires in a complete multi-bracket appliance and to assess whether force and moment levels can be regarded as biologically acceptable or not. The actual bracket position in 42 patients was transferred onto a measurement model. Forces and moments produced by a super-elastic nickel-titanium (NiTi) archwire, a 6-strand stainless steel archwire, and a 7-strand super-elastic NiTi archwire were determined experimentally on different teeth. Average forces and moments produced by the super-elastic NiTi arch wires were found to be the highest. In spite if their larger diameter, the stranded arch wires' average force and moment levels were lower, especially that of the stranded super-elastic archwire. Nevertheless, maximum force levels sometimes exceeded recommended values in the literature and must be considered as too high. The measured arch wires' initial force systems differed significantly depending on the type of archwire and its material structure. Stranded arch wires produced lower force and moment levels, and we recommend their use in the initial phase of orthodontic treatment.

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)

An overview of NASA's digital fly-by-wire technology development program

Science.gov (United States)

Jarvis, C. R.

1976-01-01

The feasibility of using digital fly by wire systems to control aircraft was demonstrated by developing and flight testing a single channel system, which used Apollo hardware, in an F-8C test airplane. This is the first airplane to fly with a digital fly by wire system as its primary means of control and with no mechanical reversion capability. The development and flight test of a triplex digital fly by wire system, which will serve as an experimental prototype for future operational digital fly by wire systems, are underway.

Accuracy of five intraoral scanners compared to indirect digitalization.

Science.gov (United States)

Güth, Jan-Frederik; Runkel, Cornelius; Beuer, Florian; Stimmelmayr, Michael; Edelhoff, Daniel; Keul, Christine

2017-06-01

Direct and indirect digitalization offer two options for computer-aided design (CAD)/ computer-aided manufacturing (CAM)-generated restorations. The aim of this study was to evaluate the accuracy of different intraoral scanners and compare them to the process of indirect digitalization. A titanium testing model was directly digitized 12 times with each intraoral scanner: (1) CS 3500 (CS), (2) Zfx Intrascan (ZFX), (3) CEREC AC Bluecam (BLU), (4) CEREC AC Omnicam (OC) and (5) True Definition (TD). As control, 12 polyether impressions were taken and the referring plaster casts were digitized indirectly with the D-810 laboratory scanner (CON). The accuracy (trueness/precision) of the datasets was evaluated by an analysing software (Geomagic Qualify 12.1) using a "best fit alignment" of the datasets with a highly accurate reference dataset of the testing model, received from industrial computed tomography. Direct digitalization using the TD showed the significant highest overall "trueness", followed by CS. Both performed better than CON. BLU, ZFX and OC showed higher differences from the reference dataset than CON. Regarding the overall "precision", the CS 3500 intraoral scanner and the True Definition showed the best performance. CON, BLU and OC resulted in significantly higher precision than ZFX did. Within the limitations of this in vitro study, the accuracy of the ascertained datasets was dependent on the scanning system. The direct digitalization was not superior to indirect digitalization for all tested systems. Regarding the accuracy, all tested intraoral scanning technologies seem to be able to reproduce a single quadrant within clinical acceptable accuracy. However, differences were detected between the tested systems.

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

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%/�

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

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)

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.

Architectural design and reliability analysis of a fail-operational brake-by-wire system from ISO 26262 perspectives

International Nuclear Information System (INIS)

Sinha, Purnendu

2011-01-01

Next generation drive-by-wire automotive systems enabling autonomous driving will build on the fail-operational capabilities of electronics, control and software (ECS) architectural solutions. Developing such architectural designs that would meet dependability requirements and satisfy other system constraints is a challenging task and will possibly lead to a paradigm shift in automotive ECS architecture design and development activities. This aspect is becoming quite relevant while designing battery-driven electric vehicles with integrated in-wheel drive-train and chassis subsystems. In such highly integrated dependable systems, many of the primary features and functions are attributed to the highest safety critical ratings. Brake-by-wire is one such system that interfaces with active safety features built into an automobile, and which in turn is expected to provide fail-operational capabilities. In this paper, building up on the basic concepts of fail-silent and fail-operational systems design we propose a system-architecture for a brake-by-wire system with fail-operational capabilities. The design choices are supported with proper rationale and design trade-offs. Safety and reliability analysis of the proposed system architecture is performed as per the ISO 26262 standard for functional safety of electrical/electronic systems in road vehicles.

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.

Shielding design for testing room of large container scanner

International Nuclear Information System (INIS)

Liu Yisi; Miao Qitian; Zhou Liye

1997-01-01

Testing facility for large container scanner is a most advanced anti-smuggle tool. The X-ray scanning principle is adopted in this system. The X-ray was collimated a ted as a fan-shape beam. The accelerator only supplies the ray beam when the container is scanned. The irradiation time is less than one minute per test. The X-ray burst irradiation and highly collimated a ted scanning beam of this system is different from the common industrial irradiation accelerator. The shielding design of the 1:1 large container scanner introduced has better collimation level because of tri-collimation. The irradiation dose is less than 150 μGy per test, which is obviously lower than importations

Manchester Coding Option for SpaceWire: Providing Choices for System Level Design

Science.gov (United States)

Rakow, Glenn; Kisin, Alex

2014-01-01

This paper proposes an optional coding scheme for SpaceWire in lieu of the current Data Strobe scheme for three reasons. First reason is to provide a straightforward method for electrical isolation of the interface; secondly to provide ability to reduce the mass and bend radius of the SpaceWire cable; and thirdly to provide a means for a common physical layer over which multiple spacecraft onboard data link protocols could operate for a wide range of data rates. The intent is to accomplish these goals without significant change to existing SpaceWire design investments. The ability to optionally use Manchester coding in place of the current Data Strobe coding provides the ability to DC balanced the signal transitions unlike the SpaceWire Data Strobe coding; and therefore the ability to isolate the electrical interface without concern. Additionally, because the Manchester code has the clock and data encoded on the same signal, the number of wires of the existing SpaceWire cable could be optionally reduced by 50. This reduction could be an important consideration for many users of SpaceWire as indicated by the already existing effort underway by the SpaceWire working group to reduce the cable mass and bend radius by elimination of shields. However, reducing the signal count by half would provide even greater gains. It is proposed to restrict the data rate for the optional Manchester coding to a fixed data rate of 10 Megabits per second (Mbps) in order to make the necessary changes simple and still able to run in current radiation tolerant Field Programmable Gate Arrays (FPGAs). Even with this constraint, 10 Mbps will meet many applications where SpaceWire is used. These include command and control applications and many instruments applications with have moderate data rate. For most NASA flight implementations, SpaceWire designs are in rad-tolerant FPGAs, and the desire to preserve the heritage design investment is important for cost and risk considerations. The

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

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)

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.

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

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)

Fallback level concepts for conventional and by-wire automotive brake systems

International Nuclear Information System (INIS)

Retzer, H; Mishra, R; Ball, A; Schmidt, K

2012-01-01

Brake-by-wire represents the replacement of traditional brake components such as pumps, hoses, fluids, brake boosters, and master cylinders by electronic sensors and actuators. The different design of these brake concepts poses new challenges for the automotive industry with regard to availability and fallback levels in comparison to standard conventional brake systems. This contribution focuses on the development of appropriate fallback level concepts. Hardware-in-the-loop (HIL) techniques and field trials will be used to investigate the performance and the usability of such systems.

Fallback level concepts for conventional and by-wire automotive brake systems

Science.gov (United States)

Retzer, H.; Mishra, R.; Ball, A.; Schmidt, K.

2012-05-01

Brake-by-wire represents the replacement of traditional brake components such as pumps, hoses, fluids, brake boosters, and master cylinders by electronic sensors and actuators. The different design of these brake concepts poses new challenges for the automotive industry with regard to availability and fallback levels in comparison to standard conventional brake systems. This contribution focuses on the development of appropriate fallback level concepts. Hardware-in-the-loop (HIL) techniques and field trials will be used to investigate the performance and the usability of such systems.

Development of a Flow-Through SQUID System for Non-Destructive Evaluation of MRI Wire

National Research Council Canada - National Science Library

Wellstood, Frederick C

2007-01-01

...) superconducting quantum interference device (SQUID) system. The ability to detect small defects in km-long sections of NbTi magnet wire could improve the production yield of high-field magnets for power and medical applications...

Get Mobile – The Smartphone Brain Scanner

DEFF Research Database (Denmark)

Stahlhut, Carsten; Stopczynski, Arkadiusz; Petersen, Michael Kai

This demonstration will provide live-interaction with a smartphone brain scanner consisting of a low-cost wireless 14-channel EEG headset (Emotiv Epoc) and a mobile device. With our system it is possible to perform real-time functional brain imaging on a smartphone device, including stimulus...

A dedicated breast-PET/CT scanner: Evaluation of basic performance characteristics.

Science.gov (United States)

Raylman, Raymond R; Van Kampen, Will; Stolin, Alexander V; Gong, Wenbo; Jaliparthi, Gangadhar; Martone, Peter F; Smith, Mark F; Sarment, David; Clinthorne, Neal H; Perna, Mark

2018-04-01

Application of advanced imaging techniques, such as PET and x ray CT, can potentially improve detection of breast cancer. Unfortunately, both modalities have challenges in the detection of some lesions. The combination of the two techniques, however, could potentially lead to an overall improvement in diagnostic breast imaging. The purpose of this investigation is to test the basic performance of a new dedicated breast-PET/CT. The PET component consists of a rotating pair of detectors. Its performance was evaluated using the NEMA NU4-2008 protocols. The CT component utilizes a pulsed x ray source and flat panel detector mounted on the same gantry as the PET scanner. Its performance was assessed using specialized phantoms. The radiation dose to a breast during CT imaging was explored by the measurement of free-in-air kerma and air kerma measured at the center of a 16 cm-diameter PMMA cylinder. Finally, the combined capabilities of the system were demonstrated by imaging of a micro-hot-rod phantom. Overall, performance of the PET component is comparable to many pre-clinical and other dedicated breast-PET scanners. Its spatial resolution is 2.2 mm, 5 mm from the center of the scanner using images created with the single-sliced-filtered-backprojection algorithm. Peak NECR is 24.6 kcps; peak sensitivity is 1.36%; the scatter fraction is 27%. Spatial resolution of the CT scanner is 1.1 lp/mm at 10% MTF. The free-in-air kerma is 2.33 mGy, while the PMMA-air kerma is 1.24 mGy. Finally, combined imaging of a micro-hot-rod phantom illustrated the potential utility of the dual-modality images produced by the system. The basic performance characteristics of a new dedicated breast-PET/CT scanner are good, demonstrating that its performance is similar to current dedicated PET and CT scanners. The potential value of this system is the capability to produce combined duality-modality images that could improve detection of breast disease. The next stage in development of this system

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.

Converting Existing Copper Wire Firing System to a Fiber Optically Controlled Firing System for Electromagnetic Pulsed Power Experiments

Science.gov (United States)

2017-12-19

Pulsed Power Experiments by Robert Borys Jr Weapons and Materials Research Directorate, ARL Colby Adams Bowhead Total Enterprise Solutions...ARL-TN-0863 ● DEC 2017 US Army Research Laboratory Converting Existing Copper Wire Firing System to a Fiber-Optically Controlled...Firing System for Electromagnetic Pulsed Power Experiments by Robert Borys Jr and Colby Adams Approved for public release

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.

In vivo cellular imaging with microscopes enabled by MEMS scanners

Science.gov (United States)

Ra, Hyejun

High-resolution optical imaging plays an important role in medical diagnosis and biomedical research. Confocal microscopy is a widely used imaging method for obtaining cellular and sub-cellular images of biological tissue in reflectance and fluorescence modes. Its characteristic optical sectioning capability also enables three-dimensional (3-D) image reconstruction. However, its use has mostly been limited to excised tissues due to the requirement of high numerical aperture (NA) lenses for cellular resolution. Microscope miniaturization can enable in vivo imaging to make possible early cancer diagnosis and biological studies in the innate environment. In this dissertation, microscope miniaturization for in vivo cellular imaging is presented. The dual-axes confocal (DAC) architecture overcomes limitations of the conventional single-axis confocal (SAC) architecture to allow for miniaturization with high resolution. A microelectromechanical systems (MEMS) scanner is the central imaging component that is key in miniaturization of the DAC architecture. The design, fabrication, and characterization of the two-dimensional (2-D) MEMS scanner are presented. The gimbaled MEMS scanner is fabricated on a double silicon-on-insulator (SOI) wafer and is actuated by self-aligned vertical electrostatic combdrives. The imaging performance of the MEMS scanner in a DAC configuration is shown in a breadboard microscope setup, where reflectance and fluorescence imaging is demonstrated. Then, the MEMS scanner is integrated into a miniature DAC microscope. The whole imaging system is integrated into a portable unit for research in small animal models of human biology and disease. In vivo 3-D imaging is demonstrated on mouse skin models showing gene transfer and siRNA silencing. The siRNA silencing process is sequentially imaged in one mouse over time.

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,

The Mechatronic System Design Of Ultrasonic Scanner For Inservice Inspection Of Research Reactor

Science.gov (United States)

Handono, Khairul; Kristedjo, K.; Awwaluddin, M.; Shobary, Ihsan

2018-02-01

The mechatronic system design of ultrasonic scanner for inservices inspection of Research Reactor has been conducted. The requirement designed must be reliable operated, safety to personnel and equipments, ease of maintenance and operation, protection of equipment mechanically, interchangeability of equipments and addition of the several model of probe immersion ultrasonic tranducer. In order to achieve the above goals and obtain the desired results, a mechatronic design based on mechanical and electronic practical experiences will be needed. In this paper consist of the mechanical design and the system mechanical movement using stepper motor control. The criteria and the methods of designs of mechanical and electronic equipments of the system have been discussed and investigated. A mechanical and instrumentation control system drawing and requirement of design will be presented as the outcome of the design. The designed of mechanical system is consequently simulated by solidwork software. The intention of the above research is to create solutions in different ways of inservice inspection of integrity of Reactor.

Transparency in nanophotonic quantum wires

Energy Technology Data Exchange (ETDEWEB)

Singh, Mahi R [Department of Physics and Astronomy, University of Western Ontario, London N6A 3K7 (Canada)

2009-03-28

We have studied the quantum optics of a photonic quantum nanowire doped with an ensemble of three-level nanoparticles. The wire is made from two photonic crystals A and B. Crystal A is embedded within crystal B and acts as a photonic nanowire. It is considered that the conduction band of crystal A lies below that of crystal B. As a result, photons are confined in crystal A and are reflected from crystal B. The bound states of the confined photons are calculated using the transfer matrix method. It is found that the number of bound states in the wire depends on the size of the wire and the energy difference between the conduction band extrema of crystals A and B. The absorption coefficient of the system has also been calculated using the Schroedinger equation method. It is considered that the nanoparticles interact with the photonic bound states. Numerical simulations show that when one of the resonance energies lies near the bound state, the system becomes transparent. However, when the resonance energy lies away from the bound state the crystal reverts to an absorbing state. Similarly, when the radius of the dielectric spheres is changed the location of the transparency peak is shifted. This means that the present system can be switched between two states by changing the size of the wire and the transition energy. These findings can be used to make new types of optical devices.

