WorldWideScience

Sample records for laser calibration system

  1. A laser calibration system for the STAR TPC

    CERN Document Server

    Lebedev, A

    2002-01-01

    A Time Projection Chamber (TPC) is the primary tracking detector for the STAR experiment at RHIC. A laser calibration system was built to calibrate and monitor the TPC tracking performance. The laser system uses a novel design which produces approx 500 thin, ionizing beams distributed throughout the tracking volume. This new approach is significantly simpler than the traditional ones, and provides complete TPC coverage at a reduced cost. The laser system was used during the RHIC 2000 summer run to measure drift velocities with about 0.02% accuracy and to monitor the TPC performance. Calibration runs were made with and without a magnetic field to check B field map corrections.

  2. Calibration technology in application of robot-laser scanning system

    Science.gov (United States)

    Ren, YongJie; Yin, ShiBin; Zhu, JiGui

    2012-11-01

    A system composed of laser sensor and 6-DOF industrial robot is proposed to obtain complete three-dimensional (3-D) information of the object surface. Suitable for the different combining ways of laser sensor and robot, a new method to calibrate the position and pose between sensor and robot is presented. By using a standard sphere with known radius as a reference tool, the rotation and translation matrices between the laser sensor and robot are computed, respectively in two steps, so that many unstable factors introduced in conventional optimization methods can be avoided. The experimental results show that the accuracy of the proposed calibration method can be achieved up to 0.062 mm. The calibration method is also implemented into the automated robot scanning system to reconstruct a car door panel.

  3. Research on calibration algorithm in laser scanning projection system

    Science.gov (United States)

    Li, Li Juan; Qu, Song; Hou, Mao Sheng

    2017-10-01

    Laser scanning projection technology can project the image defined by the existing CAD digital model to the working surface, in the form of a laser harness profile. This projection is in accordance with the ratio of 1: 1. Through the laser harness contours with high positioning quality, the technical staff can carry out the operation with high precision. In a typical process of the projection, in order to determine the relative positional relationship between the laser projection instrument and the target, it is necessary to place several fixed reference points on the projection target and perform the calibration of projection. This position relationship is the transformation from projection coordinate system to the global coordinate system. The entire projection work is divided into two steps: the first step, the calculation of the projector six position parameters is performed, that is, the projector calibration. In the second step, the deflection angle is calculated by the known projector position parameter and the known coordinate points, and then the actual model is projected. Typically, the calibration requires the establishment of six reference points to reduce the possibility of divergence of the nonlinear equations, but the whole solution is very complex and the solution may still diverge. In this paper, the distance is detected combined with the calculation so that the position parameters of the projector can be solved by using the coordinate values of three reference points and the distance of at least one reference point to the projector. The addition of the distance measurement increases the stability of the solution of the nonlinear system and avoids the problem of divergence of the solution caused by the reference point which is directly under the projector. Through the actual analysis and calculation, the Taylor expansion method combined with the least squares method is used to obtain the solution of the system. Finally, the simulation experiment is

  4. The laser-based calibration system of delta spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Malakhov, A.I. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Anisimov, Yu.S. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Gmuca, S. [Inst. of Physics, SAS, Bratislava (Slovakia); Kizka, V.A. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Kliman, J. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Inst. of Physics, SAS, Bratislava (Slovakia); Krasnov, V.A. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Kurepin, A.B. [Inst. for Nuclear Research RAS, Moscow (Russian Federation); Kuznetsov, S.N. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Livanov, A.N. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Matousek, V. [Inst. of Physics, SAS, Bratislava (Slovakia); Morhac, M. [Inst. of Physics, SAS, Bratislava (Slovakia)]. E-mail: Miroslav.Morhac@savba.sk; Turzo, I. [Inst. of Physics, SAS, Bratislava (Slovakia)

    2006-10-15

    We present a report on a laser calibration system of DELTA spectrometer that has been designed and developed in the Laboratory of High Energies, JINR, Dubna. The system is intended for monitoring and continuous stabilization of the outputs of the detectors of the spectrometer. The UV nitrogen pulse laser along with optical filters, collection of optical fibers and plastic scintillators serving for conversion of UV light pulses to longer wavelength and for diffusion of the light beam to illuminate 300 photomultipliers are used. We stabilize the positions of laser peaks by corrections of high voltages of the corresponding photomultipliers. The proposed system allows one to accomplish the stabilization during the experiment with the use of the same electronics. The control software together with the first results from test runs are described as well.

  5. The Laser Calibration System of the ALICE Time Projection Chamber

    CERN Document Server

    Renault, G; Nielsen, B S; Westergaard, J

    2005-01-01

    A Large Ion Collider Experiment (ALICE) is the only experiment at the Large Hadron Collider (LHC) dedicated to the study of heavy ion collisions. The Time Projection Chamber (TPC) is the main tracking detector covering the pseudo rapidity range $|\\eta|< 0.9$. It is designed for a maximum multiplicity \\dNdy = 8000. The aim of the laser system is to simulate ionizing tracks at predifined positions throughout the drift volume in order to monitor the TPC response to a known source. In particular, the alignment of the read-out chambers will be performed, and variations of the drift velocity due to drift field imperfections can be measured and used as calibration data in the physics data analysis. In this paper we present the design of the pulsed UV laser and optical system, together with the control and monitoring systems.

  6. Laser Tracker Calibration - Testing the Angle Measurement System -

    Energy Technology Data Exchange (ETDEWEB)

    Gassner, Georg; Ruland, Robert; /SLAC

    2008-12-05

    Physics experiments at the SLAC National Accelerator Laboratory (SLAC) usually require high accuracy positioning, e. g. 100 {micro}m over a distance of 150 m or 25 {micro}m in a 10 x 10 x 3 meter volume. Laser tracker measurement systems have become one of the most important tools for achieving these accuracies when mapping components. The accuracy of these measurements is related to the manufacturing tolerances of various individual components, the resolutions of measurement systems, the overall precision of the assembly, and how well imperfections can be modeled. As with theodolites and total stations, one can remove the effects of most assembly and calibration errors by measuring targets in both direct and reverse positions and computing the mean to obtain the result. However, this approach does not compensate for errors originating from the encoder system. In order to improve and gain a better understanding of laser tracker angle measurement tolerances we extended our laboratory's capabilities with the addition of a horizontal angle calibration test stand. This setup is based on the use of a high precision rotary table providing an angular accuracy of better than 0.2 arcsec. Presently, our setup permits only tests of the horizontal angle measurement system. A test stand for vertical angle calibration is under construction. Distance measurements (LECOCQ & FUSS, 2000) are compared to an interferometer bench for distances of up to 32 m. Together both tests provide a better understanding of the instrument and how it should be operated. The observations also provide a reasonable estimate of covariance information of the measurements according to their actual performance for network adjustments.

  7. A new systematic calibration method of ring laser gyroscope inertial navigation system

    Science.gov (United States)

    Wei, Guo; Gao, Chunfeng; Wang, Qi; Wang, Qun; Xiong, Zhenyu; Long, Xingwu

    2016-10-01

    Inertial navigation system has been the core component of both military and civil navigation systems. Before the INS is put into application, it is supposed to be calibrated in the laboratory in order to compensate repeatability error caused by manufacturing. Discrete calibration method cannot fulfill requirements of high-accurate calibration of the mechanically dithered ring laser gyroscope navigation system with shock absorbers. This paper has analyzed theories of error inspiration and separation in detail and presented a new systematic calibration method for ring laser gyroscope inertial navigation system. Error models and equations of calibrated Inertial Measurement Unit are given. Then proper rotation arrangement orders are depicted in order to establish the linear relationships between the change of velocity errors and calibrated parameter errors. Experiments have been set up to compare the systematic errors calculated by filtering calibration result with those obtained by discrete calibration result. The largest position error and velocity error of filtering calibration result are only 0.18 miles and 0.26m/s compared with 2 miles and 1.46m/s of discrete calibration result. These results have validated the new systematic calibration method and proved its importance for optimal design and accuracy improvement of calibration of mechanically dithered ring laser gyroscope inertial navigation system.

  8. Calibration method for a vision guiding-based laser-tracking measurement system

    International Nuclear Information System (INIS)

    Shao, Mingwei; Wei, Zhenzhong; Hu, Mengjie; Zhang, Guangjun

    2015-01-01

    Laser-tracking measurement systems (laser trackers) based on a vision-guiding device are widely used in industrial fields, and their calibration is important. As conventional methods typically have many disadvantages, such as difficult machining of the target and overdependence on the retroreflector, a novel calibration method is presented in this paper. The retroreflector, which is necessary in the normal calibration method, is unnecessary in our approach. As the laser beam is linear, points on the beam can be obtained with the help of a normal planar target. In this way, we can determine the function of a laser beam under the camera coordinate system, while its corresponding function under the laser-tracker coordinate system can be obtained from the encoder of the laser tracker. Clearly, when several groups of functions are confirmed, the rotation matrix can be solved from the direction vectors of the laser beams in different coordinate systems. As the intersection of the laser beams is the origin of the laser-tracker coordinate system, the translation matrix can also be determined. Our proposed method not only achieves the calibration of a single laser-tracking measurement system but also provides a reference for the calibration of a multistation system. Simulations to evaluate the effects of some critical factors were conducted. These simulations show the robustness and accuracy of our method. In real experiments, the root mean square error of the calibration result reached 1.46 mm within a range of 10 m, even though the vision-guiding device focuses on a point approximately 5 m away from the origin of its coordinate system, with a field of view of approximately 200 mm  ×  200 mm. (paper)

  9. Laser Guided Automated Calibrating System for Accurate Bracket ...

    African Journals Online (AJOL)

    Background: The basic premise of preadjusted bracket system is accurate bracket positioning. ... using MATLAB ver. 7 software (The MathWorks Inc.). These images are in the form of matrices of size 640 × 480. 650 nm (red light) type III diode laser is used as ... motion control and Pitch, Yaw, Roll degrees of freedom (DOF).

  10. Review of technological advancements in calibration systems for laser vision correction

    Science.gov (United States)

    Arba-Mosquera, Samuel; Vinciguerra, Paolo; Verma, Shwetabh

    2018-02-01

    Using PubMed and our internal database, we extensively reviewed the literature on the technological advancements in calibration systems, with a motive to present an account of the development history, and latest developments in calibration systems used in refractive surgery laser systems. As a second motive, we explored the clinical impact of the error introduced due to the roughness in ablation and its corresponding effect on system calibration. The inclusion criterion for this review was strict relevance to the clinical questions under research. The existing calibration methods, including various plastic models, are highly affected by various factors involved in refractive surgery, such as temperature, airflow, and hydration. Surface roughness plays an important role in accurate measurement of ablation performance on calibration materials. The ratio of ablation efficiency between the human cornea and calibration material is very critical and highly dependent on the laser beam characteristics and test conditions. Objective evaluation of the calibration data and corresponding adjustment of the laser systems at regular intervals are essential for the continuing success and further improvements in outcomes of laser vision correction procedures.

  11. Automatic camera to laser calibration for high accuracy mobile mapping systems using INS

    Science.gov (United States)

    Goeman, Werner; Douterloigne, Koen; Gautama, Sidharta

    2013-09-01

    A mobile mapping system (MMS) is a mobile multi-sensor platform developed by the geoinformation community to support the acquisition of huge amounts of geodata in the form of georeferenced high resolution images and dense laser clouds. Since data fusion and data integration techniques are increasingly able to combine the complementary strengths of different sensor types, the external calibration of a camera to a laser scanner is a common pre-requisite on today's mobile platforms. The methods of calibration, nevertheless, are often relatively poorly documented, are almost always time-consuming, demand expert knowledge and often require a carefully constructed calibration environment. A new methodology is studied and explored to provide a high quality external calibration for a pinhole camera to a laser scanner which is automatic, easy to perform, robust and foolproof. The method presented here, uses a portable, standard ranging pole which needs to be positioned on a known ground control point. For calibration, a well studied absolute orientation problem needs to be solved. In many cases, the camera and laser sensor are calibrated in relation to the INS system. Therefore, the transformation from camera to laser contains the cumulated error of each sensor in relation to the INS. Here, the calibration of the camera is performed in relation to the laser frame using the time synchronization between the sensors for data association. In this study, the use of the inertial relative movement will be explored to collect more useful calibration data. This results in a better intersensor calibration allowing better coloring of the clouds and a more accurate depth mask for images, especially on the edges of objects in the scene.

  12. Effective Data-Driven Calibration for a Galvanometric Laser Scanning System Using Binocular Stereo Vision.

    Science.gov (United States)

    Tu, Junchao; Zhang, Liyan

    2018-01-12

    A new solution to the problem of galvanometric laser scanning (GLS) system calibration is presented. Under the machine learning framework, we build a single-hidden layer feedforward neural network (SLFN)to represent the GLS system, which takes the digital control signal at the drives of the GLS system as input and the space vector of the corresponding outgoing laser beam as output. The training data set is obtained with the aid of a moving mechanism and a binocular stereo system. The parameters of the SLFN are efficiently solved in a closed form by using extreme learning machine (ELM). By quantitatively analyzing the regression precision with respective to the number of hidden neurons in the SLFN, we demonstrate that the proper number of hidden neurons can be safely chosen from a broad interval to guarantee good generalization performance. Compared to the traditional model-driven calibration, the proposed calibration method does not need a complex modeling process and is more accurate and stable. As the output of the network is the space vectors of the outgoing laser beams, it costs much less training time and can provide a uniform solution to both laser projection and 3D-reconstruction, in contrast with the existing data-driven calibration method which only works for the laser triangulation problem. Calibration experiment, projection experiment and 3D reconstruction experiment are respectively conducted to test the proposed method, and good results are obtained.

  13. Effective Data-Driven Calibration for a Galvanometric Laser Scanning System Using Binocular Stereo Vision

    Directory of Open Access Journals (Sweden)

    Junchao Tu

    2018-01-01

    Full Text Available A new solution to the problem of galvanometric laser scanning (GLS system calibration is presented. Under the machine learning framework, we build a single-hidden layer feedforward neural network (SLFN)to represent the GLS system, which takes the digital control signal at the drives of the GLS system as input and the space vector of the corresponding outgoing laser beam as output. The training data set is obtained with the aid of a moving mechanism and a binocular stereo system. The parameters of the SLFN are efficiently solved in a closed form by using extreme learning machine (ELM. By quantitatively analyzing the regression precision with respective to the number of hidden neurons in the SLFN, we demonstrate that the proper number of hidden neurons can be safely chosen from a broad interval to guarantee good generalization performance. Compared to the traditional model-driven calibration, the proposed calibration method does not need a complex modeling process and is more accurate and stable. As the output of the network is the space vectors of the outgoing laser beams, it costs much less training time and can provide a uniform solution to both laser projection and 3D-reconstruction, in contrast with the existing data-driven calibration method which only works for the laser triangulation problem. Calibration experiment, projection experiment and 3D reconstruction experiment are respectively conducted to test the proposed method, and good results are obtained.

  14. A NEW ELECTRONIC BOARD TO DRIVE THE LASER CALIBRATION SYSTEM OF THE ATLAS HADRON CALORIMETER

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00086824; The ATLAS collaboration

    2016-01-01

    The LASER calibration system of the ATLAS hadron calorimeter aims at monitoring the ~10000 PMTs of the TileCal. The LASER light injected in the PMTs is measured by sets of photodiodes at several stages of the optical path. The monitoring of the photodiodes is performed by a redundant internal calibration system using an LED, a radioactive source, and a charge injection system. The LASer Calibration Rod (LASCAR) electronics card is a major component of the LASER calibration scheme. Housed in a VME crate, its main components include a charge ADC, a TTCRx, a HOLA part, an interface to control the LASER, and a charge injection system. The 13 bits ADC is a 2000pc full-scale converter that processes up to 16 signals stemming from 11 photodiodes, 2 PMTs, and 3 charge injection channels. Two gains are used (x1 and x4) to increase the dynamic range and avoid a saturation of the LASER signal for high intensities. The TTCRx chip (designed by CERN) retrieves LHC signals to synchronize the LASCAR card with the collider. T...

  15. Investigation into the accuracy of a proposed laser diode based multilateration machine tool calibration system

    International Nuclear Information System (INIS)

    Fletcher, S; Longstaff, A P; Myers, A

    2005-01-01

    Geometric and thermal calibration of CNC machine tools is required in modern machine shops with volumetric accuracy assessment becoming the standard machine tool qualification in many industries. Laser interferometry is a popular method of measuring the errors but this, and other alternatives, tend to be expensive, time consuming or both. This paper investigates the feasibility of using a laser diode based system that capitalises on the low cost nature of the diode to provide multiple laser sources for fast error measurement using multilateration. Laser diode module technology enables improved wavelength stability and spectral linewidth which are important factors for laser interferometry. With more than three laser sources, the set-up process can be greatly simplified while providing flexibility in the location of the laser sources improving the accuracy of the system

  16. Self-calibration method for rotating laser positioning system using interscanning technology and ultrasonic ranging.

    Science.gov (United States)

    Wu, Jun; Yu, Zhijing; Zhuge, Jingchang

    2016-04-01

    A rotating laser positioning system (RLPS) is an efficient measurement method for large-scale metrology. Due to multiple transmitter stations, which consist of a measurement network, the position relationship of these stations must be first calibrated. However, with such auxiliary devices such as a laser tracker, scale bar, and complex calibration process, the traditional calibration methods greatly reduce the measurement efficiency. This paper proposes a self-calibration method for RLPS, which can automatically obtain the position relationship. The method is implemented through interscanning technology by using a calibration bar mounted on the transmitter station. Each bar is composed of three RLPS receivers and one ultrasonic sensor whose coordinates are known in advance. The calibration algorithm is mainly based on multiplane and distance constraints and is introduced in detail through a two-station mathematical model. The repeated experiments demonstrate that the coordinate measurement uncertainty of spatial points by using this method is about 0.1 mm, and the accuracy experiments show that the average coordinate measurement deviation is about 0.3 mm compared with a laser tracker. The accuracy can meet the requirements of most applications, while the calibration efficiency is significantly improved.

  17. The laser system for calibration and monotoring of the Opal jet chamber

    International Nuclear Information System (INIS)

    Biebel, O.; Boden, B.; Bug, S.; Eyring, A.; Fischer, H.M.; Geich-Gimbel, C.; Gross, S.; Knop, G.; Levegruen, S.; Maringer, G.; Mauer, E.; Maur, U.; Nellen, B.; Neumann, H.; Rollnik, A.; Schreiber, S.; Simon, A.; Thiebes, J.; Wolf, B.; Wuensch, B.; Boerner, H.; Breuker, H.; Hagemann, J.; Hauschild, M.; Heuer, R.D.; Karner, K.; Linser, G.; Runolfsson, O.; Seidl, W.; Voillat, D.; Wicht, P.; Schmitt, H. von der; Wagner, A.

    1992-01-01

    In this report we describe the construction and performance of the laser system which was used in Summer 1989 for the initial calibration of the OPAL jet chamber after installation on the LEP beam axis and which has served as a monitoring tool since then. Two Nd:YAG lasers are used to generate 48 high precision double beams which enter the chamber at fixed positions. The main features of the roughly 450 optical components are described and the beam alignment procedures are explained. Results are given for jet chamber calibration constants such as drift velocity, Lorentz angle, and residual sagittas. (orig.)

  18. A novel calibration method for non-orthogonal shaft laser theodolite measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Bin, E-mail: wubin@tju.edu.cn, E-mail: xueting@tju.edu.cn; Yang, Fengting; Ding, Wen [State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072 (China); Xue, Ting, E-mail: wubin@tju.edu.cn, E-mail: xueting@tju.edu.cn [College of Electrical Engineering and Automation, Tianjin Key Laboratory of Process Measurement and Control, Tianjin University, Tianjin 300072 (China)

    2016-03-15

    Non-orthogonal shaft laser theodolite (N-theodolite) is a new kind of large-scale metrological instrument made up by two rotary tables and one collimated laser. There are three axes for an N-theodolite. According to naming conventions in traditional theodolite, rotary axes of two rotary tables are called as horizontal axis and vertical axis, respectively, and the collimated laser beam is named as sight axis. And the difference between N-theodolite and traditional theodolite is obvious, since the former one with no orthogonal and intersecting accuracy requirements. So the calibration method for traditional theodolite is no longer suitable for N-theodolite, while the calibration method applied currently is really complicated. Thus this paper introduces a novel calibration method for non-orthogonal shaft laser theodolite measurement system to simplify the procedure and to improve the calibration accuracy. A simple two-step process, calibration for intrinsic parameters and for extrinsic parameters, is proposed by the novel method. And experiments have shown its efficiency and accuracy.

  19. Development of the laser alignment system with PSD used for shaft calibration

    Science.gov (United States)

    Jiao, Guohua; Li, Yulin; Hu, Baowen

    2006-02-01

    Shaft calibration is an important technique during installation and maintenance of a rotating machine. It requires unique and high-precision measurement instruments with calculation capability, and relies on experience on heavy, high-speed, or high-temperature machines. A high-precision laser alignment system has been designed using PSD (Position Sensing Detector) to change traditional manual way of shaft calibration and to make the measurement easier and more accurate. The system is comprised of two small measuring units (Laser transmitter and detector) and a hand operated control unit or a PC. Such a laser alignment system has been used in some actual shaft alignment with offset resolution 1.5μm and angular resolution 0.1°.

  20. Laser guided automated calibrating system for accurate bracket ...

    African Journals Online (AJOL)

    It is widely recognized that accurate bracket placement is of critical importance in the efficient application of biomechanics and in realizing the full potential of a preadjusted edgewise appliance. Aim: The purpose of ... placement. Keywords: Hough transforms, Indirect bonding technique, Laser, Orthodontic bracket placement ...

  1. The laser calibration system for the STACEE ground-based gamma ray detector

    CERN Document Server

    Hanna, D

    2002-01-01

    We describe the design and performance of the laser system used for calibration monitoring of components of the STACEE detector. STACEE is a ground based gamma ray detector which uses the heliostats of a solar power facility to collect and focus Cherenkov light onto a system of secondary optics and photomultiplier tubes. To monitor the gain and check the linearity and timing properties of the phototubes and associated electronics, a system based on a dye laser, neutral density filters and optical fibres has been developed. In this paper we describe the system and present some results from initial tests made with it.

  2. PMT response drift of ATLAS Tile Laser II calibration system: an introduction of a new method

    CERN Document Server

    Di Gregorio, Giulia

    2016-01-01

    In this article I describe the performance of the monitoring diodes of the Laser II system, a new system for run II used to calibrate the gain variation of PMTs in between two cesium scan. I also show a new method to measure the PMT drift response that it is compared to the method used up to now (Clermont-Ferrant) corrected with the Pisa method. The agreement between the two method is within 0.2%.

  3. EAST-AIA deployment under vacuum: Calibration of laser diagnostic system using computer vision

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yang, E-mail: yangyang@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd, Hefei, Anhui (China); Song, Yuntao; Cheng, Yong; Feng, Hansheng; Wu, Zhenwei; Li, Yingying; Sun, Yongjun; Zheng, Lei [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd, Hefei, Anhui (China); Bruno, Vincent; Eric, Villedieu [CEA-IRFM, F-13108 Saint-Paul-Lez-Durance (France)

    2016-11-15

    Highlights: • The first deployment of the EAST articulated inspection arm robot under vacuum is presented. • A computer vision based approach to measure the laser spot displacement is proposed. • An experiment on the real EAST tokamak is performed to validate the proposed measure approach, and the results shows that the measurement accuracy satisfies the requirement. - Abstract: For the operation of EAST tokamak, it is crucial to ensure that all the diagnostic systems are in the good condition in order to reflect the plasma status properly. However, most of the diagnostic systems are mounted inside the tokamak vacuum vessel, which makes them extremely difficult to maintain under high vacuum condition during the tokamak operation. Thanks to a system called EAST articulated inspection arm robot (EAST-AIA), the examination of these in-vessel diagnostic systems can be performed by an embedded camera carried by the robot. In this paper, a computer vision algorithm has been developed to calibrate a laser diagnostic system with the help of a monocular camera at the robot end. In order to estimate the displacement of the laser diagnostic system with respect to the vacuum vessel, several visual markers were attached to the inner wall. This experiment was conducted both on the EAST vacuum vessel mock-up and the real EAST tokamak under vacuum condition. As a result, the accuracy of the displacement measurement was within 3 mm under the current camera resolution, which satisfied the laser diagnostic system calibration.

  4. Calibration of a multi-beam Laser System by using a TLS-generated Reference

    Directory of Open Access Journals (Sweden)

    M. Gordon

    2013-10-01

    Full Text Available Rotating multi-beam LIDARs mounted on moving platforms have become very successful for many applications such as autonomous navigation, obstacle avoidance or mobile mapping. To obtain accurate point coordinates, a precise calibration of such a LIDAR system is required. For the determination of the corresponding parameters we propose a calibration scheme which exploits the information of 3D reference point clouds captured by a terrestrial laser scanning (TLS device. It is assumed that the accuracy of this point clouds is considerably higher than that from the multi-beam LIDAR and that the data represent faces of man-made objects at different distances. After extracting planes in the reference data sets, the point-plane-incidences of the measured points and the reference planes are used to formulate the implicit constraints. We inspect the Velodyne HDL-64E S2 system as the best-known representative for this kind of sensor system. The usability and feasibility of the calibration procedure is demonstrated with real data sets representing building faces (walls, roof planes and ground. Beside the improvement of the point accuracy by considering the calibration results, we test the significance of the parameters related to the sensor model and consider the uncertainty of measurements w.r.t. the measured distances. The Velodyne returns two kinds of measurements – distances and encoder angles. To account for this, we perform a variance component estimation to obtain realistic standard deviations for the observations.

  5. Electron beam test of key elements of the laser-based calibration system for the muon g - 2 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Anastasi, A., E-mail: antonioanastasi89@gmail.com [Laboratori Nazionali Frascati dell' INFN, Via E. Fermi 40, 00044 Frascati (Italy); Dipartimento MIFT, Università di Messina, Messina (Italy); Basti, A.; Bedeschi, F.; Bartolini, M. [INFN, Sezione di Pisa (Italy); Cantatore, G. [INFN, Sezione di Trieste e G.C. di Udine (Italy); Università di Trieste, Trieste (Italy); Cauz, D. [INFN, Sezione di Trieste e G.C. di Udine (Italy); Università di Udine, Udine (Italy); Corradi, G. [Laboratori Nazionali Frascati dell' INFN, Via E. Fermi 40, 00044 Frascati (Italy); Dabagov, S. [Laboratori Nazionali Frascati dell' INFN, Via E. Fermi 40, 00044 Frascati (Italy); Lebedev Physical Institute and NRNU MEPhI, Moscow (Russian Federation); Di Sciascio, G. [INFN, Sezione di Roma Tor Vergata, Roma (Italy); Di Stefano, R. [INFN, Sezione di Napoli (Italy); Università di Cassino, Cassino (Italy); Driutti, A. [INFN, Sezione di Trieste e G.C. di Udine (Italy); Università di Udine, Udine (Italy); Escalante, O. [Università di Napoli, Napoli (Italy); Ferrari, C. [Laboratori Nazionali Frascati dell' INFN, Via E. Fermi 40, 00044 Frascati (Italy); Istituto Nazionale di Ottica del C.N.R., UOS Pisa, via Moruzzi 1, 56124, Pisa (Italy); Fienberg, A.T. [University of Washington, Box 351560, Seattle, WA 98195 (United States); Fioretti, A.; Gabbanini, C. [Laboratori Nazionali Frascati dell' INFN, Via E. Fermi 40, 00044 Frascati (Italy); Istituto Nazionale di Ottica del C.N.R., UOS Pisa, via Moruzzi 1, 56124, Pisa (Italy); Gioiosa, A. [INFN, Sezione di Lecce (Italy); Università del Molise, Pesche (Italy); Hampai, D. [Laboratori Nazionali Frascati dell' INFN, Via E. Fermi 40, 00044 Frascati (Italy); Hertzog, D.W. [University of Washington, Box 351560, Seattle, WA 98195 (United States); and others

    2017-01-11

    We report the test of many of the key elements of the laser-based calibration system for muon g - 2 experiment E989 at Fermilab. The test was performed at the Laboratori Nazionali di Frascati's Beam Test Facility using a 450 MeV electron beam impinging on a small subset of the final g - 2 lead-fluoride crystal calorimeter system. The calibration system was configured as planned for the E989 experiment and uses the same type of laser and most of the final optical elements. We show results regarding the calorimeter's response calibration, the maximum equivalent electron energy which can be provided by the laser and the stability of the calibration system components.

  6. Electron beam test of key elements of the laser-based calibration system for the muon g - 2 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Anastasi, A.; Basti, A.; Bedeschi, F.; Bartolini, M.; Cantatore, G.; Cauz, D.; Corradi, G.; Dabagov, S.; Di Sciascio, G.; Di Stefano, R.; Driutti, A.; Escalante, O.; Ferrari, C.; Fienberg, A. T.; Fioretti, A.; Gabbanini, C.; Gioiosa, A.; Hampai, D.; Hertzog, D. W.; Iacovacci, M.; Karuza, M.; Kaspar, J.; Liedl, A.; Lusiani, A.; Marignetti, F.; Mastroianni, S.; Moricciani, D.; Pauletta, G.; Piacentino, G. M.; Raha, N.; Rossi, E.; Santi, L.; Venanzoni, G.

    2017-01-01

    We report the test of many of the key elements of the laser-based calibration system for muon g - 2 experiment E989 at Fermilab. The test was performed at the Laboratori Nazionali di Frascati's Beam Test Facility using a 450 MeV electron beam impinging on a small subset of the final g - 2 lead-fluoride crystal calorimeter system. The calibration system was configured as planned for the E989 experiment and uses the same type of laser and most of the final optical elements. We show results regarding the calorimeter's response calibration, the maximum equivalent electron energy which can be provided by the laser and the stability of the calibration system components.

  7. Studies on the beam system for the calibration of the OPAL jet chamber with laser beams

    International Nuclear Information System (INIS)

    Maringer, G.

    1988-07-01

    UV laser beams are an important tool for the calibration of the OPAL jet chamber. A beam transport system containing about 350 mirrors in total guides the beams from the laser outside the detector into the chamber. Four of the mirrors are moveable under remote control allowing to guide the beams into each of the 24 sectors and to correct the beam path in case of deviations. A program to control these moveable mirrors has been developed. Drift velocity measurements will be performed by means of double beams which are generated by appropriate beamsplitters. Accurate knowledge of the double beam distances is essential to obtain the desired accuracy of better than 0.1% or 10 μm. Using a CCD device with a pixel size of 23x23 μm 2 the beam distance could be measured with errors below the required limit. (orig.)

  8. The upgrade of the laser calibration system for the ATLAS hadron calorimeter TileCal

    CERN Document Server

    Spalla, Margherita; The ATLAS collaboration

    2014-01-01

    The Tile Calorimeter (TileCal), the central section of the hadronic calorimeter of the ATLAS experiment, is a key detector component to detect hadrons, jets and taus and to measure the missing transverse energy. TileCal is built of steel and scintillating tiles coupled to optical fibers and read‐out by photomultipliers (PMT). The performance of TileCal relies on a continuous, high resolution calibration of the individual response of the 10,000 channels forming the detector. The calibration is based on a three level architecture: a charge injection system used to monitor the full electronics chain including front-end amplifiers, digitizers and event builder blocks for each individual channel; a distributed optical system using laser pulses to excite all PMTs; and a mobile Cesium radiative source which is driven through the detector cell floating inside a pipe system. This architecture allows for a cascade calibration of the electronics, of the PMT and electronics, and of full chain including the active detec...

  9. Time Calibration of the ATLAS Hadronic Tile Calorimeter using the Laser System

    CERN Document Server

    Clément, C; Solovyanov, O; Vivarelli, I

    2008-01-01

    The ATLAS Tile Calorimeter (TileCal) will be used to measure i) the energy of hadronic showers and ii) the Time of Flight (ToF) of particles passing through it. To allow for optimal reconstruction of the energy deposited in the calorimeter with optimal filtering, the phase between the signal sampling clock and the maximum of the incoming pulses needs to be minimised and the residual difference needs to be measured for later use for both energy and time of flight measurements. In this note we present the timing equalisation of all TileCal read out channels using the TileCal laser calibration system and a measurement of the time differences between the 4 TileCal TTC partitions. The residual phases after timing equalisation have been measured. Several characteristics of the laser calibration system relevant for timing have also been studied and a solution is proposed to take into account the time difference between the high and low gain paths. Finally we discuss the sources of uncertainties on the timing of the ...

  10. Construction and calibration of the laser alignment system for the CMS tracker

    International Nuclear Information System (INIS)

    Adolphi, R.

    2006-01-01

    A robust and reliable optical system able to measure and control the large CMS tracker geometry with high accuracy has been developed and validated. The construction and integration of the LAS fulfilling the requirements, as well as its calibration and performance are described in this thesis. The working principle is based on the partial transparency of silicon for light wavelengths in the near infrared region. The absorbed part of the laser beam generates a signal in the corresponding silicon strip module serving to reconstruct its position. The transmitted part reaches the subsequent module layer generating an optical link between the two layers. Investigation of the light generation and distribution led to a definition of the optical components and their optimization for Laser Alignment purposes. Laser diodes have been qualified as light sources and singlemode optical fibres, terminated by special connectors, distribute the light to the CMS tracker detector. The beamsplitting device, a key component of the LAS light distribution inside the CMS tracker, has been studied in detail. The challenge of splitting one collimated beam into two back-to-back beams inside a small available volume has been solved by using the polarization principle. Special test setups were developed to determine the collinearity of the two outgoing beams with a precision better than 50 μrad and it has been shown that their relative orientation remains constant under working conditions. The interface between the tracker and the LAS is given by the silicon sensors which are responsible both for particle detection and for the determination of the position of the laser spot. An anti-reflex-coating has been applied on the backside of all alignment sensors to improve their optical properties without deterioration of their tracking performance. A test setup has been developed to simultaneously study the transmission and reflection properties of the alignment sensors. The working principle of the

  11. Construction and calibration of the laser alignment system for the CMS tracker

    Energy Technology Data Exchange (ETDEWEB)

    Adolphi, R.