Transparency in nanophotonic quantum wires

International Nuclear Information System (INIS)

Singh, Mahi R

2009-01-01

We have studied the quantum optics of a photonic quantum nanowire doped with an ensemble of three-level nanoparticles. The wire is made from two photonic crystals A and B. Crystal A is embedded within crystal B and acts as a photonic nanowire. It is considered that the conduction band of crystal A lies below that of crystal B. As a result, photons are confined in crystal A and are reflected from crystal B. The bound states of the confined photons are calculated using the transfer matrix method. It is found that the number of bound states in the wire depends on the size of the wire and the energy difference between the conduction band extrema of crystals A and B. The absorption coefficient of the system has also been calculated using the Schroedinger equation method. It is considered that the nanoparticles interact with the photonic bound states. Numerical simulations show that when one of the resonance energies lies near the bound state, the system becomes transparent. However, when the resonance energy lies away from the bound state the crystal reverts to an absorbing state. Similarly, when the radius of the dielectric spheres is changed the location of the transparency peak is shifted. This means that the present system can be switched between two states by changing the size of the wire and the transition energy. These findings can be used to make new types of optical devices.

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

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.

Comparison of the initial orthodontic force systems produced by a new lingual bracket system and a straight-wire appliance.

Science.gov (United States)

Fuck, Lars-Michael; Wiechmann, Dirk; Drescher, Dieter

2005-09-01

Over the last few years, lingual appliances have become an established orthodontic treatment technique. Many studies have concentrated on various esthetic aspects, on laboratory and clinical procedures, and on patient comfort and compliance. The orthodontic force systems of these appliances, however, have not yet been investigated. The aim of this study was thus to determine the forces and moments produced by a new lingual bracket system during the leveling phase of orthodontic treatment and to compare those with the corresponding force system of a labial straight-wire appliance. The intra-oral situation of ten patients undergoing orthodontic treatment was replicated in measurement casts fitted with lingual and labial brackets. Special care was taken to precisely reproduce each patient's interbracket geometry. We measured each tooth's force systems as generated by a leveling arch inserted into the lingual and labial brackets. The resulting force systems of both appliances were found to be quite similar with regard to the magnitude of most force and moment components. Only the first molars were subjected to considerably greater single forces with the lingual appliance. Tipping moments were found to be significantly smaller with the lingual technique, whereas the rotational moments were significantly smaller with the labial appliance. All in all we noted significant differences between the two techniques only in certain areas which upon closer examination were distributed over only a few tooth types. The initial force systems produced by the new lingual bracket system proved to be comparable with those delivered by a conventional straight-wire appliance. The actual levels of forces and moments, however, were found in certain cases to be too heavy with both techniques. We therefore recommend the development of leveling wires producing considerably lighter forces and moments.

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

Tracking with wire chambers at high luminosities

International Nuclear Information System (INIS)

Hanson, G.G.

1989-12-01

Radiation damage and rate limitations impose severe constraints on wire chambers at the SSC. Possible conceptual designs for wire chamber tracking systems that satisfy these constraints are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 11 refs., 10 figs

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)

An assumed mode method and finite element method investigation of the coupled vibration in a flexible-disk rotor system with lacing wires

Energy Technology Data Exchange (ETDEWEB)

Zhou, Shui-Ting; Huang, Hong-Wu [Hunan University, Changsha (China); Chiu, Yi-Jui; Yu, Guo-Fei [Xiamen University of Technology, Xiamen (China); Yang, Chia-Hao [Taipei Chengshih University of Science and Technology, Taipei (China); Jian, Sheng-Rui [I-Shou University, Kaohsiung (China)

2017-02-15

The Assumed mode method (AMM) and Finite element method (FEM) were used. Their results were compared to investigate the coupled shaft-torsion, disk-transverse, and blade-bending vibrations in a flexible-disk rotor system. The blades were grouped with a spring. The flexible-disk rotor system was divided into three modes of coupled vibrations: Shaft-disk-blade, disk-blade, and blade-blade. Two new modes of coupled vibrations were introduced, namely, lacing wires-blade and lacing wires-disk-blade. The patterns of change of the natural frequencies and mode shapes of the system were discussed. The results showed the following: first, mode shapes and natural frequencies varied, and the results of the AMM and FEM differed; second, numerical calculation results showed three influencing factors on natural frequencies, namely, the lacing wire constant, the lacing wire location, and the flexible disk; lastly, the flexible disk could affect the stability of the system as reflected in the effect of the rotational speed.

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.

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.

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...

Structure of gold monoatomic wires connected to two electrodes

Energy Technology Data Exchange (ETDEWEB)

Zoubkoff, Remi [Centre de Recherche en Matiere Condensee et Nanosciences, CNRS, Campus de Luminy, Case 913, 13288 Marseille Cedex 9 (France)]. E-mail: zoubkoff@crmcn.univ-mrs.fr; Vega, L. de la [Departamento de Fisica de la Materia Condensada C-V, Facultad de Ciencias, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Martin-Rodero, A. [Departamento de Fisica de la Materia Condensada C-V, Facultad de Ciencias, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Levy Yeyati, A. [Departamento de Fisica de la Materia Condensada C-V, Facultad de Ciencias, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Saul, Andres [Centre de Recherche en Matiere Condensee et Nanosciences, CNRS, Campus de Luminy, Case 913, 13288 Marseille Cedex 9 (France)

2007-09-01

In this work, we present calculations concerning the stability of infinite monoatomic Au wires and finite Au wires between electrodes. For the systems with the electrodes, that we represent by FCC slabs with (0 0 1) surfaces, the total energy calculations have been performed with a spd non-orthogonal tight-binding Hamiltonian. For the infinite wires, the calculations were also compared to semi-empirical and first principle ones. For the infinite wires and small enough inter-atomic distances, we find that a zig-zag structure is most stable than the linear one, in agreement with previous calculations. For the system between electrodes, one gets an almost concave or a symmetric broken edges structure depending on the inter-atomic distance.

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.

Electronic brakes. From ABS to brake-by-wire. 2. ed.; Elektronische Bremssysteme. Vom ABS zum Brake-by-Wire

Energy Technology Data Exchange (ETDEWEB)

Reichel, H.R.

2003-07-01

The book reports trends in vehicle brakes from 1968 to 1998. This was the age of the electronic revolution. The book presents conventional brakes, antiblocking systems (ABS), antislip systems (ASS), brake assistants (BAS), dynamic control systems, and brake-by-wire systems. [German] Das Buch berichtet ueber Entwicklungen an Fahrzeugbremsanlagen in der Zeitspanne von 1968 bis etwa 1998. Diese Zeit war gepraegt vom Vordringen der Elektronik in die Bremsen, was fuer Hersteller und Kunden eine Revolution bedeutete. Behandelt sind: (a) Konventionelle Bremsanlagen, (b) Antiblockiersysteme (ABS), (c) Anti-Schlupf-regelungen (ASR), (d) Bremsassistenten (BAS), (e) Fahrdynamikregelungen (FDR, ESP), (f) Brake-by-Wire (orig.)

A stereotaxic frame and computer software for use with CT body scanners

International Nuclear Information System (INIS)

Brown, R.A.; Roberts, T.S.

1979-01-01

A prototype stereotaxic frame for use in conjunction with CT body scanners has been developed and is illustrated. Such a frame may be rigidly attached to the patient's cranium prior to CT scanning and kept attached until completion of the stereotaxic procedure. The frame produces landmarks in each CT slice which allow the CT scanner computer to calculate the spatial orientation of the slice with respect to the frame. Thus the computer may transfer information from the CT slice coordinate system to the frame coordinate system. Using this type of stereotaxic frame it is possible to complete the stereotaxic procedure either in the CT scanner or in the neurosurgery operating suite. In a series of 20 experiments with a target phantom the tip of the probe was placed at a target point with a mean error of 2.0 millimeters. (Auth.)

Computer-aided diagnosis of pneumoconiosis abnormalities extracted from chest radiographs scanned with a CCD scanner

International Nuclear Information System (INIS)

Abe, Koji; Minami, Masahide; Nakamura, Munehiro

2011-01-01

This paper presents a computer-aided diagnosis for pneumoconiosis radiographs obtained with a common charge-coupled devices (CCD) scanner. Since the current computer-aided diagnosis systems of pneumoconiosis are not practical for medical doctors due to high costs of usage for a special scanner, we propose a novel system which measures abnormalities of pneumoconiosis from lung images obtained with a common CCD scanner. Experimental results of discriminations between normal and abnormal cases for 56 right-lung images including 6 standard pneumoconiosis images have shown that the proposed abnormalities are well extracted according to the standards of pneumoconiosis categories. (author)

A hybrid DGTD scheme for transient analysis of electromagnetic field interactions on microwave systems loaded with thin wires

KAUST Repository

Li, Ping

2015-10-15

Use of the discontinuous Galerkin time-domain (DGTD) method for analyzing electromagnetic field interactions on microwave structures loaded with thin wires has been very limited despite its well-known advantages. Direct application of the three dimensional (3D) DGTD method to such structures calls for very fine volumetric discretizations in the proximity of the thin wires. In this work, to avoid this possible source of computational inefficiency, electromagnetic field interactions on thin wires and the rest of the structures are modeled separately using the modified telegrapher and Maxwell equations, respectively. Then, 1D and 3D DGTD methods are used to discretize them. The coupling between the two resulting matrix systems is realized by introducing equivalent source terms in each equation set. A weighted electric field obtained from the 3D discretization around the wire is introduced as a voltage source in the telegrapher equations. A volume current density obtained from the 1D discretization on the wire is introduced as a current source in the Ampere law equation. © 2015 IEEE.

Design of Two Feeder Three Phase Four Wire Distribution System Utilizing Multi Converter UPQC with Fuzzy Logic Controller

Directory of Open Access Journals (Sweden)

Chandra Babu Paduchuri

2014-01-01

Full Text Available This paper proposes the instantaneous p-q theory based fuzzy logic controller (FLC for multi converter unified power quality conditioner (MC-UPQC to mitigate power quality issues in two feeders three-phase four-wire distribution systems. The proposed system is extended system of the existing one feeder three-phase four-wire distribution system, which is operated with UPQC. This system is employed with three voltage source converters, which are connected commonly to two feeder distribution systems. The performance of this proposed system used to compensate voltage sag, neutral current mitigation and compensation of voltage and current harmonics under linear and nonlinear load conditions. The neutral current flowing in series transformers is zero in the implementation of the proposed system. The simulation performance analysis is carried out using MATLAB.

Fabrication and installment of hard-wired I and C works for the neutral beam injection system of the KSTAR project

International Nuclear Information System (INIS)

Jung, Ki Sok; Oh, Byung Hun; In, Sang Ryul; Yoon, Jae Sung

2004-01-01

Instrumentation and Control(I and C) of the neutral beam injection(NBI) system for the K-STAR national fusion research project has been working from the start of the project to answer diverse requests arising from various facets of the development and construction phases of the project. In a parallel effort with the software oriented I and C development, there has been existing an enormous amount of hard-wiring I and C works for the NBI facility to be developed and fabricated in schedule. Circuits and hardwired functions have been designed, tested, fabricated, and finally installed to the relevant parts of the system. Some examples of those hard-wired I and C works are related to the vacuum system, gas feeding system, arc detector circuit, ion source monitoring, bending magnet and calorimeter. They are one of those integral parts for the proper operation of the NBI system. Examples of those hard-wired I and C works are introduced in this presentation

Tracking with wire chambers at the SSC

International Nuclear Information System (INIS)

Hanson, G.G.; Gundy, M.C.; Palounek, A.P.T.

1989-07-01

Limitations placed on wire chambers by radiation damage and rate requirements in the SSC environment are reviewed. Possible conceptual designs for wire chamber tacking systems that meet these requirements are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 13 refs., 11 fig., 1 tab

Digital Data Matrix Scanner Developnent At Marshall Space Flight Center

Science.gov (United States)

2004-01-01

Research at NASA's Marshall Space Flight Center has resulted in a system for reading hidden identification codes using a hand-held magnetic scanner. It's an invention that could help businesses improve inventory management, enhance safety, improve security, and aid in recall efforts if defects are discovered. Two-dimensional Data Matrix symbols consisting of letters and numbers permanently etched on items for identification and resembling a small checkerboard pattern are more efficient and reliable than traditional bar codes, and can store up to 100 times more information. A team led by Fred Schramm of the Marshall Center's Technology Transfer Department, in partnership with PRI,Torrance, California, has developed a hand-held device that can read this special type of coded symbols, even if covered by up to six layers of paint. Before this new technology was available, matrix symbols were read with optical scanners, and only if the codes were visible. This latest improvement in digital Data Matrix technologies offers greater flexibility for businesses and industries already using the marking system. Paint, inks, and pastes containing magnetic properties are applied in matrix symbol patterns to objects with two-dimensional codes, and the codes are read by a magnetic scanner, even after being covered with paint or other coatings. The ability to read hidden matrix symbols promises a wide range of benefits in a number of fields, including airlines, electronics, healthcare, and the automotive industry. Many industries would like to hide information on a part, so it can be read only by the party who put it there. For instance, the automotive industry uses direct parts marking for inventory control, but for aesthetic purposes the marks often need to be invisible. Symbols have been applied to a variety of materials, including metal, plastic, glass, paper, fabric and foam, on everything from electronic parts to pharmaceuticals to livestock. The portability of the hand

Research on Handling Stability of Steering-by-wire System

Directory of Open Access Journals (Sweden)

Yuan Ying

2017-01-01

Full Text Available The main function of steer-by-wire (SBW system are improving steering characteristics, security and stability of the vehicle. In this paper, the variable steering ratio of SBW system is analyzed, and the method of steering ratio based on fuzzy control and neural network are researched. In order to solve the actual working condition, the wheel angle may not reach the expected value, this paper establishes a twodegree-of-freedom (2-DOF vehicle model, and a Matlab/Simulink simulation model, in which a control strategy based on PID controller is put forward to control the front wheel steering angle. Simulation results show that proposed control strategy based on fuzzy neural network can effectively reduce lateral deviation and improve the handling stability and comfortability of the vehicle.

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...

Scanner component and head development for confocal microscopy using moving mirror technology

Science.gov (United States)

Loney, Gregory C.

1993-12-01

One of the challenges in designing a confocal microscope is choosing the scan system configuration. The selection is based largely on the microscope application and involves a few distinct schemes. One scheme, moving mirror using galvanometer and resonant scanners, has been shown to offer an excellent solution exhibited by the large number of commercial systems which utilize them. Perceived shortcomings, such as slow image acquisition, are being dispelled due to the advent of large angle, high frequency resonant scanners. These newer devices offer near video rate performance at good scan efficiency.

Monitoring of debris flows and landslides by wired and wireless systems. Experiences from the Catalan Pyrenees.

Science.gov (United States)

Hürlimann, Marcel; Abancó, Clàudia; Moya, José; Vilajosana, Ignasi; Llosa, Jordi

2013-04-01

Sophisticated monitoring of landslides for research purpose has started in the 1990thies in the Catalan Pyrenees. Since then several types of mass movements (large landslides, debris flows, shallow landslides and rock falls) and multiples techniques have been applied. In this contribution, special attention will be given to the debris-flow monitoring system installed since summer 2009 in the Rebaixader catchment, Central Pyrenees. The monitoring system has continuously been improved during the last years and nowadays includes devices studying the three major aspects: 1) initiation, 2) flow dynamics, and 3) accumulation. While some parts of the monitoring network include a traditional wired system, the newer parts were installed using low-power wireless devices. Two major aspects will be discussed. First, results of the Rebaixader monitoring site will be presented. Second, experience regarding the monitoring will be evaluated focussing on technical aspects and the comparison between wired and wireless techniques. In the Rebaixader catchment, 6 debris flows and 11 debris floods were observed between August 2009 and October 2012. Surprisingly, also 4 major rock falls were recorded. The rainfall analysis shows that the debris flows were triggered by short, high-intensity rainstorms with a preliminary threshold of about 15 mm during 1 hour. In addition, there was observed a positive trend between event volume and rainfall amount or intensity. The analysis of the ground vibration signals shows significant differences between the time series recorded at the different geophones. These differences are associated with the geophone location in the channel (distance and material), the mounting or the data acquisition system. For instance, the most downstream geophone, installed in bedrock, shows the clearest debris-flows vibration time series, while the uppermost is the most reliable regarding the detection of rockfalls. An evaluation of wired versus wireless monitoring

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.

Aircraft scanner data availability via the version 0 Information Management System

Science.gov (United States)

Mah, G. R.

1995-01-01

As part of the Earth Observing System Data and Information System (EOSDIS) development, NASA and other government agencies have developed an operational prototype of the Information Management System (IMS). The IMS provides access to the data archived at the Distributed Active Archive Centers (DAAC's) that allows users to search through metadata describing the (image) data. Criteria based on sensor name or type, date and time, and geographic location are used to search the archive. Graphical representations of coverage and browse images are available to further refine a user's selection. previously, the EROS Data Center (EDC) DAAC had identified the Advanced SOlid-state Array Spectrometer (ASAS), Airborne Visible and infrared Imaging Spectrometer (AVIRIS), NS-001, and Thermal Infrared Multispectral Scanner (TIMS) as precursor data sets similar to those the DAAC will handle in the Earth Observing System era. Currently, the EDC DAAC staff, in cooperation with NASA, has transcribed TIMS, NS-001, and Thematic Mapper Simulation (TMS) data from Ames Research Center and also TIMS data from Stennis Space Center. During the transcription process, the IMS metadata and browse images were created to populate the inventory at the EDC DAAC. These data sets are now available in the IMS and may be requested from the any of the DAAC's via the IMS.

NASA requirements and applications environments for electrical power wiring

International Nuclear Information System (INIS)

Stavnes, M.W.; Hammond, A.N.

1992-01-01

Serious problems can occur from insulation failures in the wiring harnesses of aerospace vehicles. In most recorded incidents, the failures have been identified to be the result of arc tracking, the propagation of an arc along wiring bundles through degradation of insulation. Propagation of the arc can lead to the loss of the entire wiring harness and the functions which it supports. While an extensive database of testing for arc track resistant wire insulations have been developed for aircraft applications, the counterpart requirements for spacecraft are very limited. This paper presents the electrical, thermal, mechanical, chemical, and operational requirements for specification and testing of candidate wiring systems for spacecraft applications

Time synchronization of a wired sensor network for structural health monitoring

International Nuclear Information System (INIS)

Ishikawa, Ken-ichiro; Mita, Akira

2008-01-01

This paper introduces a time synchronization system for wired smart sensor networks to be applied to the structural health monitoring of gigantic structures. The jitter of sensor nodes in the wired network depends on the wire length between the origin and the destination of the time synchronization signals. The proposed system can theoretically achieve the accuracy to limit the jitter of sensors within 34 ns by adjusting the timing depending on the wire length, and experimentally showed the jitter of 190 m separation to be within 25 ns. The proposed system uses local area network (LAN) cables and does not require additional cabling for synchronization. Thus the proposed synchronization system can be embedded in the sensor network with minimal cost

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.

Wire winding increases lifetime of oxide coated cathodes

Science.gov (United States)

Kerslake, W.; Vargo, D.

1965-01-01

Refractory-metal heater base wound with a thin refractory metal wire increases the longevity of oxide-coated cathodes. The wire-wound unit is impregnated with the required thickness of metal oxide. This cathode is useful in magnetohydrodynamic systems and in electron tubes.

Room temperature mushrooming of gallium wires and its growth mechanism

Energy Technology Data Exchange (ETDEWEB)

Zhang, P.; Shen, L.W.; Ouyang, J.; Zhang, Y.M.; Wu, S.Q. [School of Materials Science and Engineering, Southeast University, Nanjing 211189, Jiangsu (China); Sun, Z.M., E-mail: sunzhengming@gmail.com [School of Materials Science and Engineering, Southeast University, Nanjing 211189, Jiangsu (China); National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8569 (Japan)

2015-01-15

Highlights: • Fast spontaneous growth of Ga wires (∼200 nm/s) from a composite system of Cr{sub 2}GaC–Ga is reported. • The fact that Ga wires’ growth phenomena on the composite share most features with metals whiskers with metal/alloy substrates suggests the same mechanism highly likely operating with both systems. • Compelling evidences indicate that the popular stress-based mechanism developed in metal/alloy systems does not hold water in the Cr{sub 2}GaC–Ga composite system. • A new catalysis mechanism is proposed, in which the cleavage planes of Cr{sub 2}GaC grains act as a catalyst for the Ga wires growth. • The new findings in this composite system would lead a new route to address this old problem, and it might see significance in the electronics industry. On the other hand, it is likely to be harnessed to engineer a promising and facile route to prepare various metal wires in large scale. - Abstract: Spontaneous growth of Ga wires at high rate (∼200 nm/s) from a composite system of Cr{sub 2}GaC (a MAX phase) and Ga is presented. A Ga wire growth mechanism based on a catalysis model, which involves fractured Cr{sub 2}GaC grains as the catalyst, is proposed. Regarding the morphologies and the incubation time of the Ga wires, this system shares most features with metal/alloy substrates, such as tin and zinc, where the whiskering phenomenon has been well established and has resisted interpretation for 60+ years. The same growth mechanism is thus considered to operate across different substrates, including the composite one in this study. However, the experimental findings in this composite system oppose the popular stress-based mechanism for the whisker growth with metal/alloy substrates, and provide new sights on this phenomenon. In addition, compelling evidences strongly indicate that fractured Cr{sub 2}GaC grains produced by ball milling initiated the growth of Ga wires, like a ‘catalyst’, and the pristine Cr{sub 2}GaC grains do not

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

Comparison, with regard to safety, between a hard-wired reactor protection system and a computerized protection system. Pt. 1

International Nuclear Information System (INIS)

Buettner, W.E.

1976-07-01

The study compares a conventional hard-wired dynamic reactor protection system with a computerized protection system. In the comparison, only the unequivocally safety-oriented protection actions are considered. In the first part, the different structures of both systems and the method of verification for their functional safety will be described. In the second part, the mean unavailability in case of demand for both systems under defined conditions will be determined. (orig.) [de

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 reliability analysis tool for SpaceWire network

Science.gov (United States)

Zhou, Qiang; Zhu, Longjiang; Fei, Haidong; Wang, Xingyou

2017-04-01

A SpaceWire is a standard for on-board satellite networks as the basis for future data-handling architectures. It is becoming more and more popular in space applications due to its technical advantages, including reliability, low power and fault protection, etc. High reliability is the vital issue for spacecraft. Therefore, it is very important to analyze and improve the reliability performance of the SpaceWire network. This paper deals with the problem of reliability modeling and analysis with SpaceWire network. According to the function division of distributed network, a reliability analysis method based on a task is proposed, the reliability analysis of every task can lead to the system reliability matrix, the reliability result of the network system can be deduced by integrating these entire reliability indexes in the matrix. With the method, we develop a reliability analysis tool for SpaceWire Network based on VC, where the computation schemes for reliability matrix and the multi-path-task reliability are also implemented. By using this tool, we analyze several cases on typical architectures. And the analytic results indicate that redundancy architecture has better reliability performance than basic one. In practical, the dual redundancy scheme has been adopted for some key unit, to improve the reliability index of the system or task. Finally, this reliability analysis tool will has a directive influence on both task division and topology selection in the phase of SpaceWire network system design.

Evaluation of PET Scanner Performance in PET/MR and PET/CT Systems: NEMA Tests.

Science.gov (United States)

Demir, Mustafa; Toklu, Türkay; Abuqbeitah, Mohammad; Çetin, Hüseyin; Sezgin, H Sezer; Yeyin, Nami; Sönmezoğlu, Kerim

2018-02-01

The aim of the present study was to compare the performance of positron emission tomography (PET) component of PET/computed tomography (CT) with new emerging PET/magnetic resonance (MR) of the same vendor. According to National Electrical Manufacturers Association NU2-07, five separate experimental tests were performed to evaluate the performance of PET scanner of General Electric GE company; SIGNATM model PET/MR and GE Discovery 710 model PET/CT. The main investigated aspects were spatial resolution, sensitivity, scatter fraction, count rate performance, image quality, count loss and random events correction accuracy. The findings of this study demonstrated superior sensitivity (~ 4 folds) of PET scanner in PET/MR compared to PET/CT system. Image quality test exhibited higher contrast in PET/MR (~ 9%) compared with PET/CT. The scatter fraction of PET/MR was 43.4% at noise equivalent count rate (NECR) peak of 218 kcps and the corresponding activity concentration was 17.7 kBq/cc. Whereas the scatter fraction of PET/CT was found as 39.2% at NECR peak of 72 kcps and activity concentration of 24.3 kBq/cc. The percentage error of the random event correction accuracy was 3.4% and 3.1% in PET/MR and PET/CT, respectively. It was concluded that PET/MR system is about 4 times more sensitive than PET/CT, and the contrast of hot lesions in PET/MR was ~ 9% higher than PET/CT. These outcomes also emphasize the possibility to achieve excellent clinical PET images with low administered dose and/or a short acquisition time in PET/MR.

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...

An autonomous robot for de-leafing cucumber plants in a high-wire cultivation system

NARCIS (Netherlands)

Henten, van E.J.; Tuijl, van B.A.J.; Hoogakker, G.J.; Weerd, van der M.J.; Hemming, J.; Kornet, J.G.; Bontsema, J.

2005-01-01

The paper presents an autonomous robot for removing the leaves from cucumber plants grown in a high-wire cultivation system. Leaves at the lower end of the plants are removed because of their reduced vitality, their negligible contribution to canopy photosynthesis and their increased sensitivity for

The Effects of Operational Parameters on a Mono-wire Cutting System: Efficiency in Marble Processing

Science.gov (United States)

Yilmazkaya, Emre; Ozcelik, Yilmaz

2016-02-01

Mono-wire block cutting machines that cut with a diamond wire can be used for squaring natural stone blocks and the slab-cutting process. The efficient use of these machines reduces operating costs by ensuring less diamond wire wear and longer wire life at high speeds. The high investment costs of these machines will lead to their efficient use and reduce production costs by increasing plant efficiency. Therefore, there is a need to investigate the cutting performance parameters of mono-wire cutting machines in terms of rock properties and operating parameters. This study aims to investigate the effects of the wire rotational speed (peripheral speed) and wire descending speed (cutting speed), which are the operating parameters of a mono-wire cutting machine, on unit wear and unit energy, which are the performance parameters in mono-wire cutting. By using the obtained results, cuttability charts for each natural stone were created on the basis of unit wear and unit energy values, cutting optimizations were performed, and the relationships between some physical and mechanical properties of rocks and the optimum cutting parameters obtained as a result of the optimization were investigated.

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.

Robust Object Segmentation Using a Multi-Layer Laser Scanner

Science.gov (United States)

Kim, Beomseong; Choi, Baehoon; Yoo, Minkyun; Kim, Hyunju; Kim, Euntai

2014-01-01

The major problem in an advanced driver assistance system (ADAS) is the proper use of sensor measurements and recognition of the surrounding environment. To this end, there are several types of sensors to consider, one of which is the laser scanner. In this paper, we propose a method to segment the measurement of the surrounding environment as obtained by a multi-layer laser scanner. In the segmentation, a full set of measurements is decomposed into several segments, each representing a single object. Sometimes a ghost is detected due to the ground or fog, and the ghost has to be eliminated to ensure the stability of the system. The proposed method is implemented on a real vehicle, and its performance is tested in a real-world environment. The experiments show that the proposed method demonstrates good performance in many real-life situations. PMID:25356645

Evaluation of radiation leakage of the scanner HCV-mobile of the port of Toamasina and the scanner THSCAN of the station of Soarano Antananarivo

International Nuclear Information System (INIS)

RAZAKARIMANANA, T.

2011-01-01

This work was performed at Madagascar-INSTN in collaboration with the GasyNet Company.In order to improve the use of X-rays scanners for control of containers at the SPAT Toamasina and the Soarano Antananarivo's station, the protection of workers and the public against the harmful effects of the ionizing radiation should be strengthen. According to the results obtained in two scanners (HCV-Mobile and THSCAN), the company GasyNet has a system of radiation protection appropriate, dose rates measured do not exceed the regulation standards.The use of devices for checking a leak radiations and the respect of three means of protection (time, distance, and screen) are the most effective means to protect the workers and public against the harmful effects of ionizing radiation emitted by scanners of x-ray. However, to avoid the incidents and accidents, it is necessary to respect and to apply the standards and the national regulations in force. [fr

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.)

Demonstration: A smartphone 3D functional brain scanner

DEFF Research Database (Denmark)

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

We demonstrate a fully portable 3D real-time functional brain scanner consisting of a wireless 14-channel ‘Neuroheadset‘ (Emotiv EPOC) and a Nokia N900 smartphone. The novelty of our system is the ability to perform real-time functional brain imaging on a smartphone device, including stimulus...