    2006-11-28

    A robust and reliable optical system able to measure and control the large CMS tracker geometry with high accuracy has been developed and validated. The construction and integration of the LAS fulfilling the requirements, as well as its calibration and performance are described in this thesis. The working principle is based on the partial transparency of silicon for light wavelengths in the near infrared region. The absorbed part of the laser beam generates a signal in the corresponding silicon strip module serving to reconstruct its position. The transmitted part reaches the subsequent module layer generating an optical link between the two layers. Investigation of the light generation and distribution led to a definition of the optical components and their optimization for Laser Alignment purposes. Laser diodes have been qualified as light sources and singlemode optical fibres, terminated by special connectors, distribute the light to the CMS tracker detector. The beamsplitting device, a key component of the LAS light distribution inside the CMS tracker, has been studied in detail. The challenge of splitting one collimated beam into two back-to-back beams inside a small available volume has been solved by using the polarization principle. Special test setups were developed to determine the collinearity of the two outgoing beams with a precision better than 50 {mu}rad and it has been shown that their relative orientation remains constant under working conditions. The interface between the tracker and the LAS is given by the silicon sensors which are responsible both for particle detection and for the determination of the position of the laser spot. An anti-reflex-coating has been applied on the backside of all alignment sensors to improve their optical properties without deterioration of their tracking performance. A test setup has been developed to simultaneously study the transmission and reflection properties of the alignment sensors. The working principle of

  12. The design and development of CO2 medium-level laser power calibration system for industrial and medical applications in Thailand

    Science.gov (United States)

    Nontapot, Kanokwan

    2018-03-01

    The carbon dioxide laser (CO2 laser) is one of the most useful and is the highest CW laser at the present. The laser produces infrared light at 10.6 um. Due to its high power, CO2 lasers are usually used in industrial applications such as cutting and welding, or for engraving at less power. CO2 lasers are also used widely in medical applications, such as laser surgery, skin resurfacing, and removing mold, due to water (biological tissue) absorb light at this wavelength very well. CO2 lasers are also used as LIDAR laser source for military range finding applications because of the transparency of the atmosphere to infrared light. Due to the increasing use of CO2 lasers laser in industrial and medical applications in Thailand, the National Institute of Metrology (Thailand) has set up a CO2 laser power calibration system and provide calibration service to customers this year. The service support calibration of medium-level laser power at wavelength of 10.6 um and at power range 100 mW-10W. The design and development of the calibration system will be presented.

  13. The Light Plane Calibration Method of the Laser Welding Vision Monitoring System

    Science.gov (United States)

    Wang, B. G.; Wu, M. H.; Jia, W. P.

    2018-03-01

    According to the aerospace and automobile industry, the sheet steels are the very important parts. In the recent years, laser welding technique had been used to weld the sheet steel part. The seam width between the two parts is usually less than 0.1mm. Because the error of the fixture fixed can’t be eliminated, the welding parts quality can be greatly affected. In order to improve the welding quality, the line structured light is employed in the vision monitoring system to plan the welding path before welding. In order to improve the weld precision, the vision system is located on Z axis of the computer numerical control (CNC) tool. The planar pattern is placed on the X-Y plane of the CNC tool, and the structured light is projected on the planar pattern. The vision system stay at three different positions along the Z axis of the CNC tool, and the camera shoot the image of the planar pattern at every position. Using the calculated the sub-pixel center line of the structure light, the world coordinate of the center light line can be calculated. Thus, the structured light plane can be calculated by fitting the structured light line. Experiment result shows the effective of the proposed method.

  14. Construction and Calibration of the Laser Alignment System for the CMS Tracker

    CERN Document Server

    Adolphi, Roman

    2006-01-01

    The CMS detector (Compact Muon Solenoid) is under construction at one of the four proton-proton interaction points of the LHC (Large Hadron Collider) at CERN, the European Organization for Nuclear Research (Geneva, Switzerland). The inner tracking system of the CMS experiment consisting of silicon detectors will have a diameter of 2.4 m and a length of 5.4 m representing the largest silicon tracker ever. About 15000 silicon strip modules create an active silicon area of 200 m2 to detect charged particles from proton collisions. They are placed on a rigid carbon fibre structure, providing stability within the working conditions of a 4 T solenoid magnetic field at −10oC. Knowledge of the position of the silicon detectors at the level of 100 μm is needed for an efficient pattern recognition of charged particle tracks. Metrology methods are used to survey tracker subdetectors and the integrated Laser Alignment System (LAS) provides absolute positioning of support structure elements to better than 100 μm. Rela...

  15. The GERDA calibration system

    Energy Technology Data Exchange (ETDEWEB)

    Baudis, Laura; Froborg, Francis; Tarka, Michael; Bruch, Tobias; Ferella, Alfredo [Physik-Institut, Universitaet Zuerich (Switzerland); Collaboration: GERDA-Collaboration

    2012-07-01

    A system with three identical custom made units is used for the energy calibration of the GERDA Ge diodes. To perform a calibration the {sup 228}Th sources are lowered from the parking positions at the top of the cryostat. Their positions are measured by two independent modules. One, the incremental encoder, counts the holes in the perforated steel band holding the sources, the other measures the drive shaft's angular position even if not powered. The system can be controlled remotely by a Labview program. The calibration data is analyzed by an iterative calibration algorithm determining the calibration functions for different energy reconstruction algorithms and the resolution of several peaks in the {sup 228}Th spectrum is determined. A Monte Carlo simulation using the GERDA simulation software MAGE has been performed to determine the background induced by the sources in the parking positions.

  16. BES online calibration system

    International Nuclear Information System (INIS)

    Zhang Bingyun; Li Xiaonan; Zhu Kejun; Zhang Jiawen; Gong Mingyu

    2003-01-01

    We constructed BES (Beijing Spectrometer) online calibration system to ensure the coherence of readout electronic channels due to huge data volume in high energy physics experiment. This paper describes the structure of hardware and software, and its characteristic and function

  17. High-density volatiles in the system C-O-H-N for the calibration of a laser Raman microprobe

    Science.gov (United States)

    Chou, I.-Ming; Pasteris, J.D.; Seitz, J.C.

    1990-01-01

    Three methods have been used to produce high-density volatiles in the system C-O-H-N for the calibration of a laser Raman microprobe (LRM): synthetic fluid-inclusion, sealed fused-quartz-tube, and high-pressure-cell methods. Because quantitative interpretation of a Raman spectrum of mixed-volatile fluid inclusions requires accurate knowledge of pressure- and composition-sensitive Raman scattering efficiencies or quantification factors for each species, calibrations of these parameters for mixtures of volatiles of known composition and pressure are necessary. Two advantages of the synthetic fluid-inclusion method are that the inclusions can be used readily in complementary microthermometry (MT) studies and that they have sizes and optical properties like those in natural samples. Some disadvantages are that producing H2O-free volatile mixtures is difficult, the composition may vary from one inclusion to another, the exact composition and density of the inclusions are difficult to obtain, and the experimental procedures are complicated. The primary advantage of the method using sealed fused-quartz tubes is its simplicity. Some disadvantages are that exact compositions for complex volatile mixtures are difficult to predict, densities can be approximated only, and complementary MT studies on the tubes are difficult to conduct. The advantages of the high-pressure-cell method are that specific, known compositions of volatile mixtures can be produced and that their pressures can be varied easily and are monitored during calibration. Some disadvantages are that complementary MT analysis is impossible, and the setup is bulky. Among the three methods for the calibration of an LRM, the high-pressure-cell method is the most reliable and convenient for control of composition and total pressure. We have used the high-pressure cell to obtain preliminary data on 1. (1) the ratio of the Raman quantification factors for CH4 and N2 in an equimolar CH4N2 mixture and 2. (2) the

  18. RADIOMETRIC CALIBRATION OF AIRBORNE LASER SCANNING DATA

    OpenAIRE

    Pilarska Magdalena

    2016-01-01

    Airborne laser scanning (ALS) is widely used passive remote sensing technique. The radiometric calibration of ALS data is presented in this article. This process is a necessary element in data processing since it eliminates the influence of the external factors on the obtained values of radiometric features such as range and incidence angle. The datasets were captured with three different laser scanners; since each of these operates at a different wavelength (532, 106 4 and 1550 nm) th...

  19. Gamma ray calibration system

    International Nuclear Information System (INIS)

    Rosauer, P.J.; Flaherty, J.J.

    1981-01-01

    This invention is in the field of gamma ray inspection devices for tubular products and the like employing an improved calibrating block which prevents the sensing system from being overloaded when no tubular product is present, and also provides the operator with a means for visually detecting the presence of wall thicknesses which are less than a required minimum. (author)

  20. Laser Calibration of the ATLAS Tile Calorimeter

    CERN Document Server

    Di Gregorio, Giulia; The ATLAS collaboration

    2017-01-01

    High performance stability of the ATLAS Tile Calorimeter is achieved with a set of calibration procedures. One step of the calibration procedure is based on measurements of the response stability to laser excitation of the PMTs that are used to readout the calorimeter cells. A facility to study in lab the PMT stability response is operating in the PISA-INFN laboratories since 2015. Goals of the tests in lab are to study the time evolution of the PMT response to reproduce and to understand the origin of the response drifts seen with the PMT mounted on the Tile calorimeter in its normal operating during LHC run I and run II. A new statistical approach was developed to measure drift of the absolute gain. This approach was applied to both the ATLAS laser calibration data and to data collected in the Pisa local laboratory. The preliminary results from these two studies are shown.

  1. Construction and calibration of the laser alignment system for the CMS tracker

    OpenAIRE

    Adolphi, Roman

    2006-01-01

    The CMS detector (Compact Muon Solenoid) is under construction at one of the four proton-proton interaction points of the LHC (Large Hadron Collider) at CERN, the European Organization for Nuclear Research (Geneva, Switzerland). The inner tracking system of the CMS experiment consisting of silicon detectors will have a diameter of 2.4 meter and a length of 5.4 meter representing the largest silicon tracker ever. About 15000 silicon strip modules create an active silicon area of 200 square met...

  2. A compact and low cost laser induced breakdown spectroscopic system: Application for simultaneous determination of chromium and nickel in steel using multivariate calibration

    Energy Technology Data Exchange (ETDEWEB)

    Barbieri Gonzaga, Fabiano [Chemical Metrology Division, National Institute of Metrology, Quality and Technology, Av. N. S. das Gracas, 50, Xerem, 25250-020, Duque de Caxias, RJ (Brazil); Pasquini, Celio, E-mail: pasquini@iqm.unicamp.br [Institute of Chemistry, State University of Campinas, POB 6154, 13083-970, Campinas, SP (Brazil)

    2012-03-15

    This work describes a compact and low cost analyzer for laser induced breakdown spectroscopy (LIBS) based on a diode pumped passively Q-switched Nd:LSB microchip laser and a conventional Czerny-Turner spectrograph (spectral range from about 250 to 390 nm) containing a non-intensified, non-gated and non-cooled 1024 pixel linear sensor array. The new LIBS instrument was applied for analyzing steel samples containing chromium and nickel in the concentration range from about 5 to 26% w/w (certified reference materials), integrating the emitted radiation for 40 s under continuous application of laser pulses at 2 kHz for each acquired spectrum (integration of about 80,000 plasmas). The emission data from about 356 to 362 nm and 340 to 354 nm were employed for the construction of two Partial Least Squares (PLS) calibration models for determination of chromium and nickel, respectively. The average relative errors of prediction of chromium and nickel concentrations were 3.7 and 6.7%, respectively, which are similar to or lower than those obtained using higher cost LIBS analyzers. The results have shown that multivariate calibration can help to overcome the decreasing instrumental performance associated with the low cost equipment. - Highlights: Black-Right-Pointing-Pointer Low cost laser induced breakdown spectroscopy instrumentation. Black-Right-Pointing-Pointer Microchip laser based LIBS system. Black-Right-Pointing-Pointer Standard non-intensified, non-gated, non-cooled detector for LIBS system. Black-Right-Pointing-Pointer Improvement of results from a low cost LIBS system using multivariate calibration. Black-Right-Pointing-Pointer Cr and Ni determination in steel by a low cost LIBS system.

  3. A laser sheet self-calibration method for scanning PIV

    Science.gov (United States)

    Knutsen, Anna N.; Lawson, John M.; Dawson, James R.; Worth, Nicholas A.

    2017-10-01

    Knowledge of laser sheet position, orientation, and thickness is a fundamental requirement of scanning PIV and other laser-scanning methods. This paper describes the development and evaluation of a new laser sheet self-calibration method for stereoscopic scanning PIV, which allows the measurement of these properties from particle images themselves. The approach is to fit a laser sheet model by treating particles as randomly distributed probes of the laser sheet profile, whose position is obtained via a triangulation procedure enhanced by matching particle images according to their variation in brightness over a scan. Numerical simulations and tests with experimental data were used to quantify the sensitivity of the method to typical experimental error sources and validate its performance in practice. The numerical simulations demonstrate the accurate recovery of the laser sheet parameters over range of different seeding densities and sheet thicknesses. Furthermore, they show that the method is robust to significant image noise and camera misalignment. Tests with experimental data confirm that the laser sheet model can be accurately reconstructed with no impairment to PIV measurement accuracy. The new method is more efficient and robust in comparison with the standard (self-) calibration approach, which requires an involved, separate calibration step that is sensitive to experimental misalignments. The method significantly improves the practicality of making accurate scanning PIV measurements and broadens its potential applicability to scanning systems with significant vibrations.

  4. Laser calibration of the ATLAS Tile Calorimeter

    CERN Document Server

    Di Gregorio, Giulia; The ATLAS collaboration

    2017-01-01

    High performance stability of the ATLAS Tile calorimeter is achieved with a set of calibration procedures. One step of the calibrtion procedure is based on measurements of the response stability to laser excitation of the photomultipliers (PMTs) that are used to readout the calorimeter cells. A facility to study in lab the PMT stability response is operating in the PISA-INFN laboratories since 2015. Goals of the test in lab are to study the time evolution of the PMT response to reproduce and to understand the origin of the resonse drifts seen with the PMT mounted on the Tile calorimeter in its normal operation during LHC run I and run II. A new statistical approach was developed to measure the drift of the absolute gain. This approach was applied to both the ATLAS laser calibration data and to the data collected in the Pisa local laboratory. The preliminary results from these two studies are shown.

  5. Simple laser vision sensor calibration for surface profiling applications

    Science.gov (United States)

    Abu-Nabah, Bassam A.; ElSoussi, Adnane O.; Al Alami, Abed ElRahman K.

    2016-09-01

    Due to the relatively large structures in the Oil and Gas industry, original equipment manufacturers (OEMs) have been implementing custom-designed laser vision sensor (LVS) surface profiling systems as part of quality control in their manufacturing processes. The rough manufacturing environment and the continuous movement and misalignment of these custom-designed tools adversely affect the accuracy of laser-based vision surface profiling applications. Accordingly, Oil and Gas businesses have been raising the demand from the OEMs to implement practical and robust LVS calibration techniques prior to running any visual inspections. This effort introduces an LVS calibration technique representing a simplified version of two known calibration techniques, which are commonly implemented to obtain a calibrated LVS system for surface profiling applications. Both calibration techniques are implemented virtually and experimentally to scan simulated and three-dimensional (3D) printed features of known profiles, respectively. Scanned data is transformed from the camera frame to points in the world coordinate system and compared with the input profiles to validate the introduced calibration technique capability against the more complex approach and preliminarily assess the measurement technique for weld profiling applications. Moreover, the sensitivity to stand-off distances is analyzed to illustrate the practicality of the presented technique.

  6. ATLAS Tile calorimeter calibration and monitoring systems

    CERN Document Server

    Marjanovic, Marija; The ATLAS collaboration

    2018-01-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibers to photo-multiplier tubes (PMTs), located in the outer part of the calorimeter. The readout is segmented into about 5000 cells, each one being read out by two PMTs in parallel. To calibrate and monitor the stability and performance of the full readout chain during the data taking, a set of calibration sub-systems is used. The TileCal calibration system comprises Cesium radioactive sources, laser, charge injection elements, and an integrator based readout system. Combined information from all systems allows to monitor and to equalize the calorimeter response at each stage of the signal evolution, from scintillation light to digitization. Calibration runs are monitored from a data quality perspective and u...

  7. Design, Construction and Calibration of a Near-Infrared Four-Color Pyrometry System for Laser-Driven High Pressure Experiments

    Science.gov (United States)

    Ali, S. J.; Jeanloz, R.; Collins, G.; Spaulding, D. K.

    2010-12-01

    Current dynamic compression experiments, using both quasi-isentropic and shock-compression, allow access to pressure-temperature states both on and off the principle Hugoniot and over a wide range of conditions of direct relevance to planetary interiors. Such studies necessitate reliable temperature measurements below 4000-5000 K. Such relatively low temperature states are also of particular interest for materials such as methane and water that do not experience much heating under shock compression. In order to measure these temperatures as a function of time across the sample, a four-color, near-infrared pyrometry system is being developed for use at the Janus laser facility (LLNL) with channels at wavelengths of 932nm-1008nm, 1008nm-1108nm, 1108nm-1208nm, and 1208nm-1300nm. Each color band is fiber-coupled to an InGaAs PIN photodiode with a rise time of less than 60 ps, read using an 18 GHz oscilloscope in order to ensure time resolutions of under 200 ps. This will allow for high temporal resolution measurements of laser-driven shock compression experiments with total durations of 5-15 ns as well as correlation with simultaneous time-resolved velocity interferometry and visual-wavelength pyrometry. Calibration of the system is being accomplished using quartz targets, as the EOS for quartz is well known, along with a calibrated integrating sphere of known spectral radiance.

  8. Towards terahertz detection and calibration through spontaneous parametric down-conversion in the terahertz idler-frequency range generated by a 795 nm diode laser system

    Directory of Open Access Journals (Sweden)

    Vladimir V. Kornienko

    2018-05-01

    Full Text Available We study a calibration scheme for terahertz wave nonlinear-optical detectors based on spontaneous parametric down-conversion. Contrary to the usual low wavelength pump in the green, we report here on the observation of spontaneous parametric down-conversion originating from an in-growth poled lithium niobate crystal pumped with a continuous wave 50 mW, 795 nm diode laser system, phase-matched to a terahertz frequency idler wave. Such a system is more compact and allows for longer poling periods as well as lower losses in the crystal. Filtering the pump radiation by a rubidium-87 vapor cell allowed the frequency-angular spectra to be obtained down to ∼0.5 THz or ∼1 nm shift from the pump radiation line. The presence of an amplified spontaneous emission “pedestal” in the diode laser radiation spectrum significantly hampers the observation of spontaneous parametric down-conversion spectra, in contrast to conventional narrowband gas lasers. Benefits of switching to longer pump wavelengths are pointed out, such as collinear optical-terahertz phase-matching in bulk crystals.

  9. Towards terahertz detection and calibration through spontaneous parametric down-conversion in the terahertz idler-frequency range generated by a 795 nm diode laser system

    Science.gov (United States)

    Kornienko, Vladimir V.; Kitaeva, Galiya Kh.; Sedlmeir, Florian; Leuchs, Gerd; Schwefel, Harald G. L.

    2018-05-01

    We study a calibration scheme for terahertz wave nonlinear-optical detectors based on spontaneous parametric down-conversion. Contrary to the usual low wavelength pump in the green, we report here on the observation of spontaneous parametric down-conversion originating from an in-growth poled lithium niobate crystal pumped with a continuous wave 50 mW, 795 nm diode laser system, phase-matched to a terahertz frequency idler wave. Such a system is more compact and allows for longer poling periods as well as lower losses in the crystal. Filtering the pump radiation by a rubidium-87 vapor cell allowed the frequency-angular spectra to be obtained down to ˜0.5 THz or ˜1 nm shift from the pump radiation line. The presence of an amplified spontaneous emission "pedestal" in the diode laser radiation spectrum significantly hampers the observation of spontaneous parametric down-conversion spectra, in contrast to conventional narrowband gas lasers. Benefits of switching to longer pump wavelengths are pointed out, such as collinear optical-terahertz phase-matching in bulk crystals.

  10. Gamma counter calibration system

    International Nuclear Information System (INIS)

    1977-01-01

    A method and apparatus are described for the calibration of a gamma radiation measurement instrument to be used over any of a number of different absolute energy ranges. The method includes the steps of adjusting the overall signal gain associated with pulses which are derived from detected gamma rays, until the instrument is calibrated for a particular absolute energy range; then storing parameter settings corresponding to the adjusted overall signal gain, and repeating the process for other desired absolute energy ranges. The stored settings can be subsequently retrieved and reapplied so that test measurements can be made using a selected one of the absolute energy ranges. Means are provided for adjusting the overall signal gain and a specific technique is disclosed for making coarse, then fine adjustments to the signal gain, for rapid convergence of the required calibration settings. (C.F.)

  11. ATLAS Tile calorimeter calibration and monitoring systems

    CERN Document Server

    Cortes-Gonzalez, Arely; The ATLAS collaboration

    2017-01-01

    The ATLAS Tile Calorimeter is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes, located in the outer part of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read out by two photomultiplier in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. The calibration system comprises Cesium radioactive sources, laser, charge injection elements and an integrator based readout system. Combined information from all systems allows to monitor and equalise the calorimeter r...

  12. ZY3-02 Laser Altimeter On-orbit Geometrical Calibration and Test

    Directory of Open Access Journals (Sweden)

    TANG Xinming

    2017-06-01

    Full Text Available ZY3-02 is the first satellite equipped with a laser altimeter for earth observation in China .This laser altimeter is an experimental payload for land elevation measurement experiment. The ranging and pointing bias of the laser altimeter would change due to the launch vibration, the space environment difference or other factors, and that could bring plane and elevation errors of laser altimeter. In this paper, we propose an on-orbit geometric calibration method using a ground-based electro-optical detection system based on the analysis of ZY3-02 laser altimeter characteristic, and this method constructs the rigorous geometric calibration model, which consider the pointing and ranging bias as unknown systematic errors, and the unknown parameters are calibrated with laser spot's location captured by laser detectors and the minimum ranging error principle. With the ALOS-DSM data as reference, the elevation accuracy of the laser altimeter can be improved from 100~150 meters before calibration to 2~3 meters after calibration when the terrain slope is less than 2 degree. With several ground control points obtained with RTK in laser footprint for validation, the absolute elevation precision of laser altimeter in the flat area can reach about 1 meter after the calibration. The test results demonstrated the effectiveness and feasibility of the proposed method.

  13. Microscope self-calibration based on micro laser line imaging and soft computing algorithms

    Science.gov (United States)

    Apolinar Muñoz Rodríguez, J.

    2018-06-01

    A technique to perform microscope self-calibration via micro laser line and soft computing algorithms is presented. In this technique, the microscope vision parameters are computed by means of soft computing algorithms based on laser line projection. To implement the self-calibration, a microscope vision system is constructed by means of a CCD camera and a 38 μm laser line. From this arrangement, the microscope vision parameters are represented via Bezier approximation networks, which are accomplished through the laser line position. In this procedure, a genetic algorithm determines the microscope vision parameters by means of laser line imaging. Also, the approximation networks compute the three-dimensional vision by means of the laser line position. Additionally, the soft computing algorithms re-calibrate the vision parameters when the microscope vision system is modified during the vision task. The proposed self-calibration improves accuracy of the traditional microscope calibration, which is accomplished via external references to the microscope system. The capability of the self-calibration based on soft computing algorithms is determined by means of the calibration accuracy and the micro-scale measurement error. This contribution is corroborated by an evaluation based on the accuracy of the traditional microscope calibration.

  14. ATLAS Tile calorimeter calibration and monitoring systems

    CERN Document Server

    Boumediene, Djamel Eddine; The ATLAS collaboration

    2017-01-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs). PMT signals are then digitized at 40 MHz and stored on detector and are only transferred off detector once the first level trigger acceptance has been confirmed. The readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read out by two PMTs in parallel. To calibrate and monitor the stability and performance of each part of the readout chain, a set of calibration systems is used. The TileCal calibration system comprises Cesium radioactive sources, laser, charge injection elements and an integrator b...

  15. ATLAS Tile calorimeter calibration and monitoring systems

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00445232; The ATLAS collaboration

    2016-01-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs), located on the outside of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read out by two PMTs in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. The TileCal calibration system comprises Cesium radioactive sources, laser and charge injection elements and it allows to monitor and equalize the calorimeter response at each stage of the signal production, from scin...

  16. ATLAS Tile calorimeter calibration and monitoring systems

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00445232; The ATLAS collaboration

    2017-01-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs), located on the outside of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read out by two PMTs in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. The TileCal calibration system comprises cesium radioactive sources, Laser and charge injection elements, and allows for monitoring and equalization of the calorimeter response at each stage of the signal production, ...

  17. Spectrophotometric calibration system for DECam

    Science.gov (United States)

    Rheault, J.-P.; DePoy, D. L.; Marshall, J. L.; Prochaska, T.; Allen, R.; Wise, J.; Martin, E.; Williams, P.

    2012-09-01

    We describe a spectrophotometric calibration system that is being implemented as part of the DES DECam project at the Blanco 4 meter at CTIO. Our calibration system uses a 1nm wide tunable source to measure the instrumental response function of the telescope optics and detector from 300nm up to 1100nm. This calibration will be performed regularly to monitor any change in the transmission function of the telescope during the 5 year survey. The system consists of a monochromator based tunable light source that provides illumination on a dome flat that is monitored by calibrated photodiodes that allow us to measure the telescope throughput as a function of wavelength. Our system has a peak output power of 2 mW, equivalent to a flux of approximately 800 photons/s/pixel on DECam.

  18. The KLOE online calibration system

    International Nuclear Information System (INIS)

    Pasqualucci, E.; Alexander, G.; Aloisio, A.

    2001-01-01

    Based on all the features of the KLOE online software, the online calibration system performs current calibration quality checking in real time and starts automatically new calibration procedures when needed. A calibration manager process controls the system, implementing the interface to the online system, receiving information from the run control and translating its state transitions to a separate state machine. It acts as a 'calibration run controller' and performs failure recovery when requested by a set of process checkers. The core of the system is a multi-threaded OO histogram server that receives histogramming commands by remote processes and operates on local ROOT histograms. A client library and C, fortran and C++ application interface libraries allow the user to connect and define his own histogram or read histograms owned by others using an book-like interface. Several calibration processes running in parallel in a distributed, multiplatform environment can fill the same histograms, allowing fast external information check. A monitor thread allow remote browsing for visual inspection. Pre-filtered data are read in non-privileged spy mode from the data acquisition system via the Kloe Integrated Dataflow. The main characteristics of the system are presented

  19. Electro-optical equivalent calibration technology for high-energy laser energy meters

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Ji Feng, E-mail: wjfcom2000@163.com [State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing 100084 (China); Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China); Graduate School of China Academy of Engineering Physics, Beijing 100088 (China); Key Laboratory of Laser Science and Technology, China Academy of Engineering Physics, Mianyang 621900 (China); Chang, Yan; Zhang, Kai; Hu, Xiao Yang; Zhang, Wei [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China); Key Laboratory of Laser Science and Technology, China Academy of Engineering Physics, Mianyang 621900 (China); Sun, Li Qun [State Key Laboratory of Precision Measurement Technology and Instrument, Tsinghua University, Beijing 100084 (China)

    2016-04-15

    Electro-optical equivalent calibration with high calibration power and high equivalence is particularly well-suited to the calibration of high-energy laser energy meters. A large amount of energy is reserved during this process, however, which continues to radiate after power-off. This study measured the radiation efficiency of a halogen tungsten lamp during power-on and after power-off in order to calculate the total energy irradiated by a lamp until the high-energy laser energy meter reaches thermal equilibrium. A calibration system was designed based on the measurement results, and the calibration equivalence of the system was analyzed in detail. Results show that measurement precision is significantly affected by the absorption factor of the absorption chamber and by heat loss in the energy meter. Calibration precision is successfully improved by enhancing the equivalent power and reducing power-on time. The electro-optical equivalent calibration system, measurement uncertainty of which was evaluated as 2.4% (k = 2), was used to calibrate a graphite-cone-absorption-cavity absolute energy meter, yielding a calibration coefficient of 1.009 and measurement uncertainty of 3.5% (k = 2). A water-absorption-type high-energy laser energy meter with measurement uncertainty of 4.8% (k = 2) was considered the reference standard, and compared to the energy meter calibrated in this study, yielded a correction factor of 0.995 (standard deviation of 1.4%).

  20. Fiber optic neutron imaging system: calibration

    International Nuclear Information System (INIS)

    Malone, R.M.; Gow, C.E.; Thayer, D.R.

    1981-01-01

    Two neutron imaging experiments using fiber optics have been performed at the Nevada Test Site. In each experiment, an array of scintillator fluor tubes is exposed to neutrons. Light is coupled out through radiation resistant PCS fibers (8-m long) into high-bandwidth, graded index fibers. For image reconstruction to be accurate, common timing differences and transmission variations between fiber optic channels are needed. The calibration system featured a scanning pulsed dye laser, a specially designed fiber optic star coupler, a tektronix 7912AD transient digitizer, and a DEC PDP 11/34 computing system

  1. ATLAS Tile Calorimeter calibration and monitoring systems

    Science.gov (United States)

    Cortés-González, Arely

    2018-01-01

    The ATLAS Tile Calorimeter is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes, located in the outer part of the calorimeter. Neutral particles may also produce a signal after interacting with the material and producing charged particles. The readout is segmented into about 5000 cells, each of them being read out by two photomultipliers in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. This comprises Cesium radioactive sources, Laser, charge injection elements and an integrator based readout system. Information from all systems allows to monitor and equalise the calorimeter response at each stage of the signal production, from scintillation light to digitisation. Calibration runs are monitored from a data quality perspective and used as a cross-check for physics runs. The data quality efficiency achieved during 2016 was 98.9%. These calibration and stability of the calorimeter reported here show that the TileCal performance is within the design requirements and has given essential contribution to reconstructed objects and physics results.

  2. ATLAS Tile calorimeter calibration and monitoring systems

    Science.gov (United States)

    Chomont, Arthur; ATLAS Collaboration

    2017-11-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs), located on the outside of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read out by two PMTs in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. The TileCal calibration system comprises cesium radioactive sources, Laser and charge injection elements, and allows for monitoring and equalization of the calorimeter response at each stage of the signal production, from scintillation light to digitization. Based on LHC Run 1 experience, several calibration systems were improved for Run 2. The lessons learned, the modifications, and the current LHC Run 2 performance are discussed.

  3. High power lasers & systems

    OpenAIRE

    Chatwin, Chris; Young, Rupert; Birch, Philip

    2015-01-01

    Some laser history;\\ud Airborne Laser Testbed & Chemical Oxygen Iodine Laser (COIL);\\ud Laser modes and beam propagation;\\ud Fibre lasers and applications;\\ud US Navy Laser system – NRL 33kW fibre laser;\\ud Lockheed Martin 30kW fibre laser;\\ud Conclusions

  4. X-ray calibration facility for plasma diagnostics of the MegaJoule laser

    International Nuclear Information System (INIS)

    Hubert, S.; Prevot, V.

    2013-01-01

    The Laser MegaJoule (LMJ) located at CEA-CESTA will be equipped with x-ray plasma diagnostics using different kinds of x-ray components such as filters, mirrors, crystals, detectors and cameras. To guarantee LMJ measurements, detectors such as x-ray cameras need to be regularly calibrated. An x-ray laboratory is devoted to this task and performs absolute x-ray calibrations for similar x-ray cameras running on Laser Integration Line (LIL). This paper presents the x-ray calibration bench with its x-ray tube based High Energy x-ray Source (HEXS) and some calibration results. By mean of an ingenious transposition system under vacuum absolute x-ray calibration of x-ray cameras, like streak and stripline ones, can be carried out. Coupled to a new collimation system with micrometric accuracy on aperture sensitivity quantum efficiency measurements can be achieved with reduced uncertainties. (authors)

  5. Optogalvanic wavelength calibration for laser monitoring of reactive atmospheric species

    Science.gov (United States)

    Webster, C. R.

    1982-01-01

    Laser-based techniques have been successfully employed for monitoring atmospheric species of importance to stratospheric ozone chemistry or tropospheric air quality control. When spectroscopic methods using tunable lasers are used, a simultaneously recorded reference spectrum is required for wavelength calibration. For stable species this is readily achieved by incorporating into the sensing instrument a reference cell containing the species to be monitored. However, when the species of interest is short-lived, this approach is unsuitable. It is proposed that wavelength calibration for short-lived species may be achieved by generating the species of interest in an electrical or RF discharge and using optogalvanic detection as a simple, sensitive, and reliable means of recording calibration spectra. The wide applicability of this method is emphasized. Ultraviolet, visible, or infrared lasers, either CW or pulsed, may be used in aircraft, balloon, or shuttle experiments for sensing atoms, molecules, radicals, or ions.

  6. Calibration of ALIBAVA readout system

    Energy Technology Data Exchange (ETDEWEB)

    Trofymov, Artur [DESY, Hamburg (Germany); Collaboration: ATLAS experiment-Collaboration

    2015-07-01

    The High Luminosity Large Hadron Collider (LH-LHC) is the upgrade of the LHC that foreseen to increase the instantaneous luminosity by a factor ten with a total integrated luminosity of 3000 fb{sup -1}. The ATLAS experiment will need to build a new tracker to operate in the new severe LH-LHC conditions (increasing detector granularity to cope with much higher channel occupancy, designing radiation-hard sensors and electronics to cope with radiation damage). Charge collection efficiency (CCE) of silicon strip sensors for the new ATLAS tracker can be done with ALIBAVA analog readout system (analog system gives more information about signal from all strips than digital). In this work the preliminary results of ALIBAVA calibration using two different methods (with ''source data'' and ''calibration data'') are presented. Calibration constant obtained by these methods is necessary for knowing collected charge on the silicon strip sensors and for having the ability to compare it with measurements done at the test beam.

  7. Calibration-free laser-induced breakdown spectroscopy for ...

    Indian Academy of Sciences (India)

    journal of. August 2012 physics pp. 299–310. Calibration-free laser-induced ... for quantitative analysis of materials, illustrated by CF-LIBS applied to a ..... The authors are thankful to BRNS, DAE, Govt. of India for the financial support provided.

  8. Novel xenon calibration scheme for two-photon absorption laser induced fluorescence of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Drew; Scime, Earl; Short, Zachary, E-mail: zdshort@mix.wvu.edu [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26056 (United States)

    2016-11-15

    Two photon absorption laser induced fluorescence (TALIF) measurements of neutral hydrogen and its isotopes are typically calibrated by performing TALIF measurements on krypton with the same diagnostic system and using the known ratio of the absorption cross sections [K. Niemi et al., J. Phys. D 34, 2330 (2001)]. Here we present the measurements of a new calibration method based on a ground state xenon scheme for which the fluorescent emission wavelength is nearly identical to that of hydrogen, thereby eliminating chromatic effects in the collection optics and simplifying detector calibration. We determine that the ratio of the TALIF cross sections of xenon and hydrogen is 0.024 ± 0.001.

  9. Extrinsic Calibration of Camera and 2D Laser Sensors without Overlap

    Directory of Open Access Journals (Sweden)

    Khalil M. Ahmad Yousef

    2017-10-01

    Full Text Available Extrinsic calibration of a camera and a 2D laser range finder (lidar sensors is crucial in sensor data fusion applications; for example SLAM algorithms used in mobile robot platforms. The fundamental challenge of extrinsic calibration is when the camera-lidar sensors do not overlap or share the same field of view. In this paper we propose a novel and flexible approach for the extrinsic calibration of a camera-lidar system without overlap, which can be used for robotic platform self-calibration. The approach is based on the robot–world hand–eye calibration (RWHE problem; proven to have efficient and accurate solutions. First, the system was mapped to the RWHE calibration problem modeled as the linear relationship AX = ZB , where X and Z are unknown calibration matrices. Then, we computed the transformation matrix B , which was the main challenge in the above mapping. The computation is based on reasonable assumptions about geometric structure in the calibration environment. The reliability and accuracy of the proposed approach is compared to a state-of-the-art method in extrinsic 2D lidar to camera calibration. Experimental results from real datasets indicate that the proposed approach provides better results with an L2 norm translational and rotational deviations of 314 mm and 0 . 12 ∘ respectively.