A comparative study of wireless and wired sensors networks for deficit irrigation management

Science.gov (United States)

Torres Sánchez, Roque; Domingo Miguel, Rafael; Valles, Fulgencio Soto; Perez-Pastor, Alejandro; Lopez Riquelme, Juan Antonio; Blanco Montoya, Victor

2016-04-01

In recent years, the including of sensors in the context of agricultural water management, has received an increasing interest for the establishment of irrigation strategies, such as regulated deficit irrigation (RDI). These strategies allow a significant improvement of crop water productivity (marketable yield / water applied), especially in woody orchards. The application of these deficit irrigation strategies, requires the monitoring of variables related to the orchard, with the purpose of achieving an efficiently irrigation management, since it is necessary to know the soil and plant water status to achieve the level of water deficit desired in each phenological stage. These parameters involve the measurements of soil and plant parameters, by using appropriate instrumentation devices. Traditional centralized instrumentation systems include soil matric potential, water content and LVDT sensors which information is stored by dataloggers with a wired connection to the sensors. Nowadays, these wired systems are being replaced by wireless ones due, mainly, to cost savings in wiring and labor. These technologies (WSNs) allow monitoring a wide variety of parameters in orchards with high density of sensors using discrete and autonomous nodes in the trees or soil places where it is necessary, without using wires. In this paper we present a trial in a cherry crop orchard, with different irrigation strategies where both a wireless and a wired system have been deployed with the aim of obtaining the best criteria on how to select the most suitable technology in future agronomic monitoring systems. The first stage of this study includes the deploying of nodes, wires, dataloggers and the installation of the sensors (same for both, wired and wireless systems). This stage was done during the first 15 weeks of the trial. Specifically, 40 MPS6 soil matric potential, 20 Enviroscan water content and 40 (LVDT and band) dendometers were installed in order to cover the experimental

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

Development of Monte Carlo simulations to provide scanner-specific organ dose coefficients for contemporary CT

Science.gov (United States)

Jansen, Jan T. M.; Shrimpton, Paul C.

2016-07-01

The ImPACT (imaging performance assessment of CT scanners) CT patient dosimetry calculator is still used world-wide to estimate organ and effective doses (E) for computed tomography (CT) examinations, although the tool is based on Monte Carlo calculations reflecting practice in the early 1990’s. Subsequent developments in CT scanners, definitions of E, anthropomorphic phantoms, computers and radiation transport codes, have all fuelled an urgent need for updated organ dose conversion factors for contemporary CT. A new system for such simulations has been developed and satisfactorily tested. Benchmark comparisons of normalised organ doses presently derived for three old scanners (General Electric 9800, Philips Tomoscan LX and Siemens Somatom DRH) are within 5% of published values. Moreover, calculated normalised values of CT Dose Index for these scanners are in reasonable agreement (within measurement and computational uncertainties of  ±6% and  ±1%, respectively) with reported standard measurements. Organ dose coefficients calculated for a contemporary CT scanner (Siemens Somatom Sensation 16) demonstrate potential deviations by up to around 30% from the surrogate values presently assumed (through a scanner matching process) when using the ImPACT CT Dosimetry tool for newer scanners. Also, illustrative estimates of E for some typical examinations and a range of anthropomorphic phantoms demonstrate the significant differences (by some 10’s of percent) that can arise when changing from the previously adopted stylised mathematical phantom to the voxel phantoms presently recommended by the International Commission on Radiological Protection (ICRP), and when following the 2007 ICRP recommendations (updated from 1990) concerning tissue weighting factors. Further simulations with the validated dosimetry system will provide updated series of dose coefficients for a wide range of contemporary scanners.

Accuracy and reproducibility of the DAVID SLS-2 scanner in three-dimensional facial imaging

DEFF Research Database (Denmark)

Secher, Jesper Jared; Darvann, Tron Andre; Pinholt, Else Marie

2017-01-01

PURPOSE: A prospective study was performed to test the accuracy and reproducibility of the DAVID-SLS-2 scanner (SLS-2) [DAVID Vision Systems GmbH], compared to the validated 3dMDtrio scanner (3dMD) [3dMD, LLC, Atlanta, GA, USA]. MATERIALS AND METHODS: The accuracy of the SLS-2 was determined thro...

Computerized tomographic x-ray scanner system and gantry assembly

International Nuclear Information System (INIS)

Doyd, D.P.; Lanzara, G.

1991-01-01

This patent describes a scanner assembly. It comprises: a support head, a C-shaped gantry, means for supporting the gantry in the support head for rotating movement, an x-ray source mounted on one side of the gantry for independent movement with respect to a detector array along the gantry, the x-ray source projecting x-rays across the gantry, and a detector array mounted on the other side of a gantry for independent movement with respect to the x-ray source along the gantry, the detector array serving to receive the projected x-rays

A Software Suite for Testing SpaceWire Devices and Networks

Science.gov (United States)

Mills, Stuart; Parkes, Steve

2015-09-01

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. 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. STAR-Dundee’s STAR-System software stack has been designed to meet the needs of engineers designing and developing SpaceWire networks and devices. This paper describes the aims of the software and how those needs were met.

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.

Wiring for the secure storage module for the Plutonium Protection System

International Nuclear Information System (INIS)

Arlowe, H.D.

1979-12-01

The wiring for the SSM is divided into two major subsystems: the logic subsystem and the power subsystem. The logic subsystem uses flat ribbon cables and printed wiring cards for low-level signal distribution. Its primary purpose is to provide communications from the Container Modules (CMs) directly to the microcomputer in the SSM Controller. The power subsystem uses conventional cables and does not generally handle signals of less than 30 volts. The 110V ac power is routed to all equipment in the Electronic Enclosure and to cubicle cooling fans. Wiring for drive power and monitor signals for the carrousel stepper motors, deadbolts, and CM-locking solenoids are provided, as well as for the annuciator status lights and tamper switches

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.

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

Design and evaluation of a low thermal electromotive force guarded scanner for resistance measurements

Science.gov (United States)

Jarrett, Dean G.; Marshall, James A.; Marshall, Thomas A.; Dziuba, Ronald F.

1999-06-01

The design and testing of a low thermal electromotive force guarded scanner, developed to provide completely guarded switching when used with actively guarded resistance bridge networks, is described. The design provides a continuous guard circuit trace on the scanner circuit boards that surrounds the relay contacts and protects the measurement circuit from leakages to ground. Modification to the circuit boards and relays of the guarded scanner are explained. Several tests were developed to evaluate the guarding effectiveness, including isolating sections of the guard circuit to create a potential drop between the main and guard circuits. Calibration of standard resistors using the guarded scanner has shown relative differences less than 1×10-6, 30×10-6, and 150×10-6 for measurements made with and without the guarded scanner at nominal resistances of 1, 10, and 100 GΩ, respectively. The substitution method was used to significantly reduce the relative differences between channels to less than 0.5×10-6, 3×10-6, and 30×10-6 for nominal resistances of 1, 10, and 100 GΩ, respectively. Applications for the guarded scanner in automated direct current measurement systems are presented.

Experimental characterization of the Clear-PEM scanner spectrometric performance

Energy Technology Data Exchange (ETDEWEB)

Bugalho, R; Carrico, B; Ferreira, C S; Frade, M; Ferreira, M; Moura, R; Ortigao, C; Pinheiro, J F; Rodrigues, P; Rolo, I; Silva, J C; Trindade, A; Varela, J [Laboratorio de Instrumentacao e Fisica Experimental de Particulas (LIP), Av. Elias Garcia 14-1, 1000-149 Lisboa (Portugal)], E-mail: frade@lip.pt

2009-10-15

In the framework of the Clear-PEM project for the construction of a high-resolution and high-specificity scanner for breast cancer imaging, a Positron Emission Mammography tomograph has been developed and installed at the Instituto Portugues de Oncologia do Porto hospital. The Clear-PEM scanner is mainly composed by two planar detector heads attached to a robotic arm, trigger/data acquisition electronics system and computing servers. The detector heads hold crystal matrices built from 2 x 2 x 20 mm{sup 3} LYSO:Ce crystals readout by Hamamatsu S8550 APD arrays. The APDs are optically coupled to both ends of the 6144 crystals in order to extract the DOI information for each detected event. Each one of 12288 APD's pixels is read and controlled by Application Specific Integrated Circuits water-cooled by an external cooling unit. The Clear-PEM frontend boards innovative design results in a unprecedented integration of the crystal matrices, APDs and ASICs, making Clear-PEM the PET scanner with the highest number of APD pixels ever integrated so far. In this paper, the scanner's main technical characteristics, calibration strategies and the first spectrometric performance evaluation in a clinical environment are presented. The first commissioning results show 99.7% active channels, which, after calibration, have inter-pixel and absolute gain distributions with dispersions of, respectively, 12.2% and 15.3%, demonstrating that despite the large number of channels, the system is uniform. The mean energy resolution at 511 keV is of 15.9%, with a 8.8% dispersion, and the mean C{sub DOI}{sup -1} is 5.9%/mm, with a 7.8% dispersion. The coincidence time resolution, at 511 keV, for a energy window between 400 and 600 keV, is 5.2 ns FWHM.

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

Financing technical-medical activities. CT scanner example in France (1986)

International Nuclear Information System (INIS)

Meyer, C.; Lefaure, C.; Fagnani, F.

1988-01-01

To analyze the french methods for financing technical-medical activities as CT scanners, and to assess if they can face, or not, the management constraints of such activities a financial simulation has been executed. First, current expenditures are totalized (including depreciations and financial charges) with variations according to the numer of examinations per year. Costs are classified especially according to fixed and variable charges: the weight of fixed charges, especially equipment charges, is the most significant. It's very high in yearly expenditures. Most, that involves a very fast decreasing cost with increasing number of procedures. Second, consequences of such accounts are analyzed: - on private CT scanners, Payed with a charge per examination whatever would be the factor's cost; - on public CT scanners, payed with an annual allowance; in this case charges equal receipts whatever would be the cost for a procedure. Third, a break point is defined; either the annual activity is higher: there would be an excedent; either it is lower: there would be a deficit. Then, those results are reported to CT-scanners activity's data in France (1986). After all, financing systems themselves, are discussed and a few hypothesis to explain those desadjustments between charges and their financing way are suggested [fr

Recent developments in wire chamber tracking at SSC

International Nuclear Information System (INIS)

Ogren, H.

1990-01-01

All of the major SSC proposed detectors use wire chambers in their tracking systems. The feasibility of wire chambers in an SSC detector has now been established by a number of groups planning detectors at SSC. The major advances during the past year in understanding straw tube drift chambers are presented and several innovations in gaseous wire chambers are discussed. The R and D section will concentrate on progress in drift cell design, electronics and signal processing, and engineering aspects of the tracking designs

Impacts of Intelligent Automated Quality Control on a Small Animal APD-Based Digital PET Scanner

Science.gov (United States)

Charest, Jonathan; Beaudoin, Jean-François; Bergeron, Mélanie; Cadorette, Jules; Arpin, Louis; Lecomte, Roger; Brunet, Charles-Antoine; Fontaine, Réjean

2016-10-01

Stable system performance is mandatory to warrant the accuracy and reliability of biological results relying on small animal positron emission tomography (PET) imaging studies. This simple requirement sets the ground for imposing routine quality control (QC) procedures to keep PET scanners at a reliable optimal performance level. However, such procedures can become burdensome to implement for scanner operators, especially taking into account the increasing number of data acquisition channels in newer generation PET scanners. In systems using pixel detectors to achieve enhanced spatial resolution and contrast-to-noise ratio (CNR), the QC workload rapidly increases to unmanageable levels due to the number of independent channels involved. An artificial intelligence based QC system, referred to as Scanner Intelligent Diagnosis for Optimal Performance (SIDOP), was proposed to help reducing the QC workload by performing automatic channel fault detection and diagnosis. SIDOP consists of four high-level modules that employ machine learning methods to perform their tasks: Parameter Extraction, Channel Fault Detection, Fault Prioritization, and Fault Diagnosis. Ultimately, SIDOP submits a prioritized faulty channel list to the operator and proposes actions to correct them. To validate that SIDOP can perform QC procedures adequately, it was deployed on a LabPET™ scanner and multiple performance metrics were extracted. After multiple corrections on sub-optimal scanner settings, a 8.5% (with a 95% confidence interval (CI) of [7.6, 9.3]) improvement in the CNR, a 17.0% (CI: [15.3, 18.7]) decrease of the uniformity percentage standard deviation, and a 6.8% gain in global sensitivity were observed. These results confirm that SIDOP can indeed be of assistance in performing QC procedures and restore performance to optimal figures.

Influence of scanner, powder application, and adjustments on CAD-CAM crown misfit.

Science.gov (United States)

Prudente, Marcel S; Davi, Letícia R; Nabbout, Kemilly O; Prado, Célio J; Pereira, Leandro M; Zancopé, Karla; Neves, Flávio D

2018-03-01

The manufacturers of computer-aided design and computer-aided manufacturing (CAD-CAM) systems emphasize that new technologies can improve the marginal fit of dental crowns. However, data supporting this claim are limited. The purpose of this in vitro study was to investigate the differences among the following fabrication methods on the marginal discrepancy of dental crowns: intraoral optical scanners, powder application, and adjustments of intaglio surface. A single human premolar was fixed on a typodont and prepared to receive crowns prepared by the CEREC CAD-CAM system. Three fabrication techniques were used: digital scans using the CEREC Bluecam scanner with titanium dioxide powder (TDP), digital scans using the CEREC Omnicam scanner without TDP, and digital scans using the Omnicam scanner with TDP. Five experimental groups (n=10) were designated: Bluecam (group B), Bluecam with adjustments (group BA), Omnicam (group O), Omnicam with adjustments (group OA), and Omnicam with TDP (group OP). The specimens were scanned using microcomputed tomography to measure the vertical, horizontal, and internal fit and volumetric 3-dimensional (3D) internal fit values of each luting space. The paired t test was used to evaluate mean marginal fit change after adjustments within the same group. One-way analysis of variance and post hoc tests were used to compare groups B, O, and OP (α=.05). Mean vertical fit values ±standard deviations of group B=29.5 ±13.2 μm; BA=26.9 ±7.7 μm; O=149.4 ±64.4 μm; OA=49.4 ±12.7 μm; and OP=33.0 ±8.3 μm. Adjustments in the intaglio surface and TDP application statistically influenced the vertical fit of group O (POmnicam system had significantly higher vertical discrepancy and volumetric 3D internal fit than those fabricated using the Bluecam scanner with TDP. Adjustments of the intaglio surface improved the vertical fit of crowns made using the Omnicam scanner; however, TDP application before Omnicam scanning improved the vertical fit

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...

A new crystal whole-body scanner for positron emitters

International Nuclear Information System (INIS)

Ostertag, H.; Kuebler, W.; Kubesch, R.; Lorenz, W.J.; Woerner, P.

1980-01-01

A multicrystal whole body scanner for positron emitters has been constructed. The annihilation quanta are measured in two opposing detector banks. Each detector bank consists of 64 NaI crystals of 1.5'' diameter x 3'' length. Directly opposing single detectors are in coincidence. The patient moves linearly between the stationary transverse detector banks. The scanning area of the system is 64 x 192 cm 2 . The spatial resolution is 2 cm at a sampling distance of 1 cm. The sensitivity is 6400 counts/s for a pure positron flood source with 1 μCi/cm 2 . The system is controlled by a microcomputer (DEC LSI-11). The scintigrams are shown on a display. Absolute activities can be calculated by mathematical comparison of consecutive emission and transmission scans. The design of the positron scanner and its capacibilities are described. Experimental and initial clinical results are presented. (author)

The Coude spectrograph and echelle scanner of the 2.7 m telescope at McDonald observatory

Science.gov (United States)

Tull, R. G.

1972-01-01

The design of the Coude spectrograph of the 2.7 m McDonald telescope is discussed. A description is given of the Coude scanner which uses the spectrograph optics, the configuration of the large echelle and the computer scanner control and data systems.

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.

29 CFR 1910.304 - Wiring design and protection.

Science.gov (United States)

2010-07-01

... contacts effectively grounded except for receptacles mounted on portable and vehicle-mounted generators in... types of current (ac or dc) on the same premises shall be of such design that the attachment plugs used... premises wiring shall be grounded as follows: (i) All 3-wire dc systems shall have their neutral conductor...

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

ORIS: the Oak Ridge Imaging System program listings. [Nuclear medicine imaging with rectilinear scanner and gamma camera

Energy Technology Data Exchange (ETDEWEB)

Bell, P. R.; Dougherty, J. M.

1978-04-01

The Oak Ridge Imaging System (ORIS) is a general purpose access, storage, processing and display system for nuclear medicine imaging with rectilinear scanner and gamma camera. This volume contains listings of the PDP-8/E version of ORIS Version 2. The system is designed to run under the Digital Equipment Corporation's OS/8 monitor in 16K or more words of core. System and image file mass storage is on RK8E disk; longer-time image file storage is provided on DECtape. Another version of this program exists for use with the RF08 disk, and a more limited version is for DECtape only. This latter version is intended for non-medical imaging.

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...

Design of a hybrid (wired/wireless) acquisition data system for monitoring of cultural heritage physical parameters in Smart Cities.

Science.gov (United States)

García Diego, Fernando-Juan; Esteban, Borja; Merello, Paloma

2015-03-25

Preventive conservation represents a working method and combination of techniques which helps in determining and controlling the deterioration process of cultural heritage in order to take the necessary actions before it occurs. It is acknowledged as important, both in terms of preserving and also reducing the cost of future conservation measures. Therefore, long-term monitoring of physical parameters influencing cultural heritage is necessary. In the context of Smart Cities, monitoring of cultural heritage is of interest in order to perform future comparative studies and load information into the cloud that will be useful for the conservation of other heritage sites. In this paper the development of an economical and appropriate acquisition data system combining wired and wireless communication, as well as third party hardware for increased versatility, is presented. The device allows monitoring a complex network of points with high sampling frequency, with wired sensors in a 1-wire bus and a wireless centralized system recording data for monitoring of physical parameters, as well as the future possibility of attaching an alarm system or sending data over the Internet. This has been possible with the development of three board's designs and more than 5000 algorithm lines. System tests have shown an adequate system operation.

A PET system based on 2-18FDG production with a low energy electrostatic proton accelerator and a dual headed PET scanner.

Science.gov (United States)

Sandell, A; Ohlsson, T; Erlandsson, K; Hellborg, R; Strand, S E

1992-01-01

We have developed a comparatively inexpensive PET system, based on a rotating scanner with two scintillation camera heads, and a nearby low energy electrostatic proton accelerator for production of short-lived radionuclides. Using a 6 MeV proton beam of 5 microA, and by optimization of the target geometry for the 18O(p,n)18F reaction, 750 MBq of 2-18FDG can be obtained. The PET scanner shows a spatial resolution of 6 mm (FWHM) and a sensitivity of 80 s-1kBq-1ml-1 (3 kcps/microCi/ml). Various corrections are included in the imaging process, to compensate for spatial and temporal response variations in the detector system. Both filtered backprojection and iterative reconstruction methods are employed. Clinical studies have been performed with acquisition times of 30-40 min. The system will be used for clinical experimental research with short- as well as long-lived positron emitters. Also the possibility of true 3D reconstruction is under evaluation.

Clinical acceptance testing and scanner comparison of ultrasound shear wave elastography.

Science.gov (United States)

Long, Zaiyang; Tradup, Donald J; Song, Pengfei; Stekel, Scott F; Chen, Shigao; Glazebrook, Katrina N; Hangiandreou, Nicholas J

2018-03-15

Because of the rapidly growing use of ultrasound shear wave elastography (SWE) in clinical practices, there is a significant need for development of clinical physics performance assessment methods for this technology. This study aims to report two clinical medical physicists' tasks: (a) acceptance testing (AT) of SWE function on ten commercial ultrasound systems for clinical liver application and (b) comparison of SWE measurements of targets across vendors for clinical musculoskeletal application. For AT, ten GE LOGIQ E9 XDclear 2.0 scanners with ten C1-6-D and ten 9L-D transducers were studied using two commercial homogenous phantoms. Five measurements were acquired at two depths for each scanner/transducer pair by two operators. Additional tests were performed to access effects of different coupling media, phantom locations and operators. System deviations were less than 5% of group mean or three times standard deviation; therefore, all systems passed AT. A test protocol was provided based on results that no statistically significant difference was observed between using ultrasound gel and salt water for coupling, among different phantom locations, and that interoperator and intraoperator coefficient of variation was less than 3%. For SWE target measurements, two systems were compared - a Supersonic Aixplorer scanner with a SL10-2 and a SL15-4 transducer, and an abovementioned GE scanner with 9L-D transducer. Two stepped cylinders with diameters of 4.05-10.40 mm were measured both longitudinally and transaxially. Target shear wave speed quantification was performed using an in-house MATLAB program. Using the target shear wave speed deduced from phantom specs as a reference, SL15-4 performed the best at the measured depth. However, it was challenging to reliably measure a 4.05 mm target for either system. The reported test methods and results could provide important information when dealing with SWE-related tasks in the clinical environment. © 2018 The Authors

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.

Initial clinical test of a breast-PET scanner

International Nuclear Information System (INIS)

Raylman, Raymond R.; Koren, Courtney; Schreiman, Judith S.; Majewski, Stan; Marano, Gary D.; Abraham, Jame; Kurian, Sobha; Hazard, Hannah; Filburn, Shannon

2011-01-01

The goal of this initial clinical study was to test a new positron emission/tomography imager and biopsy system (PEM/PET) in a small group of selected subjects to assess its clinical imaging capabilities. Specifically, the main task of this study is to determine whether the new system can successfully be used to produce images of known breast cancer and compare them to those acquired by standard techniques. The PEM/PET system consists of two pairs of rotating radiation detectors located beneath a patient table. The scanner has a spatial resolution of ∼2 mm in all three dimensions. The subjects consisted of five patients diagnosed with locally advanced breast cancer ranging in age from 40 to 55 years old scheduled for pre-treatment, conventional whole body PET imaging with F-18 Fluorodeoxyglucose (FDG). The primary lesions were at least 2 cm in diameter. The images from the PEM/PET system demonstrated that this system is capable of identifying some lesions not visible in standard mammograms. Furthermore, while the relatively large lesions imaged in this study where all visualised by a standard whole body PET/CT scanner, some of the morphology of the tumours (ductal infiltration, for example) was better defined with the PEM/PET system. Significantly, these images were obtained immediately following a standard whole body PET scan. The initial testing of the new PEM/PET system demonstrated that the new system is capable of producing good quality breast-PET images compared standard methods.

Mesoscopic NbSe3 wires

International Nuclear Information System (INIS)

Zant, H.S.J. van der; Kalwij, A.; Mantel, O.C.; Markovic, N.

1999-01-01

We have fabricated wire structures with (sub)micron sizes in the charge-density wave conductor NbSe 3 . Electrical transport measurements include complete mode-locking on Shapiro steps and show that the patterning has not affected the CDW material. Our mesoscopic wires show strong fluctuation and hysteresis effects in the low-temperature current-voltage characteristics, as well as a strong reduction of the phase-slip voltage. This reduction can not be explained with existing models. We suggest that single phase-slip events are responsible for a substantial reduction of the CDW strain in micron-sized systems. (orig.)

SpaceWire- Based Control System Architecture for the Lightweight Advanced Robotic Arm Demonstrator [LARAD

Science.gov (United States)

Rucinski, Marek; Coates, Adam; Montano, Giuseppe; Allouis, Elie; Jameux, David

2015-09-01

The Lightweight Advanced Robotic Arm Demonstrator (LARAD) is a state-of-the-art, two-meter long robotic arm for planetary surface exploration currently being developed by a UK consortium led by Airbus Defence and Space Ltd under contract to the UK Space Agency (CREST-2 programme). LARAD has a modular design, which allows for experimentation with different electronics and control software. The control system architecture includes the on-board computer, control software and firmware, and the communication infrastructure (e.g. data links, switches) connecting on-board computer(s), sensors, actuators and the end-effector. The purpose of the control system is to operate the arm according to pre-defined performance requirements, monitoring its behaviour in real-time and performing safing/recovery actions in case of faults. This paper reports on the results of a recent study about the feasibility of the development and integration of a novel control system architecture for LARAD fully based on the SpaceWire protocol. The current control system architecture is based on the combination of two communication protocols, Ethernet and CAN. The new SpaceWire-based control system will allow for improved monitoring and telecommanding performance thanks to higher communication data rate, allowing for the adoption of advanced control schemes, potentially based on multiple vision sensors, and for the handling of sophisticated end-effectors that require fine control, such as science payloads or robotic hands.

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

An Autonomous Robot for De-leafing Cumcumber Plants grown in a High-wire Cultivation System

NARCIS (Netherlands)

Henten, van E.J.; Tuijl, van B.A.J.; Hoogakker, G.J.; Weerd, van der M.J.; Hemming, J.; Kornet, J.G.; Bontsema, J.

2006-01-01

The paper presents an autonomous robot for removing the leaves from cucumber plants grown in a high-wire cultivation system. Leaves at the lower end of the plants are removed because of their reduced vitality, their negligible contribution to canopy photosynthesis and their increased sensitivity to

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

46 CFR 183.340 - Cable and wiring requirements.

Science.gov (United States)

2010-10-01

... a manner as to avoid chafing and other damage. The use of plastic tie wraps must be limited to... requirements. (a) If individual wires, rather than cable, are used in systems greater than 50 volts, the wire... current carrying capacity for the circuit in which they are used; (2) Be installed in a manner to avoid or...

46 CFR 120.340 - Cable and wiring requirements.

Science.gov (United States)

2010-10-01

... chafing and other damage. The use of plastic tie wraps must be limited to bundling or retention of... wires, rather than cables, are used in systems greater than 50 volts, the wire must be in conduit. (b... for the circuit in which they are used; (2) Be installed in a manner to avoid or reduce interference...

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.

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)

Recent developments with a prototype fan-beam optical CT scanner

Science.gov (United States)

Campbell, W. G.; Jirasek, A.; Wells, D.

2013-06-01

The latest design of a prototype fan-beam optical computed tomography scanner is presented. A new beam creation system consists of a 635 nm laser diode module with variable, DC voltage-controlled beam intensity. A change in scanner alignment allows for the elimination of ring artefacts caused by data corruption that is spaced symmetrically across the detector array. These artefacts, as well as a pair of streaking artefacts caused by flask seams, are removed in sinogram space. A flask registration technique has been developed that allows for accurate, reproducible dosimeter placement. Protocol investigations with gel dosimeters have indicated the importance of: i) proper cooling techniques during gel manufacture, and ii) scanning the dosimeter while it is at room temperature. Latest reconstructions of a normoxic polymer gel dosimeter are presented as an indicator of current system performance.

Recent developments with a prototype fan-beam optical CT scanner

International Nuclear Information System (INIS)

Campbell, W G; Jirasek, A; Wells, D

2013-01-01

The latest design of a prototype fan-beam optical computed tomography scanner is presented. A new beam creation system consists of a 635 nm laser diode module with variable, DC voltage-controlled beam intensity. A change in scanner alignment allows for the elimination of ring artefacts caused by data corruption that is spaced symmetrically across the detector array. These artefacts, as well as a pair of streaking artefacts caused by flask seams, are removed in sinogram space. A flask registration technique has been developed that allows for accurate, reproducible dosimeter placement. Protocol investigations with gel dosimeters have indicated the importance of: i) proper cooling techniques during gel manufacture, and ii) scanning the dosimeter while it is at room temperature. Latest reconstructions of a normoxic polymer gel dosimeter are presented as an indicator of current system performance.

A Realization of Temperature Monitoring System Based on Real-Time Kernel μC/OS and 1-wire Bus

Directory of Open Access Journals (Sweden)

Yanmei Qi

2013-06-01

Full Text Available The traditional temperature monitoring system generally adopt some analog sensors for collecting data and a microcontroller for processing data for the purpose of temperature monitoring. However, this back-fore ground system has the disadvantages that the system has poor real-time property and single function, the amount of sensors is not easy to expand, and the software system has a difficulty in upgrading. Aiming at these disadvantages, the system designed in this paper adopts brand-new hardware and software structures: a digitaltemperature sensor array is connected to 1-wire bus and communicated with a control core through 1-wire bus protocol, thus a great convenience is provided for the expansion of the sensor; a real-time operating system is introduced into the software, an application program capable of realizing various functions runs on the real-time kernel μC/OS-II platform. The application of the real-time kernel also provides a good lower layer interface for the late-stage software upgrading.