  10. Extrinsic Calibration of Camera and 2D Laser Sensors without Overlap.

    Science.gov (United States)

    Ahmad Yousef, Khalil M; Mohd, Bassam J; Al-Widyan, Khalid; Hayajneh, Thaier

    2017-10-14

    Extrinsic calibration of a camera and a 2D laser range finder (lidar) sensors is crucial in sensor data fusion applications; for example SLAM algorithms used in mobile robot platforms. The fundamental challenge of extrinsic calibration is when the camera-lidar sensors do not overlap or share the same field of view. In this paper we propose a novel and flexible approach for the extrinsic calibration of a camera-lidar system without overlap, which can be used for robotic platform self-calibration. The approach is based on the robot-world hand-eye calibration (RWHE) problem; proven to have efficient and accurate solutions. First, the system was mapped to the RWHE calibration problem modeled as the linear relationship AX = ZB , where X and Z are unknown calibration matrices. Then, we computed the transformation matrix B , which was the main challenge in the above mapping. The computation is based on reasonable assumptions about geometric structure in the calibration environment. The reliability and accuracy of the proposed approach is compared to a state-of-the-art method in extrinsic 2D lidar to camera calibration. Experimental results from real datasets indicate that the proposed approach provides better results with an L2 norm translational and rotational deviations of 314 mm and 0 . 12 ∘ respectively.

  11. Towards Robust Self-Calibration for Handheld 3d Line Laser Scanning

    Science.gov (United States)

    Bleier, M.; Nüchter, A.

    2017-11-01

    This paper studies self-calibration of a structured light system, which reconstructs 3D information using video from a static consumer camera and a handheld cross line laser projector. Intersections between the individual laser curves and geometric constraints on the relative position of the laser planes are exploited to achieve dense 3D reconstruction. This is possible without any prior knowledge of the movement of the projector. However, inaccurrately extracted laser lines introduce noise in the detected intersection positions and therefore distort the reconstruction result. Furthermore, when scanning objects with specular reflections, such as glossy painted or metalic surfaces, the reflections are often extracted from the camera image as erroneous laser curves. In this paper we investiagte how robust estimates of the parameters of the laser planes can be obtained despite of noisy detections.

  12. Absolute calibration in vivo measurement systems

    International Nuclear Information System (INIS)

    Kruchten, D.A.; Hickman, D.P.

    1991-02-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs

  13. Calibration method for a radwaste assay system

    International Nuclear Information System (INIS)

    Dulama, C.; Dobrin, R.; Toma, Al.; Paunoiu, C.

    2004-01-01

    A waste assay system entirely designed and manufactured in the Institute for Nuclear Research is used in radwaste treatment and conditioning stream to ensure compliance with national repository radiological requirements. Usually, waste assay systems are calibrated by using various experimental arrangements including calibration phantoms. The paper presents a comparative study concerning the efficiency calibration performed by shell source method and a semiempirical, computational method based on a Monte Carlo algorithm. (authors)

  14. On the possiblity of using vertically pointing Central Laser Facilities to calibrate the Cherenkov Telescope Array

    International Nuclear Information System (INIS)

    Gaug, Markus

    2014-01-01

    A Central Laser Facility is a system composed of a laser placed at a certain distance from a light-detector array, emitting fast light pulses, typically in the vertical direction, with the aim to calibrate that array. During calibration runs, all detectors are pointed towards the same portion of the laser beam at a given altitude. Central Laser Facilities are used for various currently operating ultra-high-energy cosmic ray and imaging atmospheric Cherenkov telescope arrays. In view of the future Cherenkov Telescope Array, a similar device could provide a fast calibration of the whole installation at different wavelengths. The relative precision (i.e. each individual telescope with respect to the rest of the array is expected) to be better than 5%, while an absolute calibration should reach a precisions of 6–11%, if certain design requirements are met. Additionally, a preciser monitoring of the sensitivity of each telescope can be made on time-scales of days to years

  15. A three-dimensional laser vibration measurement technology realized on five laser beam and its calibration

    Science.gov (United States)

    Li, Lu-Ke; Zhang, Shen-Feng

    2018-03-01

    Put forward a kind of three-dimensional vibration information technology of vibrating object by the mean of five laser beam of He-Ne laser, and with the help of three-way sensor, measure the three-dimensional laser vibration developed by above mentioned technology. The technology based on the Doppler principle of interference and signal demodulation technology, get the vibration information of the object, through the algorithm processing, extract the three-dimensional vibration information of space objects, and can achieve the function of angle calibration of five beam in the space, which avoid the effects of the mechanical installation error, greatly improve the accuracy of measurement. With the help of a & B K4527 contact three axis sensor, measure and calibrate three-dimensional laser vibrometer, which ensure the accuracy of the measurement data. Summarize the advantages and disadvantages of contact and non-contact sensor, and analysis the future development trends of the sensor industry.

  16. Radiation energy calibrating system and method

    International Nuclear Information System (INIS)

    Jacobson, A.F.

    1980-01-01

    A radiation energy calibrating system and method which uses a pair of calibrated detectors for measurements of radiation intensity from x-ray tubes for a non-invasive determination of the electrical characteristics; I.E., the tube potential and/or current

  17. The Laser calibration of the ATLAS Tile Calorimeter during the LHC run 1

    CERN Document Server

    INSPIRE-00305555

    2016-10-12

    This article describes the Laser calibration system of the Atlas hadronic Tile Calorimeter that has been used during the run 1 of the LHC. First, the stability of the system associated readout electronics is studied. It is found to be stable with variations smaller than 0.6 %. Then, the method developed to compute the calibration constants, to correct for the variations of the gain of the calorimeter photomultipliers, is described. These constants were determined with a statistical uncertainty of 0.3 % and a systematic uncertainty of 0.2 % for the central part of the calorimeter and 0.5 % for the end-caps. Finally, the detection and correction of timing mis-configuration of the Tile Calorimeter using the Laser system are also presented.

  18. A water flow calorimeter calibration system

    International Nuclear Information System (INIS)

    Ullrich, F.T.

    1983-01-01

    Neutral beam systems are instrumented by several water flow calorimeter systems, and some means is needed to verify the accuracy of such systems and diagnose their failures. This report describes a calibration system for these calorimeters. The calibrator consists of two 24 kilowatt circulation water heaters, with associated controls and instrumentation. The unit can supply power from 0 to 48 kW in five coarse steps and one fine range. Energy is controlled by varying the power and the time of operation of the heaters. The power is measured by means of precision power transducers, and the energy is measured by integrating the power with respect to time. The accuracy of the energy measurement is better than 0.5% when the power supplied is near full scale, and the energy resolution is better than 1 kilojoule. The maximum energy delivered is approximately 50 megajoules. The calorimetry loop to be calibrated is opened, and the calibrator is put in series with the calorimeter heat source. The calorimeter is then operated in its normal fashion, with the calibrator used as the heat source. The calibrator can also be used in a stand alone mode to calibrate calorimeter sensors removed from systems

  19. Laser cutting system

    Science.gov (United States)

    Dougherty, Thomas J

    2015-03-03

    A workpiece cutting apparatus includes a laser source, a first suction system, and a first finger configured to guide a workpiece as it moves past the laser source. The first finger includes a first end provided adjacent a point where a laser from the laser source cuts the workpiece, and the first end of the first finger includes an aperture in fluid communication with the first suction system.

  20. Automated system for the calibration of magnetometers

    DEFF Research Database (Denmark)

    Petrucha, Vojtech; Kaspar, Petr; Ripka, Pavel

    2009-01-01

    A completely nonmagnetic calibration platform has been developed and constructed at DTU Space (Technical University of Denmark). It is intended for on-site scalar calibration of high-precise fluxgate magnetometers. An enhanced version of the same platform is being built at the Czech Technical Uni...... through custom-made optical incremental sensors. The system is controlled by a microcontroller, which executes commands from a computer. The properties of the system as well as calibration and measurement results will be presented. ©2009 American Institute of Physics...

  1. DECal: A Spectrophotometric Calibration System For DECam.

    Science.gov (United States)

    Rheault, Jean-Philippe; DePoy, D. L.; Marshall, J. L.; Prochaska, T.; Allen, R.; Wise, J.; Martin, E.

    2012-01-01

    We present preliminary results for a spectrophotometric calibration system that is being implemented as part of the DES DECam project at the Blanco 4 meter at CTIO. Our calibration system uses a 2nm wide tunable source to measure the instrumental response function of the telescope from 300nm up to 1100nm. This calibration will be performed regularly to monitor any change in the transmission function. The system consists of a monochromator based tunable light source that provides illumination on a dome flat that is monitored by calibrated photodiodes and allow us to measure the throughput as a function of wavelength. Our system has an output power of 2 mW, equivalent to a flux of approximately 800 photons/s/pixel on DECam. Preliminary results of the measure of the throughput of the telescope will be presented.

  2. Systems and methods of eye tracking calibration

    DEFF Research Database (Denmark)

    2014-01-01

    Methods and systems to facilitate eye tracking control calibration are provided. One or more objects are displayed on a display of a device, where the one or more objects are associated with a function unrelated to a calculation of one or more calibration parameters. The one or more calibration...... parameters relate to a calibration of a calculation of gaze information of a user of the device, where the gaze information indicates where the user is looking. While the one or more objects are displayed, eye movement information associated with the user is determined, which indicates eye movement of one...... or more eye features associated with at least one eye of the user. The eye movement information is associated with a first object location of the one or more objects. The one or more calibration parameters are calculated based on the first object location being associated with the eye movement information....

  3. PFN tool test and calibration system

    International Nuclear Information System (INIS)

    Stephenson, W.A.

    1981-12-01

    A system has been developed for the functional testing and neutron output calibration of the PFN (Prompt Fission Neutron) Uranium Logging Tool. The system was designed primarily for field work and consists of a special vehicle as well as test apparatus. Only the pertinent instrumentation is described. This document will serve as an Instruction and Test Equipment service manual for those involved with calibration of the neutron output of the PFN tool

  4. Infrared laser system

    International Nuclear Information System (INIS)

    Cantrell, C.D.; Carbone, R.J.

    1977-01-01

    An infrared laser system and method for isotope separation may comprise a molecular gas laser oscillator to produce a laser beam at a first wavelength, Raman spin flip means for shifting the laser to a second wavelength, a molecular gas laser amplifier to amplify said second wavelength laser beam to high power, and optical means for directing the second wavelength, high power laser beam against a desired isotope for selective excitation thereof in a mixture with other isotopes. The optical means may include a medium which shifts the second wavelength high power laser beam to a third wavelength, high power laser beam at a wavelength coincidental with a corresponding vibrational state of said isotope and which is different from vibrational states of other isotopes in the gas mixture

  5. Robot-laser system

    International Nuclear Information System (INIS)

    Akeel, H.A.

    1987-01-01

    A robot-laser system is described for providing a laser beam at a desired location, the system comprising: a laser beam source; a robot including a plurality of movable parts including a hollow robot arm having a central axis along which the laser source directs the laser beam; at least one mirror for reflecting the laser beam from the source to the desired location, the mirror being mounted within the robot arm to move therewith and relative thereto to about a transverse axis that extends angularly to the central axis of the robot arm; and an automatic programmable control system for automatically moving the mirror about the transverse axis relative to and in synchronization with movement of the robot arm to thereby direct the laser beam to the desired location as the arm is moved

  6. Computerized 50 liter volume calibration system

    International Nuclear Information System (INIS)

    Proffitt, T.H.

    1990-01-01

    A system has been designed for the Savannah River Site that will be used to calibrate product shipping containers. For accountability purposes, it is necessary that these containers be calibrated to a very high precision. The Computerized 50 Liter Volume Calibration System (CVCS), which is based on the Ideal Gas Law (IGL), will use reference volumes with precision of no less ±0.03%, and helium to calibrate the containers to have a total error of no greater than ±0.10%. A statistical interpretation of the system has given a theoretical total calculated error of ±0.08%. Tests with the system will be performed once fabrication is complete to experimentally verify the calculated error. Since the total error was calculated using the worst case scenario, the actual error should be significantly less than the calculated value. The computer controlled, totally automated system is traceable to the National Institute of Standards and Technology. The design, calibration procedure, and statistical interpretation of the system will be discussed. 1 ref

  7. ARGOS laser system mechanical design

    Science.gov (United States)

    Deysenroth, M.; Honsberg, M.; Gemperlein, H.; Ziegleder, J.; Raab, W.; Rabien, S.; Barl, L.; Gässler, W.; Borelli, J. L.

    2014-07-01

    ARGOS, a multi-star adaptive optics system is designed for the wide-field imager and multi-object spectrograph LUCI on the LBT (Large Binocular Telescope). Based on Rayleigh scattering the laser constellation images 3 artificial stars (at 532 nm) per each of the 2 eyes of the LBT, focused at a height of 12 km (Ground Layer Adaptive Optics). The stars are nominally positioned on a circle 2' in radius, but each star can be moved by up to 0.5' in any direction. For all of these needs are following main subsystems necessary: 1. A laser system with its 3 Lasers (Nd:YAG ~18W each) for delivering strong collimated light as for LGS indispensable. 2. The Launch system to project 3 beams per main mirror as a 40 cm telescope to the sky. 3. The Wave Front Sensor with a dichroic mirror. 4. The dichroic mirror unit to grab and interpret the data. 5. A Calibration Unit to adjust the system independently also during day time. 6. Racks + platforms for the WFS units. 7. Platforms and ladders for a secure access. This paper should mainly demonstrate how the ARGOS Laser System is configured and designed to support all other systems.

  8. Calibrating airborne measurements of airspeed, pressure and temperature using a Doppler laser air-motion sensor

    Directory of Open Access Journals (Sweden)

    W. A. Cooper

    2014-09-01

    Full Text Available A new laser air-motion sensor measures the true airspeed with a standard uncertainty of less than 0.1 m s−1 and so reduces uncertainty in the measured component of the relative wind along the longitudinal axis of the aircraft to about the same level. The calculated pressure expected from that airspeed at the inlet of a pitot tube then provides a basis for calibrating the measurements of dynamic and static pressure, reducing standard uncertainty in those measurements to less than 0.3 hPa and the precision applicable to steady flight conditions to about 0.1 hPa. These improved measurements of pressure, combined with high-resolution measurements of geometric altitude from the global positioning system, then indicate (via integrations of the hydrostatic equation during climbs and descents that the offset and uncertainty in temperature measurement for one research aircraft are +0.3 ± 0.3 °C. For airspeed, pressure and temperature, these are significant reductions in uncertainty vs. those obtained from calibrations using standard techniques. Finally, it is shown that although the initial calibration of the measured static and dynamic pressures requires a measured temperature, once calibrated these measured pressures and the measurement of airspeed from the new laser air-motion sensor provide a measurement of temperature that does not depend on any other temperature sensor.

  9. Use of Naturally Available Reference Targets to Calibrate Airborne Laser Scanning Intensity Data

    Directory of Open Access Journals (Sweden)

    Paula Litkey

    2009-04-01

    Full Text Available We have studied the possibility of calibrating airborne laser scanning (ALS intensity data, using land targets typically available in urban areas. For this purpose, a test area around Espoonlahti Harbor, Espoo, Finland, for which a long time series of ALS campaigns is available, was selected. Different target samples (beach sand, concrete, asphalt, different types of gravel were collected and measured in the laboratory. Using tarps, which have certain backscattering properties, the natural samples were calibrated and studied, taking into account the atmospheric effect, incidence angle and flying height. Using data from different flights and altitudes, a time series for the natural samples was generated. Studying the stability of the samples, we could obtain information on the most ideal types of natural targets for ALS radiometric calibration. Using the selected natural samples as reference, the ALS points of typical land targets were calibrated again and examined. Results showed the need for more accurate ground reference data, before using natural samples in ALS intensity data calibration. Also, the NIR camera-based field system was used for collecting ground reference data. This system proved to be a good means for collecting in situ reference data, especially for targets with inhomogeneous surface reflection properties.

  10. Laser transmitter system

    International Nuclear Information System (INIS)

    Dye, R.A.

    1975-01-01

    A laser transmitter system is disclosed which utilizes mechanical energy for generating an output pulse. The laser system includes a current developing device such as a piezoelectric crystal which charges a storage device such as a capacitor in response to a mechanical input signal. The capacitor is coupled to a switching device, such as a silicon controlled rectifier (SCR). The switching device is coupled to a laser transmitter such as a GaAs laser diode, which provides an output signal in response to the capacitor being discharged

  11. Shiva laser system performance

    International Nuclear Information System (INIS)

    Glaze, J.; Godwin, R.O.; Holzrichter, J.F.

    1978-01-01

    On November 18, 1977, after four years of experimentation, innovation, and construction, the Shiva High Energy Laser facility produced 10.2 kJ of focusable laser energy delivered in a 0.95 ns pulse. The Shiva laser, with its computer control system and delta amplifiers, demonstrated its versatility on May 18, 1978, when the first 20-beam target shot with delta amplifiers focused 26 TW on a target and produced a yield of 7.5 x 10 9 neutrons

  12. Powering laser diode systems

    CERN Document Server

    Trestman, Grigoriy A

    2017-01-01

    This Tutorial Text discusses the competent design and skilled use of laser diode drivers (LDDs) and power supplies (PSs) for the electrical components of laser diode systems. It is intended to help power-electronic design engineers during the initial design stages: the choice of the best PS topology, the calculation of parameters and components of the PS circuit, and the computer simulation of the circuit. Readers who use laser diode systems for research, production, and other purposes will also benefit. The book will help readers avoid errors when creating laser systems from ready-made blocks, as well as understand the nature of the "mystical failures" of laser diodes (and possibly prevent them).

  13. An absolute calibration system for millimeter-accuracy APOLLO measurements

    Science.gov (United States)

    Adelberger, E. G.; Battat, J. B. R.; Birkmeier, K. J.; Colmenares, N. R.; Davis, R.; Hoyle, C. D.; Huang, L. R.; McMillan, R. J.; Murphy, T. W., Jr.; Schlerman, E.; Skrobol, C.; Stubbs, C. W.; Zach, A.

    2017-12-01

    Lunar laser ranging provides a number of leading experimental tests of gravitation—important in our quest to unify general relativity and the standard model of physics. The apache point observatory lunar laser-ranging operation (APOLLO) has for years achieved median range precision at the  ∼2 mm level. Yet residuals in model-measurement comparisons are an order-of-magnitude larger, raising the question of whether the ranging data are not nearly as accurate as they are precise, or if the models are incomplete or ill-conditioned. This paper describes a new absolute calibration system (ACS) intended both as a tool for exposing and eliminating sources of systematic error, and also as a means to directly calibrate ranging data in situ. The system consists of a high-repetition-rate (80 MHz) laser emitting short (motivating continued work on model capabilities. The ACS provides the means to deliver APOLLO data both accurate and precise below the 2 mm level.

  14. Automated system for the calibration of magnetometers

    International Nuclear Information System (INIS)

    Petrucha, Vojtech; Kaspar, Petr; Ripka, Pavel; Merayo, Jose M. G.

    2009-01-01

    A completely nonmagnetic calibration platform has been developed and constructed at DTU Space (Technical University of Denmark). It is intended for on-site scalar calibration of high-precise fluxgate magnetometers. An enhanced version of the same platform is being built at the Czech Technical University. There are three axes of rotation in this design (compared to two axes in the previous version). The addition of the third axis allows us to calibrate more complex devices. An electronic compass based on a vector fluxgate magnetometer and micro electro mechanical systems (MEMS) accelerometer is one example. The new platform can also be used to evaluate the parameters of the compass in all possible variations in azimuth, pitch, and roll. The system is based on piezoelectric motors, which are placed on a platform made of aluminum, brass, plastic, and glass. Position sensing is accomplished through custom-made optical incremental sensors. The system is controlled by a microcontroller, which executes commands from a computer. The properties of the system as well as calibration and measurement results will be presented

  15. Independent System Calibration of Sentinel-1B

    Directory of Open Access Journals (Sweden)

    Marco Schwerdt

    2017-05-01

    Full Text Available Sentinel-1B is the second of two C-Band Synthetic Aperture Radar (SAR satellites of the Sentinel-1 mission, launched in April 2016—two years after the launch of the first satellite, Sentinel-1A. In addition to the commissioning of Sentinel-1B executed by the European Space Agency (ESA, an independent system calibration was performed by the German Aerospace Center (DLR on behalf of ESA. Based on an efficient calibration strategy and the different calibration procedures already developed and applied for Sentinel-1A, extensive measurement campaigns were executed by initializing and aligning DLR’s reference targets deployed on the ground. This paper describes the different activities performed by DLR during the Sentinel-1B commissioning phase and presents the results derived from the analysis and the evaluation of a multitude of data takes and measurements.

  16. Laser Megajoule synchronization system

    International Nuclear Information System (INIS)

    Luttmann, M.; Pastor, J.F; Drouet, V.; Prat, M.; Raimbourg, J.; Adolf, A.

    2011-01-01

    This paper describes the synchronisation system under development on the Laser Megajoule (LMJ) in order to synchronize the laser quads on the target to better than 40 ps rms. Our architecture is based on a Timing System (TS) which delivers trigger signals with jitter down to 15 ps rms coupled with an ultra precision timing system with 5 ps rms jitter. In addition to TS, a sensor placed at the target chamber center measures the arrival times of the 3 omega nano joule laser pulses generated by front end shots. (authors)

  17. Joint Calibration of 3d Laser Scanner and Digital Camera Based on Dlt Algorithm

    Science.gov (United States)

    Gao, X.; Li, M.; Xing, L.; Liu, Y.

    2018-04-01

    Design a calibration target that can be scanned by 3D laser scanner while shot by digital camera, achieving point cloud and photos of a same target. A method to joint calibrate 3D laser scanner and digital camera based on Direct Linear Transformation algorithm was proposed. This method adds a distortion model of digital camera to traditional DLT algorithm, after repeating iteration, it can solve the inner and external position element of the camera as well as the joint calibration of 3D laser scanner and digital camera. It comes to prove that this method is reliable.

  18. The Calibration System of the E989 Experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Anastasi, Antonio [Univ. of Messina (Italy)

    2017-01-01

    The muon anomaly aµ is one of the most precise quantity known in physics experimentally and theoretically. The high level of accuracy permits to use the measurement of aµ as a test of the Standard Model comparing with the theoretical calculation. After the impressive result obtained at Brookhaven National Laboratory in 2001 with a total accuracy of 0.54 ppm, a new experiment E989 is under construction at Fermilab, motivated by the diff of aexp SM µ - aµ ~ 3σ. The purpose of the E989 experiment is a fourfold reduction of the error, with a goal of 0.14 ppm, improving both the systematic and statistical uncertainty. With the use of the Fermilab beam complex a statistic of × 21 with respect to BNL will be reached in almost 2 years of data taking improving the statistical uncertainty to 0.1 ppm. Improvement on the systematic error involves the measurement technique of ωa and ωp, the anomalous precession frequency of the muon and the Larmor precession frequency of the proton respectively. The measurement of ωp involves the magnetic field measurement and improvements on this sector related to the uniformity of the field should reduce the systematic uncertainty with respect to BNL from 170 ppb to 70 ppb. A reduction from 180 ppb to 70 ppb is also required for the measurement of ωa; new DAQ, a faster electronics and new detectors and calibration system will be implemented with respect to E821 to reach this goal. In particular the laser calibration system will reduce the systematic error due to gain fl of the photodetectors from 0.12 to 0.02 ppm. The 0.02 ppm limit on systematic requires a system with a stability of 10-4 on short time scale (700 µs) while on longer time scale the stability is at the percent level. The 10-4 stability level required is almost an order of magnitude better than the existing laser calibration system in particle physics, making the calibration system a very challenging item. In addition to the high level

  19. Real-time dynamic calibration of a tunable frequency laser source using a Fabry-Pérot interferometer

    Energy Technology Data Exchange (ETDEWEB)

    Mandula, Gábor, E-mail: mandula.gabor@wigner.mta.hu; Kis, Zsolt; Lengyel, Krisztián [Wigner Research Centre for Physics of the Hungarian Academy of Sciences, Konkoly-Thege Miklós út 29-33, H-1121 Budapest (Hungary)

    2015-12-15

    We report on a method for real-time dynamic calibration of a tunable external cavity diode laser by using a partially mode-matched plano-concave Fabry-Pérot interferometer in reflection geometry. Wide range laser frequency scanning is carried out by piezo-driven tilting of a diffractive grating playing the role of a frequency selective mirror in the laser cavity. The grating tilting system has a considerable mechanical inertness, so static laser frequency calibration leads to false results. The proposed real-time dynamic calibration based on the identification of primary- and Gouy-effect type secondary interference peaks with known frequency and temporal history can be used for a wide scanning range (from 0.2 GHz to more than 1 GHz). A concave spherical mirror with a radius of R = 100 cm and a plain 1% transmitting mirror was used as a Fabry-Pérot interferometer with various resonator lengths to investigate and demonstrate real-time calibration procedures for two kinds of laser frequency scanning functions.

  20. Rapid calibrated high-resolution hyperspectral imaging using tunable laser source

    Science.gov (United States)

    Nguyen, Lam K.; Margalith, Eli

    2009-05-01

    We present a novel hyperspectral imaging technique based on tunable laser technology. By replacing the broadband source and tunable filters of a typical NIR imaging instrument, several advantages are realized, including: high spectral resolution, highly variable field-of-views, fast scan-rates, high signal-to-noise ratio, and the ability to use optical fiber for efficient and flexible sample illumination. With this technique, high-resolution, calibrated hyperspectral images over the NIR range can be acquired in seconds. The performance of system features will be demonstrated on two example applications: detecting melamine contamination in wheat gluten and separating bovine protein from wheat protein in cattle feed.

  1. Absolute calibration of a time-of-flight spectrometer and imaging plate for the characterization of laser-accelerated protons

    International Nuclear Information System (INIS)

    Choi, I W; Kim, C M; Sung, J H; Kim, I J; Yu, T J; Lee, S K; Jin, Y-Y; Pae, K H; Hafz, N; Lee, J

    2009-01-01

    A proton energy spectrometer system is composed of a time-of-flight spectrometer (TOFS) and a Thomson parabola spectrometer (TPS), and is used to characterize laser-accelerated protons. The TOFS detects protons with a plastic scintillator, and the TPS with a CR-39 or imaging plate (IP). The two spectrometers can operate simultaneously and give separate time-of-flight (TOF) and Thomson parabola (TP) data. We propose a method to calibrate the TOFS and IP by comparing the TOF data and the TP data taken with CR-39 and IP. The absolute response of the TOFS as a function of proton energy is calculated from the proton number distribution measured with CR-39. The sensitivity of IP to protons is obtained from the proton number distribution estimated with the calibrated TOFS. This method, based on the comparison of the simultaneously measured data, gives more reliable results when using laser-accelerated protons as a calibration source. The calibrated spectrometer system can be used to measure absolutely calibrated energy spectra for the optimization of laser-accelerated protons

  2. Computer Generated Hologram System for Wavefront Measurement System Calibration

    Science.gov (United States)

    Olczak, Gene

    2011-01-01

    Computer Generated Holograms (CGHs) have been used for some time to calibrate interferometers that require nulling optics. A typical scenario is the testing of aspheric surfaces with an interferometer placed near the paraxial center of curvature. Existing CGH technology suffers from a reduced capacity to calibrate middle and high spatial frequencies. The root cause of this shortcoming is as follows: the CGH is not placed at an image conjugate of the asphere due to limitations imposed by the geometry of the test and the allowable size of the CGH. This innovation provides a calibration system where the imaging properties in calibration can be made comparable to the test configuration. Thus, if the test is designed to have good imaging properties, then middle and high spatial frequency errors in the test system can be well calibrated. The improved imaging properties are provided by a rudimentary auxiliary optic as part of the calibration system. The auxiliary optic is simple to characterize and align to the CGH. Use of the auxiliary optic also reduces the size of the CGH required for calibration and the density of the lines required for the CGH. The resulting CGH is less expensive than the existing technology and has reduced write error and alignment error sensitivities. This CGH system is suitable for any kind of calibration using an interferometer when high spatial resolution is required. It is especially well suited for tests that include segmented optical components or large apertures.

  3. Modeling and Calibration of a Novel One-Mirror Galvanometric Laser Scanner

    Directory of Open Access Journals (Sweden)

    Chengyi Yu

    2017-01-01

    Full Text Available A laser stripe sensor has limited application when a point cloud of geometric samples on the surface of the object needs to be collected, so a galvanometric laser scanner is designed by using a one-mirror galvanometer element as its mechanical device to drive the laser stripe to sweep along the object. A novel mathematical model is derived for the proposed galvanometer laser scanner without any position assumptions and then a model-driven calibration procedure is proposed. Compared with available model-driven approaches, the influence of machining and assembly errors is considered in the proposed model. Meanwhile, a plane-constraint-based approach is proposed to extract a large number of calibration points effectively and accurately to calibrate the galvanometric laser scanner. Repeatability and accuracy of the galvanometric laser scanner are evaluated on the automobile production line to verify the efficiency and accuracy of the proposed calibration method. Experimental results show that the proposed calibration approach yields similar measurement performance compared with a look-up table calibration method.

  4. Rotary mode system initial instrument calibration

    International Nuclear Information System (INIS)

    Johns, B.R.

    1994-01-01

    The attached report contains the vendor calibration procedures used for the initial instrument calibration of the rotary core sampling equipment. The procedures are from approved vendor information files

  5. CVD calibration light systems specifications. Rev. 0

    International Nuclear Information System (INIS)

    Mcllwain, A. K.

    1992-04-01

    Two prototype Cerenkov Viewing Device Calibration Light systems for the Mark IV CVD have been fabricated. They consist of a maintenance unit that will be used by the IAEA maintenance staff and a field unit that will be used by IAEA inspectors. More detailed information on the design of the calibration units can be obtained from the document SSP-39 and additional information on the Mark IV CVD can be obtained from the operating manual published as Canadian Safeguards Support Program document CSSP 6. The specifications refer to the prototype units which will be demonstrated to the IAEA in 1992 May. Based upon the feedback from the IAEA, the instruments will be changed in the final production models to provide devices that more closely satisfy the needs of the end users

  6. Variable Acceleration Force Calibration System (VACS)

    Science.gov (United States)

    Rhew, Ray D.; Parker, Peter A.; Johnson, Thomas H.; Landman, Drew

    2014-01-01

    Conventionally, force balances have been calibrated manually, using a complex system of free hanging precision weights, bell cranks, and/or other mechanical components. Conventional methods may provide sufficient accuracy in some instances, but are often quite complex and labor-intensive, requiring three to four man-weeks to complete each full calibration. To ensure accuracy, gravity-based loading is typically utilized. However, this often causes difficulty when applying loads in three simultaneous, orthogonal axes. A complex system of levers, cranks, and cables must be used, introducing increased sources of systematic error, and significantly increasing the time and labor intensity required to complete the calibration. One aspect of the VACS is a method wherein the mass utilized for calibration is held constant, and the acceleration is changed to thereby generate relatively large forces with relatively small test masses. Multiple forces can be applied to a force balance without changing the test mass, and dynamic forces can be applied by rotation or oscillating acceleration. If rotational motion is utilized, a mass is rigidly attached to a force balance, and the mass is exposed to a rotational field. A large force can be applied by utilizing a large rotational velocity. A centrifuge or rotating table can be used to create the rotational field, and fixtures can be utilized to position the force balance. The acceleration may also be linear. For example, a table that moves linearly and accelerates in a sinusoidal manner may also be utilized. The test mass does not have to move in a path that is parallel to the ground, and no re-leveling is therefore required. Balance deflection corrections may be applied passively by monitoring the orientation of the force balance with a three-axis accelerometer package. Deflections are measured during each test run, and adjustments with respect to the true applied load can be made during the post-processing stage. This paper will

  7. Calibration of time of flight detectors using laser-driven neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Mirfayzi, S. R.; Kar, S., E-mail: s.kar@qub.ac.uk; Ahmed, H.; Green, A.; Alejo, A.; Jung, D. [Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN (United Kingdom); Krygier, A. G.; Freeman, R. R. [Department of Physics, The Ohio State University, Columbus, Ohio 43210 (United States); Clarke, R. [Central Laser Facility, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX (United Kingdom); Fuchs, J.; Vassura, L. [LULI, Ecole Polytechnique, CNRS, Route de Saclay, 91128 Palaiseau Cedex (France); Kleinschmidt, A.; Roth, M. [Institut für Kernphysik, Technische Universität Darmstadt, Schloßgartenstrasse 9, D-64289 Darmstadt,Germany (Germany); Morrison, J. T. [Propulsion Systems Directorate, Air Force Research Lab, Wright Patterson Air Force Base, Ohio 45433 (United States); Najmudin, Z.; Nakamura, H. [Blackett Laboratory, Department of Physics, Imperial College, London SW7 2AZ (United Kingdom); Norreys, P. [Central Laser Facility, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX (United Kingdom); Department of Physics, University of Oxford, Oxford OX1 3PU (United Kingdom); Oliver, M. [Department of Physics, University of Oxford, Oxford OX1 3PU (United Kingdom); Zepf, M. [Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN (United Kingdom); Helmholtz Institut Jena, D-07743 Jena (Germany); Borghesi, M. [Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University Belfast, Belfast BT7 1NN (United Kingdom); Institute of Physics of the ASCR, ELI-Beamlines Project, Na Slovance 2, 18221 Prague (Czech Republic)

    2015-07-15

    Calibration of three scintillators (EJ232Q, BC422Q, and EJ410) in a time-of-flight arrangement using a laser drive-neutron source is presented. The three plastic scintillator detectors were calibrated with gamma insensitive bubble detector spectrometers, which were absolutely calibrated over a wide range of neutron energies ranging from sub-MeV to 20 MeV. A typical set of data obtained simultaneously by the detectors is shown, measuring the neutron spectrum emitted from a petawatt laser irradiated thin foil.

  8. Calibration of time of flight detectors using laser-driven neutron source

    Science.gov (United States)

    Mirfayzi, S. R.; Kar, S.; Ahmed, H.; Krygier, A. G.; Green, A.; Alejo, A.; Clarke, R.; Freeman, R. R.; Fuchs, J.; Jung, D.; Kleinschmidt, A.; Morrison, J. T.; Najmudin, Z.; Nakamura, H.; Norreys, P.; Oliver, M.; Roth, M.; Vassura, L.; Zepf, M.; Borghesi, M.

    2015-07-01

    Calibration of three scintillators (EJ232Q, BC422Q, and EJ410) in a time-of-flight arrangement using a laser drive-neutron source is presented. The three plastic scintillator detectors were calibrated with gamma insensitive bubble detector spectrometers, which were absolutely calibrated over a wide range of neutron energies ranging from sub-MeV to 20 MeV. A typical set of data obtained simultaneously by the detectors is shown, measuring the neutron spectrum emitted from a petawatt laser irradiated thin foil.

  9. Calibration of time of flight detectors using laser-driven neutron source

    International Nuclear Information System (INIS)

    Mirfayzi, S. R.; Kar, S.; Ahmed, H.; Green, A.; Alejo, A.; Jung, D.; Krygier, A. G.; Freeman, R. R.; Clarke, R.; Fuchs, J.; Vassura, L.; Kleinschmidt, A.; Roth, M.; Morrison, J. T.; Najmudin, Z.; Nakamura, H.; Norreys, P.; Oliver, M.; Zepf, M.; Borghesi, M.

    2015-01-01

    Calibration of three scintillators (EJ232Q, BC422Q, and EJ410) in a time-of-flight arrangement using a laser drive-neutron source is presented. The three plastic scintillator detectors were calibrated with gamma insensitive bubble detector spectrometers, which were absolutely calibrated over a wide range of neutron energies ranging from sub-MeV to 20 MeV. A typical set of data obtained simultaneously by the detectors is shown, measuring the neutron spectrum emitted from a petawatt laser irradiated thin foil

  10. Laser surveillance system (LASSY)

    International Nuclear Information System (INIS)

    Boeck, H.; Hammer, J.

    1988-01-01

    The development progress during the reporting period 1988 of the laser surveillance system of spent fuel pools is summarized. The present engineered system comes close to a final version for field application as all technical questions have been solved in 1988. 14 figs., 1 tab. (Author)

  11. Autonomous Kinematic Calibration of the Robot Manipulator with a Linear Laser-Vision Sensor

    Science.gov (United States)

    Kang, Hee-Jun; Jeong, Jeong-Woo; Shin, Sung-Weon; Suh, Young-Soo; Ro, Young-Schick

    This paper presents a new autonomous kinematic calibration technique by using a laser-vision sensor called "Perceptron TriCam Contour". Because the sensor measures by capturing the image of a projected laser line on the surface of the object, we set up a long, straight line of a very fine string inside the robot workspace, and then allow the sensor mounted on a robot to measure the point intersection of the line of string and the projected laser line. The data collected by changing robot configuration and measuring the intersection points are constrained to on a single straght line such that the closed-loop calibration method can be applied. The obtained calibration method is simple and accurate and also suitable for on-site calibration in an industrial environment. The method is implemented using Hyundai VORG-35 for its effectiveness.

  12. Aurora laser optical system

    International Nuclear Information System (INIS)

    Hanlon, J.A.; McLeod, J.

    1987-01-01

    Aurora is the Los Alamos short-pulse high-power krypton fluoride laser system. It is primarily an end-to-end technology demonstration prototype for large-scale UV laser systems of interest for short-wavelength inertial confinement fusion (ICF) investigations. The system is designed to employ optical angular multiplexing and aerial amplification by electron-beam-driven KrF laser amplifiers to deliver to ICF targets a stack of pulses with a duration of 5 ns containing several kilojoules at a wavelength of 248 nm. A program of high-energy density plasma physics investigations is now planned, and a sophisticated target chamber was constructed. The authors describe the design of the optical system for Aurora and report its status. This optical system was designed and is being constructed in two phases. The first phase carries only through the amplifier train and does not include a target chamber or any demultiplexing. Installation should be complete, and some performance results should be available. The second phase provides demultiplexing and carries the laser light to target. The complete design is reported

  13. Laser surveillance system (LASSY)

    International Nuclear Information System (INIS)

    Boeck, H.

    1991-09-01

    Laser Surveillance System (LASSY) is a beam of laser light which scans a plane above the water or under-water in a spent-fuel pond. The system can detect different objects and estimates its coordinates and distance as well. LASSY can operate in stand-alone configuration or in combination with a video surveillance to trigger signal to a videorecorder. The recorded information on LASSY computer's disk comprises date, time, start and stop angle of detected alarm, the size of the disturbance indicated in number of deviated points and some other information. The information given by the laser system cannot be fully substituted by TV camera pictures since the scanning beam creates a horizontal surveillance plan. The engineered prototype laser system long-term field test has been carried out in Soluggia (Italy) and has shown its feasibility and reliability under the conditions of real spent fuel storage pond. The verification of the alarm table on the LASSY computer with the recorded video pictures of TV surveillance system confirmed that all alarm situations have been detected. 5 refs

  14. Calibration

    International Nuclear Information System (INIS)

    Greacen, E.L.; Correll, R.L.; Cunningham, R.B.; Johns, G.G.; Nicolls, K.D.

    1981-01-01

    Procedures common to different methods of calibration of neutron moisture meters are outlined and laboratory and field calibration methods compared. Gross errors which arise from faulty calibration techniques are described. The count rate can be affected by the dry bulk density of the soil, the volumetric content of constitutional hydrogen and other chemical components of the soil and soil solution. Calibration is further complicated by the fact that the neutron meter responds more strongly to the soil properties close to the detector and source. The differences in slope of calibration curves for different soils can be as much as 40%

  15. Coherent laser vision system

    International Nuclear Information System (INIS)

    Sebastion, R.L.

    1995-01-01

    The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system

  16. Coherent laser vision system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastion, R.L. [Coleman Research Corp., Springfield, VA (United States)

    1995-10-01

    The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system.

  17. Laser's calibration of an AOTF-based spectral colorimeter

    Science.gov (United States)

    Emelianov, Sergey P.; Khrustalev, Vladimir N.; Kochin, Leonid B.; Polosin, Lev L.

    2003-06-01

    The paper is devoted to expedients of AOTF spectral colorimeters calibration. The spectrometer method of color values measuring with reference to spectral colorimeters on AOTF surveyed. The theoretical exposition of spectrometer data processing expedients is offered. The justified source of radiation choice, suitable for calibration of spectral colorimeters is carried out. The experimental results for different acousto-optical mediums and modes of interaction are submitted.

  18. Traveling wave laser system

    International Nuclear Information System (INIS)

    Gregg, D.W.; Kidder, R.E.; Biehl, A.T.

    1975-01-01

    The invention broadly involves a method and means for generating a traveling wave laser pulse and is basically analogous to a single pass light amplifier system. However, the invention provides a traveling wave laser pulse of almost unlimited energy content, wherein a gain medium is pumped in a traveling wave mode, the traveling wave moving at essentially the velocity of light to generate an amplifying region or zone which moves through the medium at the velocity of light in the presence of directed stimulating radiation, thereby generating a traveling coherent, directed radiation pulse moving with the amplification zone through the gain medium. (U.S.)

  19. System for Automated Calibration of Vector Modulators

    Science.gov (United States)

    Lux, James; Boas, Amy; Li, Samuel

    2009-01-01

    Vector modulators are used to impose baseband modulation on RF signals, but non-ideal behavior limits the overall performance. The non-ideal behavior of the vector modulator is compensated using data collected with the use of an automated test system driven by a LabVIEW program that systematically applies thousands of control-signal values to the device under test and collects RF measurement data. The technology innovation automates several steps in the process. First, an automated test system, using computer controlled digital-to-analog converters (DACs) and a computer-controlled vector network analyzer (VNA) systematically can apply different I and Q signals (which represent the complex number by which the RF signal is multiplied) to the vector modulator under test (VMUT), while measuring the RF performance specifically, gain and phase. The automated test system uses the LabVIEW software to control the test equipment, collect the data, and write it to a file. The input to the Lab - VIEW program is either user-input for systematic variation, or is provided in a file containing specific test values that should be fed to the VMUT. The output file contains both the control signals and the measured data. The second step is to post-process the file to determine the correction functions as needed. The result of the entire process is a tabular representation, which allows translation of a desired I/Q value to the required analog control signals to produce a particular RF behavior. In some applications, corrected performance is needed only for a limited range. If the vector modulator is being used as a phase shifter, there is only a need to correct I and Q values that represent points on a circle, not the entire plane. This innovation has been used to calibrate 2-GHz MMIC (monolithic microwave integrated circuit) vector modulators in the High EIRP Cluster Array project (EIRP is high effective isotropic radiated power). These calibrations were then used to create

  20. 3D camera assisted fully automated calibration of scanning laser Doppler vibrometers

    International Nuclear Information System (INIS)

    Sels, Seppe; Ribbens, Bart; Mertens, Luc; Vanlanduit, Steve

    2016-01-01

    Scanning laser Doppler vibrometers (LDV) are used to measure full-field vibration shapes of products and structures. In most commercially available scanning laser Doppler vibrometer systems the user manually draws a grid of measurement locations on a 2D camera image of the product. The determination of the correct physical measurement locations can be a time consuming and diffcult task. In this paper we present a new methodology for product testing and quality control that integrates 3D imaging techniques with vibration measurements. This procedure allows to test prototypes in a shorter period because physical measurements locations will be located automatically. The proposed methodology uses a 3D time-of-flight camera to measure the location and orientation of the test-object. The 3D image of the time-of-flight camera is then matched with the 3D-CAD model of the object in which measurement locations are pre-defined. A time of flight camera operates strictly in the near infrared spectrum. To improve the signal to noise ratio in the time-of-flight measurement, a time-of-flight camera uses a band filter. As a result of this filter, the laser spot of most laser vibrometers is invisible in the time-of-flight image. Therefore a 2D RGB-camera is used to find the laser-spot of the vibrometer. The laser spot is matched to the 3D image obtained by the time-of-flight camera. Next an automatic calibration procedure is used to aim the laser at the (pre)defined locations. Another benefit from this methodology is that it incorporates automatic mapping between a CAD model and the vibration measurements. This mapping can be used to visualize measurements directly on a 3D CAD model. Secondly the orientation of the CAD model is known with respect to the laser beam. This information can be used to find the direction of the measured vibration relatively to the surface of the object. With this direction, the vibration measurements can be compared more precisely with numerical

  1. 3D camera assisted fully automated calibration of scanning laser Doppler vibrometers

    Energy Technology Data Exchange (ETDEWEB)

    Sels, Seppe, E-mail: Seppe.Sels@uantwerpen.be; Ribbens, Bart; Mertens, Luc; Vanlanduit, Steve [Op3Mech Research Group, University of Antwerp, Salesianenlaan 90, 2660 Antwerp (Belgium)

    2016-06-28

    Scanning laser Doppler vibrometers (LDV) are used to measure full-field vibration shapes of products and structures. In most commercially available scanning laser Doppler vibrometer systems the user manually draws a grid of measurement locations on a 2D camera image of the product. The determination of the correct physical measurement locations can be a time consuming and diffcult task. In this paper we present a new methodology for product testing and quality control that integrates 3D imaging techniques with vibration measurements. This procedure allows to test prototypes in a shorter period because physical measurements locations will be located automatically. The proposed methodology uses a 3D time-of-flight camera to measure the location and orientation of the test-object. The 3D image of the time-of-flight camera is then matched with the 3D-CAD model of the object in which measurement locations are pre-defined. A time of flight camera operates strictly in the near infrared spectrum. To improve the signal to noise ratio in the time-of-flight measurement, a time-of-flight camera uses a band filter. As a result of this filter, the laser spot of most laser vibrometers is invisible in the time-of-flight image. Therefore a 2D RGB-camera is used to find the laser-spot of the vibrometer. The laser spot is matched to the 3D image obtained by the time-of-flight camera. Next an automatic calibration procedure is used to aim the laser at the (pre)defined locations. Another benefit from this methodology is that it incorporates automatic mapping between a CAD model and the vibration measurements. This mapping can be used to visualize measurements directly on a 3D CAD model. Secondly the orientation of the CAD model is known with respect to the laser beam. This information can be used to find the direction of the measured vibration relatively to the surface of the object. With this direction, the vibration measurements can be compared more precisely with numerical

  2. Standardization of Laser Methods and Techniques for Vibration Measurements and Calibrations

    International Nuclear Information System (INIS)

    Martens, Hans-Juergen von

    2010-01-01

    The realization and dissemination of the SI units of motion quantities (vibration and shock) have been based on laser interferometer methods specified in international documentary standards. New and refined laser methods and techniques developed by national metrology institutes and by leading manufacturers in the past two decades have been swiftly specified as standard methods for inclusion into in the series ISO 16063 of international documentary standards. A survey of ISO Standards for the calibration of vibration and shock transducers demonstrates the extended ranges and improved accuracy (measurement uncertainty) of laser methods and techniques for vibration and shock measurements and calibrations. The first standard for the calibration of laser vibrometers by laser interferometry or by a reference accelerometer calibrated by laser interferometry (ISO 16063-41) is on the stage of a Draft International Standard (DIS) and may be issued by the end of 2010. The standard methods with refined techniques proved to achieve wider measurement ranges and smaller measurement uncertainties than that specified in the ISO Standards. The applicability of different standardized interferometer methods to vibrations at high frequencies was recently demonstrated up to 347 kHz (acceleration amplitudes up to 350 km/s 2 ). The relative deviations between the amplitude measurement results of the different interferometer methods that were applied simultaneously, differed by less than 1% in all cases.

  3. Calibration method of radiation monitoring system at TQNPC

    International Nuclear Information System (INIS)

    Liu Zhengshan; Zhang Qingli; Liu Jinjin; Miao Yuxing; Geng Lixin; Zhuang Yun; Dong Jianfeng; He Change

    2009-04-01

    The calibration methods and calibration device for standard monitor of radioactive particulate, iodine, noble gas and so on are not yet set up at home. On consideration of the present situation of the radiation monitoring system at the Third Qinshan Nuclear Power Co. Ltd., we have studied the calibration method of these radiation monitoring instruments used for measuring the waste liquid, particulate, iodine and noble gas produced during the operation of nuclear reactor. Through the check against these instruments during the No. 202 and No. 103 overhaul, we got initially the method of the calibration and obtained the transfer coefficient of calibration when secondary solid sources are used for calibration. Through the testing and calibration, the credibility of the radiation monitoring system is enhanced. And at the same time, the problems existing in the calibration are discussed. (authors)

  4. Absolutely calibrated, time-resolved measurements of soft x rays using transmission grating spectrometers at the Nike Laser Facility

    International Nuclear Information System (INIS)

    Weaver, J.L.; Feldman, U.; Seely, J.F.; Holland, G.; Serlin, V.; Klapisch, M.; Columbant, D.; Mostovych, A.

    2001-01-01

    Accurate simulation of pellet implosions for direct drive inertial confinement fusion requires benchmarking the codes with experimental data. The Naval Research Laboratory (NRL) has begun to measure the absolute intensity of radiation from laser irradiated targets to provide critical information for the radiatively preheated pellet designs developed by the Nike laser group. Two main diagnostics for this effort are two spectrometers incorporating three detection systems. While both spectrometers use 2500 lines/mm transmission gratings, one instrument is coupled to a soft x-ray streak camera and the other is coupled to both an absolutely calibrated Si photodiode array and a charge coupled device (CCD) camera. Absolute calibration of spectrometer components has been undertaken at the National Synchrotron Light Source at Brookhaven National Laboratories. Currently, the system has been used to measure the spatially integrated soft x-ray flux as a function of target material, laser power, and laser spot size. A comparison between measured and calculated flux for Au and CH targets shows reasonable agreement to one-dimensional modeling for two laser power densities

  5. Fusion neutron detector calibration using a table-top laser generated plasma neutron source

    International Nuclear Information System (INIS)

    Hartke, R.; Symes, D.R.; Buersgens, F.; Ruggles, L.E.; Porter, J.L.; Ditmire, T.

    2005-01-01

    Using a high intensity, femtosecond laser driven neutron source, a high-sensitivity neutron detector was calibrated. This detector is designed for observing fusion neutrons at the Z accelerator in Sandia National Laboratories. Nuclear fusion from laser driven deuterium cluster explosions was used to generate a clean source of nearly monoenergetic 2.45 MeV neutrons at a well-defined time. This source can run at 10 Hz and was used to build up a clean pulse-height spectrum on scintillating neutron detectors giving a very accurate calibration for neutron yields at 2.45 MeV

  6. PEP Laser Surveying System

    International Nuclear Information System (INIS)

    Lauritzen, T.; Sah, R.C.

    1979-03-01

    A Laser Surveying System has been developed to survey the beam elements of the PEP storage ring. This system provides automatic data acquisition and analysis in order to increase survey speed and to minimize operator error. Two special instruments, the Automatic Readout Micrometer and the Small Automatic Micrometer, have been built for measuring the locations of fiducial points on beam elements with respect to the light beam from a laser. These instruments automatically encode offset distances and read them into the memory of an on-line computer. Distances along the beam line are automatically encoded with a third instrument, the Automatic Readout Tape Unit. When measurements of several beam elements have been taken, the on-line computer analyzes the measured data, compared them with desired parameters, and calculates the required adjustments to beam element support stands

  7. Optically pumped laser systems

    International Nuclear Information System (INIS)

    DeMaria, A.J.; Mack, M.E.

    1975-01-01

    Laser systems which are pumped by an electric discharge formed in a gas are disclosed. The discharge is in the form of a vortex stabilized electric arc which is triggered with an auxiliary energy source. At high enough repetition rates residual ionization between successive pulses contributes to the pulse stabilization. The arc and the gain medium are positioned inside an optical pumping cavity where light from the arc is coupled directly into the gain medium

  8. Optical power calibrator based on a stabilized green He-Ne laser and a cryogenic absolute radiometer

    International Nuclear Information System (INIS)

    Varpula, T.; Seppa, H.; Saari, J.M.

    1989-01-01

    This paper describes an optical power calibrator whose overall calibration uncertainty is less than 10 -4 for an optical power of 0.13 mW. The laser light source of the system operates at a wavelength of 543.5 nm, being close to the wavelength at which the candela is defined, 555 nm. A stable optical power is achieved by stabilizing the intensity and the frequency of a green He-Ne laser. The optical power is detected by a cryogenic absolute radiometer based on the principle of electrical substitution radiometry. It can be employed to measure optical power up to 0.5 mW in the visible and near infrared region

  9. Calibration-free absolute frequency response measurement of directly modulated lasers based on additional modulation.

    Science.gov (United States)

    Zhang, Shangjian; Zou, Xinhai; Wang, Heng; Zhang, Yali; Lu, Rongguo; Liu, Yong

    2015-10-15

    A calibration-free electrical method is proposed for measuring the absolute frequency response of directly modulated semiconductor lasers based on additional modulation. The method achieves the electrical domain measurement of the modulation index of directly modulated lasers without the need for correcting the responsivity fluctuation in the photodetection. Moreover, it doubles measuring frequency range by setting a specific frequency relationship between the direct and additional modulation. Both the absolute and relative frequency response of semiconductor lasers are experimentally measured from the electrical spectrum of the twice-modulated optical signal, and the measured results are compared to those obtained with conventional methods to check the consistency. The proposed method provides calibration-free and accurate measurement for high-speed semiconductor lasers with high-resolution electrical spectrum analysis.

  10. Laser optogalvanic wavelength calibration with a commercial hollow cathode iron - neon discharge lamp

    Science.gov (United States)

    Zhu, Xinming; Nur, Abdullahi H.; Misra, Prabhakar

    1994-01-01

    351 optogalvanic transitions have been observed in the 337 - 598 nm wavelength region using an iron - neon hollow cathode discharge lamp and a pulsed tunable dye laser. 223 of these have been identified as transitions associated with neon energy levels. These optogalvanic transitions have allowed, in conjunction with interference fringes recorded concomitantly with an etalon, the calibration of the dye laser wavelength with 0.3/cm accuracy.

  11. Precise calibration of few-cycle laser pulses with atomic hydrogen

    Science.gov (United States)

    Wallace, W. C.; Kielpinski, D.; Litvinyuk, I. V.; Sang, R. T.

    2017-12-01

    Interaction of atoms and molecules with strong electric fields is a fundamental process in many fields of research, particularly in the emerging field of attosecond science. Therefore, understanding the physics underpinning those interactions is of significant interest to the scientific community. One crucial step in this understanding is accurate knowledge of the few-cycle laser field driving the process. Atomic hydrogen (H), the simplest of all atomic species, plays a key role in benchmarking strong-field processes. Its wide-spread use as a testbed for theoretical calculations allows the comparison of approximate theoretical models against nearly-perfect numerical solutions of the three-dimensional time-dependent Schrödinger equation. Until recently, relatively little experimental data in atomic H was available for comparison to these models, and was due mostly due to the difficulty in the construction and use of atomic H sources. Here, we review our most recent experimental results from atomic H interaction with few-cycle laser pulses and how they have been used to calibrate important laser pulse parameters such as peak intensity and the carrier-envelope phase (CEP). Quantitative agreement between experimental data and theoretical predictions for atomic H has been obtained at the 10% uncertainty level, allowing for accurate laser calibration intensity at the 1% level. Using this calibration in atomic H, both accurate CEP data and an intensity calibration standard have been obtained Ar, Kr, and Xe; such gases are in common use for strong-field experiments. This calibration standard can be used by any laboratory using few-cycle pulses in the 1014 W cm-2 intensity regime centered at 800 nm wavelength to accurately calibrate their peak laser intensity to within few-percent precision.

  12. Improvement in QEPAS system utilizing a second harmonic based wavelength calibration technique

    Science.gov (United States)

    Zhang, Qinduan; Chang, Jun; Wang, Fupeng; Wang, Zongliang; Xie, Yulei; Gong, Weihua

    2018-05-01

    A simple laser wavelength calibration technique, based on second harmonic signal, is demonstrated in this paper to improve the performance of quartz enhanced photoacoustic spectroscopy (QEPAS) gas sensing system, e.g. improving the signal to noise ratio (SNR), detection limit and long-term stability. Constant current, corresponding to the gas absorption line, combining f/2 frequency sinusoidal signal are used to drive the laser (constant driving mode), a software based real-time wavelength calibration technique is developed to eliminate the wavelength drift due to ambient fluctuations. Compared to conventional wavelength modulation spectroscopy (WMS), this method allows lower filtering bandwidth and averaging algorithm applied to QEPAS system, improving SNR and detection limit. In addition, the real-time wavelength calibration technique guarantees the laser output is modulated steadily at gas absorption line. Water vapor is chosen as an objective gas to evaluate its performance compared to constant driving mode and conventional WMS system. The water vapor sensor was designed insensitive to the incoherent external acoustic noise by the numerical averaging technique. As a result, the SNR increases 12.87 times in wavelength calibration technique based system compared to conventional WMS system. The new system achieved a better linear response (R2 = 0 . 9995) in concentration range from 300 to 2000 ppmv, and achieved a minimum detection limit (MDL) of 630 ppbv.

  13. Systematic calibration of an integrated x-ray and optical tomography system for preclinical radiation research

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yidong, E-mail: yidongyang@med.miami.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 and Department of Radiation Oncology, University of Miami School of Medicine, Miami, Florida 33136 (United States); Wang, Ken Kang-Hsin; Wong, John W. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 (United States); Eslami, Sohrab; Iordachita, Iulian I. [Laboratory for Computational Sensing and Robotics, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Patterson, Michael S. [Juravinski Cancer Centre and Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S4K1 (Canada)

    2015-04-15

    Purpose: The cone beam computed tomography (CBCT) guided small animal radiation research platform (SARRP) has been developed for focal tumor irradiation, allowing laboratory researchers to test basic biological hypotheses that can modify radiotherapy outcomes in ways that were not feasible previously. CBCT provides excellent bone to soft tissue contrast, but is incapable of differentiating tumors from surrounding soft tissue. Bioluminescence tomography (BLT), in contrast, allows direct visualization of even subpalpable tumors and quantitative evaluation of tumor response. Integration of BLT with CBCT offers complementary image information, with CBCT delineating anatomic structures and BLT differentiating luminescent tumors. This study is to develop a systematic method to calibrate an integrated CBCT and BLT imaging system which can be adopted onboard the SARRP to guide focal tumor irradiation. Methods: The integrated imaging system consists of CBCT, diffuse optical tomography (DOT), and BLT. The anatomy acquired from CBCT and optical properties acquired from DOT serve as a priori information for the subsequent BLT reconstruction. Phantoms were designed and procedures were developed to calibrate the CBCT, DOT/BLT, and the entire integrated system. Geometrical calibration was performed to calibrate the CBCT system. Flat field correction was performed to correct the nonuniform response of the optical imaging system. Absolute emittance calibration was performed to convert the camera readout to the emittance at the phantom or animal surface, which enabled the direct reconstruction of the bioluminescence source strength. Phantom and mouse imaging were performed to validate the calibration. Results: All calibration procedures were successfully performed. Both CBCT of a thin wire and a euthanized mouse revealed no spatial artifact, validating the accuracy of the CBCT calibration. The absolute emittance calibration was validated with a 650 nm laser source, resulting in a 3

  14. Systematic calibration of an integrated x-ray and optical tomography system for preclinical radiation research

    International Nuclear Information System (INIS)

    Yang, Yidong; Wang, Ken Kang-Hsin; Wong, John W.; Eslami, Sohrab; Iordachita, Iulian I.; Patterson, Michael S.

    2015-01-01

    Purpose: The cone beam computed tomography (CBCT) guided small animal radiation research platform (SARRP) has been developed for focal tumor irradiation, allowing laboratory researchers to test basic biological hypotheses that can modify radiotherapy outcomes in ways that were not feasible previously. CBCT provides excellent bone to soft tissue contrast, but is incapable of differentiating tumors from surrounding soft tissue. Bioluminescence tomography (BLT), in contrast, allows direct visualization of even subpalpable tumors and quantitative evaluation of tumor response. Integration of BLT with CBCT offers complementary image information, with CBCT delineating anatomic structures and BLT differentiating luminescent tumors. This study is to develop a systematic method to calibrate an integrated CBCT and BLT imaging system which can be adopted onboard the SARRP to guide focal tumor irradiation. Methods: The integrated imaging system consists of CBCT, diffuse optical tomography (DOT), and BLT. The anatomy acquired from CBCT and optical properties acquired from DOT serve as a priori information for the subsequent BLT reconstruction. Phantoms were designed and procedures were developed to calibrate the CBCT, DOT/BLT, and the entire integrated system. Geometrical calibration was performed to calibrate the CBCT system. Flat field correction was performed to correct the nonuniform response of the optical imaging system. Absolute emittance calibration was performed to convert the camera readout to the emittance at the phantom or animal surface, which enabled the direct reconstruction of the bioluminescence source strength. Phantom and mouse imaging were performed to validate the calibration. Results: All calibration procedures were successfully performed. Both CBCT of a thin wire and a euthanized mouse revealed no spatial artifact, validating the accuracy of the CBCT calibration. The absolute emittance calibration was validated with a 650 nm laser source, resulting in a 3

  15. Application of Various Lasers to Laser Trimming Resistance System

    Institute of Scientific and Technical Information of China (English)

    SUN Ji-feng

    2007-01-01

    Though the laser trimming resistance has been an old laser machining industry for over 30 years, the development of technology brings new alternative lasers which can be used for the traditional machining. The paper describes application of various lasers to laser trimming resistance system including early traditional krypton arc lamp pumped Nd:YAG to laser, modern popular diode pumped solid state laser and the present advanced harmonic diode pumped solid state laser. Using the new alternative lasers in the laser trimming resistance system can dramatically improve the yields and equipment performance.

  16. Calibration of matrix-assisted laser desorption/ionization time-of-flight peptide mass fingerprinting spectra

    DEFF Research Database (Denmark)

    Hjernø, Karin; Højrup, Peter

    2007-01-01

    This chapter describes a number of aspects important for calibration of matrix-assisted laser desorption/ionization time-of-flight spectra prior to peptide mass fingerprinting searches. Both multipoint internal calibration and mass defect-based calibration is illustrated. The chapter describes ho...

  17. Research on a high-precision calibration method for tunable lasers

    Science.gov (United States)

    Xiang, Na; Li, Zhengying; Gui, Xin; Wang, Fan; Hou, Yarong; Wang, Honghai

    2018-03-01

    Tunable lasers are widely used in the field of optical fiber sensing, but nonlinear tuning exists even for zero external disturbance and limits the accuracy of the demodulation. In this paper, a high-precision calibration method for tunable lasers is proposed. A comb filter is introduced and the real-time output wavelength and scanning rate of the laser are calibrated by linear fitting several time-frequency reference points obtained from it, while the beat signal generated by the auxiliary interferometer is interpolated and frequency multiplied to find more accurate zero crossing points, with these points being used as wavelength counters to resample the comb signal to correct the nonlinear effect, which ensures that the time-frequency reference points of the comb filter are linear. A stability experiment and a strain sensing experiment verify the calibration precision of this method. The experimental result shows that the stability and wavelength resolution of the FBG demodulation can reach 0.088 pm and 0.030 pm, respectively, using a tunable laser calibrated by the proposed method. We have also compared the demodulation accuracy in the presence or absence of the comb filter, with the result showing that the introduction of the comb filter results to a 15-fold wavelength resolution enhancement.

  18. Laser system using ultra-short laser pulses

    Science.gov (United States)

    Dantus, Marcos [Okemos, MI; Lozovoy, Vadim V [Okemos, MI; Comstock, Matthew [Milford, MI

    2009-10-27

    A laser system using ultrashort laser pulses is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal.

  19. CYLINDER-BASED SELF-CALIBRATION OF A PANORAMIC TERRESTRIAL LASER SCANNER

    Directory of Open Access Journals (Sweden)

    T. O. Chan

    2012-07-01

    Full Text Available Terrestrial Laser Scanners (TLSs have become state-of-the-art metrological sensors for many surveying purposes in recent years. Due to the demand for high precision surveying with TLSs, efficient, rigorous and in-situ calibration methodologies are always desired. Recent research on in-situ calibration with planar features has demonstrated improved cost-effectiveness and promising results (Glennie and Lichti, 2010; Chow et al., 2011; Chow et al., 2012. However, if there is a need for calibrating the scanners when sufficient plane surfaces with several orientations are not available, as commonly occurs indoors, other common geometric features, namely cylindrical structures, can be used as alternative geometric constraints for in-situ self-calibration. Cylindrical features can be found in indoor environments such as water pipes attached to the walls or suspended from ceilings, concrete pillars, metal poles and many others. In this paper, three 3D models of cylinders, with vertical and horizontal orientations containing one scaling, two rotational and two translational parameters are discussed. The cylinder models are parameterized with the sexternal orientation parameters and the additional parameters as the least-squares functional models for the self-calibration. The selfcalibration is examined with the real data obtained from the Lecia HDS6100 panoramic TLS. The results of vertical, horizontal and mixed cylinder-based calibration with data captured by different scanner position are analysed in detail in terms of the parameters correlations. The results show realistic estimation of calibration parameters for several cases. The results also suggest that using both vertical and horizontal cylinders for the calibration can effectively decorrelate the parameters especially for the case of lack of cylinder point cloud overlap. The concepts developed in this paper might also be extended to the hybrid type TLSs, as well as to the self-calibration of

  20. Beam-based calibration system of BPM offset on BEPC

    International Nuclear Information System (INIS)

    Hu Chunliang

    2004-01-01

    The ever-increasing demand for better performance from circular accelerators requires improved methods to calibrate beam position monitors (BPM). A beam based calibration system has been established to locate the centers of the BPM with respect to the magnetic center of quadrupole magnets. Additional windings are applied to the quadrupole magnets to make the quadrupole magnetic strength individually adjustable and the number of the power supply of all 32 additional windings is only one. Software system has been finished to automatically measure the offsets of BPMs. The effect of the beam-based calibration system shows that the calibration of BPM has been more quickly and accurately

  1. Calibration of sources for alpha spectroscopy systems

    International Nuclear Information System (INIS)

    Freitas, I.S.M.; Goncalez, O.L.

    1992-01-01

    This paper describes the calibration methodology for measuring the total alpha activity of plane and thin sources with the Alpha Spectrometer for Silicon Detector in the Nuclear Measures and Dosimetry laboratory at IEAv/CTA. (author)

  2. Automatic multi-camera calibration for deployable positioning systems

    Science.gov (United States)

    Axelsson, Maria; Karlsson, Mikael; Rudner, Staffan

    2012-06-01

    Surveillance with automated positioning and tracking of subjects and vehicles in 3D is desired in many defence and security applications. Camera systems with stereo or multiple cameras are often used for 3D positioning. In such systems, accurate camera calibration is needed to obtain a reliable 3D position estimate. There is also a need for automated camera calibration to facilitate fast deployment of semi-mobile multi-camera 3D positioning systems. In this paper we investigate a method for automatic calibration of the extrinsic camera parameters (relative camera pose and orientation) of a multi-camera positioning system. It is based on estimation of the essential matrix between each camera pair using the 5-point method for intrinsically calibrated cameras. The method is compared to a manual calibration method using real HD video data from a field trial with a multicamera positioning system. The method is also evaluated on simulated data from a stereo camera model. The results show that the reprojection error of the automated camera calibration method is close to or smaller than the error for the manual calibration method and that the automated calibration method can replace the manual calibration.

  3. Development of a calibration system for surface contamination monitors

    International Nuclear Information System (INIS)

    Marechal, M.H.H.; Barbosa, M.P.

    1992-01-01

    A calibration system for surface contamination monitors is developed, aiming supply the existence demand of these instruments. A experimental arrangement and a methodology are described. The advantages of use this system for calibration routine optimization are also discussed. (C.G.C.)

  4. Laser engineering of microbial systems

    Science.gov (United States)

    Yusupov, V. I.; Gorlenko, M. V.; Cheptsov, V. S.; Minaev, N. V.; Churbanova, E. S.; Zhigarkov, V. S.; Chutko, E. A.; Evlashin, S. A.; Chichkov, B. N.; Bagratashvili, V. N.

    2018-06-01

    A technology of laser engineering of microbial systems (LEMS) based on the method of laser-induced transfer of heterogeneous mixtures containing microorganisms (laser bioprinting) is described. This technology involves laser printing of soil microparticles by focusing near-infrared laser pulses on a specially prepared gel/soil mixture spread onto a gold-coated glass plate. The optimal range of laser energies from the point of view of the formation of stable jets and droplets with minimal negative impact on living systems of giant accelerations, laser pulse irradiation, and Au nanoparticles was found. Microsamples of soil were printed on glucose-peptone-yeast agar plates to estimate the LEMS process influence on structural and morphological microbial diversity. The obtained results were compared with traditionally treated soil samples. It was shown that LEMS technology allows significantly increasing the biodiversity of printed organisms and is effective for isolating rare or unculturable microorganisms.

  5. A flexible calibration method for laser displacement sensors based on a stereo-target

    International Nuclear Information System (INIS)

    Zhang, Jie; Sun, Junhua; Liu, Zhen; Zhang, Guangjun

    2014-01-01

    Laser displacement sensors (LDSs) are widely used in online measurement owing to their characteristics of non-contact, high measurement speed, etc. However, existing calibration methods for LDSs based on the traditional triangulation measurement model are time-consuming and tedious to operate. In this paper, a calibration method for LDSs based on a vision measurement model of the LDS is presented. According to the constraint relationships of the model parameters, the calibration is implemented by freely moving a stereo-target at least twice in the field of view of the LDS. Both simulation analyses and real experiments were conducted. Experimental results demonstrate that the calibration method achieves an accuracy of 0.044 mm within the measurement range of about 150 mm. Compared to traditional calibration methods, the proposed method has no special limitation on the relative position of the LDS and the target. The linearity approximation of the measurement model in the calibration is not needed, and thus the measurement range is not limited in the linearity range. It is easy and quick to implement the calibration for the LDS. The method can be applied in wider fields. (paper)

  6. Calibration of the ISOLDE acceleration voltage using a high-precision voltage divider and applying collinear fast beam laser spectroscopy

    CERN Document Server

    Krieger, A.; Catherall, R.; Hochschulz, F.; Kramer, J.; Neugart, R.; Rosendahl, S.; Schipper, J.; Siesling, E.; Weinheimer, Ch.; Yordanov, D.T.; Nortershauser, W.