Transfissural Route Used for Preoperative Localization of Small Pulmonary Lesions with a Short Hook Wire and Suture System

Energy Technology Data Exchange (ETDEWEB)

Iguchi, Toshihiro, E-mail: iguchi@ba2.so-net.ne.jp; Hiraki, Takao, E-mail: takaoh@tc4.so-net.ne.jp; Gobara, Hideo, E-mail: gobara@cc.okayama-u.ac.jp; Fujiwara, Hiroyasu, E-mail: hirofujiwar@gmail.com; Matsui, Yusuke, E-mail: wckyh140@yahoo.co.jp [Okayama University Medical School, Department of Radiology (Japan); Sugimoto, Seiichiro, E-mail: sei1675sugi@yahoo.co.jp; Toyooka, Shinichi, E-mail: shintoyooka@gmail.com; Oto, Takahiro, E-mail: yellowpeachoto@hotmail.com; Miyoshi, Shinichiro, E-mail: smiyoshi@md.okayama-u.ac.jp [Okayama University Medical School, Department of General Thoracic Surgery (Japan); Kanazawa, Susumu, E-mail: susumu@cc.okayama-u.ac.jp [Okayama University Medical School, Department of Radiology (Japan)

2015-02-15

PurposeWe retrospectively evaluated the results of the transfissural route for preoperative localization with a short hook wire and suture system for video-assisted thoracoscopic surgery (VATS).MethodsEleven patients with 11 tumors underwent CT-guided transfissural placement of a hook wire before VATS. This route was selected for all patients, because the distance between the tumor and interlobar fissure was much shorter than the required distance traversed using the conventional approach. Complications were evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.0.ResultsThe hook wire was successfully placed using the transfissural route in all but one case. Of these ten successful placements, two tumors needed a second puncture for optimal placement, because the CT scan showed that the first hook wire was not properly placed in the lung. In one patient, we did not attempt replacement after the first placement was incorrect. In ten successful procedures, the mean distance traversed in the parenchyma of the unaffected lung lobe was 27.9 mm. The distance between the pleura and placed hook wire was significantly shorter than the estimated distance between the pleura and hook wire using the conventional route (mean 16.3 vs. 40.9 mm; P = 0.0002). Grade 1 adverse events occurred (11 pneumothoraxes and 4 pulmonary hemorrhages). No grade 2 or higher adverse event was observed.ConclusionsThe transfissural route used for preoperative localization before VATS is useful for selected patients because this route may allow for more limited lung parenchyma resection.

Towards a wire-mediated coupling of trapped ions

Science.gov (United States)

Clark, Robert; Lee, Tony; Daniilidis, Nikos; Sankaranarayanan, S.; Häffner, Hartmut

2008-03-01

Most schemes for ion trap quantum computation rely upon the exchange of information between ion-qubits in the same trap region, mediated by their shared vibrational mode. An alternative way to achieve this coupling is via the image charges induced in a conducting wire that connects different traps. This was shown to be theoretically possible by Heinzen and Wineland in 1990, but some important practical questions have remained unaddressed. Among these are how the presence of such a wire modifies the motional frequencies and heating rates of trapped ions. We thus have realized this system as a 1 mm-scale planar segmented rf ion trap combined with an electrically floating gold wire of 25 microns diameter and length 1 cm. This wire is placed close to trapped ions using a set of piezoelectric nanopositioners. We present here experimental measurements of the motional frequencies and heating rates of a single trapped calcium ion as the wire is moved from 3.0 mm to 0.2 mm away from the ion. We discuss the implications of these results for achieving wire-mediated coupling in the present apparatus, as well as in future improved setups.

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

Effect of wire size on maxillary arch force/couple systems for a simulated high canine malocclusion.

Science.gov (United States)

Major, Paul W; Toogood, Roger W; Badawi, Hisham M; Carey, Jason P; Seru, Surbhi

2014-12-01

To better understand the effects of copper nickel titanium (CuNiTi) archwire size on bracket-archwire mechanics through the analysis of force/couple distributions along the maxillary arch. The hypothesis is that wire size is linearly related to the forces and moments produced along the arch. An Orthodontic Simulator was utilized to study a simplified high canine malocclusion. Force/couple distributions produced by passive and elastic ligation using two wire sizes (Damon 0.014 and 0.018 inch) measured with a sample size of 144. The distribution and variation in force/couple loading around the arch is a complicated function of wire size. The use of a thicker wire increases the force/couple magnitudes regardless of ligation method. Owing to the non-linear material behaviour of CuNiTi, this increase is less than would occur based on linear theory as would apply for stainless steel wires. The results demonstrate that an increase in wire size does not result in a proportional increase of applied force/moment. This discrepancy is explained in terms of the non-linear properties of CuNiTi wires. This non-proportional force response in relation to increased wire size warrants careful consideration when selecting wires in a clinical setting. © 2014 British Orthodontic Society.

Retrospective Evaluation of Safety, Efficacy and Risk Factors for Pneumothorax in Simultaneous Localizations of Multiple Pulmonary Nodules Using Hook Wire System.

Science.gov (United States)

Zhong, Yan; Xu, Xiao-Quan; Pan, Xiang-Long; Zhang, Wei; Xu, Hai; Yuan, Mei; Kong, Ling-Yan; Pu, Xue-Hui; Chen, Liang; Yu, Tong-Fu

2017-09-01

To evaluate the safety and efficacy of the hook wire system in the simultaneous localizations for multiple pulmonary nodules (PNs) before video-assisted thoracoscopic surgery (VATS), and to clarify the risk factors for pneumothorax associated with the localization procedure. Between January 2010 and February 2016, 67 patients (147 nodules, Group A) underwent simultaneous localizations for multiple PNs using a hook wire system. The demographic, localization procedure-related information and the occurrence rate of pneumothorax were assessed and compared with a control group (349 patients, 349 nodules, Group B). Multivariate logistic regression analyses were used to determine the risk factors for pneumothorax during the localization procedure. All the 147 nodules were successfully localized. Four (2.7%) hook wires dislodged before VATS procedure, but all these four lesions were successfully resected according to the insertion route of hook wire. Pathological diagnoses were acquired for all 147 nodules. Compared with Group B, Group A demonstrated significantly longer procedure time (p pneumothorax (p = 0.019). Multivariate logistic regression analysis indicated that position change during localization procedure (OR 2.675, p = 0.021) and the nodules located in the ipsilateral lung (OR 9.404, p pneumothorax. Simultaneous localizations for multiple PNs using a hook wire system before VATS procedure were safe and effective. Compared with localization for single PN, simultaneous localizations for multiple PNs were prone to the occurrence of pneumothorax. Position change during localization procedure and the nodules located in the ipsilateral lung were independent risk factors for pneumothorax.

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

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.

Three-dimensional rectilinear scanner

International Nuclear Information System (INIS)

O'Neill, W.J.; Strange, D.R.; Miller, A.

1976-01-01

A rectilinear scanner for detecting radiation in a plurality of channels utilizing a collimator is described. Each of the channels receives information from a different portion of the collimator. Information separately received is separately messaged and later collated to present a common image. The information is processed by apparatus in a data processing system. This system has means for messaging analog signals corresponding to gamma radiation counts and converting such analog signals to digital signals. This system has means interfacing the digital signals into an address register that communicates directly via data busses to core memory of a central processing unit by cycle stealing and deriving clinically significant information by computation on the resultant digital data. This system has means for storing, retrieving, and displaying the resultant digital data and the resultant derivations therefrom collectively. This is done in such a manner as to allow time sequencing of the aforementioned operations such that the aforementioned operations can be interleaved on a real time basis. 13 claims, 44 figures

Internal calibration for equipment AR-2000 radio-TLC imaging scanner

International Nuclear Information System (INIS)

Yayan Tahyan; Enny Lestari; Endang Sarmini; Sri Setiyowati

2013-01-01

Testing quality system ISO / IEC 17025:2008 requires that equipment and software used in testing have to give good precision and accuracy. Internal calibration is needed to assess the precision and accuracy of the testing device. The equipment AR-2000 radio-TLC Imaging Scanner in the field of nuclear medicine used in radiochemical purity testing. Determined with precision by the coefficient of variation (% CV) and accuracy, while the deviation value based on internal calibration of the retention factor value reading three peaks Carbon-standard sources mentioned that the reference 14. Standard value % CV ≤ 15% and ≤ 3 mm deviation value. Internal calibration results show that the tool AR-2000 radio-TLC Imaging Scanner provides precision values with a mean coefficient of variation (% CV) and accuracy gained 3.1% for the peak value of unity deviation of 1.79 mm, 0.39 mm and the second peak of the peak three 0.55 mm. This suggests that AR-2000 radio tool-TLC Imaging Scanner in good condition. (author)

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

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

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...

Tracking simulation and wire chamber requirements for the SSC

International Nuclear Information System (INIS)

Hanson, G.G.; Niczyporuk, B.B.; Palounek, A.P.T.

1988-11-01

Limitations placed on wire chambers by radiation damage and rate requirements in the SSC environment are reviewed. Possible conceptual designs for wire chamber tracking systems which meet these requirements are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 16 refs., 16 figs., 2 tabs

Transient Analysis of Lumped Circuit Networks Loaded Thin Wires By DGTD Method

KAUST Repository

Li, Ping

2016-03-31

With the purpose of avoiding very fine mesh cells in the proximity of a thin wire, the modified telegrapher’s equations (MTEs) are employed to describe the thin wire voltage and current distributions, which consequently results in reduced number of unknowns and augmented Courant-Friedrichs-Lewy (CFL) number. As hyperbolic systems, both the MTEs and the Maxwell’s equations are solved by the discontinuous Galerkin time-domain (DGTD) method. In realistic situations, the thin wires could be either driven or loaded by circuit networks. The thin wire-circuit interface performs as a boundary condition for the thin wire solver, where the thin wire voltage and current used for the incoming flux evaluation involved in the DGTD analyzed MTEs are not available. To obtain this voltage and current, an auxiliary current flowing through the thin wire-circuit interface is introduced at each interface. Corresponding auxiliary equations derived from the invariable property of characteristic variable for hyperbolic systems are developed and solved together with the circuit equations established by the modified nodal analysis (MNA) modality. Furthermore, in order to characterize the field and thin wire interactions, a weighted electric field and a volume current density are added into the MTEs and Maxwell-Ampere’s law equation, respectively. To validate the proposed algorithm, three representative examples are presented.

Transient Analysis of Lumped Circuit Networks Loaded Thin Wires By DGTD Method

KAUST Repository

Li, Ping; Shi, Yifei; Jiang, Li Jun; Bagci, Hakan

2016-01-01

With the purpose of avoiding very fine mesh cells in the proximity of a thin wire, the modified telegrapher’s equations (MTEs) are employed to describe the thin wire voltage and current distributions, which consequently results in reduced number of unknowns and augmented Courant-Friedrichs-Lewy (CFL) number. As hyperbolic systems, both the MTEs and the Maxwell’s equations are solved by the discontinuous Galerkin time-domain (DGTD) method. In realistic situations, the thin wires could be either driven or loaded by circuit networks. The thin wire-circuit interface performs as a boundary condition for the thin wire solver, where the thin wire voltage and current used for the incoming flux evaluation involved in the DGTD analyzed MTEs are not available. To obtain this voltage and current, an auxiliary current flowing through the thin wire-circuit interface is introduced at each interface. Corresponding auxiliary equations derived from the invariable property of characteristic variable for hyperbolic systems are developed and solved together with the circuit equations established by the modified nodal analysis (MNA) modality. Furthermore, in order to characterize the field and thin wire interactions, a weighted electric field and a volume current density are added into the MTEs and Maxwell-Ampere’s law equation, respectively. To validate the proposed algorithm, three representative examples are presented.

An image scanner for real time analysis of spark chamber images

International Nuclear Information System (INIS)

Cesaroni, F.; Penso, G.; Locci, A.M.; Spano, M.A.

1975-01-01

The notes describes the semiautomatic scanning system at LNF for the analysis of spark chamber images. From the projection of the images on the scanner table, the trajectory in the real space is reconstructed

Modelling the Siemens SOMATOM Sensation 64 Multi-Slice CT (MSCT) Scanner

International Nuclear Information System (INIS)

Amin, A T Mohd; Rahni, A A Abd

2017-01-01

Reconstructing large volumetric 3D images with minimal radiation dosage exposure with reduced scanning time has been one of the main objectives in the advancement of CT development. One of its advancement is the introduction of multi-slice arc detector geometry from a cone-beam source in third generation scanners. In solving this complex geometry, apart from the known vast computations in CT image reconstruction due to large CT images, iterative reconstruction methods are preferred compared to analytic methods due to its flexibility in image reconstruction. A scanner of interest that has this type of geometry is the Siemens SOMATOM Sensation 64 Multi-Slice CT (MSCT) Scanner , which has a total of 32 slices with 672 detector elements on each slice. In this paper, the scanner projection is modelled via the intersecting lengths between each ray (exhibited from the source to the detector elements) with the scanned image voxels, which are evaluated using the classical Siddon’s algorithm to generate the system matrix, H . This is a prerequisite to perform various iterative reconstruction methods, which involves solving the inverse problem arising from the linear equation: S = H· I; where S is the projections produced from the image, I. Due to the ‘cone-beam geometry’ along the z -axis, the effective field-of-view (FOV) with voxel dimensions (0.4×0.4×0.4) mm 3 is 512×512×32 voxels. The scanner model is demonstrated by reconstructing an image from simulated projections using the analytic Feldkamp-Davis-Kress (FDK) method against basic iterative image reconstruction methods. (paper)

SU-E-T-70: Commissioning a Multislice CT Scanner for X-Ray CT Polymer Gel Dosimetry

Energy Technology Data Exchange (ETDEWEB)

Johnston, H [University of Victoria, Victoria, BC (Australia); UT Southwestern Medical Center, Dallas, TX (United States); Hilts, M [University of Victoria, Victoria, BC (Australia); BC Cancer Agency, Kelowna, BC (Australia); Jirasek, A [University of Victoria, Victoria, BC (Australia)

2014-06-01

Purpose: To commission a multislice computed tomography (CT) scanner for fast and reliable readout of radiation therapy (RT) dose distributions using CT polymer gel dosimetry (PGD). Methods: Commissioning was performed for a 16-slice CT scanner using images acquired through a 1L cylinder filled with water. Additional images were collected using a single slice machine for comparison purposes. The variability in CT number associated with the anode heel effect was evaluated and used to define a new slice-by-slice background image subtraction technique. Image quality was assessed for the multislice system by comparing image noise and uniformity to that of the single slice machine. The consistency in CT number across slices acquired simultaneously using the multislice detector array was also evaluated. Finally, the variability in CT number due to increasing x-ray tube load was measured for the multislice scanner and compared to the tube load effects observed on the single slice machine. Results: Slice-by-slice background subtraction effectively removes the variability in CT number across images acquired simultaneously using the multislice scanner and is the recommended background subtraction method when using a multislice CT system. Image quality for the multislice machine was found to be comparable to that of the single slice scanner. Further study showed CT number was consistent across image slices acquired simultaneously using the multislice detector array for each detector configuration of the slice thickness examined. In addition, the multislice system was found to eliminate variations in CT number due to increasing x-ray tube load and reduce scanning time by a factor of 4 when compared to imaging a large volume using a single slice scanner. Conclusion: A multislice CT scanner has been commissioning for CT PGD, allowing images of an entire dose distribution to be acquired in a matter of minutes. Funding support provided by the Natural Sciences and Engineering

Global Positioning Radiometric Scanner System. Innovative Technology Summary Report

International Nuclear Information System (INIS)

2001-01-01

The US DOE continually seeks safer and more cost-effective technologies for use in decontamination and decommissioning (D and D) of nuclear facilities. To this end, the Deactivation and Decommissioning Focus Area (DDFA) of the DOE OST sponsors the Large Scale Demonstration and Deployment Projects (LSDDP). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE projects and to others in the D and D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) LSDDP generated a list of statements defining specific needs or problems where improved technology could be incorporated into ongoing D and D tasks. One of the stated needs was for developing technologies that would reduce costs and shorten DDOE/EM--0552DOE/EM--0552 and D schedules by providing radiological characterizations to meet the free-release criteria. The Global Positioning Radiometric Scanner (GPRS system shown in Figure 1) utilizes a detection system; a portable computer, a differential global positioning system (d-gps), and a four wheel drive vehicle. Once the survey data has been collected, a software program called GeoSofttrademark generates a graphical representation of the radiological contamination extent. Baseline technology involves gridding the area and hand surveying each grid. This demonstration investigated the associated costs and the required time to evaluate the radiological characterization data from the GPRS with respect to the baseline technology. The GPRS system performs in-situ, real-time analyses to identify the extent of radiological contamination. Benefits expected from using the new innovative technology (GPRS) include: Reduced labor hours associated with performing the survey; Increased number of survey data points; Reduced

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.