    2011-01-01

    A high-voltage divider with accuracy at the ppm level and collinear laser spectroscopy were used to calibrate the highvoltage installation at the radioactive ion beam facility ISOLDE at CERN. The accurate knowledge of this voltage is particularly important for collinear laser spectroscopy measurements. Beam velocity measurements using frequencycomb based collinear laser spectroscopy agree with the new calibration. Applying this, one obtains consistent results for isotope shifts of stable magnesium isotopes measured using collinear spectroscopy and laser spectroscopy on laser-cooled ions in a trap. The long-term stability and the transient behavior during recovery from a voltage dropout were investigated for the different power supplies currently applied at ISOLDE.

  7. Calibration curves for commercial copper and aluminum alloys using handheld laser-induced breakdown spectroscopy

    Science.gov (United States)

    Bennett, B. N.; Martin, M. Z.; Leonard, D. N.; Garlea, E.

    2018-03-01

    Handheld laser-induced breakdown spectroscopy (HH LIBS) was used to study the elemental composition of four copper alloys and four aluminum alloys to produce calibration curves. The HH LIBS instrument used is a SciAps Z-500, commercially available, that contains a class-1 solid-state laser with an output wavelength of 1532 nm, laser energy of 5 mJ/pulse, and a pulse duration of 5 ns. Test samples were solid specimens comprising copper and aluminum alloys and data were collected from the samples' surface at three different locations, employing a 12-point-grid pattern for each data set. All three data sets of the spectra were averaged, and the intensity, corrected by subtraction of background, was used to produce the elemental calibration curves. Calibration curves are presented for the matrix elements, copper and aluminum, as well as several minor elements. The surface damage produced by the laser was examined by microscopy. The alloys were tested in air and in a glovebox to evaluate the instrument's ability to identify the constituents within materials under different environmental conditions. The main objective of using this HH LIBS technology is to determine its capability to fingerprint the presence of certain elements related to subpercent level within materials in real time and in situ, as a starting point for undertaking future complex material characterization work.

  8. System for calibration of SPEAR transport line toroids

    International Nuclear Information System (INIS)

    Huang, T.V.; Smith, H.; Crook, K.

    1977-01-01

    A one nanosecond pulse generator was developed for calibration of the intensity monitors (toroids) in the SPEAR transport lines. The generator, located at the toroid, is simple, low cost and resistant to radiation. The generator and its connection to the standard SLAC toroid calibration system are described

  9. A diffraction limited nitrogen laser for detector calibration in high energy physics

    International Nuclear Information System (INIS)

    Hartjes, F.G.

    1990-01-01

    This thesis consists of two parts. In part I the operation of a pulsed two-stage nitrogen laser is described. In contrast to most other lasers an optical resonator can not be used in a nitrogen laser because of the very short pulse time (∼ 1 ns). Therefore the emitted beam of a simple nitrogen laser has a large divergence. A nitrogen laser with a small beam divergence however can be constructed via the 'Master Oscillator Power Amplifier' principle. Herein a double nitrogen laser system is employed in which both lasers fire simultaneously. The diameter of the laser beam from the first stage (oscillator) is enlarged by a telescope by which the divergence decreases strongly. In a second stage (amplifier) subsequently the weak laser beam is amplified again. The outcoming beam has an elongated diameter which is changed in an approximately round form by a telescope of two cylindrical lenses. The process leading to the formation of population inversion in the nitrogen causing emission of laser ligth is described. The electric circuit, which delivers the high-voltage pulse causing the electric discharge in the laser cavity, is described. The mechanical construction of the laser, in particular with regard to the choices of the materials, is described. Finally, the optical system of the two-stage nitrogen laser is explained. In part II the application of the two-stage nitrogen laser in high-energy physics is treated. Instructions are given about the practical use of the laser: the usual optical system and the ionization profile to be expected in the detector gas. Herein three different kinds of beams are distinguished: the parallel beam, the weakly focussed, and the strongly focussed beam. Some examples are given of the use of the laser: a time very close to the wire, the outlining of the drift wire chambers with a long parallel beam, and the measurement of optical properties of scintillating plastic fibers. (author). 52 refs.; 76 figs.; 4 tabs

  10. Actuator-Assisted Calibration of Freehand 3D Ultrasound System.

    Science.gov (United States)

    Koo, Terry K; Silvia, Nathaniel

    2018-01-01

    Freehand three-dimensional (3D) ultrasound has been used independently of other technologies to analyze complex geometries or registered with other imaging modalities to aid surgical and radiotherapy planning. A fundamental requirement for all freehand 3D ultrasound systems is probe calibration. The purpose of this study was to develop an actuator-assisted approach to facilitate freehand 3D ultrasound calibration using point-based phantoms. We modified the mathematical formulation of the calibration problem to eliminate the need of imaging the point targets at different viewing angles and developed an actuator-assisted approach/setup to facilitate quick and consistent collection of point targets spanning the entire image field of view. The actuator-assisted approach was applied to a commonly used cross wire phantom as well as two custom-made point-based phantoms (original and modified), each containing 7 collinear point targets, and compared the results with the traditional freehand cross wire phantom calibration in terms of calibration reproducibility, point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time. Results demonstrated that the actuator-assisted single cross wire phantom calibration significantly improved the calibration reproducibility and offered similar point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time with respect to the freehand cross wire phantom calibration. On the other hand, the actuator-assisted modified "collinear point target" phantom calibration offered similar precision and accuracy when compared to the freehand cross wire phantom calibration, but it reduced the data acquisition time by 57%. It appears that both actuator-assisted cross wire phantom and modified collinear point target phantom calibration approaches are viable options for freehand 3D ultrasound calibration.

  11. Calibration between a Laser Range Scanner and an Industrial Robot Manipulator

    DEFF Research Database (Denmark)

    Andersen, Thomas Timm; Andersen, Nils Axel; Ravn, Ole

    2014-01-01

    In this paper we present a method for findingthe transformation between a laser scanner and a robotmanipulator. We present the design of a flat calibration targetthat can easily fit between a laser scanner and a conveyor belt,making the method easily implementable in a manufacturingline.We prove...... that the method works by simulating a range ofdifferent orientations of the target, and performs an extensivenumerical evaluation of the targets design parameters to estab-lish the optimal values as well as the worst-case accuracy ofthe method...

  12. The use of airborne laser data to calibrate satellite radar altimetry data over ice sheets

    DEFF Research Database (Denmark)

    Ekholm, Simon; Bamber, J.L.; Krabill, W.B.

    2002-01-01

    Satellite radar altimetry is the most important data source for ice sheet elevation modeling but it is well established that the accuracy of such data from satellite borne radar altimeters degrade seriously with increasing surface slope and level of roughness. A significant fraction of the slope......-precision airborne laser profiling data from the so-called Arctic Ice Mapping project as a tool to determine that bias and to calibrate the satellite altimetry. This is achieved by a simple statistical analysis of the airborne laser profiles, which defines the mean amplitude of the local surface undulations...

  13. Electromagnetic calibration system for sub-micronewton torsional thrust stand

    Science.gov (United States)

    Lam, J. K.; Koay, S. C.; Cheah, K. H.

    2017-12-01

    It is critical for a micropropulsion system to be evaluated. Thrust stands are widely recognised as the instrument to complete such tasks. This paper presents the development of an alternative electromagnetic calibration technique for thrust stands. Utilising the commercially made voice coils and permanent magnets, the proposed system is able to generate repeatable and also consistent steady-state calibration forces at over four orders of magnitude (30 - 23000 μN). The system is then used to calibrate a custom-designed torsional thrust stand, where its inherent ability in ease of setup is well demonstrated.

  14. The laser calibration of the ATLAS Tile Calorimeter during the LHC run 1

    Czech Academy of Sciences Publication Activity Database

    Abdallah, J.; Alexa, C.; Coutinho, Y.A.; Lokajíček, Miloš; Němeček, Stanislav

    2016-01-01

    Roč. 11, Oct (2016), 1-31, č. článku T10005. ISSN 1748-0221 R&D Projects: GA MŠk(CZ) LG15047; GA MŠk LM2015068 Institutional support: RVO:68378271 Keywords : electronics * readout * calorimeter * hadronic * calibration * laser * stability * ATLAS * data analysis method Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.220, year: 2016

  15. A primary standard for low-g shock calibration by laser interferometry

    Science.gov (United States)

    Sun, Qiao; Wang, Jian-lin; Hu, Hong-bo

    2014-07-01

    This paper presents a novel implementation of a primary standard for low-g shock acceleration calibration by laser interferometry based on rigid body collision at National Institute of Metrology, China. The mechanical structure of the standard device and working principles involved in the shock acceleration exciter, laser interferometers and virtual instruments are described. The novel combination of an electromagnetic exciter and a pneumatic exciter as the mechanical power supply of the standard device can deliver a wide range of shock acceleration levels. In addition to polyurethane rubber, two other types of material are investigated to ensure a wide selection of cushioning pads for shock pulse generation, with pulse shapes and data displayed. A heterodyne He-Ne laser interferometer is preferred for its precise and reliable measurement of shock acceleration while a homodyne one serves as a check standard. Some calibration results of a standard acceleration measuring chain are shown in company with the uncertainty evaluation budget. The expanded calibration uncertainty of shock sensitivity of the acceleration measuring chain is 0.8%, k = 2, with the peak acceleration range from 20 to 10 000 m s-2 and pulse duration from 0.5 to 10 ms. This primary shock standard can meet the traceability requirements of shock acceleration from various applications of industries from automobile to civil engineering and therefore is used for piloting the ongoing shock comparison of Technical Committee of Acoustics, Ultrasound and Vibration (TCAUV) of Asia Pacific Metrology Program (APMP), coded as APMP.AUV.V-P1.

  16. Gas characterization system operation, maintenance, and calibration plan

    International Nuclear Information System (INIS)

    Tate, D.D.

    1996-01-01

    This document details the responsibilities and requirements for operation, maintenance, and calibration of the Gas Characterization Systems (GCS) analytical instrumentation. It further, defines the division of responsibility between the Characterization Monitoring Development organization and Tank Farms Operations

  17. An Integrated Calibration Technique for Stereo Vision Systems (PREPRINT)

    Science.gov (United States)

    2010-03-01

    technique for stereo vision systems has been developed. To demonstrate and evaluate this calibration technique, multiple Wii Remotes (Wiimotes) from Nintendo ...from Nintendo were used to form stereo vision systems to perform 3D motion capture in real time. This integrated technique is a two-step process...Wiimotes) used in Nintendo Wii games. Many researchers have successfully dealt with the problem of camera calibration by taking images from a 2D

  18. Systematic Calibration for a Backpacked Spherical Photogrammetry Imaging System

    Science.gov (United States)

    Rau, J. Y.; Su, B. W.; Hsiao, K. W.; Jhan, J. P.

    2016-06-01

    A spherical camera can observe the environment for almost 720 degrees' field of view in one shoot, which is useful for augmented reality, environment documentation, or mobile mapping applications. This paper aims to develop a spherical photogrammetry imaging system for the purpose of 3D measurement through a backpacked mobile mapping system (MMS). The used equipment contains a Ladybug-5 spherical camera, a tactical grade positioning and orientation system (POS), i.e. SPAN-CPT, and an odometer, etc. This research aims to directly apply photogrammetric space intersection technique for 3D mapping from a spherical image stereo-pair. For this purpose, several systematic calibration procedures are required, including lens distortion calibration, relative orientation calibration, boresight calibration for direct georeferencing, and spherical image calibration. The lens distortion is serious on the ladybug-5 camera's original 6 images. Meanwhile, for spherical image mosaicking from these original 6 images, we propose the use of their relative orientation and correct their lens distortion at the same time. However, the constructed spherical image still contains systematic error, which will reduce the 3D measurement accuracy. Later for direct georeferencing purpose, we need to establish a ground control field for boresight/lever-arm calibration. Then, we can apply the calibrated parameters to obtain the exterior orientation parameters (EOPs) of all spherical images. In the end, the 3D positioning accuracy after space intersection will be evaluated, including EOPs obtained by structure from motion method.

  19. Regenerative laser system

    International Nuclear Information System (INIS)

    Biancardi, F.R.; Landerman, A.; Melikian, G.

    1975-01-01

    Regenerative apparatus for exhausting the working medium from the optical cavity of a laser and for supplying preheated diluent to the reaction chamber of a laser is disclosed. In an aftercooler thermal energy is exchanged between the working medium exhausted from the optical cavity and a cryogenic coolant which is subsequently utilized as the motive fluid for an ejector and as a diluent in the production of laser gas. Highly toxic and corrosive gases are condensed out of the working medium as the cryogenic coolant is evaporated and superheated. A preheater transfers additional heat to the diluent before the diluent enters the reaction chamber. (U.S.)

  20. Improving quality of laser scanning data acquisition through calibrated amplitude and pulse deviation measurement

    Science.gov (United States)

    Pfennigbauer, Martin; Ullrich, Andreas

    2010-04-01

    Newest developments in laser scanner technologies put surveyors in the position to comply with the ever increasing demand of high-speed, high-accuracy, and highly reliable data acquisition from terrestrial, mobile, and airborne platforms. Echo digitization in pulsed time-of-flight laser ranging has demonstrated its superior performance in the field of bathymetry and airborne laser scanning for more than a decade, however at the cost of somewhat time consuming off line post processing. State-of-the-art online waveform processing as implemented in RIEGL's V-Line not only saves users post-processing time to obtain true 3D point clouds, it also adds the assets of calibrated amplitude and reflectance measurement for data classification and pulse deviation determination for effective and reliable data validation. We present results from data acquisitions in different complex target situations.

  1. Vision system for dial gage torque wrench calibration

    Science.gov (United States)

    Aggarwal, Neelam; Doiron, Theodore D.; Sanghera, Paramjeet S.

    1993-11-01

    In this paper, we present the development of a fast and robust vision system which, in conjunction with the Dial Gage Calibration system developed by AKO Inc., will be used by the U.S. Army in calibrating dial gage torque wrenches. The vision system detects the change in the angular position of the dial pointer in a dial gage. The angular change is proportional to the applied torque. The input to the system is a sequence of images of the torque wrench dial gage taken at different dial pointer positions. The system then reports the angular difference between the different positions. The primary components of this vision system include modules for image acquisition, linear feature extraction and angle measurements. For each of these modules, several techniques were evaluated and the most applicable one was selected. This system has numerous other applications like vision systems to read and calibrate analog instruments.

  2. Radiometric calibration of the in-flight blackbody calibration system of the GLORIA interferometer

    Directory of Open Access Journals (Sweden)

    C. Monte

    2014-01-01

    Atmosphere is an airborne, imaging, infrared Fourier transform spectrometer that applies the limb-imaging technique to perform trace gas and temperature measurements in the Earth's atmosphere with three-dimensional resolution. To ensure the traceability of these measurements to the International Temperature Scale and thereby to an absolute radiance scale, GLORIA carries an on-board calibration system. Basically, it consists of two identical large-area and high-emissivity infrared radiators, which can be continuously and independently operated at two adjustable temperatures in a range from −50 °C to 0 °C during flight. Here we describe the radiometric and thermometric characterization and calibration of the in-flight calibration system at the Reduced Background Calibration Facility of the Physikalisch-Technische Bundesanstalt. This was performed with a standard uncertainty of less than 110 mK. Extensive investigations of the system concerning its absolute radiation temperature and spectral radiance, its temperature homogeneity and its short- and long-term stability are discussed. The traceability chain of these measurements is presented.

  3. Calibration of robotic drilling systems with a moving rail

    Directory of Open Access Journals (Sweden)

    Tian Wei

    2014-12-01

    Full Text Available Industrial robots are widely used in aircraft assembly systems such as robotic drilling systems. It is necessary to expand a robot’s working range with a moving rail. A method for improving the position accuracy of an automated assembly system with an industrial robot mounted on a moving rail is proposed. A multi-station method is used to control the robot in this study. The robot only works at stations which are certain positions defined on the moving rail. The calibration of the robot system is composed by the calibration of the robot and the calibration of the stations. The calibration of the robot is based on error similarity and inverse distance weighted interpolation. The calibration of the stations is based on a magnetic strip and a magnetic sensor. Validation tests were performed in this study, which showed that the accuracy of the robot system gained significant improvement using the proposed method. The absolute position errors were reduced by about 85% to less than 0.3 mm compared with the maximum nearly 2 mm before calibration.

  4. The GEO 600 laser system

    CERN Document Server

    Zawischa, I; Danzmann, K; Fallnich, C; Heurs, M; Nagano, S; Quetschke, V; Welling, H; Willke, B

    2002-01-01

    Interferometric gravitational wave detectors require high optical power, single frequency lasers with very good beam quality and high amplitude and frequency stability as well as high long-term reliability as input light source. For GEO 600 a laser system with these properties is realized by a stable planar, longitudinally pumped 12 W Nd:YAG rod laser which is injection-locked to a monolithic 800 mW Nd:YAG non-planar ring oscillator. Frequency control signals from the mode cleaners are fed to the actuators of the non-planar ring oscillator which determines the frequency stability of the system. The system power stabilization acts on the slave laser pump diodes which have the largest influence on the output power. In order to gain more output power, a combined Nd:YAG-Nd:YVO sub 4 system is scaled to more than 22 W.

  5. A portable, automated, inexpensive mass and balance calibration system

    International Nuclear Information System (INIS)

    Maxwell, S.L. III; Clark, J.P.

    1987-01-01

    Reliable mass measurements are essential for a nuclear production facility or process control laboratory. DOE Order 5630.2 requires that traceable standards be used to calibrate and monitor equipment used for nuclear material measurements. To ensure the reliability of mass measurements and to comply with DOE traceable requirements, a portable, automated mass and balance calibration system is used at the Savannah River Plant. Automation is achieved using an EPSON HX-20 notebook computer, which can be operated via RS232C interfacing to electronic balances or function with manual data entry if computer interfacing is not feasible. This economical, comprehensive, user-friendly system has three main functions in a mass measurement control program (MMCP): balance certification, calibration of mass standards, and daily measurement of traceable standards. The balance certification program tests for accuracy, precision, sensitivity, linearity, and cornerloading versus specific requirements. The mass calibration program allows rapid calibration of inexpensive mass standards traceable to certified Class S standards. This MMCP permits daily measurement of traceable standards to monitor the reliability of balances during routine use. The automated system verifies balance calibration, stores results for future use, and provides a printed control chart of the stored data. Another feature of the system permits three different weighing routines that accommodate our need for varying degrees of reliability in routine weighing operations. 1 ref

  6. CAMAC-controlled calibration system for nuclear reactor instruments

    International Nuclear Information System (INIS)

    McDowell, W.P.; Cornella, R.J.

    1977-01-01

    The hardware and the software which have been developed to implement a nuclear instrument calibration system for the Argonne National Laboratory ZPR-VI and ZPR-IX reactor complex are described. The system is implemented using an SEL-840 computer with its associated CAMAC crates and a hardware interface to generate input parameters and measure the required outputs on the instrument under test. Both linear and logarithmic instruments can be calibrated by the system and output parameters can be measured at various automatically selected values of ac line voltage. A complete report on each instrument is printed as a result of the calibration and out-of-tolerance readings are flagged. Operator interface is provided by a CAMAC-controlled Hazeltine terminal. The terminal display leads the operator through the complete calibration procedure. This computer-controlled system is a significant improvement over previously used methods of calibrating nuclear instruments since it reduces reactor downtime and allows rapid detection of long-term changes in instrument calibration

  7. A portable, automated, inexpensive mass and balance calibration system

    International Nuclear Information System (INIS)

    Maxwell, S.L. III; Clark, J.P.

    1987-01-01

    Reliable mass measurements are essential for a nuclear production facility or process control laboratory. DOE Order 5630.2 requires that traceable standards be used to calibrate and monitor equipment used for nuclear material measurements. To ensure the reliability of mass measurements and to comply with DOE traceability requirements, a portable, automated mass and balance calibration system is used at the Savannah River Plant. Automation is achieved using an EPSON HX-20 notebook computer, which can be operated via RS232C interfacing to electronic balances or function with manual data entry if computer interfacing is not feasible. This economical, comprehensive, user-friendly system has three main functions in a mass measurement control program (MMCP): balance certification, calibration of mass standards, and daily measurement of traceable standards. The balance certification program tests for accuracy, precision, sensitivity, linearity, and cornerloading versus specific requirements. The mass calibration program allows rapid calibration of inexpensive mass standards traceable to certified Class S standards. This MMCP permits daily measurement of traceable standards to monitor the reliability of balances during routine use. The automated system verifies balance calibration, stores results for future use, and provides a printed control chart of the stored data. Another feature of the system permits three different weighing routines that accommodate their need for varying degrees of reliability in routine weighing operations

  8. The Importance of Calibration on Digital Radioscopy System

    International Nuclear Information System (INIS)

    Noorhazleena Azaman; Abdul Razak Hamzah; Sapizah Rahim

    2011-01-01

    Radiography testing is one of the non-destructive testing methods where it is used to detect discontinuities in a material by using x-ray and gamma ray as a sources of radiation. Mobile digital radioscopy system (MDRS) is act as a detector or medium to capture and convert the image in a real time and the image produced can view directly from the computer connected to the MDRS. Calibration is one of the factors that we need to consider in order to get the image and see in a high resolution and good contrast. The advantage of calibration in MDRS is to reduce and avoid from the noise. Calibration is not stable and the imaging system must be calibrated periodically. It is also as an alternative to the radiographic film to reduce and saving cost and time with considerable saving in running cost and processing time. (author)

  9. Nova laser alignment control system

    International Nuclear Information System (INIS)

    Van Arsdall, P.J.; Holloway, F.W.; McGuigan, D.L.; Shelton, R.T.

    1984-01-01

    Alignment of the Nova laser requires control of hundreds of optical components in the ten beam paths. Extensive application of computer technology makes daily alignment practical. The control system is designed in a manner which provides both centralized and local manual operator controls integrated with automatic closed loop alignment. Menudriven operator consoles using high resolution color graphics displays overlaid with transport touch panels allow laser personnel to interact efficiently with the computer system. Automatic alignment is accomplished by using image analysis techniques to determine beam references points from video images acquired along the laser chain. A major goal of the design is to contribute substantially to rapid experimental turnaround and consistent alignment results. This paper describes the computer-based control structure and the software methods developed for aligning this large laser system

  10. A Statistic-Based Calibration Method for TIADC System

    Directory of Open Access Journals (Sweden)

    Kuojun Yang

    2015-01-01

    Full Text Available Time-interleaved technique is widely used to increase the sampling rate of analog-to-digital converter (ADC. However, the channel mismatches degrade the performance of time-interleaved ADC (TIADC. Therefore, a statistic-based calibration method for TIADC is proposed in this paper. The average value of sampling points is utilized to calculate offset error, and the summation of sampling points is used to calculate gain error. After offset and gain error are obtained, they are calibrated by offset and gain adjustment elements in ADC. Timing skew is calibrated by an iterative method. The product of sampling points of two adjacent subchannels is used as a metric for calibration. The proposed method is employed to calibrate mismatches in a four-channel 5 GS/s TIADC system. Simulation results show that the proposed method can estimate mismatches accurately in a wide frequency range. It is also proved that an accurate estimation can be obtained even if the signal noise ratio (SNR of input signal is 20 dB. Furthermore, the results obtained from a real four-channel 5 GS/s TIADC system demonstrate the effectiveness of the proposed method. We can see that the spectra spurs due to mismatches have been effectively eliminated after calibration.

  11. The KamLAND full-volume calibration system

    Energy Technology Data Exchange (ETDEWEB)

    Berger, B E [Department of Physics, Colorado State University, Fort Collins, Colorado 80523 (United States); Busenitz, J; Classen, T; Keefer, G; McKee, D; Piepke, A [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, Alabama 35487 (United States); Decowski, M P; Elor, G; Frank, A; Freedman, S J; Fujikawa, B K; Galloway, M; Gray, F; Hsu, L; Ichimura, K; Kadel, R; Lendvai, C; O' Donnell, T [Physics Department, University of California, Berkeley and Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Dwyer, D A [W. K. Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California 91125 (United States); Heeger, K M [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)] (and others)

    2009-04-15

    We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.

  12. The KamLAND Full-Volume Calibration System

    Energy Technology Data Exchange (ETDEWEB)

    KamLAND Collaboration; Berger, B. E.; Busenitz, J.; Classen, T.; Decowski, M. P.; Dwyer, D. A.; Elor, G.; Frank, A.; Freedman, S. J.; Fujikawa, B. K.; Galloway, M.; Gray, F.; Heeger, K. M.; Hsu, L.; Ichimura, K.; Kadel, R.; Keefer, G.; Lendvai, C.; McKee, D.; O' Donnell, T.; Piepke, A.; Steiner, H. M.; Syversrud, D.; Wallig, J.; Winslow, L. A.; Ebihara, T.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Owada, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Tamae, K.; Yoshida, S.; Kozlov, A.; Murayama, H.; Grant, C.; Leonard, D. S.; Luk, K.-B.; Jillings, C.; Mauger, C.; McKeown, R. D.; Zhang, C.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Piquemal, F.; Ricol, J.-S.

    2009-03-05

    We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.

  13. A machine vision system for the calibration of digital thermometers

    International Nuclear Information System (INIS)

    Vázquez-Fernández, Esteban; Dacal-Nieto, Angel; González-Jorge, Higinio; Alvarez-Valado, Victor; Martín, Fernando; Formella, Arno

    2009-01-01

    Automation is a key point in many industrial tasks such as calibration and metrology. In this context, machine vision has shown to be a useful tool for automation support, especially when there is no other option available. A system for the calibration of portable measurement devices has been developed. The system uses machine vision to obtain the numerical values shown by displays. A new approach based on human perception of digits, which works in parallel with other more classical classifiers, has been created. The results show the benefits of the system in terms of its usability and robustness, obtaining a success rate higher than 99% in display recognition. The system saves time and effort, and offers the possibility of scheduling calibration tasks without excessive attention by the laboratory technicians

  14. A primary standard for low-g shock calibration by laser interferometry

    International Nuclear Information System (INIS)

    Sun, Qiao; Wang, Jian-lin; Hu, Hong-bo

    2014-01-01

    This paper presents a novel implementation of a primary standard for low-g shock acceleration calibration by laser interferometry based on rigid body collision at National Institute of Metrology, China. The mechanical structure of the standard device and working principles involved in the shock acceleration exciter, laser interferometers and virtual instruments are described. The novel combination of an electromagnetic exciter and a pneumatic exciter as the mechanical power supply of the standard device can deliver a wide range of shock acceleration levels. In addition to polyurethane rubber, two other types of material are investigated to ensure a wide selection of cushioning pads for shock pulse generation, with pulse shapes and data displayed. A heterodyne He–Ne laser interferometer is preferred for its precise and reliable measurement of shock acceleration while a homodyne one serves as a check standard. Some calibration results of a standard acceleration measuring chain are shown in company with the uncertainty evaluation budget. The expanded calibration uncertainty of shock sensitivity of the acceleration measuring chain is 0.8%, k = 2, with the peak acceleration range from 20 to 10 000 m s −2  and pulse duration from 0.5 to 10 ms. This primary shock standard can meet the traceability requirements of shock acceleration from various applications of industries from automobile to civil engineering and therefore is used for piloting the ongoing shock comparison of Technical Committee of Acoustics, Ultrasound and Vibration (TCAUV) of Asia Pacific Metrology Program (APMP), coded as APMP.AUV.V-P1. (paper)

  15. Aferição dos equipamentos de laser de baixa intensidade Calibration of low-level laser therapy equipment

    Directory of Open Access Journals (Sweden)

    Thiago Y. Fukuda

    2010-08-01

    Full Text Available CONTEXTUALIZAÇÃO: A laserterapia de baixa intensidade (LBI vem sendo cada vez mais utilizada, porém ainda não há consenso na literatura quanto ao tempo em que os equipamentos devem ser submetidos à aferição ou calibragem. OBJETIVO: Analisar a potência média real (PmR dos equipamentos de LBI na região da Grande São Paulo. MÉTODOS: Para análise dos equipamentos, utilizou-se um potenciômetro (Lasercheck, próprio para aferição de equipamentos contínuos, o qual foi programado com dados referentes ao comprimento de onda do laser a ser avaliado, obtendo-se assim a PmR emitida. Os equipamentos foram analisados de duas formas: uma, com o LBI desaquecido, e outra, após 10 minutos de uso (aquecido, sendo que três análises foram feitas para cada condição. A caneta emissora foi acoplada ao potenciômetro, o qual fornecia a PmR emitida pelo LBI. Todos os dados e informações referentes à aplicação do laser foram coletados por um questionário respondido pelos responsáveis. RESULTADOS: Os 60 equipamentos avaliados mostraram déficit na PmR com os equipamentos desaquecidos e aquecidos. A análise estatística (ANOVA mostrou diminuição significativa (PBACKGROUND: Despite the increase in the use of low-level laser therapy (LLLT, there is still a lack of consensus in the literature regarding how often the equipment must be calibrated. OBJECTIVE: To evaluate the real average power of LLLT devices in the Greater São Paulo area. METHODS: For the evaluation, a LaserCheck power meter designed to calibrate continuous equipment was used. The power meter was programmed with data related to the laser's wavelength to gauge the real average power being emitted. The LLLT devices were evaluated in two ways: first with the device cooled down and then with the device warmed up for 10 minutes. For each condition, three tests were performed. The laser probe was aligned with the power meter, which provided the real average power being emitted by the

  16. Development and application of a calibration technique for laser ablation - ICP - MS

    Energy Technology Data Exchange (ETDEWEB)

    Boue-Bigne, F

    2000-08-20

    Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) is a powerful analytical technique for the direct elemental analysis of solid samples, with spatial resolution down to a few microns. However, calibration remains the limiting factor in obtaining quantitative analysis by LA-ICP-MS for a wide range of sample types. No universal method exists as yet and the ones that are currently used tend to employ matrix-matched solid standards. Matrix-matched solid standards are not available for many types of sample, such as polymers, biological materials, fluid inclusions, etc. The need for a universal method of calibration that involves standards that are easy to prepare and suitable for any type of sample is required. Additional to matrix-matching, internal standards are widely used in LA-ICP-MS for quantitative analyses. The internal standard compensates for the different ablation yields from the sample and the standard and for the laser shot-to-shot variation. Given that the use of an internal standard is required to obtain reliable results, the need for matrix-matching might be regarded as questionable. This project has focused on the development and application of a new method of calibration for LA-ICP-MS. It involves the use of aqueous standards whose absorption characteristics are modified by the addition of a chromophore to the solution. Additives were selected for ablation with KrF excimer, and Nd:YAG lasers. The influence of the additive concentration on the ablation yield was investigated for different laser energies. Response curves were obtained showing that as the additive concentration was increased, less energy was required to ablate the modified standard solutions efficiently. A general procedure was then defined for the preparation and use of the modified standard solutions for a given sample. The new method of calibration was used for the quantitative analysis of different sample types: low density polyethylene (LDPE), polyketone (PK

  17. Development and application of a calibration technique for laser ablation - ICP - MS

    International Nuclear Information System (INIS)

    Boue-Bigne, F.

    2000-01-01

    Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) is a powerful analytical technique for the direct elemental analysis of solid samples, with spatial resolution down to a few microns. However, calibration remains the limiting factor in obtaining quantitative analysis by LA-ICP-MS for a wide range of sample types. No universal method exists as yet and the ones that are currently used tend to employ matrix-matched solid standards. Matrix-matched solid standards are not available for many types of sample, such as polymers, biological materials, fluid inclusions, etc. The need for a universal method of calibration that involves standards that are easy to prepare and suitable for any type of sample is required. Additional to matrix-matching, internal standards are widely used in LA-ICP-MS for quantitative analyses. The internal standard compensates for the different ablation yields from the sample and the standard and for the laser shot-to-shot variation. Given that the use of an internal standard is required to obtain reliable results, the need for matrix-matching might be regarded as questionable. This project has focused on the development and application of a new method of calibration for LA-ICP-MS. It involves the use of aqueous standards whose absorption characteristics are modified by the addition of a chromophore to the solution. Additives were selected for ablation with KrF excimer, and Nd:YAG lasers. The influence of the additive concentration on the ablation yield was investigated for different laser energies. Response curves were obtained showing that as the additive concentration was increased, less energy was required to ablate the modified standard solutions efficiently. A general procedure was then defined for the preparation and use of the modified standard solutions for a given sample. The new method of calibration was used for the quantitative analysis of different sample types: low density polyethylene (LDPE), polyketone (PK

  18. Laser Pyro System Standardization and Man Rating

    Science.gov (United States)

    Brown, Christopher W.

    2004-01-01

    This viewgraph presentation reviews an X-38 laser pyro system standardization system designed for a new manned rated program. The plans to approve this laser initiation system and preliminary ideas for this system are also provided.

  19. The calibration procedures in the Studsvik standardized personnel dosimetry system

    International Nuclear Information System (INIS)

    Widell, C.O.

    1978-01-01

    Every large nuclear installation in Sweden reads its own personnel TLDs. In order to supervise this decentralized reading of dose meters, the TLD readers are connected by telephone lines to a central computer for dose registration. This computer is used both for registering the personnel doses and for checking the TLD readers. This checking is performed by the use of pre-irradiated calibration dose meters which are always used when a batch of personnel dose meters are read. The pre-irradiated dose meters are either irradiated using 137 Cs to various doses up to 100mSv(10000mrem) or using a 90 Sr source in a reference dose irradiator to a dose equal to 3mSv(300mrem) from a 137 Cs source. The results from the reading of the pre-irradiated dose meters are processed by the computer and a calibration factor is calculated. The calibration factor is automatically used to calculate the doses to the personnel TLD's. However, if the calibration factor deviates by more than 10% from the previously used factor, this fact is shown to the operator - who then has to decide what calibration factor is going to be used. This calibration and supervisory procedure together with the safety interlocks in the TLD readers has resulted in a very reliable and accurate dosimetry system. (author)

  20. Calibration of a PIXE system for analysis of environmental aerosols

    International Nuclear Information System (INIS)

    Aldape, F.; Diaz, R.V.; Anguiano, G.; Flores M, J.

    1991-04-01

    The results of the calibration of the PIXE system for analysis of environmental aerosols in the CNM is presented. The system was calibrated in order to lead to the project study of environmental aerosols using PIXE from the qualitative dimension to the quantitative one. Part of this work it was carried out in collaboration with the expert of the IAEA Dr. D. Crumpton. The calibration of the system it was achieved bombarding thin targets of well-known composition with protons of 2.5 MeV. Using this technique it was determined the absolute elementary concentration in samples of atmospheric aerosols. As an example the calculation of the lead concentration in one of them whose result was of 662 ± 49 ng m -3 is presented. This value agrees with the measurements made in the Crocker Nuclear Lab of the UCD. Its are also discussed the reproducibility and precision of the used technique. (Author)

  1. Traveling wave laser system

    International Nuclear Information System (INIS)

    Gregg, D.W.; Kidder, R.E.; Biehl, A.T.

    1975-01-01

    A method is described for generating a traveling wave laser pulse of almost unlimited energy content wherein a gain medium is pumped into a traveling wave mode, the traveling wave moving at essentially the velocity of light to generate an amplifying region or zone which moves through the medium at the velocity of light in the presence of directed stimulating radiation, thereby generating a traveling coherent, directed radiation pulse moving with the amplification zone through the gain medium. (U.S.)

  2. Underwater laser imaging system (UWLIS)

    Energy Technology Data Exchange (ETDEWEB)

    DeLong, M. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    Practical limitations with underwater imaging systems area reached when the noise in the back scattered radiation generated in the water between the imaging system and the target obscures the spatial contrast and resolution necessary for target discovery and identification. The advent of high power lasers operating in the blue-green portion of the visible spectrum (oceanic transmission window) has led to improved experimental illumination systems for underwater imaging. Range-gated and synchronously scanned devices take advantage of the unique temporal and spatial coherence properties of laser radiation, respectively, to overcome the deleterious effects of common volume back scatter.

  3. Geometric calibration method for multiple head cone beam SPECT systems

    International Nuclear Information System (INIS)

    Rizo, Ph.; Grangeat, P.; Guillemaud, R.; Sauze, R.

    1993-01-01

    A method is presented for performing geometric calibration on Single Photon Emission Tomography (SPECT) cone beam systems with multiple cone beam collimators, each having its own orientation parameters. This calibration method relies on the fact that, in tomography, for each head, the relative position of the rotation axis and of the collimator does not change during the acquisition. In order to ensure the method stability, the parameters to be estimated in intrinsic parameters and extrinsic parameters are separated. The intrinsic parameters describe the acquisition geometry and the extrinsic parameters position of the detection system with respect to the rotation axis. (authors) 3 refs

  4. Calibration of the ISOLDE acceleration voltage using a high-precision voltage divider and applying collinear fast beam laser spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Krieger, A., E-mail: kriegea@uni-mainz.d [Institut fuer Kernchemie, Johannes Gutenberg, Universitaet Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany); Geppert, Ch. [Institut fuer Kernchemie, Johannes Gutenberg, Universitaet Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung, 64291 Darmstadt (Germany); Catherall, R. [CERN, CH-1211 Geneve 23 (Switzerland); Hochschulz, F. [Institut fuer Kernphysik, Universitaet Muenster, 48149 Muenster (Germany); Kraemer, J.; Neugart, R. [Institut fuer Kernchemie, Johannes Gutenberg, Universitaet Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany); Rosendahl, S. [Institut fuer Kernphysik, Universitaet Muenster, 48149 Muenster (Germany); Schipper, J.; Siesling, E. [CERN, CH-1211 Geneve 23 (Switzerland); Weinheimer, Ch. [Institut fuer Kernphysik, Universitaet Muenster, 48149 Muenster (Germany); Yordanov, D.T. [Max-Planck-Institut fuer Kernphysik, 69117 Heidelberg (Germany); Noertershaeuser, W. [Institut fuer Kernchemie, Johannes Gutenberg, Universitaet Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung, 64291 Darmstadt (Germany)

    2011-03-11

    A high-voltage divider with accuracy at the ppm level and collinear laser spectroscopy were used to calibrate the high-voltage installation at the radioactive ion beam facility ISOLDE at CERN. The accurate knowledge of this voltage is particularly important for collinear laser spectroscopy measurements. Beam velocity measurements using frequency-comb based collinear laser spectroscopy agree with the new calibration. Applying this, one obtains consistent results for isotope shifts of stable magnesium isotopes measured using collinear spectroscopy and laser spectroscopy on laser-cooled ions in a trap. The long-term stability and the transient behavior during recovery from a voltage dropout were investigated for the different power supplies currently applied at ISOLDE.

  5. Model calibration and beam control systems for storage rings

    International Nuclear Information System (INIS)

    Corbett, W.J.; Lee, M.J.; Ziemann, V.

    1993-04-01

    Electron beam storage rings and linear accelerators are rapidly gaining worldwide popularity as scientific devices for the production of high-brightness synchrotron radiation. Today, everybody agrees that there is a premium on calibrating the storage ring model and determining errors in the machine as soon as possible after the beam is injected. In addition, the accurate optics model enables machine operators to predictably adjust key performance parameters, and allows reliable identification of new errors that occur during operation of the machine. Since the need for model calibration and beam control systems is common to all storage rings, software packages should be made that are portable between different machines. In this paper, we report on work directed toward achieving in-situ calibration of the optics model, detection of alignment errors, and orbit control techniques, with an emphasis on developing a portable system incorporating these tools

  6. Calibration methods for ECE systems with microwave sources

    International Nuclear Information System (INIS)

    Tubbing, B.J.D.; Kissel, S.E.

    1987-01-01

    The authors investigated the feasibility of two methods for calibration of electron cyclotron emission (ECE) systems, both based on the use of a microwave source. In the first method -called the Antenna Pattern Integration (API) method - the microwave source is scanned in space, so as to simulate a large - area - blackbody -source. In the second method -called the Untuned Cavity (UC) method -an untuned cavity, fed by the microwave source, is used to simulate a blackbody. For both methods, the hardware required to perform partly automated calibrations was developed. The microwave based methods were compared with a large area blackbody calibration on two different ECE systems, a Michelson interferometer and a grating polychromator. The API method was found to be more successful than the UC method. (author)

  7. Calibration of NASA Turbulent Air Motion Measurement System

    Science.gov (United States)

    Barrick, John D. W.; Ritter, John A.; Watson, Catherine E.; Wynkoop, Mark W.; Quinn, John K.; Norfolk, Daniel R.

    1996-01-01

    A turbulent air motion measurement system (TAMMS) was integrated onboard the Lockheed 188 Electra airplane (designated NASA 429) based at the Wallops Flight Facility in support of the NASA role in global tropospheric research. The system provides air motion and turbulence measurements from an airborne platform which is capable of sampling tropospheric and planetary boundary-layer conditions. TAMMS consists of a gust probe with free-rotating vanes mounted on a 3.7-m epoxy-graphite composite nose boom, a high-resolution inertial navigation system (INS), and data acquisition system. A variation of the tower flyby method augmented with radar tracking was implemented for the calibration of static pressure position error and air temperature probe. Additional flight calibration maneuvers were performed remote from the tower in homogeneous atmospheric conditions. System hardware and instrumentation are described and the calibration procedures discussed. Calibration and flight results are presented to illustrate the overall ability of the system to determine the three-component ambient wind fields during straight and level flight conditions.

  8. Laser cutting of irregular shape object based on stereo vision laser galvanometric scanning system

    Science.gov (United States)

    Qi, Li; Zhang, Yixin; Wang, Shun; Tang, Zhiqiang; Yang, Huan; Zhang, Xuping

    2015-05-01

    Irregular shape objects with different 3-dimensional (3D) appearances are difficult to be shaped into customized uniform pattern by current laser machining approaches. A laser galvanometric scanning system (LGS) could be a potential candidate since it can easily achieve path-adjustable laser shaping. However, without knowing the actual 3D topography of the object, the processing result may still suffer from 3D shape distortion. It is desirable to have a versatile auxiliary tool that is capable of generating 3D-adjusted laser processing path by measuring the 3D geometry of those irregular shape objects. This paper proposed the stereo vision laser galvanometric scanning system (SLGS), which takes the advantages of both the stereo vision solution and conventional LGS system. The 3D geometry of the object obtained by the stereo cameras is used to guide the scanning galvanometers for 3D-shape-adjusted laser processing. In order to achieve precise visual-servoed laser fabrication, these two independent components are integrated through a system calibration method using plastic thin film target. The flexibility of SLGS has been experimentally demonstrated by cutting duck feathers for badminton shuttle manufacture.

  9. Quantitative analysis of titanium concentration using calibration-free laser-induced breakdown spectroscopy (LIBS)

    Science.gov (United States)

    Zaitun; Prasetyo, S.; Suliyanti, M. M.; Isnaeni; Herbani, Y.

    2018-03-01

    Laser-induced breakdown spectroscopy (LIBS) can be used for quantitative and qualitative analysis. Calibration-free LIBS (CF-LIBS) is a method to quantitatively analyze concentration of elements in a sample in local thermodynamic equilibrium conditions without using available matrix-matched calibration. In this study, we apply CF-LIBS for quantitative analysis of Ti in TiO2 sample. TiO2 powder sample was mixed with polyvinyl alcohol and formed into pellets. An Nd:YAG pulsed laser at a wavelength of 1064 nm was focused onto the sample to generate plasma. The spectrum of plasma was recorded using spectrophotometer then compared to NIST spectral line to determine energy levels and other parameters. The value of plasma temperature obtained using Boltzmann plot is 8127.29 K and electron density from calculation is 2.49×1016 cm-3. Finally, the concentration of Ti in TiO2 sample from this study is 97% that is in proximity with the sample certificate.

  10. The ALICE Silicon Pixel Detector Control and Calibration Systems

    CERN Document Server

    Calì, Ivan Amos; Manzari, Vito; Stefanini, Giorgio

    2008-01-01

    The work presented in this thesis was carried out in the Silicon Pixel Detector (SPD) group of the ALICE experiment at the Large Hadron Collider (LHC). The SPD is the innermost part (two cylindrical layers of silicon pixel detec- tors) of the ALICE Inner Tracking System (ITS). During the last three years I have been strongly involved in the SPD hardware and software development, construction and commissioning. This thesis is focused on the design, development and commissioning of the SPD Control and Calibration Systems. I started this project from scratch. After a prototyping phase now a stable version of the control and calibration systems is operative. These systems allowed the detector sectors and half-barrels test, integration and commissioning as well as the SPD commissioning in the experiment. The integration of the systems with the ALICE Experiment Control System (ECS), DAQ and Trigger system has been accomplished and the SPD participated in the experimental December 2007 commissioning run. The complex...

  11. In-situ calibration: migrating control system IP module calibration from the bench to the storage ring

    International Nuclear Information System (INIS)

    Weber, Jonah M.; Chin, Michael

    2002-01-01

    The Control System for the Advanced Light Source (ALS) at Lawrence Berkeley National Lab (LBNL) uses in-house designed IndustryPack(registered trademark) (IP) modules contained in compact PCI (cPCI) crates with 16-bit analog I/O to control instrumentation. To make the IP modules interchangeable, each module is calibrated for gain and offset compensation. We initially developed a method of verifying and calibrating the IP modules in a lab bench test environment using a PC with LabVIEW. The subsequent discovery that the ADCs have significant drift characteristics over periods of days of installed operation prompted development of an ''in-situ'' calibration process--one in which the IP modules can be calibrated without removing them from the cPCI crates in the storage ring. This paper discusses the original LabVIEW PC calibration and the migration to the proposed in-situ EPICS control system calibration

  12. Remote quantitative analysis of minerals based on multispectral line-calibrated laser-induced breakdown spectroscopy (LIBS).

    Science.gov (United States)

    Wan, Xiong; Wang, Peng

    2014-01-01

    Laser-induced breakdown spectroscopy (LIBS) is a feasible remote sensing technique used for mineral analysis in some unapproachable places where in situ probing is needed, such as analysis of radioactive elements in a nuclear leak or the detection of elemental compositions and contents of minerals on planetary and lunar surfaces. Here a compact custom 15 m focus optical component, combining a six times beam expander with a telescope, has been built, with which the laser beam of a 1064 nm Nd ; YAG laser is focused on remote minerals. The excited LIBS signals that reveal the elemental compositions of minerals are collected by another compact single lens-based signal acquisition system. In our remote LIBS investigations, the LIBS spectra of an unknown ore have been detected, from which the metal compositions are obtained. In addition, a multi-spectral line calibration (MSLC) method is proposed for the quantitative analysis of elements. The feasibility of the MSLC and its superiority over a single-wavelength determination have been confirmed by comparison with traditional chemical analysis of the copper content in the ore.

  13. Confinement Vessel Assay System: Calibration and Certification Report

    Energy Technology Data Exchange (ETDEWEB)

    Frame, Katherine C. [Los Alamos National Laboratory; Bourne, Mark M. [Los Alamos National Laboratory; Crooks, William J. [Los Alamos National Laboratory; Evans, Louise [Los Alamos National Laboratory; Gomez, Cipriano [Retired CMR-OPS: OPERATIONS; Mayo, Douglas R. [Los Alamos National Laboratory; Miko, David K. [Los Alamos National Laboratory; Salazar, William R. [Los Alamos National Laboratory; Stange, Sy [Los Alamos National Laboratory; Vigil, Georgiana M. [Los Alamos National Laboratory

    2012-07-17

    Los Alamos National Laboratory has a number of spherical confinement vessels (CVs) remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1 to 2 inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. The Confinement Vessel Assay System (CVAS) was developed to measure the amount of SNM in CVs before and after cleanout. Prior to cleanout, the system will be used to perform a verification measurement of each vessel. After cleanout, the system will be used to perform safeguards-quality assays of {le} 100-g {sup 239}Pu equivalent in a vessel for safeguards termination. The system was calibrated in three different mass regions (low, medium, and high) to cover the entire plutonium mass range that will be assayed. The low mass calibration and medium mass calibration were verified for material positioned in the center of an empty vessel. The systematic uncertainty due to position bias was estimated using an MCNPX model to simulate the response of the system to material localized at various points along the inner surface of the vessel. The background component due to cosmic ray spallation was determined by performing measurements of an empty vessel and comparing to measurements in the same location with no vessel present. The CVAS has been tested and calibrated in preparation for verification and safeguards measurements of CVs before and after cleanout.

  14. Confinement Vessel Assay System: Calibration and Certification Report

    International Nuclear Information System (INIS)

    Frame, Katherine C.; Bourne, Mark M.; Crooks, William J.; Evans, Louise; Gomez, Cipriano; Mayo, Douglas R.; Miko, David K.; Salazar, William R.; Stange, Sy; Vigil, Georgiana M.

    2012-01-01

    Los Alamos National Laboratory has a number of spherical confinement vessels (CVs) remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1 to 2 inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. The Confinement Vessel Assay System (CVAS) was developed to measure the amount of SNM in CVs before and after cleanout. Prior to cleanout, the system will be used to perform a verification measurement of each vessel. After cleanout, the system will be used to perform safeguards-quality assays of (le) 100-g 239 Pu equivalent in a vessel for safeguards termination. The system was calibrated in three different mass regions (low, medium, and high) to cover the entire plutonium mass range that will be assayed. The low mass calibration and medium mass calibration were verified for material positioned in the center of an empty vessel. The systematic uncertainty due to position bias was estimated using an MCNPX model to simulate the response of the system to material localized at various points along the inner surface of the vessel. The background component due to cosmic ray spallation was determined by performing measurements of an empty vessel and comparing to measurements in the same location with no vessel present. The CVAS has been tested and calibrated in preparation for verification and safeguards measurements of CVs before and after cleanout.

  15. Calibration of the central jet chamber of the OPAL detector with UV laser beams: Methods and results on jet chamber prototypes (FSP)

    International Nuclear Information System (INIS)

    Hauschild, M.

    1988-11-01

    The central tracking device of the OPAL experiment at the LEP e + e - -collider consists of a pictorial jet chamber with a diameter of 4 m and 4 m length. The calibration of such a large detector is performed by the help of a UV laser system generating straight tracks even in the presence of magnetic fields. Intensive investigations of the laser calibration power and performance were done at the Full Scale Prototype (FSP) of the OPAL jet chamber. Laser double tracks with a precisely known distance are used to determine the drift velocity with an accuracy of 0.1%. From the measured deviations of a straight laser track electronic time offsets, wire positions and field distortions are derived. These calibration constants were applied to correct the measured drift times of test beam events. The sagitta and momentum resolutions of the thus corrected tracks have been obtained in the range from 6 GeV/c to 50 GeV/c. Extrapolating the results to the final OPAL jet chamber, a momentum resolution of σ-p/p = 6% is expected for 50 GeV/c tracks in a magnetic field of 4 kG. (orig.) [de

  16. Study and Development of a Laser Based Alignment System

    CERN Multimedia

    Stern, G

    2014-01-01

    CLIC (Compact Linear Collider) has tight requirements regarding pre-alignment of beam related components: 10 µm accuracy over a sliding window of 200 m along the 20 km of linac. To perform such an alignment, a new system is proposed combining laser beam as straight line reference and camera/shutter assemblies as sensors. The poster describes the alignment system and shows results regarding laser pointing stability with respect to time, shutter type, distance and environment. These results give a frame for future building and calibrating of sensors.

  17. Calibration, monitoring, and control of complex detector systems

    International Nuclear Information System (INIS)

    Breidenbach, M.

    1981-01-01

    LEP detectors will probably be complex devices having tens of subsystems; some subsystems having perhaps tens of thousands of channels. Reasonable design goals for such a detector will include economic use of money and people, rapid and reliable calibration and monitoring of the detector, and simple control and operation of the device. The synchronous operation of an e + e - storage ring, coupled with its relatively low interaction rate, allow the design of simple circuits for time and charge measurements. These circuits, and more importantly, the basic detector channels, can usually be tested and calibrated by signal injection into the detector. Present detectors utilize semi-autonomous controllers which collect such calibration data and calculate statistics as well as control sparse data scans. Straightforward improvements in programming technology should move the entire calibration into these local controllers, so that calibration and testing time will be a constant independent of the number of channels in a system. Considerable programming effort may be saved by emphasizing the similarities of the subsystems, so that the subsystems can be described by a reasonable database and general purpose calibration and test routines can be used. Monitoring of the apparatus will probably continue to be of two classes: 'passive' histogramming of channel occupancies and other more complex combinations of the data; and 'active' injection of test patterns and calibration signals during a run. The relative importance of active monitoring will increase for the low data rates expected off resonances at high s. Experience at SPEAR and PEP is used to illustrate these approaches. (Auth.)

  18. Calibration, Monitoring, and Control of Complex Detector Systems

    Science.gov (United States)

    Breidenbach, M.

    1981-04-01

    LEP Detectors will probably be complex devices having tens of subsystems; some subsystems having perhaps tens of thousands of channels. Reasonable design goals for such a detector will include economic use of money and people, rapid and reliable calibration and monitoring of the detector, and simple control and operation of the device. The synchronous operation of an e+e- storage ring, coupled with its relatively low interaction rate, allow the design of simple circuits for time and charge measurements. These circuits, and more importantly, the basic detector channels, can usually be tested and calibrated by signal injection into the detector. Present detectors utilize semi-autonomous controllers which collect such calibration data and calculate statistics as well as control sparse data scans. Straightforward improvements in programming technology should move the entire calibration into these local controllers, so that calibration and testing time will be a constant independent of the number of channels in a system. Considerable programming effort may be saved by emphasizing the similarities of the subsystems, so that the subsystems can be described by a reasonable database and general purpose calibration and test routines can be used. Monitoring of the apparatus will probably continue to be of two classes: "passive" histogramming of channel occupancies and other more complex combinations of the data; and "active" injection of test patterns and calibration signals during a run. The relative importance of active monitoring will increase for the low data rates expected off resonances at high s. Experience at SPEAR and PEP is used to illustrate these approaches.

  19. Development of automatic laser welding system

    International Nuclear Information System (INIS)

    Ohwaki, Katsura

    2002-01-01

    Laser are a new production tool for high speed and low distortion welding and applications to automatic welding lines are increasing. IHI has long experience of laser processing for the preservation of nuclear power plants, welding of airplane engines and so on. Moreover, YAG laser oscillators and various kinds of hardware have been developed for laser welding and automation. Combining these welding technologies and laser hardware technologies produce the automatic laser welding system. In this paper, the component technologies are described, including combined optics intended to improve welding stability, laser oscillators, monitoring system, seam tracking system and so on. (author)

  20. Seismic margins and calibration of piping systems

    International Nuclear Information System (INIS)

    Shieh, L.C.; Tsai, N.C.; Yang, M.S.; Wong, W.L.

    1985-01-01

    The Seismic Safety Margins Research Program (SSMRP) is a US Nuclear Regulatory Commission-funded, multiyear program conducted by Lawrence Livermore National Laboratory (LLNL). Its objective is to develop a complete, fully coupled analysis procedure for estimating the risk of earthquake-induced radioactive release from a commercial nuclear power plant and to determine major contributors to the state-of-the-art seismic and systems analysis process and explicitly includes the uncertainties in such a process. The results will be used to improve seismic licensing requirements for nuclear power plants. In Phase I of SSMRP, the overall seismic risk assessment methodology was developed and assembled. The application of this methodology to the seismic PRA (Probabilistic Risk Assessment) at the Zion Nuclear Power Plant has been documented. This report documents the method deriving response factors. The response factors, which relate design calculated responses to best estimate values, were used in the seismic response determination of piping systems for a simplified seismic probablistic risk assessment. 13 references, 31 figures, 25 tables

  1. On the efficiency calibration of a drum waste assay system

    CERN Document Server

    Dinescu, L; Cazan, I L; Macrin, R; Caragheorgheopol, G; Rotarescu, G

    2002-01-01

    The efficiency calibration of a gamma spectroscopy waste assay system, constructed by IFIN-HH, was performed. The calibration technique was based on the assumption of a uniform distribution of the source activity in the drum and also a uniform sample matrix. A collimated detector (HPGe--20% relative efficiency) placed at 30 cm from the drum was used. The detection limit for sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co is approximately 45 Bq/kg for a sample of about 400 kg and a counting time of 10 min. A total measurement uncertainty of -70% to +40% was estimated.

  2. Ray-based calibration for the micro optical metrology system

    Science.gov (United States)

    Yin, Yongkai; Wang, Meng; Li, Ameng; Liu, Xiaoli; Peng, Xiang

    2014-05-01

    Fringe projection 3D microscopy (FP-3DM) plays an important role in micro-machining and micro-fabrication. FP-3DM may be realized with quite different arrangements and principles, which make people confused to select an appropriate one for their specific application. This paper introduces the ray-based general imaging model to describe the FP-3DM, which has the potential to get a unified expression for different system arrangements. Meanwhile the dedicated calibration procedure is also presented to realize quantitative 3D imaging. The validity and accuracy of proposed calibration approach is demonstrated with experiments.

  3. An integrated calibration system for liquid argon calorimetry

    CERN Document Server

    Marschalkowski, E; Mense, T; Nürnberger, H A; Schäfer, U

    1999-01-01

    A novel technical solution for an integrated version of the pulse generator of a calibration system for liquid argon calorimeters is presented. It consists of a differential amplifier with automatic offset compensation, a current mirror and a switching logic. These components are integrated on an ASIC chip in CMOS technology. The technical realisation as well as results on the performance are presented. (author)

  4. 40 CFR 92.116 - Engine output measurement system calibrations.

    Science.gov (United States)

    2010-07-01

    ... manufacturer's data, actual measurement, or the value recorded from the previous calibration used for this... load-cell or transfer standard may be used to verify the in-use torque measurement system. (i) The... spaced torque values as indicated by the master load-cell for each in-use range used. (v) The in-use...

  5. Calibration of a Plastic Classification System with the Ccw Model

    International Nuclear Information System (INIS)

    Barcala Riveira, J. M.; Fernandez Marron, J. L.; Alberdi Primicia, J.; Navarrete Marin, J. J.; Oller Gonzalez, J. C.

    2003-01-01

    This document describes the calibration of a plastic Classification system with the Ccw model (Classification by Quantum's built with Wavelet Coefficients). The method is applied to spectra of plastics usually present in domestic wastes. Obtained results are showed. (Author) 16 refs

  6. Online Sensor Calibration Assessment in Nuclear Power Systems

    International Nuclear Information System (INIS)

    Coble, Jamie B.; Ramuhalli, Pradeep; Meyer, Ryan M.; Hashemian, Hash

    2013-01-01

    Safe, efficient, and economic operation of nuclear systems (nuclear power plants, fuel fabrication and storage, used fuel processing, etc.) relies on transmission of accurate and reliable measurements. During operation, sensors degrade due to age, environmental exposure, and maintenance interventions. Sensor degradation can affect the measured and transmitted signals, including sensor failure, signal drift, sensor response time, etc. Currently, periodic sensor recalibration is performed to avoid these problems. Sensor recalibration activities include both calibration assessment and adjustment (if necessary). In nuclear power plants, periodic recalibration of safety-related sensors is required by the plant technical specifications. Recalibration typically occurs during refueling outages (about every 18 to 24 months). Non-safety-related sensors also undergo recalibration, though not as frequently. However, this approach to maintaining sensor calibration and performance is time-consuming and expensive, leading to unnecessary maintenance, increased radiation exposure to maintenance personnel, and potential damage to sensors. Online monitoring (OLM) of sensor performance is a non-invasive approach to assess instrument calibration. OLM can mitigate many of the limitations of the current periodic recalibration practice by providing more frequent assessment of calibration and identifying those sensors that are operating outside of calibration tolerance limits without removing sensors or interrupting operation. This can support extended operating intervals for unfaulted sensors and target recalibration efforts to only degraded sensors

  7. Automatic Calibration and Reconstruction for Active Vision Systems

    CERN Document Server

    Zhang, Beiwei

    2012-01-01

    In this book, the design of two new planar patterns for camera calibration of intrinsic parameters is addressed and a line-based method for distortion correction is suggested. The dynamic calibration of structured light systems, which consist of a camera and a projector is also treated. Also, the 3D Euclidean reconstruction by using the image-to-world transformation is investigated. Lastly, linear calibration algorithms for the catadioptric camera are considered, and the homographic matrix and fundamental matrix are extensively studied. In these methods, analytic solutions are provided for the computational efficiency and redundancy in the data can be easily incorporated to improve reliability of the estimations. This volume will therefore prove valuable and practical tool for researchers and practioners working in image processing and computer vision and related subjects.

  8. Some characteristics of isotopic separation laser systems

    International Nuclear Information System (INIS)

    Pochon, E.

    1988-01-01

    The principle of Laser Isotope Separation (LIS) is simple and based on either selective electronic photoexcitation and photoionization of atomic vapor, or selective vibrational photoexcitation and photodissociation of molecules in the gas phase. These processes, respectively called SILVA (AVLIS) and SILMO (MLIS) in France, both use specific laser systems with wavelengths spanning from infrared to ultraviolet. This article describes briefly some of the characteristics of a SILVA laser system. Following a three-step process, a SILVA laser system is based on dye copper vapor lasers. The pulse dye lasers provide the tunable laser light and are optically pumped by copper vapor laser operating at high repetition rates. In order to meet plant laser system requirements, the main improvements under way relate to copper vapor laser devices the power capability, efficiency, reliability and lifetime of which have to be increased. 1 fig

  9. Single-point relative process using Laser-Doppler velocimetry for calibration of flow sensors at temperatures above 100 C

    International Nuclear Information System (INIS)

    March, J.F.

    1996-01-01

    Due to technical difficulties, the calibration of flow sensors of heat meters above 100 C cannot be performed by the gravimetric standard method. A novel method using a laser Doppler velocimeter (LDV) was therefore developed, based on the gravimetric method below 100 C and on Reynolds' similarity law. This method allows a turbine meter to be calibrated as a secondary flowrate standard with a relative uncertainty below 0,2% for temperatures of up to 180 C. (orig.) [de

  10. 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.

  11. Calibration of the ORNL two-dimensional Thomson scattering system

    International Nuclear Information System (INIS)

    Thomas, C.E. Jr.; Lazarus, E.A.; Kindsfather, R.R.; Murakami, M.; Stewart, K.A.

    1985-10-01

    A unified presentation of the calibrations needed for accurate calculation of electron temperature and density from Thomson scattering data for the Oak Ridge National Laboratory two-dimensional Thomson scattering system (SCATPAK II) is made. Techniques are described for measuring the range of wavelengths to which each channel is responsive. A statistical method for calibrating the gain of each channel in the system is given, and methods of checking for internal consistency and accuracy are presented. The relationship between the constants describing the relative light collection efficiency of each channel and plasma light-scattering theory is developed, methods for measuring the channel efficiencies and evaluating their accuracy are described, and the effect on these constants of bending fiber optics is discussed. The use of Rayleigh or Raman scattering for absolute efficiency (density) calibration, stray light measurement, and system efficiency evaluation is discussed; the relative merits of Rayleigh vs Raman scattering are presented; and the relationship among the Rayleigh/Raman calibrations, relative channel efficiency constants, and absolute efficiencies is developed

  12. 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.

  13. Determination of a brass alloy concentration composition using calibration-free laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Achouri, M.; Baba-Hamed, T.; Beldjilali, S. A., E-mail: sidahmed.beldjilali@univ-usto.dz; Belasri, A. [Université des Sciences et de la Technologie d’Oran Mohamed Boudiaf USTO-MB, LPPMCA (Algeria)

    2015-09-15

    Laser-induced breakdown spectroscopy (LIBS) is a technique that can provide qualitative and quantitative measurements of the characteristics of irradiated metals. In the present work, we have calculated the parameters of the plasma produced from a brass alloy sample under the action of a pulsed Nd: YAG laser operating at 1064 nm. The emission lines of copper atoms (Cu I), zinc atoms (Zn I), and lead atoms (Pb I), which are elements of a brass alloy composition, were used to investigate the parameters of the brass plasma. The spectral profiles of Cu, Zn, and Pb lines have been used to extract the electron temperature and density of the brass alloy plasma. The characteristics of Cu, Zn, and Pb were determined quantatively by the calibration-free LIBS (CF-LIBS) method considering for accurate analysis that the laser-induced ablated plasma is optically thin in local thermodynamic equilibrium conditions and the plasma ablation is stoichiometric. The Boltzmann plot method was used to evaluate the plasma temperature, and the Stark broadened profiles were used to determine the electron density. An algorithm based on the experimentally measured values of the intensity of spectral lines and the basic laws of plasma physics was developed for the determination of Cu, Zn, and Pb concentrations in the brass sample. The concentrations C{sub CF-LIBS} calculated by CF-LIBS and the certified concentrations C{sub certified} were very close.

  14. Evaluation of a laser scanner for large volume coordinate metrology: a comparison of results before and after factory calibration

    International Nuclear Information System (INIS)

    Ferrucci, M; Muralikrishnan, B; Sawyer, D; Phillips, S; Petrov, P; Yakovlev, Y; Astrelin, A; Milligan, S; Palmateer, J

    2014-01-01

    Large volume laser scanners are increasingly being used for a variety of dimensional metrology applications. Methods to evaluate the performance of these scanners are still under development and there are currently no documentary standards available. This paper describes the results of extensive ranging and volumetric performance tests conducted on a large volume laser scanner. The results demonstrated small but clear systematic errors that are explained in the context of a geometric error model for the instrument. The instrument was subsequently returned to the manufacturer for factory calibration. The ranging and volumetric tests were performed again and the results are compared against those obtained prior to the factory calibration. (paper)

  15. The Dark Energy Survey Data Processing and Calibration System

    Energy Technology Data Exchange (ETDEWEB)

    Mohr, Joseph J. [Munich U.; Armstrong, Robert [Penn State U.; Bertin, Emmanuel [Paris, Inst. Astrophys.; Daues, Gregory E. [NCSA, Urbana; Desai, Shantanu [Munich U.; Gower, Michelle [NCSA, Urbana; Gruendl, Robert [Illinois U., Urbana (main); Hanlon, William [Illinois U., Urbana (main); Kuropatkin, Nikolay [Fermilab; Lin, Huan [Fermilab; Marriner, John [Fermilab; Petravick, Don; Sevilla, Ignacio [Madrid, CIEMAT; Swanson, Molly [Harvard-Smithsonian Ctr. Astrophys.; Tomashek, Todd [NCSA, Urbana; Tucker, Douglas [Fermilab; Yanny, Brian [Fermilab

    2012-09-24

    The Dark Energy Survey (DES) is a 5000 deg2 grizY survey reaching characteristic photometric depths of 24th magnitude (10 sigma) and enabling accurate photometry and morphology of objects ten times fainter than in SDSS. Preparations for DES have included building a dedicated 3 deg2 CCD camera (DECam), upgrading the existing CTIO Blanco 4m telescope and developing a new high performance computing (HPC) enabled data management system (DESDM). The DESDM system will be used for processing, calibrating and serving the DES data. The total data volumes are high (~2PB), and so considerable effort has gone into designing an automated processing and quality control system. Special purpose image detrending and photometric calibration codes have been developed to meet the data quality requirements, while survey astrometric calibration, coaddition and cataloging rely on new extensions of the AstrOmatic codes which now include tools for PSF modeling, PSF homogenization, PSF corrected model fitting cataloging and joint model fitting across multiple input images. The DESDM system has been deployed on dedicated development clusters and HPC systems in the US and Germany. An extensive program of testing with small rapid turn-around and larger campaign simulated datasets has been carried out. The system has also been tested on large real datasets, including Blanco Cosmology Survey data from the Mosaic2 camera. In Fall 2012 the DESDM system will be used for DECam commissioning, and, thereafter, the system will go into full science operations.

  16. Method of calibrating a fluid-level measurement system

    Science.gov (United States)

    Woodard, Stanley E. (Inventor); Taylor, Bryant D. (Inventor)

    2010-01-01

    A method of calibrating a fluid-level measurement system is provided. A first response of the system is recorded when the system's sensor(s) is (are) not in contact with a fluid of interest. A second response of the system is recorded when the system's sensor(s) is (are) fully immersed in the fluid of interest. Using the first and second responses, a plurality of expected responses of the system's sensor(s) is (are) generated for a corresponding plurality of levels of immersion of the sensor(s) in the fluid of interest.

  17. The detector calibration system for the CUORE cryogenic bolometer array

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, Jeremy S., E-mail: jeremy.cushman@yale.edu [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Dally, Adam [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Davis, Christopher J. [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Ejzak, Larissa; Lenz, Daniel [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Lim, Kyungeun E. [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Heeger, Karsten M., E-mail: karsten.heeger@yale.edu [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Maruyama, Reina H. [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Nucciotti, Angelo [Dipartimento di Fisica, Università di Milano-Bicocca, Milano I-20126 (Italy); INFN – Sezione di Milano Bicocca, Milano I-20126 (Italy); Sangiorgio, Samuele [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Wise, Thomas [Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 (United States); Department of Physics, University of Wisconsin, Madison, WI 53706 (United States)

    2017-02-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of {sup 130}Te and other rare events. The CUORE detector consists of 988 TeO{sub 2} bolometers operated underground at 10 mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the CUORE bolometer array combined with the extensive shielding surrounding the detectors requires the placement of calibration sources within the array itself. The CUORE Detector Calibration System is designed to insert radioactive sources into and remove them from the cryostat while respecting the stringent heat load, radiopurity, and operational requirements of the experiment. This paper describes the design, commissioning, and performance of this novel source calibration deployment system for ultra-low-temperature environments.