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.)

Design and fabrication of a three-finger prosthetic hand using SMA muscle wires

Science.gov (United States)

Simone, Filomena; York, Alexander; Seelecke, Stefan

2015-03-01

Bio-inspired hand-like gripper systems based on shape memory alloy (SMA) wire actuation have the potential to enable a number of useful applications in, e.g., the biomedical field or industrial assembly systems. The inherent high energy density makes SMA solutions a natural choice for systems with lightweight, low noise and high force requirements, such as hand prostheses or robotic systems in a human/machine environment. The focus of this research is the development, design and realization of a SMA-actuated prosthetic hand prototype with three fingers. The use of thin wires (100 μm diameter) allows for high cooling rates and therefore fast movement of each finger. Grouping several small wires mechanically in parallel allows for high force actuation. To save space and to allow for a direct transmission of the motion to each finger, the SMA wires are attached directly within each finger, across each phalanx. In this way, the contraction of the wires will allow the movement of the fingers without the use of any additional gears. Within each finger, two different bundles of wires are mounted: protagonist ones that create bending movement and the antagonist ones that enable stretching of each phalanx. The resistance change in the SMA wires is measured during actuation, which allows for monitoring of the wire stroke and potentially the gripping force without the use of additional sensors. The hand is built with modern 3D-printing technologies and its performance while grasping objects of different size and shape is experimentally investigated illustrating the usefulness of the actuator concept.

Aquilion ONE / ViSION Edition CT scanner realizing 3D dynamic observation with low-dose scanning

International Nuclear Information System (INIS)

Kazama, Masahiro; Saito, Yasuo

2015-01-01

Computed tomography (CT) scanners have been continuously advancing as essential diagnostic imaging equipment for the diagnosis and treatment of a variety of diseases, including the three major disease classes of cerebrovascular disease, cardiovascular disease, and cancer. Through the development of helical CT scanners and multislice CT scanners, Toshiba Medical Systems Corporation has developed the Aquilion ONE, a CT scanner with a scanning range of up to 160 mm per rotation that can obtain three-dimensional (3D) images of the brain, heart, and other organs in a single rotation. We have now developed the Aquilion ONE / ViSION Edition, a next-generation 320-row multislice CT scanner incorporating the latest technologies that achieves a shorter scanning time and significant reduction in dose compared with conventional products. This product with its low-dose scanning technology will contribute to the practical realization of new diagnosis and treatment modalities employing four-dimensional (4D) data based on 3D dynamic observations through continuous rotations. (author)

Josephson junctions of multiple superconducting wires

Science.gov (United States)

Deb, Oindrila; Sengupta, K.; Sen, Diptiman

2018-05-01

We study the spectrum of Andreev bound states and Josephson currents across a junction of N superconducting wires which may have s - or p -wave pairing symmetries and develop a scattering matrix based formalism which allows us to address transport across such junctions. For N ≥3 , it is well known that Berry curvature terms contribute to the Josephson currents; we chart out situations where such terms can have relatively large effects. For a system of three s -wave or three p -wave superconductors, we provide analytic expressions for the Andreev bound-state energies and study the Josephson currents in response to a constant voltage applied across one of the wires; we find that the integrated transconductance at zero temperature is quantized to integer multiples of 4 e2/h , where e is the electron charge and h =2 π ℏ is Planck's constant. For a sinusoidal current with frequency ω applied across one of the wires in the junction, we find that Shapiro plateaus appear in the time-averaged voltage across that wire for any rational fractional multiple (in contrast to only integer multiples in junctions of two wires) of 2 e /(ℏ ω ) . We also use our formalism to study junctions of two p -wave and one s -wave wires. We find that the corresponding Andreev bound-state energies depend on the spin of the Bogoliubov quasiparticles; this produces a net magnetic moment in such junctions. The time variation of these magnetic moments may be controlled by an external voltage applied across the junction. We discuss experiments which may test our theory.

A Novel Atomic Force Microscope with Multi-Mode Scanner

International Nuclear Information System (INIS)

Qin, Chun; Zhang, Haijun; Xu, Rui; Han, Xu; Wang, Shuying

2016-01-01

A new type of atomic force microscope (AFM) with multi-mode scanner is proposed. The AFM system provides more than four scanning modes using a specially designed scanner with three tube piezoelectric ceramics and three stack piezoelectric ceramics. Sample scanning of small range with high resolution can be realized by using tube piezos, meanwhile, large range scanning can be achieved by stack piezos. Furthermore, the combination with tube piezos and stack piezos not only realizes high-resolution scanning of small samples with large- scale fluctuation structure, but also achieves small range area-selecting scanning. Corresponding experiments are carried out in terms of four different scanning modes showing that the AFM is of reliable stability, high resolution and can be widely applied in the fields of micro/nano-technology. (paper)

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,...

47 CFR 68.213 - Installation of other than “fully protected” non-system simple customer premises wiring.

Science.gov (United States)

2010-10-01

... only to “unprotected” premises wiring used with simple installations of wiring for up to four line residential and business telephone service. More complex installations of wiring for multiple line services... requirements, for installation and maintenance of wiring on the subscriber's side of the demarcation point...

MEMS scanner mirror based system for retina scanning and in eye projection

Science.gov (United States)

Woittennek, Franziska; Knobbe, Jens; Pügner, Tino; Dallmann, Hans-Georg; Schelinski, Uwe; Grüger, Heinrich

2015-02-01

Many applications could benefit from miniaturized systems to scan blood vessels behind the retina in the human eye, so called "retina scanning". This reaches from access control to sophisticated security applications and medical devices. High volume systems for consumer applications require low cost and a user friendly operation. For example this includes no need for removal of glasses and self-adjustment, in turn guidance of focus and point of attraction by simultaneous projection for the user. A new system has been designed based on the well-known resonantly driven 2-d scanner mirror of Fraunhofer IPMS. A combined NIR and VIS laser system illuminates the eye through an eye piece designed for an operating distance allowing the use of glasses and granting sufficient field of view. This usability feature was considered to be more important than highest miniaturization. The modulated VIS laser facilitates the projection of an image directly onto the retina. The backscattered light from the continuous NIR laser contains the information of the blood vessels and is detected by a highly sensitive photo diode. A demonstrational setup has been realized including readout and driving electronics. The laser power was adjusted to an eye-secure level. Additional security features were integrated. Test measurements revealed promising results. In a first demonstration application the detection of biometric pattern of the blood vessels was evaluated for issues authentication in.

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

Liquid nitrogen-cooled diamond-wire concrete cutting. Innovative technology summary report

International Nuclear Information System (INIS)

1998-12-01

Liquid nitrogen-cooled diamond-wire concrete cutting can be used to cut through thick concrete walls, floors, and structures without using water to cool the cutting wire. The diamond wire is cooled with liquid nitrogen in a 0.9-m (3-ft) long by 7.6-cm (3-in.) diameter pipe housing. The nitrogen evaporates, so no contaminated liquid waste is generated. Other than the use of liquid nitrogen, the system is a conventional diamond-wire saw assembly with remote hydraulic controls. Setup of the hydraulic-powered drive wheel and the diamond wire for cutting requires a relatively short period of time using people with minimal training. Concrete dust generated during the cutting is considerable and requires control. The production rate of this improved technology is 0.78 m 2 /hr (8.4 ft 2 /hr). The production rates of traditional (baseline) water-cooled diamond-wire cutting and circular saw cutting technologies are 1.11 m 2 /hr (12 ft 2 /hr), and 0.45 m 2 /hr (4.8 ft 2 /hr), respectively. The liquid nitrogen-cooled system costs 189% more than conventional diamond-wire cutting if contaminated liquid wastes collection, treatment, and disposal are not accounted for with the baseline. The new technology was 310% more costly than a conventional diamond circular saw, under the conditions of this demonstration (no wastewater control). For cutting a 0.9-m x 3.7-m (3-ft x 12-ft) wall, the improved technology costs $17,000, while baseline diamond-wire cutting would cost $9,000 and baseline circular-saw cutting would cost $5,500. The improved system may cost less than the baseline technologies or may be comparable in cost if wastewater control is included

Liquid nitrogen-cooled diamond-wire concrete cutting. Innovative technology summary report

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-01

Liquid nitrogen-cooled diamond-wire concrete cutting can be used to cut through thick concrete walls, floors, and structures without using water to cool the cutting wire. The diamond wire is cooled with liquid nitrogen in a 0.9-m (3-ft) long by 7.6-cm (3-in.) diameter pipe housing. The nitrogen evaporates, so no contaminated liquid waste is generated. Other than the use of liquid nitrogen, the system is a conventional diamond-wire saw assembly with remote hydraulic controls. Setup of the hydraulic-powered drive wheel and the diamond wire for cutting requires a relatively short period of time using people with minimal training. Concrete dust generated during the cutting is considerable and requires control. The production rate of this improved technology is 0.78 m{sup 2}/hr (8.4 ft{sup 2}/hr). The production rates of traditional (baseline) water-cooled diamond-wire cutting and circular saw cutting technologies are 1.11 m{sup 2}/hr (12 ft{sup 2}/hr), and 0.45 m{sup 2}/hr (4.8 ft{sup 2}/hr), respectively. The liquid nitrogen-cooled system costs 189% more than conventional diamond-wire cutting if contaminated liquid wastes collection, treatment, and disposal are not accounted for with the baseline. The new technology was 310% more costly than a conventional diamond circular saw, under the conditions of this demonstration (no wastewater control). For cutting a 0.9-m x 3.7-m (3-ft x 12-ft) wall, the improved technology costs $17,000, while baseline diamond-wire cutting would cost $9,000 and baseline circular-saw cutting would cost $5,500. The improved system may cost less than the baseline technologies or may be comparable in cost if wastewater control is included.

Breakdown dynamics of electrically exploding thin metal wires in vacuum

Science.gov (United States)

Sarkisov, G. S.; Caplinger, J.; Parada, F.; Sotnikov, V. I.

2016-10-01

Using a two-frame intensified charge coupled device (iCCD) imaging system with a 2 ns exposure time, we observed the dynamics of voltage breakdown and corona generation in experiments of fast ns-time exploding fine Ni and stainless-steel (SS) wires in a vacuum. These experiments show that corona generation along the wire surface is subjected to temporal-spatial inhomogeneity. For both metal wires, we observed an initial generation of a bright cathode spot before the ionization of the entire wire length. This cathode spot does not expand with time. For 25.4 μm diameter Ni and SS wire explosions with positive polarity, breakdown starts from the ground anode and propagates to the high voltage cathode with speeds approaching 3500 km/s or approximately one percent of light speed.

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.

Survey of damage to 602 MR scanners after the Great East Japan Earthquake

International Nuclear Information System (INIS)

Nakai, Toshiharu; Yamaguchi-Sekino, Sachiko; Tsuchihashi, Toshio

2013-01-01

An earthquake of 9.0 magnitude, the largest in modern Japanese history, struck east Japan on March 11, 2011. We investigated hazards and observations related to magnetic resonance (MR) scanners in this earthquake to evaluate potential risks and consider further prevention or minimization of damage from and injury of patients in such large earthquakes. The investigation team funded by MHLW sent questionnaires to the 984 facilities with installed MR scanners in the 7 prefectures of east Japan (Iwate, Miyagi, Fukushima, Ibaraki, Chiba, Tokyo, Saitama) and collected 458 responses (46.6%) with information on 602 MR scanners (144 units≤0.5 tesla; 31 one-T units; 371 1.5-T units; and 56 units≥3 T). Significant differences in damage were observed between seismic scale 5 and 6 (χ 2 test, P<0.001 for all items of damage checked). The frequencies of typical damage were displacement of magnets (12.4%), failure of the chiller or air conditioning (9.6%), rapid decrease in liquid helium (8.4%), damage to magnet enclosure and its equipment (7.6%), damage to shielding of the MR scanner room (6.1%), damage to the quench duct (4.5%), breakage of devices anchoring system cabinets (4.4%), damage to the magnet base (3.9%), and flying of metal components (1.5%). Twelve facilities reported flooding by the subsequent tsunami, and quench was confirmed in 19 facilities. No fire damage was reported. It was confirmed that no one was severely injured in MR scanners, and base isolation of the building was very useful in completely preventing damage even at seismic scale 7. In the future, training for evacuation and establishment of a standard protocol for emergency shutdown of MR scanners, onsite checking by MR operators, and emergency power plant equipment to maintain chiller for MR scanners will further ensure MR safety in an earthquake. (author)

Expansion of plasma of electrically exploding single copper wire under 4.5 kA-9.5 kA/wire

International Nuclear Information System (INIS)

Li Yexun; Yang Libing; Sun Chengwei

2003-01-01

The experimental system for electrically exploding single metal wire has been designed and manufactured. Expansion of the dense plasma column formed from an electrically exploding Cu wire of diameter 30 μm has been studied with a high-speed photographer to obtain the time-dependent radius (R-t) curve. The experimental results demonstrate that the mean expansion rate of the dense plasma column is 1.94 μm/ns, 2.6 μm/ns and 3.75 μm/ns according to the peak pulse current 4.5 kA, 7 kA and 9.5 kA respectively. The results can be beneficial to giving a profound understanding of the early stage of wire-array Z-pinch physics and to improvement on their design

Pull-pull position control of dual motor wire rope transmission.