  18. Laser-based agriculture system

    KAUST Repository

    Ooi, Boon S.

    2016-03-31

    A system and method are provided for indoor agriculture using at least one growth chamber illuminated by laser light. In an example embodiment of the agriculture system, a growth chamber is provided having one or more walls defining an interior portion of the growth chamber. The agriculture system may include a removable tray disposed within the interior portion of the growth chamber. The agriculture system also includes a light source, which may be disposed outside the growth chamber. The one or more walls may include at least one aperture. The light source is configured to illuminate at least a part of the interior portion of the growth chamber. In embodiments in which the light source is disposed outside the growth chamber, the light source is configured to transmit the laser light to the interior portion of the growth chamber via the at least one aperture.

  19. Laser-based agriculture system

    KAUST Repository

    Ooi, Boon S.; Wong, Aloysius Tze; Ng, Tien Khee

    2016-01-01

    A system and method are provided for indoor agriculture using at least one growth chamber illuminated by laser light. In an example embodiment of the agriculture system, a growth chamber is provided having one or more walls defining an interior portion of the growth chamber. The agriculture system may include a removable tray disposed within the interior portion of the growth chamber. The agriculture system also includes a light source, which may be disposed outside the growth chamber. The one or more walls may include at least one aperture. The light source is configured to illuminate at least a part of the interior portion of the growth chamber. In embodiments in which the light source is disposed outside the growth chamber, the light source is configured to transmit the laser light to the interior portion of the growth chamber via the at least one aperture.

  20. Low-level laser therapy equipment needs calibration before clinical use

    Science.gov (United States)

    Machado de Senna, André; Machado-de-sena, Rosa Maria; Facundes, Arseni Lázaro; Barros Nepomuceno, Patrícia; Sávya Florentino, Wanilza; Olegário de Araújo, Ronyere

    2018-04-01

    Many factors can influence the radiant power delivered by the low-level laser therapy (LLLT) equipment, such as its cleaning and condition, as well as the use of plastic films for protecting the laser or even its time of use. Radiant power is an important factor to consider because it affects the amount of energy delivered to the target tissue. The difference between real radiant power (RRP) and nominal radiant power (NRP) may interfere in the expected results, because the delivered energy is different from the desired energy. Purpose: The objective of this study was to compare the NRP with the RRP offered by LLLT devices under clinical conditions of use. Material and Methods: For data collection to this study, 61 LLLT devices used in private and public dental practices in the state of Tocantins, Brazil, were evaluated. Three consecutive power measurements were performed at one-minute intervals and then the average of the measured power was calculated. The RRP was compared to the NRP. Results: The equipment presented NRP from 30 to 500mW while RRP ranged from 17.3 to 107.0mW. Discussion and Conclusion: The mean power measured in clinical conditions of use of the laser equipment was different from the nominal power reported by the manufacturers of the devices (p<0,01). The RRP ranged between 12.92% and 107% of NRP. This fact is worrisome, since one of the most important parameters for the success of the treatment of an injury using LLLT is the energy (power x time) delivered. These findings reinforce the need of calibrating the equipment before each laser application in order to avoid failures in the therapeutic conduct.

  1. The System of the Calibration for Visibility Measurement Instrument Under the Atmospheric Aerosol Simulation Environment

    Directory of Open Access Journals (Sweden)

    Shu Zhifeng

    2016-01-01

    Full Text Available Visibility is one of the most important parameters for meteorological observation and numerical weather prediction (NWP.It is also an important factor in everyday life, mainly for surface and air traffic especially in the Aeronautical Meteorology. The visibility decides the taking off and landing of aircraft. If the airport visibility is lower than requirement for aircraft taking off stipulated by International Civil Aviation Administration, then the aircraft must be parked at the airport. So the accurate measurement of visibility is very important. Nowadays, many devices can be measured the visibility or meteorological optical range (MOR such as Scatterometers, Transmissometers and visibility lidar. But there is not effective way to verify the accuracy of these devices expect the artificial visual method. We have developed a visibility testing system that can be calibration and verification these devices. The system consists of laser transmitter, optical chopper, phase-locking amplifier, the moving optic receiving system, signal detection and data acquisition system, atmospheric aerosol simulation chamber. All of them were placed in the atmosphere aerosol simulation chamber with uniform aerosol concentration. The Continuous wave laser, wavelength 550nm, has been transmitted into the collimation system then the laser beam expanded into 40mm diameter for compressing the laser divergence angle before modulated by optical chopper. The expanding beam transmitting in the atmosphere aerosol cabin received by the optic receiving system moving in the 50m length precision guide with 100mm optical aperture. The data of laser signal has been acquired by phase-locking amplifier every 5 meter range. So the 10 data points can be detected in the 50 meters guide once. The slope of the fitting curve can be obtained by linear fitting these data using the least square method. The laser extinction coefficient was calculated from the slope using the Koschmieder

  2. The VISTA ZYJHKs photometric system: calibration from 2MASS

    Science.gov (United States)

    González-Fernández, C.; Hodgkin, S. T.; Irwin, M. J.; González-Solares, E.; Koposov, S. E.; Lewis, J. R.; Emerson, J. P.; Hewett, P. C.; Yoldaş, A. K.; Riello, M.

    2018-03-01

    In this paper, we describe the routine photometric calibration of data taken with the VISTA infrared camera (VIRCAM) instrument on the ESO Visible and Infrared Survey Telescope for Astronomy (VISTA) telescope. The broad-band ZYJHKs data are directly calibrated from Two Micron all Sky Survey (2MASS) point sources visible in every VISTA image. We present the empirical transformations between the 2MASS and VISTA, and Wide-Field Camera and VISTA, photometric systems for regions of low reddening. We investigate the long-term performance of VISTA+VIRCAM. An investigation of the dependence of the photometric calibration on interstellar reddening leads to these conclusions: (1) For all broad-band filters, a linear colour-dependent correction compensates the gross effects of reddening where E(B - V) < 5.0. (2) For Z and Y, there is a significantly larger scatter above E(B - V) = 5.0, and insufficient measurements to adequately constrain the relation beyond this value. (3) The JHKs filters can be corrected to a few per cent up to E(B - V) = 10.0. We analyse spatial systematics over month-long time-scales, both inter- and intradetector and show that these are present only at very low levels in VISTA. We monitor and remove residual detector-to-detector offsets. We compare the calibration of the main pipeline products: pawprints and tiles. We show how variable seeing and transparency affect the final calibration accuracy of VISTA tiles, and discuss a technique, grouting, for mitigating these effects. Comparison between repeated reference fields is used to demonstrate that the VISTA photometry is precise to better than ≃ 2 per cent for the YJHKs bands and 3 per cent for the Z bands. Finally, we present empirically determined offsets to transform VISTA magnitudes into a true Vega system.

  3. Measuring Systems for Thermometer Calibration in Low-Temperature Range

    Science.gov (United States)

    Szmyrka-Grzebyk, A.; Lipiński, L.; Manuszkiewicz, H.; Kowal, A.; Grykałowska, A.; Jancewicz, D.

    2011-12-01

    The national temperature standard for the low-temperature range between 13.8033 K and 273.16 K has been established in Poland at the Institute of Low Temperature and Structure Research (INTiBS). The standard consists of sealed cells for realization of six fixed points of the International Temperature Scale of 1990 (ITS-90) in the low-temperature range, an adiabatic cryostat and Isotech water and mercury triple-point baths, capsule standard resistance thermometers (CSPRT), and AC and DC bridges with standard resistors for thermometers resistance measurements. INTiBS calibrates CSPRTs at the low-temperature fixed points with uncertainties less than 1 mK. In lower temperature range—between 2.5 K and about 25 K — rhodium-iron (RhFe) resistance thermometers are calibrated by comparison with a standard which participated in the EURAMET.T-K1.1 comparison. INTiBS offers a calibration service for industrial platinum resistance thermometers and for digital thermometers between 77 K and 273 K. These types of thermometers may be calibrated at INTiBS also in a higher temperature range up to 550°C. The Laboratory of Temperature Standard at INTiBS acquired an accreditation from the Polish Centre for Accreditation. A management system according to EN ISO/IEC 17025:2005 was established at the Laboratory and presented on EURAMET QSM Forum.

  4. Calibration-free quantitative analysis of elemental ratios in intermetallic nanoalloys and nanocomposites using Laser Induced Breakdown Spectroscopy (LIBS).

    Science.gov (United States)

    Davari, Seyyed Ali; Hu, Sheng; Mukherjee, Dibyendu

    2017-03-01

    Intermetallic nanoalloys (NAs) and nanocomposites (NCs) have increasingly gained prominence as efficient catalytic materials in electrochemical energy conversion and storage systems. But their morphology and chemical compositions play critical role in tuning their catalytic activities, and precious metal contents. While advanced microscopy techniques facilitate morphological characterizations, traditional chemical characterizations are either qualitative or extremely involved. In this study, we apply Laser Induced Breakdown Spectroscopy (LIBS) for quantitative compositional analysis of NAs and NCs synthesized with varied elemental ratios by our in-house built pulsed laser ablation technique. Specifically, elemental ratios of binary PtNi, PdCo (NAs) and PtCo (NCs) of different compositions are determined from LIBS measurements employing an internal calibration scheme using the bulk matrix species as internal standards. Morphology and qualitative elemental compositions of the aforesaid NAs and NCs are confirmed from Transmission Electron Microscopy (TEM) images and Energy Dispersive X-ray Spectroscopy (EDX) measurements. LIBS experiments are carried out in ambient conditions with the NA and NC samples drop cast on silicon wafers after centrifugation to increase their concentrations. The technique does not call for cumbersome sample preparations including acid digestions and external calibration standards commonly required in Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) techniques. Yet the quantitative LIBS results are in good agreement with the results from ICP-OES measurements. Our results indicate the feasibility of using LIBS in future for rapid and in-situ quantitative chemical characterizations of wide classes of synthesized NAs and NCs. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Calibration-Free Laser-Induced Breakdown Spectroscopy: State of the art

    Science.gov (United States)

    Tognoni, E.; Cristoforetti, G.; Legnaioli, S.; Palleschi, V.

    2010-01-01

    The aim of this paper is offering a critical review of Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS), the approach of multi-elemental quantitative analysis of LIBS spectra, based on the measurement of line intensities and plasma properties (plasma electron density and temperature) and on the assumption of a Boltzmann population of excited levels, which does not require the use of calibration curves or matrix-matched standards. The first part of this review focuses on the applications of the CF-LIBS method. Quantitative results reported in the literature, obtained in the analysis of various materials and in a wide range of experimental conditions, are summarized, with a special emphasis on the departure from nominal composition values. The second part is a discussion of the simplifying assumptions which lie at the basis of the CF-LIBS algorithm (stoichiometric ablation and complete atomization, thermal equilibrium, homogeneous plasma, thin radiation, detection of all elements). The inspection of the literature suggests that the CF-LIBS method is more accurate in analyzing metallic alloys rather than dielectrics. However, the full exploitation of the method seems to be still far to come, especially for the lack of a complete characterization of the effects of experimental constraints. However, some general directions can be suggested to help the analyst in designing LIBS measurements in a way which is more suited for CF-LIBS analysis.

  6. Calibrated Full-Waveform Airborne Laser Scanning for 3D Object Segmentation

    Directory of Open Access Journals (Sweden)

    Fanar M. Abed

    2014-05-01

    Full Text Available Segmentation of urban features is considered a major research challenge in the fields of photogrammetry and remote sensing. However, the dense datasets now readily available through airborne laser scanning (ALS offer increased potential for 3D object segmentation. Such potential is further augmented by the availability of full-waveform (FWF ALS data. FWF ALS has demonstrated enhanced performance in segmentation and classification through the additional physical observables which can be provided alongside standard geometric information. However, use of FWF information is not recommended without prior radiometric calibration, taking into account all parameters affecting the backscatter energy. This paper reports the implementation of a radiometric calibration workflow for FWF ALS data, and demonstrates how the resultant FWF information can be used to improve segmentation of an urban area. The developed segmentation algorithm presents a novel approach which uses the calibrated backscatter cross-section as a weighting function to estimate the segmentation similarity measure. The normal vector and the local Euclidian distance are used as criteria to segment the point clouds through a region growing approach. The paper demonstrates the potential to enhance 3D object segmentation in urban areas by integrating the FWF physical backscattered energy alongside geometric information. The method is demonstrated through application to an interest area sampled from a relatively dense FWF ALS dataset. The results are assessed through comparison to those delivered from utilising only geometric information. Validation against a manual segmentation demonstrates a successful automatic implementation, achieving a segmentation accuracy of 82%, and out-performs a purely geometric approach.

  7. Laser systems for on-line laser ion sources

    International Nuclear Information System (INIS)

    Geppert, Christopher

    2008-01-01

    Since its initiation in the middle of the 1980s, the resonant ionization laser ion source has been established as a reliable and efficient on-line ion source for radioactive ion beams. In comparison to other on-line ion sources it comprises the advantages of high versatility for the elements to be ionized and of high selectivity and purity for the ion beam generated by resonant laser radiation. Dye laser systems have been the predominant and pioneering working horses for laser ion source applications up to recently, but the development of all-solid-state titanium:sapphire laser systems has nowadays initiated a significant evolution within this field. In this paper an overview of the ongoing developments will be given, which have contributed to the establishment of a number of new laser ion source facilities worldwide during the last five years.

  8. Design and Calibration of an RF Actuator for Low-Level RF Systems

    Science.gov (United States)

    Geng, Zheqiao; Hong, Bo

    2016-02-01

    X-ray free electron laser (FEL) machines like the Linac Coherent Light Source (LCLS) at SLAC require high-quality electron beams to generate X-ray lasers for various experiments. Digital low-level RF (LLRF) systems are widely used to control the high-power RF klystrons to provide a highly stable RF field in accelerator structures for beam acceleration. Feedback and feedforward controllers are implemented in LLRF systems to stabilize or adjust the phase and amplitude of the RF field. To achieve the RF stability and the accuracy of the phase and amplitude adjustment, low-noise and highly linear RF actuators are required. Aiming for the upgrade of the S-band Linac at SLAC, an RF actuator is designed with an I/Qmodulator driven by two digital-to-analog converters (DAC) for the digital LLRF systems. A direct upconversion scheme is selected for RF actuation, and an on-line calibration algorithm is developed to compensate the RF reference leakage and the imbalance errors in the I/Q modulator, which may cause significant phase and amplitude actuation errors. This paper presents the requirements on the RF actuator, the design of the hardware, the calibration algorithm, and the implementation in firmware and software and the test results at LCLS.

  9. Generation of CsI cluster ions for mass calibration in matrix-assisted laser desorption/ionization mass spectrometry

    NARCIS (Netherlands)

    Lou, X.; Dongen, van J.L.J.; Meijer, E.W.

    2010-01-01

    A simple method was developed for the generation of cesium iodide (CsI) cluster ions up to m/z over 20,000 in matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). Calibration ions in both positive and negative ion modes can readily be generated from a single MALDI spot of CsI(3)

  10. A calibration-free ammonia breath sensor using a quantum cascade laser with WMS 2f/1f

    KAUST Repository

    Owen, Kyle; Farooq, Aamir

    2013-01-01

    modulation spectroscopy with second harmonic normalized by the first harmonic (WMS 2f/1f) is a sensitive technique used in the development of calibration-free sensors. An ammonia gas sensor is designed and developed that uses a quantum cascade laser operating

  11. High speed laser tomography system

    Science.gov (United States)

    Samsonov, D.; Elsaesser, A.; Edwards, A.; Thomas, H. M.; Morfill, G. E.

    2008-03-01

    A high speed laser tomography system was developed capable of acquiring three-dimensional (3D) images of optically thin clouds of moving micron-sized particles. It operates by parallel-shifting an illuminating laser sheet with a pair of galvanometer-driven mirrors and synchronously recording two-dimensional (2D) images of thin slices of the imaged volume. The maximum scanning speed achieved was 120000slices/s, sequences of 24 volume scans (up to 256 slices each) have been obtained. The 2D slices were stacked to form 3D images of the volume, then the positions of the particles were identified and followed in the consecutive scans. The system was used to image a complex plasma with particles moving at speeds up to cm/s.

  12. Development of a Calibration Strip for Immunochromatographic Assay Detection Systems.

    Science.gov (United States)

    Gao, Yue-Ming; Wei, Jian-Chong; Mak, Peng-Un; Vai, Mang-I; Du, Min; Pun, Sio-Hang

    2016-06-29

    With many benefits and applications, immunochromatographic (ICG) assay detection systems have been reported on a great deal. However, the existing research mainly focuses on increasing the dynamic detection range or application fields. Calibration of the detection system, which has a great influence on the detection accuracy, has not been addressed properly. In this context, this work develops a calibration strip for ICG assay photoelectric detection systems. An image of the test strip is captured by an image acquisition device, followed by performing a fuzzy c-means (FCM) clustering algorithm and maximin-distance algorithm for image segmentation. Additionally, experiments are conducted to find the best characteristic quantity. By analyzing the linear coefficient, an average value of hue (H) at 14 min is chosen as the characteristic quantity and the empirical formula between H and optical density (OD) value is established. Therefore, H, saturation (S), and value (V) are calculated by a number of selected OD values. Then, H, S, and V values are transferred to the RGB color space and a high-resolution printer is used to print the strip images on cellulose nitrate membranes. Finally, verification of the printed calibration strips is conducted by analyzing the linear correlation between OD and the spectral reflectance, which shows a good linear correlation (R² = 98.78%).

  13. Calibration of Water Supply Systems Based on Ant Colony Optimization

    Directory of Open Access Journals (Sweden)

    Mahmoud Faghfoor Maghrebi

    2013-03-01

    Full Text Available Leakage is one of the main problems in the water supply systems and due to the limitations in water supply and its costly process, reduction of leak in water distribution networks can be considered as one of the main goals of the water supply authorities. One of the leak detection techniques in water distribution system is the usage of the recorded node pressures at some locations to calibrate the whole system node pressures. Calibration process is accomplished by the optimization of a constrained objective function. Therefore, in addition to performing a hydraulic analysis of the network, application of an optimization technique is needed. In the current paper, a comparsion between the ant colony and genetic algorithm methodes, in calibration of the node pressures and leak detections was investigated. To examine the workability and the way of leak detection, analysis of the network with an assumed leak was carried out. The results showed that the effectiveness of the ant colony optimization in the detection of the position and magnitude of leak in a water network.

  14. Navigated Pattern Laser System versus Single-Spot Laser System for Postoperative 360-Degree Laser Retinopexy.

    Science.gov (United States)

    Kulikov, Alexei N; Maltsev, Dmitrii S; Boiko, Ernest V

    2016-01-01

    Purpose . To compare three 360°-laser retinopexy (LRP) approaches (using navigated pattern laser system, single-spot slit-lamp (SL) laser delivery, and single-spot indirect ophthalmoscope (IO) laser delivery) in regard to procedure duration, procedural pain score, technical difficulties, and the ability to achieve surgical goals. Material and Methods . Eighty-six rhegmatogenous retinal detachment patients (86 eyes) were included in this prospective randomized study. The mean procedural time, procedural pain score (using 4-point Verbal Rating Scale), number of laser burns, and achievement of the surgical goals were compared between three groups (pattern LRP (Navilas® laser system), 36 patients; SL-LRP, 28 patients; and IO-LRP, 22 patients). Results . In the pattern LRP group, the amount of time needed for LRP and pain level were statistically significantly lower, whereas the number of applied laser burns was higher compared to those in the SL-LRP group and in the IO-LRP group. In the pattern LRP, SL-LRP, and IO-LRP groups, surgical goals were fully achieved in 28 (77.8%), 17 (60.7%), and 13 patients (59.1%), respectively ( p > 0.05). Conclusion . The navigated pattern approach allows improving the treatment time and pain in postoperative 360° LRP. Moreover, 360° pattern LRP is at least as effective in achieving the surgical goal as the conventional (slit-lamp or indirect ophthalmoscope) approaches with a single-spot laser.

  15. Improvements of the ruby laser oscillator system for laser scattering

    International Nuclear Information System (INIS)

    Yamauchi, Toshihiko; Kumagai, Katsuaki; Kawakami, Tomohide; Matoba, Tohru; Funahashi, Akimasa

    1978-10-01

    A ruby laser oscillator system is used to measure electron temperatures of the Tokamak plasmas(JFT-2 and JFT-2a). Improvements have been made of the laser oscillator to obtain the correct values. Described are the improvements and the damages of a ruby rod and a KD*P crystal for Q-switching by laser beam. Improvement are the linear Xe lamp replaced by a helical Xe lamp and in the electrical circuit for Q-switching. The damage of an optical component by a laser beam should be clarified from the damage data; the cause is not found yet. (author)

  16. Improved spatial calibration for the CXRS system on EAST

    Energy Technology Data Exchange (ETDEWEB)

    Yin, X. H.; Feng, S. Y. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Li, Y. Y., E-mail: liyy@ipp.ac.cn; Fu, J.; Gu, Y. Q.; Cheng, Y.; Wan, B. N. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Jiang, D. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); School of Physics and Materials Science, Anhui University, Hefei 230601 (China); Lyu, B. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Hefei Science Center, Chinese Academy of Sciences, Hefei 230031 (China); Shi, Y. J. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Department of Nuclear Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Ye, M. Y. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China)

    2016-11-15

    A Charge eXchange Recombination Spectroscopy (CXRS) diagnostic system has been developed to measure profiles of ion temperature and rotation since 2014 on EAST. Several techniques have been developed to improve the spatial calibration of the CXRS diagnostic. The sightline location was obtained by measuring the coordinates of three points on each sightline using an articulated flexible coordinate measuring arm when the vessel was accessible. After vacuum pumping, the effect of pressure change in the vacuum vessel was evaluated by observing the movement of the light spot from back-illuminated sightlines on the first wall using the newly developed articulated inspection arm. In addition, the rotation of the periscope after vacuum pumping was derived by using the Doppler shift of neutral beam emission spectra without magnetic field. Combining these techniques, improved spatial calibration was implemented to provide a complete and accurate description of the EAST CXRS system. Due to the effects of the change of air pressure, a ∼0.4° periscope rotation, yielding a ∼20 mm movement of the major radius of observation positions to the lower field side, was derived. Results of Zeeman splitting of neutral beam emission spectra with magnetic field also showed good agreement with the calibration results.

  17. Calibration of a Microwave Imaging System Using a Known Scatterer

    DEFF Research Database (Denmark)

    Rubæk, Tonny; Zhurbenko, Vitaliy

    2010-01-01

    the transmission and receiving channels inside of the transceiver modules has been detected. This is most likely caused by the lessthan- perfect isolation of the switches in the modules as well as leakage through the PCB itself. Since the presence of such a leakage signal in the measurements seriously influence...... that the low-amplitude RF signals, available at the terminals of the antennas, only need to travel a very short distance to get to the low-noise amplifier, while the RF as well as the IF signals running to and from the transceiver modules all have significant amplitudes. However, some leakage between...... the imaging capability of the system, it is of interest to remove it. In this work, a calibration procedure capable of removing a constant offset, i.e., the leakage, from the measured signals is presented. The calibration procedure is based on a comparison between the relative change observed between...

  18. Design and development of an ultrasound calibration phantom and system

    Science.gov (United States)

    Cheng, Alexis; Ackerman, Martin K.; Chirikjian, Gregory S.; Boctor, Emad M.

    2014-03-01

    Image-guided surgery systems are often used to provide surgeons with informational support. Due to several unique advantages such as ease of use, real-time image acquisition, and no ionizing radiation, ultrasound is a common medical imaging modality used in image-guided surgery systems. To perform advanced forms of guidance with ultrasound, such as virtual image overlays or automated robotic actuation, an ultrasound calibration process must be performed. This process recovers the rigid body transformation between a tracked marker attached to the ultrasound transducer and the ultrasound image. A phantom or model with known geometry is also required. In this work, we design and test an ultrasound calibration phantom and software. The two main considerations in this work are utilizing our knowledge of ultrasound physics to design the phantom and delivering an easy to use calibration process to the user. We explore the use of a three-dimensional printer to create the phantom in its entirety without need for user assembly. We have also developed software to automatically segment the three-dimensional printed rods from the ultrasound image by leveraging knowledge about the shape and scale of the phantom. In this work, we present preliminary results from using this phantom to perform ultrasound calibration. To test the efficacy of our method, we match the projection of the points segmented from the image to the known model and calculate a sum squared difference between each point for several combinations of motion generation and filtering methods. The best performing combination of motion and filtering techniques had an error of 1.56 mm and a standard deviation of 1.02 mm.

  19. The calibration system of the GERDA muon veto Cherenkov detector

    International Nuclear Information System (INIS)

    Ritter, Florian; Lubsandorzhiev, Bayarto; Freund, Kai; Grabmayr, Peter; Jochum, Josef; Knapp, Markus; Meierhofer, Georg; Shaibonov, Bator

    2010-01-01

    The GERDA experiment searches for neutrinoless double beta decay (0νββ). To achieve a sensitivity of 10 -3 counts/(keVkgy) or better within a specific region of interest (ROI), a good background identification is needed. Therefore GERDA is located in the LNGS (Laboratori Nationali del Gran Sasso) underground facility. In addition to the good rejection of cosmic muons due to the surrounding bedrocks, a dual muon veto system has to be used. For calibration and monitoring of the muon veto, two separate systems have been developed.

  20. Calibration of the CCD photonic measuring system for railway inspection

    Science.gov (United States)

    Popov, D. V.; Ryabichenko, R. B.; Krivosheina, E. A.

    2005-08-01

    Increasing of traffic speed is the most important task in Moscow Metro. Requirements for traffic safety grow up simultaneously with the speed increasing. Currently for track inspection in Moscow Metro is used track measurement car has built in 1954. The main drawbacks of this system are absence of automated data processing and low accuracy. Non-contact photonic measurement system (KSIR) is developed for solving this problem. New track inspection car will be built in several months. This car will use two different track inspection systems and car locating subsystem based on track circuit counting. The KSIR consists of four subsystems: rail wear, height and track gauge measurement (BFSM); rail slump measurement (FIP); contact rail measurement (FKR); speed, level and car locating (USI). Currently new subsystem for wheel flange wear (IRK) is developed. The KSIR carry out measurements in real-time mode. The BFSM subsystem contains 4 matrix CCD cameras and 4 infrared stripe illuminators. The FIP subsystem contains 4 line CCD cameras and 4 spot illuminators. The FKR subsystem contains 2 matrix CCD cameras and 2 stripe illuminators. The IRK subsystem contains 2 CCD cameras and 2 stripe illuminators. Each system calibration was carried out for their adjustment. On the first step KSIR obtains data from photonic sensors which is valued in internal measurement units. Due to the calibration on the second step non-contact system converts the data to metric measurement system.

  1. The Upgraded Calibration System for the Scintillator-PMT Tile Hadronic Calorimeter of the ATLAS experiment at CERN/LHC

    CERN Document Server

    Chakraborty, Dhiman; The ATLAS collaboration

    2017-01-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy in highest energy proton-proton and heavy-ion collisions at CERN’s Large Hadron Collider. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs) located on the outside of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each read out by two PMTs in parallel. A multi-component calibration system is employed to calibrate and monitor the stability and performance of each part of the readout chain during data taking. The TileCal calibration system comprises Cesium radioactive sources, laser and charge injection elements and it allows to monitor and ...

  2. Calibration and Data Quality systems of the ATLAS Tile Calorimeter during the LHC Run-I operations

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00306374; The ATLAS collaboration

    2016-01-01

    The Tile Calorimeter is the hadronic calorimeter covering the central region of the ATLAS detector at the LHC. It consists of thin steel plates and scintillating tiles. Wavelength shifting fibres coupled to the tiles collect the produced light and are read out by photomultiplier tubes. The calibration scheme of the Tile Calorimeter comprises Cs radioactive source, laser and charge injection systems. Each stage of the signal production of the calorimeter from scintillation light to digitization is monitored and equalized. Description of the different TileCal calibration systems as well as the results on their performance in terms of calibration factors, linearity and stability are given. The data quality procedures and data quality efficiency of the Tile Calorimeter during the LHC data-taking period are presented as well.

  3. Calibration and Data Quality systems of the ATLAS Tile Calorimeter during the LHC Run-I operations

    CERN Document Server

    Zenis, Tibor; The ATLAS collaboration

    2015-01-01

    The Tile Calorimeter is the hadronic calorimeter covering the central region of the ATLAS detector at the LHC. It consists of thin steel plates and scintillating tiles. Wavelength shifting fibres coupled to the tiles collect the produced light and are read out by photomultiplier tubes. The calibration scheme of the Tile Calorimeter comprises Cs radioactive source, laser and charge injection systems. Each stage of the signal production of the calorimeter from scintillation light to digitization is monitored and equalized. Description of the different TileCal calibration systems as well as results on their performance in terms of calibration factors, linearity and stability will be given. The data quality procedures and data quality efficiency of the Tile Calorimeter during the LHC data-taking period are presented as well.

  4. The upgraded calibration system for the scintillator-PMT Tile Hadronic Calorimeter of the ATLAS experiment at CERN/LHC

    CERN Document Server

    Chakraborty, Dhiman; The ATLAS collaboration

    2017-01-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy in highest energy proton-proton and heavy-ion collisions at CERN’s Large Hadron Collider. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs) located on the outside of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each read out by two PMTs in parallel. A multi-component calibration system is employed to calibrate and monitor the stability and performance of each part of the readout chain during data taking. The TileCal calibration system comprises Cesium radioactive sources, laser and charge injection elements and it allows to monitor and ...

  5. CO laser angioplasty system: efficacy of manipulatable laser angioscope catheter

    Science.gov (United States)

    Arai, Tsunenori; Kikuchi, Makoto; Mizuno, Kyoichi; Sakurada, Masami; Miyamoto, Akira; Arakawa, Koh; Kurita, Akira; Nakamura, Haruo; Takeuchi, Kiyoshi; Utsumi, Atsushi; Akai, Yoshiro

    1992-08-01

    A percutaneous transluminal coronary angioplasty system using a unique combination of CO laser (5 micrometers ) and As-S infrared glass fiber under the guidance of a manipulatable laser angioscope catheter is described. The ablation and guidance functions of this system are evaluated. The angioplasty treatment procedure under angioscope guidance was studied by in vitro model experiment and in vivo animal experiment. The whole angioplasty system is newly developed. That is, a transportable compact medical CO laser device which can emit up to 10 W, a 5 F manipulatable laser angioscope catheter, a thin CO laser cable of which the diameter is 0.6 mm, an angioscope imaging system for laser ablation guidance, and a system controller were developed. Anesthetized adult mongrel dogs (n equals 5) with an artificial complete occlusion in the femoral artery and an artificial human vessel model including occluded or stenotic coronary artery were used. The manipulatability of the catheter was drastically improved (both rotation and bending), therefore, precise control of ablation to expand stenosis was obtained. A 90% artificial stenosis made of human yellow plaque in 4.0 mm diameter in the vessel was expanded to 70% stenosis by repetitive CO laser ablations of which total energy was 220 J. All procedures were performed and controlled under angioscope visualization.

  6. A Vision-Based Self-Calibration Method for Robotic Visual Inspection Systems

    Science.gov (United States)

    Yin, Shibin; Ren, Yongjie; Zhu, Jigui; Yang, Shourui; Ye, Shenghua

    2013-01-01

    A vision-based robot self-calibration method is proposed in this paper to evaluate the kinematic parameter errors of a robot using a visual sensor mounted on its end-effector. This approach could be performed in the industrial field without external, expensive apparatus or an elaborate setup. A robot Tool Center Point (TCP) is defined in the structural model of a line-structured laser sensor, and aligned to a reference point fixed in the robot workspace. A mathematical model is established to formulate the misalignment errors with kinematic parameter errors and TCP position errors. Based on the fixed point constraints, the kinematic parameter errors and TCP position errors are identified with an iterative algorithm. Compared to the conventional methods, this proposed method eliminates the need for a robot-based-frame and hand-to-eye calibrations, shortens the error propagation chain, and makes the calibration process more accurate and convenient. A validation experiment is performed on an ABB IRB2400 robot. An optimal configuration on the number and distribution of fixed points in the robot workspace is obtained based on the experimental results. Comparative experiments reveal that there is a significant improvement of the measuring accuracy of the robotic visual inspection system. PMID:24300597

  7. Laser spark distribution and ignition system

    Science.gov (United States)

    Woodruff, Steven [Morgantown, WV; McIntyre, Dustin L [Morgantown, WV

    2008-09-02

    A laser spark distribution and ignition system that reduces the high power optical requirements for use in a laser ignition and distribution system allowing for the use of optical fibers for delivering the low peak energy pumping pulses to a laser amplifier or laser oscillator. An optical distributor distributes and delivers optical pumping energy from an optical pumping source to multiple combustion chambers incorporating laser oscillators or laser amplifiers for inducing a laser spark within a combustion chamber. The optical distributor preferably includes a single rotating mirror or lens which deflects the optical pumping energy from the axis of rotation and into a plurality of distinct optical fibers each connected to a respective laser media or amplifier coupled to an associated combustion chamber. The laser spark generators preferably produce a high peak power laser spark, from a single low power pulse. The laser spark distribution and ignition system has application in natural gas fueled reciprocating engines, turbine combustors, explosives and laser induced breakdown spectroscopy diagnostic sensors.

  8. Fission fragment excited laser system

    Science.gov (United States)

    McArthur, David A.; Tollefsrud, Philip B.

    1976-01-01

    A laser system and method for exciting lasing action in a molecular gas lasing medium which includes cooling the lasing medium to a temperature below about 150 K and injecting fission fragments through the lasing medium so as to preferentially excite low lying vibrational levels of the medium and to cause population inversions therein. The cooled gas lasing medium should have a mass areal density of about 5 .times. 10.sup.-.sup.3 grams/square centimeter, relaxation times of greater than 50 microseconds, and a broad range of excitable vibrational levels which are excitable by molecular collisions.

  9. Calibration of a spectrometry multisphere system for neutron fields

    International Nuclear Information System (INIS)

    Carelli, Jorge L.; Cruzate, Juan A.; Papadopulos, Susana B.; Gregori, Beatriz N.; Ciocci Brazzano, Ligia

    2005-01-01

    In this work it is presented the calibration of the neutrons spectrometric system of the Nuclear Regulatory Authority (ARN) in the Institut de Protection et Sure te Nucleaires (Ipn), Labourite dadaist et de Recherche s en Dosimetric Extern e, Cadarache, France. The multisphere system is composed of 9 polyethylene spheres of high density, with a gaseous detector of 3 He and associate electronics. The matrix of energy response to the system neutrons was obtained applying the MCNPX code for the range of energies between thermal and 100 MeV with cross sections taken from library ENDF/B-VI. The neutron spectra of the multisphere system were obtained applying the deconvolution code LOUHI82. The relationship between the theoretical responses and the experiences obtained with the AmBe and 252 Cf sources are also presented in this work [es

  10. Short pulse laser systems for biomedical applications

    CERN Document Server

    Mitra, Kunal

    2017-01-01

    This book presents practical information on the clinical applications of short pulse laser systems and the techniques for optimizing these applications in a manner that will be relevant to a broad audience, including engineering and medical students as well as researchers, clinicians, and technicians. Short pulse laser systems are useful for both subsurface tissue imaging and laser induced thermal therapy (LITT), which hold great promise in cancer diagnostics and treatment. Such laser systems may be used alone or in combination with optically active nanoparticles specifically administered to the tissues of interest for enhanced contrast in imaging and precise heating during LITT. Mathematical and computational models of short pulse laser-tissue interactions that consider the transient radiative transport equation coupled with a bio-heat equation considering the initial transients of laser heating were developed to analyze the laser-tissue interaction during imaging and therapy. Experiments were first performe...