Science.gov (United States)

Guo, Quan; Jiao, Zongxia; Yan, Liang; Yu, Qian; Shang, Yaoxing

2016-08-01

Wire rope transmission is very efficient because of the small total moving object mass. The wire rope could only transmit pulling force. Therefore it has to be kept in a tightened state during transmission; in high speed applications the dynamic performance depends on the rope's stiffness, which can be adjusted by the wire rope tension. To improve the system dynamic performance output, this paper proposes a novel pull-pull method based on dual motors connected by wire ropes, for precise, high speed position control applications. The method can regulate target position and wire rope tension simultaneously. Wire ropes remain in a pre-tightening state at all times, which prevents the influence of elasticity and reduces the position tracking error in the changing direction process. Simulations and experiments were conducted; the results indicate that both position precision and superior dynamic performance can be synchronously achieved. The research is relevant to space craft precision pointing instruments.

B218 Weld Filler Wire Characterization for Al-Li Alloy 2195

Science.gov (United States)

Bjorkman, Gerry; Russell, Carolyn

2000-01-01

NASA Marshall Space Flight Center, Lockheed Martin Space Systems- Michoud Operations, and McCook Metals have developed an aluminum-copper weld filler wire for fusion welding aluminum lithium alloy 2195. The aluminum-copper based weld filler wire has been identified as B218, a McCook Metals designation. B218 is the result of six years of weld filler wire development funded by NASA, Lockheed Martin, and McCook Metals. The filler wire chemistry was developed to produce enhanced 2195 weld and repair weld mechanical properties over the 4043 aluminum-silicon weld filler wire, which is currently used to weld 2195 on the Super Lightweight External Tank for the NASA Space Shuttle Program. An initial characterization was performed consisting of a repair weld evaluation using B218 and 4043 weld filler wires. The testing involved room temperature and cryogenic repair weld tensile testing along with fracture toughness testing. From the testing, B218 weld filler wire produce enhanced repair weld tensile strength, ductility, and fracture properties over 4043. B218 weld filler wire has proved to be a superior weld filler wire for welding aluminum lithium alloy 2195 over 4043.

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.

Note: A silicon-on-insulator microelectromechanical systems probe scanner for on-chip atomic force microscopy

Energy Technology Data Exchange (ETDEWEB)

Fowler, Anthony G.; Maroufi, Mohammad; Moheimani, S. O. Reza, E-mail: Reza.Moheimani@newcastle.edu.au [School of Electrical Engineering and Computer Science, University of Newcastle, Callaghan, NSW 2308 (Australia)

2015-04-15

A new microelectromechanical systems-based 2-degree-of-freedom (DoF) scanner with an integrated cantilever for on-chip atomic force microscopy (AFM) is presented. The silicon cantilever features a layer of piezoelectric material to facilitate its use for tapping mode AFM and enable simultaneous deflection sensing. Electrostatic actuators and electrothermal sensors are used to accurately position the cantilever within the x-y plane. Experimental testing shows that the cantilever is able to be scanned over a 10 μm × 10 μm window and that the cantilever achieves a peak-to-peak deflection greater than 400 nm when excited at its resonance frequency of approximately 62 kHz.

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 rope isolators for vibration isolation of equipment and structures – A review

International Nuclear Information System (INIS)

Balaji, P S; Rahman, M E; Lau, H H; Moussa, Leblouba

2015-01-01

Vibrations and shocks are studied using various techniques and analyzed to predict their detrimental effect on the equipment and structures. In cases, where the effects of vibration become unacceptable, it may cause structural damage and affect the operation of the equipment. Hence, adding a discrete system to isolate the vibration from source becomes necessary. The Wire Rope Isolator (WRI) can be used to effectively isolate the system from disturbing vibrations. The WRI is a type of passive isolator that exhibits nonlinear behavior. It consists of stranded wire rope held between two metal retainer bars and the metal wire rope is made up of individual wire strands that are in frictional contact with each other, hence, it is a kind of friction-type isolator. This paper compiles the research work on wire rope isolators. This paper presents the research work under two categories, namely monotonic and cyclic loading behaviors of WRI. The review also discusses the different terminologies associated with vibration isolation system and highlights the comparison between various isolation systems. (paper)

3D Laser Scanner for Underwater Manipulation.

Science.gov (United States)

Palomer, Albert; Ridao, Pere; Youakim, Dina; Ribas, David; Forest, Josep; Petillot, Yvan

2018-04-04

Nowadays, research in autonomous underwater manipulation has demonstrated simple applications like picking an object from the sea floor, turning a valve or plugging and unplugging a connector. These are fairly simple tasks compared with those already demonstrated by the mobile robotics community, which include, among others, safe arm motion within areas populated with a priori unknown obstacles or the recognition and location of objects based on their 3D model to grasp them. Kinect-like 3D sensors have contributed significantly to the advance of mobile manipulation providing 3D sensing capabilities in real-time at low cost. Unfortunately, the underwater robotics community is lacking a 3D sensor with similar capabilities to provide rich 3D information of the work space. In this paper, we present a new underwater 3D laser scanner and demonstrate its capabilities for underwater manipulation. In order to use this sensor in conjunction with manipulators, a calibration method to find the relative position between the manipulator and the 3D laser scanner is presented. Then, two different advanced underwater manipulation tasks beyond the state of the art are demonstrated using two different manipulation systems. First, an eight Degrees of Freedom (DoF) fixed-base manipulator system is used to demonstrate arm motion within a work space populated with a priori unknown fixed obstacles. Next, an eight DoF free floating Underwater Vehicle-Manipulator System (UVMS) is used to autonomously grasp an object from the bottom of a water tank.

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.

A multispectral scanner survey of the Rocky Flats Environmental Technology Site and surrounding area, Golden, Colorado

International Nuclear Information System (INIS)

Brewster, S.B. Jr.; Brickey, D.W.; Ross, S.L.; Shines, J.E.

1997-04-01

Aerial multispectral scanner imagery was collected of the Rocky Flats Environmental Technology Site in Golden, Colorado, on June 3, 5, 6, and 7, 1994, using a Daedalus AADS1268 multispectral scanner and coincident aerial color and color infrared photography. Flight altitudes were 4,500 feet (1372 meters) above ground level to match prior 1989 survey data; 2,000 feet (609 meters) above ground level for sitewide vegetation mapping; and 1,000 feet (304 meters) above ground level for selected areas of special interest. A multispectral survey was initiated to improve the existing vegetation classification map, to identify seeps and springs, and to generate ARC/INFO Geographic Information System compatible coverages of the vegetation and wetlands for the entire site including the buffer zone. The multispectral scanner imagery and coincident aerial photography were analyzed for the detection, identification, and mapping of vegetation and wetlands. The multispectral scanner data were processed digitally while the color and color infrared photography were manually photo-interpreted to define vegetation and wetlands. Several standard image enhancement techniques were applied to the multispectral scanner data to assist image interpretation. A seep enhancement was applied and a color composite consisting of multispectral scanner channels 11, 7, and 5 (thermal infrared, mid-infrared, and red bands, respectively) proved most useful for detecting seeps, seep zones, and springs. The predawn thermal infrared data were also useful in identifying and locating seeps. The remote sensing data, mapped wetlands, and ancillary Geographic Information System compatible data sets were spatially analyzed for seeps

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!.

Toward a reduced-wire readout system for ultrasound imaging.

Science.gov (United States)

Lim, Jaemyung; Arkan, Evren F; Degertekin, F Levent; Ghovanloo, Maysam

2014-01-01

We present a system-on-a-chip (SoC) for use in high-frequency capacitive micromachined ultrasonic transducer (CMUT) imaging systems. This SoC consists of trans-impedance amplifiers (TIA), delay locked loop (DLL) based clock multiplier, quadrature sampler, and pulse width modulator (PWM). The SoC down converts RF echo signal to baseband by quadrature sampling which facilitates modulation. To send data through a 1.6 m wire in the catheter which has limited bandwidth and is vulnerable to noise, the SoC creates a pseudo-digital PWM signal which can be used for back telemetry or wireless readout of the RF data. In this implementation, using a 0.35-μm std. CMOS process, the TIA and single-to-differential (STD) converter had 45 MHz bandwidth, the quadrature sampler had 10.1 dB conversion gain, and the PWM had 5-bit ENoB. Preliminary results verified front-end functionality, and the power consumption of a TIA, STD, quadrature sampler, PWM, and clock multiplier was 26 mW from a 3 V supply.

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

Introducing measure-by-wire, the systematic use of systems and control theory in transmission electron microscopy

International Nuclear Information System (INIS)

Tejada, Arturo; Dekker, Arnold J. den; Van den Broek, Wouter

2011-01-01

Transmission electron microscopes (TEMs) are the tools of choice for academic and industrial research at the nano-scale. Due to their increasing use for routine, repetitive measurement tasks (e.g., quality control in production lines) there is a clear need for a new generation of high-throughput microscopes designed to autonomously extract information from specimens (e.g., particle size distribution, chemical composition, structural information, etc.). To aid in their development, a new engineering perspective on TEM design, based on principles from systems and control theory, is proposed here: measure-by-wire (not to be confused with remote microscopy). Under this perspective, the TEM operator yields the direct control of the microscope's internal processes to a hierarchy of feedback controllers and high-level supervisors. These make use of dynamical models of the main TEM components together with currently available measurement techniques to automate processes such as defocus correction or specimen displacement. Measure-by-wire is discussed in depth, and its methodology is illustrated through a detailed example: the design of a defocus regulator, a type of feedback controller that is akin to existing autofocus procedures. -- Highlights: ► High-throughput TEM operation is increasingly needed for research and industry. ► Autonomous high-throughput TEMs enabled by systems and control theory. ► Measure-by-wire is a new holistic automation oriented engineering view of TEM. ► A detailed example shows how to apply MBW to the automatic control of defocus.

Note: Reliable and non-contact 6D motion tracking system based on 2D laser scanners for cargo transportation

Energy Technology Data Exchange (ETDEWEB)

Kim, Young-Keun, E-mail: ykkim@handong.edu [Department of Mechanical and Control Engineering, Handong Global University, Pohang (Korea, Republic of); Kim, Kyung-Soo [Department of Mechanical Engineering, KAIST, Daejeon 305-701 (Korea, Republic of)

2014-10-15

Maritime transportation demands an accurate measurement system to track the motion of oscillating container boxes in real time. However, it is a challenge to design a sensor system that can provide both reliable and non-contact methods of 6-DOF motion measurements of a remote object for outdoor applications. In the paper, a sensor system based on two 2D laser scanners is proposed for detecting the relative 6-DOF motion of a crane load in real time. Even without implementing a camera, the proposed system can detect the motion of a remote object using four laser beam points. Because it is a laser-based sensor, the system is expected to be highly robust to sea weather conditions.

Research on Sliding Mode Control for Steer-by-Wire System in Forklift

Directory of Open Access Journals (Sweden)

Huang Jun-Jie

2017-01-01

Full Text Available Aiming at steering stability and wheel angle tracking of steer-by-wire (SBW three wheeled forklift, steering dynamic model and SBW system mathematical model of three wheeled forklift are established. A control strategy for the ideal transmission ratio is introduced based on this model, which ensures forklift steering gain invariant. A sliding mode controller can then be designed based on the bound information of uncertain system parameters, uncertain self-aligning torque, and external disturbances. The results of simulation show the control strategies above can effectively reduce the sideslip angle when the forklift is steering and improve the sensitivity and stability of the steering forklift; at the same time can effectively restrain the parameter perturbation of internal system and external disturbance, which improves the tracking performance of the wheel angle.

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.

Monte Carlo simulation to analyze the cost-benefit of radioactive seed localization versus wire localization for breast-conserving surgery in fee-for-service health care systems compared with accountable care organizations.

Science.gov (United States)

Loving, Vilert A; Edwards, David B; Roche, Kevin T; Steele, Joseph R; Sapareto, Stephen A; Byrum, Stephanie C; Schomer, Donald F

2014-06-01

In breast-conserving surgery for nonpalpable breast cancers, surgical reexcision rates are lower with radioactive seed localization (RSL) than wire localization. We evaluated the cost-benefit of switching from wire localization to RSL in two competing payment systems: a fee-for-service (FFS) system and a bundled payment system, which is typical for accountable care organizations. A Monte Carlo simulation was developed to compare the cost-benefit of RSL and wire localization. Equipment utilization, procedural workflows, and regulatory overhead differentiate the cost between RSL and wire localization. To define a distribution of possible cost scenarios, the simulation randomly varied cost drivers within fixed ranges determined by hospital data, published literature, and expert input. Each scenario was replicated 1000 times using the pseudorandom number generator within Microsoft Excel, and results were analyzed for convergence. In a bundled payment system, RSL reduced total health care cost per patient relative to wire localization by an average of $115, translating into increased facility margin. In an FFS system, RSL reduced total health care cost per patient relative to wire localization by an average of $595 but resulted in decreased facility margin because of fewer surgeries. In a bundled payment system, RSL results in a modest reduction of cost per patient over wire localization and slightly increased margin. A fee-for-service system suffers moderate loss of revenue per patient with RSL, largely due to lower reexcision rates. The fee-for-service system creates a significant financial disincentive for providers to use RSL, although it improves clinical outcomes and reduces total health care costs.

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)

Eliminating a Major Cause of Wire Drawing Breakage in A-15 High-Field Superconductors

International Nuclear Information System (INIS)

Austen, Alfred R.

2003-01-01

Eliminating a Major Cause of Wire Drawing Breakage in A-15 High-Field Superconductors Phase 1 Summary Purpose of the research: The Phase 1 goal was to make a significant improvement in the wire drawing technology used for difficult to draw superconductor precursor composites. Many ductile Nb-Al and Nb-Sn precursor wire composites have experienced the onset of wire drawing breakage at about 1.5 mm diameter. Phase 1 focused on evaluating the role that precision rigid guidance of the wire into the drawing die and the hydrostatic stress state at the die entrance played in preventing wire breakage. Research carried out: The research performed depended upon the construction of both a mechanical wire guide and a hydrostatic pressure stiffened wire guidance system. Innovare constructed the two wire guidance systems and tested them for their ability to reduce wire drawing breakage. One set of hardware provided rigid alignment of the wires to their wire drawing die axes within 0.35 degrees using ''hydrostatic pressure stiffening'' to enable the precision guidance strategy to be implemented for these highly flexible small diameter wires. This apparatus was compared to a guide arrangement that used short span mechanical guide alignment with a misalignment limit of about 0.75 degrees. Four A-15 composite wires with breakage histories were drawn to evaluate the use of these wire guiding systems to reduce and/or eliminate wire breakage. Research findings and results: In Phase 1, a breakthrough in wire drawing technology for A-15 superconductor composites was achieved by dramatically limiting or eliminating breakage in four different A-15 composite precursor wire designs during the drawing of these very desirable composites that previously could not be drawn to near final size. Research results showed that the proposed Phase 1 mechanical wire guides were sufficiently effective and successful in eliminating breakage when used along with other advanced wire drawing technology to

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)