  11. Calibration of PIXE-SP system of elementary analysis

    International Nuclear Information System (INIS)

    Tabacniks, M.H.

    1983-04-01

    The set-up and calibration of the PIXE-SP System of Elementary Analysis located at the Institute of Physics of the University of Sao Paulo is described. The PIXE-SP, that operates with 8 MeV alpha beam, has been calibrated for elements with Z >= 11, by means of homemade evaporated standard targets of Al, Si, Bacl 2 , K 2 CrO 4 , Ti, Cr, Mn, Fe, Cu, Ge, Ag, Sn, and Au. Those targets are thin, homogeneous, and have been calbrated on a microbalance within an average precision of 6%. The overall precision of the PIXE-SP System is estimated in 10% for elements with 16 2 thick, irradiated with a 10 μC electric charge, shows a minimum of about 0,1 ng (approximated 4 ppm) for Mn. The PIXE-SP System has also been intercalibrated with the PIXE located at University of Gent, Belgium, by means of 12 atmospheric aerosol targets collected on two Batelle Cascade Impactors. The analyzed masses of elements with 16 [pt

  12. Laser and photonic systems design and integration

    CERN Document Server

    Nof, Shimon Y; Cheng, Gary J

    2014-01-01

    New, significant scientific discoveries in laser and photonic technologies, systems perspectives, and integrated design approaches can improve even further the impact in critical areas of challenge. Yet this knowledge is dispersed across several disciplines and research arenas. Laser and Photonic Systems: Design and Integration brings together a multidisciplinary group of experts to increase understanding of the ways in which systems perspectives may influence laser and photonic innovations and application integration.By bringing together chapters from leading scientists and technologists, ind

  13. Multiplex electric discharge gas laser system

    Science.gov (United States)

    Laudenslager, James B. (Inventor); Pacala, Thomas J. (Inventor)

    1987-01-01

    A multiple pulse electric discharge gas laser system is described in which a plurality of pulsed electric discharge gas lasers are supported in a common housing. Each laser is supplied with excitation pulses from a separate power supply. A controller, which may be a microprocessor, is connected to each power supply for controlling the application of excitation pulses to each laser so that the lasers can be fired simultaneously or in any desired sequence. The output light beams from the individual lasers may be combined or utilized independently, depending on the desired application. The individual lasers may include multiple pairs of discharge electrodes with a separate power supply connected across each electrode pair so that multiple light output beams can be generated from a single laser tube and combined or utilized separately.

  14. Extrinsic Calibration for Vehicle-based Mobile Mapping System

    Directory of Open Access Journals (Sweden)

    SHI Limei

    2015-01-01

    Full Text Available Having the advantage of 360° imaging and rotation invariance, panoramic camera has gradually been used in mobile mapping systems(MMS. Calibration is an essential requirement to make sure that MMS can get high quality geo-information. This paper presents a way to address the extrinsic calibration for vehicle-based MMS composed of panoramic camera and Position and Orientation System (POS. Firstly, control points in the natural scene are set up, whose spatial coordinates are measured with high precision. Secondly, a panoramic spherical model is constructed and panoramic image can be projected to this model by means of spherical reverse transformation projection. Then, localize and select the control points in 3D spherical panoramic view but not in panoramic distorted image directly, the spherical coordinates of control points in panoramic image are gotten. After points correspondence is established, make use of direct geo-reference positioning equation and coordinate transformation, the translation and rotation parameters of panoramic camera relative to POS are computed. Experiments are conducted separately in space city calibration site located in Beijing and the Binhai New Area in Tianjin using our approach. Test results are listed as follows. When the GPS signal are of good quality, absolute positioning mean square error of a point is 10.3 cm in two-dimension plane and 16.5 cm in height direction; Otherwise, it is 35.4 cm in two-dimension plane and 54.8 cm in height direction. The max relative error of distance measurement is about 5 cm over a short distance (distance<3 km, which is not obviously affected by the GPS signal quality.

  15. Geometrical effects in data collection and processing for calibration-free laser-induced breakdown spectroscopy

    Science.gov (United States)

    Shabanov, S. V.; Gornushkin, I. B.

    2018-01-01

    Data processing in the calibration-free laser-induced breakdown spectroscopy (LIBS) is usually based on the solution of the radiative transfer equation along a particular line of sight through a plasma plume. The LIBS data processing is generalized to the case when the spectral data are collected from large portions of the plume. It is shown that by adjusting the optical depth and width of the lines the spectra obtained by collecting light from an entire spherical homogeneous plasma plume can be least-square fitted to a spectrum obtained by collecting the radiation just along a plume diameter with a relative error of 10-11 or smaller (for the optical depth not exceeding 0.3) so that a mismatch of geometries of data processing and data collection cannot be detected by fitting. Despite the existence of such a perfect least-square fit, the errors in the line optical depth and width found by a data processing with an inappropriate geometry can be large. It is shown with analytic and numerical examples that the corresponding relative errors in the found elemental number densities and concentrations may be as high as 50% and 20%, respectively. Safe for a few found exceptions, these errors are impossible to eliminate from LIBS data processing unless a proper solution of the radiative transfer equation corresponding to the ray tracing in the spectral data collection is used.

  16. Materials for spaceborne laser systems

    International Nuclear Information System (INIS)

    Gusarov, A.

    2006-01-01

    Advanced laser systems are attracting a growing interest for space missions, in particular for LIDAR (LIght Detection And Ranging) applications. An important issue for the LIDARs is the very strict requirements on the optical performance and more specifically the need for a high optical output power combined with a nearly perfect output beam quality. These features are traditionally in conflict with each other. Thermally induced phase distortions indeed corrupt the beam quality of high-power solid-state lasers and it becomes increasingly difficult to maintain a good beam quality while increasing the output power. A possible solution of the problem is to use the optical phase conjugation, which provides a method to dynamically correct for those aberrations. A process by which phase-conjugated waves can be generated is the SBS (stimulated Brillouin scattering). SBS mirrors commonly used in terrestrial application are based on liquids or gases, which are not 'space-friendly' and often toxic. The solid-state alternative seems the most appropriate for space. Such PCMs (Phase-Conjugating Mirrors) have been the subject of many research efforts in recent years and a significant progress in improving their characteristics has been achieved. However, the issue of space qualification remains open. To address it, the European Space Agency initiated in 2004 the research project named Solid-State Phase Conjugation, Radiation Testing and Evaluation for Core Laser Technologies with the TRT (Thales Research and Technology), France, as the prime contractor, and the CSL (Centre Spatial de Liege) and SCKCEN as the subcontractors. The project is to be completed in 2006. To qualify a PCM for a spaceborne laser system, one has to address a number of specific issues. Such a component must be mechanically rugged to sustain vibrations during the launch phase, provide a low out-gassing to prevent optical surfaces contamination in vacuum, be highly reliable to operate properly without

  17. Calibrating a novel multi-sensor physical activity measurement system

    International Nuclear Information System (INIS)

    John, D; Sasaki, J E; Howe, C A; Freedson, P S; Liu, S; Gao, R X; Staudenmayer, J

    2011-01-01

    Advancing the field of physical activity (PA) monitoring requires the development of innovative multi-sensor measurement systems that are feasible in the free-living environment. The use of novel analytical techniques to combine and process these multiple sensor signals is equally important. This paper describes a novel multi-sensor 'integrated PA measurement system' (IMS), the lab-based methodology used to calibrate the IMS, techniques used to predict multiple variables from the sensor signals, and proposes design changes to improve the feasibility of deploying the IMS in the free-living environment. The IMS consists of hip and wrist acceleration sensors, two piezoelectric respiration sensors on the torso, and an ultraviolet radiation sensor to obtain contextual information (indoors versus outdoors) of PA. During lab-based calibration of the IMS, data were collected on participants performing a PA routine consisting of seven different ambulatory and free-living activities while wearing a portable metabolic unit (criterion measure) and the IMS. Data analyses on the first 50 adult participants are presented. These analyses were used to determine if the IMS can be used to predict the variables of interest. Finally, physical modifications for the IMS that could enhance the feasibility of free-living use are proposed and refinement of the prediction techniques is discussed

  18. Evolution of the JPSS Ground Project Calibration and Validation System

    Science.gov (United States)

    Purcell, Patrick; Chander, Gyanesh; Jain, Peyush

    2016-01-01

    The Joint Polar Satellite System (JPSS) is the National Oceanic and Atmospheric Administration's (NOAA) next-generation operational Earth observation Program that acquires and distributes global environmental data from multiple polar-orbiting satellites. The JPSS Program plays a critical role to NOAA's mission to understand and predict changes in weather, climate, oceans, coasts, and space environments, which supports the Nation's economy and protection of lives and property. The National Aeronautics and Space Administration (NASA) is acquiring and implementing the JPSS, comprised of flight and ground systems, on behalf of NOAA. The JPSS satellites are planned to fly in the afternoon orbit and will provide operational continuity of satellite-based observations and products for NOAA Polar-orbiting Operational Environmental Satellites (POES) and the Suomi National Polar-orbiting Partnership (SNPP) satellite. To support the JPSS Calibration and Validation (CalVal) node Government Resource for Algorithm Verification, Independent Test, and Evaluation (GRAVITE) services facilitate: Algorithm Integration and Checkout, Algorithm and Product Operational Tuning, Instrument Calibration, Product Validation, Algorithm Investigation, and Data Quality Support and Monitoring. GRAVITE is a mature, deployed system that currently supports the SNPP Mission and has been in operations since SNPP launch. This paper discusses the major re-architecture for Block 2.0 that incorporates SNPP lessons learned, architecture of the system, and demonstrates how GRAVITE has evolved as a system with increased performance. It is now a robust, stable, reliable, maintainable, scalable, and secure system that supports development, test, and production strings, replaces proprietary and custom software, uses open source software, and is compliant with NASA and NOAA standards.

  19. Surface characterization of weathered wood using a laser scanning system

    International Nuclear Information System (INIS)

    Arnold, M.; Lemaster, R.L.; Dost, W.A.

    1992-01-01

    Most of the existing methods to assess the effect of weathering on wood surfaces have some drawbacks that limit their use to specific tasks. The amount of surface erosion is often used as a measure for the weathering action. The application of a laser scanning system to reproduce surface profiles and to measure weathering erosion was tested on various samples and was found to be a very useful and superior alternative to existing methods. Further improvements of the system used can be made by refinements of the calibration procedures and by more comprehensive profile analyses. (author)

  20. Dynamically variable spot size laser system

    Science.gov (United States)

    Gradl, Paul R. (Inventor); Hurst, John F. (Inventor); Middleton, James R. (Inventor)

    2012-01-01

    A Dynamically Variable Spot Size (DVSS) laser system for bonding metal components includes an elongated housing containing a light entry aperture coupled to a laser beam transmission cable and a light exit aperture. A plurality of lenses contained within the housing focus a laser beam from the light entry aperture through the light exit aperture. The lenses may be dynamically adjusted to vary the spot size of the laser. A plurality of interoperable safety devices, including a manually depressible interlock switch, an internal proximity sensor, a remotely operated potentiometer, a remotely activated toggle and a power supply interlock, prevent activation of the laser and DVSS laser system if each safety device does not provide a closed circuit. The remotely operated potentiometer also provides continuous variability in laser energy output.

  1. Standard Reference Line Combined with One-Point Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) to Quantitatively Analyze Stainless and Heat Resistant Steel.

    Science.gov (United States)

    Fu, Hongbo; Wang, Huadong; Jia, Junwei; Ni, Zhibo; Dong, Fengzhong

    2018-01-01

    Due to the influence of major elements' self-absorption, scarce observable spectral lines of trace elements, and relative efficiency correction of experimental system, accurate quantitative analysis with calibration-free laser-induced breakdown spectroscopy (CF-LIBS) is in fact not easy. In order to overcome these difficulties, standard reference line (SRL) combined with one-point calibration (OPC) is used to analyze six elements in three stainless-steel and five heat-resistant steel samples. The Stark broadening and Saha - Boltzmann plot of Fe are used to calculate the electron density and the plasma temperature, respectively. In the present work, we tested the original SRL method, the SRL with the OPC method, and intercept with the OPC method. The final calculation results show that the latter two methods can effectively improve the overall accuracy of quantitative analysis and the detection limits of trace elements.

  2. National Ignition Facility system design requirements Laser System SDR002

    International Nuclear Information System (INIS)

    Larson, D.W.; Bowers, J.M.; Bliss, E.S.; Karpenko, V.P.; English, E.

    1996-01-01

    This System Design Requirement document establishes the performance, design, development, and test requirements for the NIP Laser System. The Laser System generates and delivers high-power optical pulses to the target chamber, and is composed of all optical puke creating and transport elements from Puke Generation through Final Optics as well as the special equipment that supports, energizes and controls them. The Laser System consists of the following WBS elements: 1.3 Laser System 1.4 Beam Transport System 1.6 Optical Components 1.7 Laser Control 1.8.7 Final Optics

  3. Electronics and Calibration system for the CMS Beam Halo Monitor

    CERN Document Server

    Tosi, Nicolò; Fabbri, Franco L; Finkel, Alexey; Orfanelli, Stella; Loos, R; Montanari, Alessandro; Rusack, R; Stickland, David P

    2014-01-01

    In the context of increasing luminosity of LHC, it will be important to accurately measure the Machine Induced Background. A new monitoring system will be installed in the cavern of the Compact Muon Solenoid (CMS) experiment for measuring the beam background at high radius. This detector is composed of synthetic quartz Cherenkov radiators, coupled to fast photomultiplier tubes (PMT). The readout chain of this detector will make use of many components developed for the Phase 1 upgrade to the CMS Hadron Calorimeter electronics, with a dedicated firmware and readout adapted to the beam monitoring requirements. The PMT signal will be digitized by a charge integrating ASIC (QIE10), providing both the signal rise time and the charge integrated over one bunch crossing. The backend electronics will record bunch-by-bunch histograms, which will be published to CMS and the LHC using the newly designed CMS beam instrumentation specific DAQ. A calibration monitoring system has been designed to generate triggered pulses of...

  4. "Calibration" system for spectral measurements and its experimental results

    Science.gov (United States)

    Bruchkouskaya, Sviatlana I.; Katkovsky, Leonid V.; Belyaev, Boris I.; Malyshev, Vladislav B.

    2017-04-01

    "Calibration" system has been developed at A. N. Sevchenko Research Institute of Applied Physical Problems of the Belarusian State University. It was designed for measuring the characteristics of spectral reflectance of all types of natural surfaces (test sites) in ground conditions or on board of aircraft carriers and has the following components: - Photospectroradiometr (PhSR) of high resolution with a range of 400-900 nm, equipped with a digital time-lapse video system; - Two-channel modular spectroradiometer (TMS) with a range of 400-900 nm, designed for simultaneous measurements of reflected light brightness of the underlying surface and the incident radiation from the upper hemisphere; - Two portable spectroradiometers (PSR-700 and PSR-1300) with a spectral range 800-1500 nm; 1200-2500 nm; - Scanning solar spectropolarimeter (SSP-600) with a range of 350-950 nm for measurements of direct sunlight and scattered by the atmosphere at different angles; "Calibration" system provides spectral resolution of 5.2 nm in a range of 400-900 nm, 10 nm in a range of 800-1500 nm and 15 nm in a range of 1200-2500 nm. Measurements of the optical characteristics of solar radiation (for determining parameters of the atmosphere) and that of underlying surface are synchronous. There is also a set of special nozzles for measurements of spectral brightness coefficients, polarization characteristics and spectral albedo. Spectra and images are geotagged to the navigation data (time, GPS). For the measurements of spectral reflection dependencies within "Monitoring-SG" framework expeditions to the Kuril Islands, Kursk aerospace test site and Kamchatka Peninsula were conducted in 2015 and 2016. The spectra of different underlying surfaces have been obtained: soils, plants and water objects, sedimentary and volcanic rocks. These surveys are a valuable material for further researches and selection of test facilities for flight calibration of space imaging systems. Information obtained

  5. A Self-Calibrating Remote Control Chemical Monitoring System

    Energy Technology Data Exchange (ETDEWEB)

    Jessica Croft

    2007-06-01

    The Susie Mine, part of the Upper Tenmile Mining Area, is located in Rimini, MT about 15 miles southwest of Helena, MT. The Upper Tenmile Creek Mining Area is an EPA Superfund site with 70 abandoned hard rock mines and several residential yards prioritized for clean up. Water from the Susie mine flows into Tenmile Creek from which the city of Helena draws part of its water supply. MSE Technology Applications in Butte, Montana was contracted by the EPA to build a treatment system for the Susie mine effluent and demonstrate a system capable of treating mine waste water in remote locations. The Idaho National Lab was contracted to design, build and demonstrate a low maintenance self-calibrating monitoring system that would monitor multiple sample points, allow remote two-way communications with the control software and allow access to the collected data through a web site. The Automated Chemical Analysis Monitoring (ACAM) system was installed in December 2006. This thesis documents the overall design of the hardware, control software and website, the data collected while MSE-TA’s system was operational, the data collected after MSE-TA’s system was shut down and suggested improvements to the existing system.

  6. Guidelines for the Calibration of Routine Dosimetry Systems for use in Radiation Processing

    DEFF Research Database (Denmark)

    Sharpe, Peter; Miller, Arne

    A set of guidelines has been developed to assist in the calibration of routine dosimetry systems for use in industrial radiation processing plants. Topics covered include the calibration of equipment, the performance of calibration irradiations and the derivation of mathematical functions...

  7. High-performance OPCPA laser system

    International Nuclear Information System (INIS)

    Zuegel, J.D.; Bagnoud, V.; Bromage, J.; Begishev, I.A.; Puth, J.

    2006-01-01

    Optical parametric chirped-pulse amplification (OPCPA) is ideally suited for amplifying ultra-fast laser pulses since it provides broadband gain across a wide range of wavelengths without many of the disadvantages of regenerative amplification. A high-performance OPCPA system has been demonstrated as a prototype for the front end of the OMEGA Extended Performance (EP) Laser System. (authors)

  8. High-performance OPCPA laser system

    Energy Technology Data Exchange (ETDEWEB)

    Zuegel, J.D.; Bagnoud, V.; Bromage, J.; Begishev, I.A.; Puth, J. [Rochester Univ., Lab. for Laser Energetics, NY (United States)

    2006-06-15

    Optical parametric chirped-pulse amplification (OPCPA) is ideally suited for amplifying ultra-fast laser pulses since it provides broadband gain across a wide range of wavelengths without many of the disadvantages of regenerative amplification. A high-performance OPCPA system has been demonstrated as a prototype for the front end of the OMEGA Extended Performance (EP) Laser System. (authors)

  9. BENCHMARKING MOBILE LASER SCANNING SYSTEMS USING A PERMANENT TEST FIELD

    Directory of Open Access Journals (Sweden)

    H. Kaartinen

    2012-07-01

    Full Text Available The objective of the study was to benchmark the geometric accuracy of mobile laser scanning (MLS systems using a permanent test field under good coverage of GNSS. Mobile laser scanning, also called mobile terrestrial laser scanning, is currently a rapidly developing area in laser scanning where laser scanners, GNSS and IMU are mounted onboard a moving vehicle. MLS can be considered to fill the gap between airborne and terrestrial laser scanning. Data provided by MLS systems can be characterized with the following technical parameters: a point density in the range of 100-1000 points per m2 at 10 m distance, b distance measurement accuracy of 2-5 cm, and c operational scanning range from 1 to 100 m. Several commercial, including e.g. Riegl, Optech and others, and some research mobile laser scanning systems surveyed the test field using predefined driving speed and directions. The acquired georeferenced point clouds were delivered for analyzing. The geometric accuracy of the point clouds was determined using the reference targets that could be identified and measured from the point cloud. Results show that in good GNSS conditions most systems can reach an accuracy of 2 cm both in plane and elevation. The accuracy of a low cost system, the price of which is less than tenth of the other systems, seems to be within a few centimetres at least in ground elevation determination. Inaccuracies in the relative orientation of the instruments lead to systematic errors and when several scanners are used, in multiple reproductions of the objects. Mobile laser scanning systems can collect high density point cloud data with high accuracy. A permanent test field suits well for verifying and comparing the performance of different mobile laser scanning systems. The accuracy of the relative orientation between the mapping instruments needs more attention. For example, if the object is seen double in the point cloud due to imperfect boresight calibration between two

  10. Laser surveillance system for spent fuel

    International Nuclear Information System (INIS)

    Fiarman, S.; Zucker, M.S.; Bieber, A.M. Jr.

    1980-01-01

    A laser surveillance system installed at spent fuel storage pools (SFSP's) will provide the safeguard inspector with specific knowledge of spent fuel movement that cannot be obtained with current surveillance systems. The laser system will allow for the division of the pool's spent fuel inventory into two populations - those assemblies which have been moved and those which haven't - which is essential for maximizing the efficiency and effectiveness of the inspection effort. We have designed, constructed, and tested a full size laser system operating in air and have used an array of 6 zircaloy BWR tubes to simulate an assembly. The reflective signal from the zircaloy rods is a strong function of position of the assembly, but in all cases is easily discernable from the reference scan of the background with no assembly. A design for a SFSP laser surveillance system incorporating laser ranging is discussed. 10 figures

  11. The Theory of Random Laser Systems

    International Nuclear Information System (INIS)

    Xunya Jiang

    2002-01-01

    Studies of random laser systems are a new direction with promising potential applications and theoretical interest. The research is based on the theories of localization and laser physics. So far, the research shows that there are random lasing modes inside the systems which is quite different from the common laser systems. From the properties of the random lasing modes, they can understand the phenomena observed in the experiments, such as multi-peak and anisotropic spectrum, lasing mode number saturation, mode competition and dynamic processes, etc. To summarize, this dissertation has contributed the following in the study of random laser systems: (1) by comparing the Lamb theory with the Letokhov theory, the general formulas of the threshold length or gain of random laser systems were obtained; (2) they pointed out the vital weakness of previous time-independent methods in random laser research; (3) a new model which includes the FDTD method and the semi-classical laser theory. The solutions of this model provided an explanation of the experimental results of multi-peak and anisotropic emission spectra, predicted the saturation of lasing modes number and the length of localized lasing modes; (4) theoretical (Lamb theory) and numerical (FDTD and transfer-matrix calculation) studies of the origin of localized lasing modes in the random laser systems; and (5) proposal of using random lasing modes as a new path to study wave localization in random systems and prediction of the lasing threshold discontinuity at mobility edge

  12. Standard-target calibration of an acoustic backscatter system

    Science.gov (United States)

    Foote, Kenneth G.; Martini, Marinna A.

    2010-01-01

    The standard-target method used to calibrate scientific echo sounders and other scientific sonars by a single, solid elastic sphere is being adapted to acoustic backscatter (ABS) systems. Its first application, to the AQUAscat 1000, is described. The on-axis sensitivity and directional properties of transducer beams at three operating frequencies, nominally 1, 2.5, and 4 MHz, have been determined using a 10-mm-diameter sphere of tungsten carbide with 6% cobalt binder. Preliminary results are reported for the 1-MHz transducer. Their application to measurements of suspended sediment made in situ with the same device is described. This will enable the data to be expressed directly in physical units of volume backscattering.

  13. LASER monitoring system for the ATLAS Tile Calorimeter

    International Nuclear Information System (INIS)

    Viret, S.

    2010-01-01

    The ATLAS detector at the Large Hadron Collider (LHC) at CERN uses a scintillator-iron technique for its hadronic Tile Calorimeter (TileCal). Scintillating light is readout via 9852 photomultiplier tubes (PMTs). Calibration and monitoring of these PMTs are made using a LASER based system. Short light pulses are sent simultaneously into all the TileCal photomultiplier's tubes (PMTs) during ATLAS physics runs, thus providing essential information for ATLAS data quality and monitoring analyses. The experimental setup developed for this purpose is described as well as preliminary results obtained during ATLAS commissioning phase in 2008.

  14. Flux density calibration in diffuse optical tomographic systems.

    Science.gov (United States)

    Biswas, Samir Kumar; Rajan, Kanhirodan; Vasu, Ram M

    2013-02-01

    The solution of the forward equation that models the transport of light through a highly scattering tissue material in diffuse optical tomography (DOT) using the finite element method gives flux density (Φ) at the nodal points of the mesh. The experimentally measured flux (Umeasured) on the boundary over a finite surface area in a DOT system has to be corrected to account for the system transfer functions (R) of various building blocks of the measurement system. We present two methods to compensate for the perturbations caused by R and estimate true flux density (Φ) from Umeasuredcal. In the first approach, the measurement data with a homogeneous phantom (Umeasuredhomo) is used to calibrate the measurement system. The second scheme estimates the homogeneous phantom measurement using only the measurement from a heterogeneous phantom, thereby eliminating the necessity of a homogeneous phantom. This is done by statistically averaging the data (Umeasuredhetero) and redistributing it to the corresponding detector positions. The experiments carried out on tissue mimicking phantom with single and multiple inhomogeneities, human hand, and a pork tissue phantom demonstrate the robustness of the approach.

  15. CALIBRATION OF EQUILIBRIUM TIDE THEORY FOR EXTRASOLAR PLANET SYSTEMS

    International Nuclear Information System (INIS)

    Hansen, Brad M. S.

    2010-01-01

    We provide an 'effective theory' of tidal dissipation in extrasolar planet systems by empirically calibrating a model for the equilibrium tide. The model is valid to high order in eccentricity and parameterized by two constants of bulk dissipation-one for dissipation in the planet and one for dissipation in the host star. We are able to consistently describe the distribution of extrasolar planetary systems in terms of period, eccentricity, and mass (with a lower limit of a Saturn mass) with this simple model. Our model is consistent with the survival of short-period exoplanet systems, but not with the circularization period of equal mass stellar binaries, suggesting that the latter systems experience a higher level of dissipation than exoplanet host stars. Our model is also not consistent with the explanation of inflated planetary radii as resulting from tidal dissipation. The paucity of short-period planets around evolved A stars is explained as the result of enhanced tidal inspiral resulting from the increase in stellar radius with evolution.

  16. Multi-terawatt fusion laser systems

    International Nuclear Information System (INIS)

    Holzrichter, J.F.

    1993-01-01

    The evolution of laser fusion systems started with a description of the basic principles of the laser in 1959, then a physical demonstration showing 1000 Watts of peak optical power in 1961 to the present systems that deliver 10 14 watts of peak optical power, are presented. Physical limits to large systems are reviewed: thermal limits, material stress limits, structural limits and stability, parasitic coupling, measurement precision and diagnostics. The various steps of the fusion laser-system development process are then discussed through an historical presentation. 3 figs., 8 refs

  17. A real-time camera calibration system based on OpenCV

    Science.gov (United States)

    Zhang, Hui; Wang, Hua; Guo, Huinan; Ren, Long; Zhou, Zuofeng

    2015-07-01

    Camera calibration is one of the essential steps in the computer vision research. This paper describes a real-time OpenCV based camera calibration system, and developed and implemented in the VS2008 environment. Experimental results prove that the system to achieve a simple and fast camera calibration, compared with MATLAB, higher precision and does not need manual intervention, and can be widely used in various computer vision system.

  18. Infrared laser scattering system for plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Muraoka, K; Hiraki, N; Kawasaki, S [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics

    1975-05-01

    The possibility of observing the collective scattering of infrared laser light from plasmas is discussed in terms of the laser power requirement, the necessary optical system and the detector performance, and is shown to be feasible with the present day techniques to get the ion temperature by means of a CO/sub 2/ laser on theta pinch plasmas. Based on this estimate, the construction of the TEA CO/sub 2/ laser and the preparations of the optical components have been started and some preliminary results of these are described.

  19. Infrared laser scattering system for plasma diagnostics

    International Nuclear Information System (INIS)

    Muraoka, Katsunori; Hiraki, Naoji; Kawasaki, Shoji

    1975-01-01

    The possibility of observing the collective scattering of infrared laser light from plasmas is discussed in terms of the laser power requirement, the necessary optical system and the detector performance, and is shown to be feasible with the present day techniques to get the ion temperature by means of a CO 2 laser on theta pinch plasmas. Based on this estimate, the construction of the TEA CO 2 laser and the preparations of the optical components have been started and some preliminary results of these are described. (auth.)

  20. Multitube coaxial closed cycle gas laser system

    International Nuclear Information System (INIS)

    Davis, J.W.; Walch, A.P.

    1975-01-01

    A gas laser design capable of long term reliable operation in a commercial environment is disclosed. Various construction details which insulate the laser optics from mechanical distortions and vibrations inevitably present in the environment are developed. Also, a versatile optical cavity made up of modular units which render the basic laser configuration adaptable to alternate designs with different output capabilities is shown in detail. The system built around a convection laser operated in a closed cycle and the working medium is a gas which is excited by direct current electric discharges. (auth)

  1. Maximum respiratory pressure measuring system : calibration and evaluation of uncertainty

    NARCIS (Netherlands)

    Ferreira, J.L.; Pereira, N.C.; Oliveira Júnior, M.; Vasconcelos, F.H.; Parreira, V.F.; Tierra-Criollo, C.J.

    2010-01-01

    The objective of this paper is to present a methodology for the evaluation of uncertainties in the measurements results obtained during the calibration of a digital manovacuometer prototype (DM) with a load cell sensor pressure device incorporated. Calibration curves were obtained for both pressure

  2. Accurate and Simple Calibration of DLP Projector Systems

    DEFF Research Database (Denmark)

    Wilm, Jakob; Olesen, Oline Vinter; Larsen, Rasmus

    2014-01-01

    does not rely on an initial camera calibration, and so does not carry over the error into projector calibration. A radial interpolation scheme is used to convert features coordinates into projector space, thereby allowing for a very accurate procedure. This allows for highly accurate determination...

  3. A theoretical approach to calibrate radiation portal monitor (RPM) systems

    International Nuclear Information System (INIS)

    Nafee, Sherif S.; Abbas, Mahmoud I.

    2008-01-01

    Radiation portal monitor (RPM) systems are widely used at international border crossings, where they are applied to the task of detecting nuclear devices, special nuclear material, and radiation dispersal device materials that could appear at borders. The requirements and constraints on RPM systems deployed at high-volume border crossings are significantly different from those at weapons facilities or steel recycling plants, the former being required to rapidly detect localized sources of radiation with a very high detection probability and low false-alarm rate, while screening all of the traffic without impeding the flow of commerce [Chambers, W.H., Atwater, H.F., Fehlau, P.E., Hastings, R.D., Henry, C.N., Kunz, W.E., Sampson, T.E., Whittlesey, T.H., Worth, G.M., 1974. Portal Monitor for Diversion Safeguards. LA-5681, Los Alamos Scientific Laboratory, Los Alamos, NM]. In the present work, compact analytical formulae are derived and used to calibrate two RPM systems with isotropic radiating sources: (i) polyvinyltoluene (PVT) or plastic and (ii) thallium-doped crystalline sodium iodide, NaI(Tl), gamma-ray detector materials. The calculated efficiencies are compared to measured values reported in the literatures, showing very good agreement

  4. Automated calibration of laser spectrometer measurements of δ18 O and δ2 H values in water vapour using a Dew Point Generator.

    Science.gov (United States)

    Munksgaard, Niels C; Cheesman, Alexander W; Gray-Spence, Andrew; Cernusak, Lucas A; Bird, Michael I

    2018-06-30

    Continuous measurement of stable O and H isotope compositions in water vapour requires automated calibration for remote field deployments. We developed a new low-cost device for calibration of both water vapour mole fraction and isotope composition. We coupled a commercially available dew point generator (DPG) to a laser spectrometer and developed hardware for water and air handling along with software for automated operation and data processing. We characterised isotopic fractionation in the DPG, conducted a field test and assessed the influence of critical parameters on the performance of the device. An analysis time of 1 hour was sufficient to achieve memory-free analysis of two water vapour standards and the δ 18 O and δ 2 H values were found to be independent of water vapour concentration over a range of ≈20,000-33,000 ppm. The reproducibility of the standard vapours over a 10-day period was better than 0.14 ‰ and 0.75 ‰ for δ 18 O and δ 2 H values, respectively (1 σ, n = 11) prior to drift correction and calibration. The analytical accuracy was confirmed by the analysis of a third independent vapour standard. The DPG distillation process requires that isotope calibration takes account of DPG temperature, analysis time, injected water volume and air flow rate. The automated calibration system provides high accuracy and precision and is a robust, cost-effective option for long-term field measurements of water vapour isotopes. The necessary modifications to the DPG are minor and easily reversible. Copyright © 2018 John Wiley & Sons, Ltd.

  5. Laser systems with diamond optical elements

    International Nuclear Information System (INIS)

    Seitz, J.R.

    1975-01-01

    High power laser systems with optical elements of diamond having a thermal conductivity of at least 10 W/cm. 0 K at 300 0 K and an optical absorption at the laser beam wavelength of no more than 10 to 20 percent are described. (U.S.)

  6. Blue laser phase change recording system

    International Nuclear Information System (INIS)

    Hofmann, Holger; Dambach, S.Soeren; Richter, Hartmut

    2002-01-01

    The migration paths from DVD phase change recording with red laser to the next generation optical disk formats with blue laser and high NA optics are discussed with respect to optical aberration margins and disc capacities. A test system for the evaluation of phase change disks with more than 20 GB capacity is presented and first results of the recording performance are shown

  7. Feature-based automatic color calibration for networked camera system

    Science.gov (United States)

    Yamamoto, Shoji; Taki, Keisuke; Tsumura, Norimichi; Nakaguchi, Toshiya; Miyake, Yoichi

    2011-01-01

    In this paper, we have developed a feature-based automatic color calibration by using an area-based detection and adaptive nonlinear regression method. Simple color matching of chartless is achieved by using the characteristic of overlapping image area with each camera. Accurate detection of common object is achieved by the area-based detection that combines MSER with SIFT. Adaptive color calibration by using the color of detected object is calculated by nonlinear regression method. This method can indicate the contribution of object's color for color calibration, and automatic selection notification for user is performed by this function. Experimental result show that the accuracy of the calibration improves gradually. It is clear that this method can endure practical use of multi-camera color calibration if an enough sample is obtained.

  8. Analysis of calibration-free wavelength-scanned wavelength modulation spectroscopy for practical gas sensing using tunable diode lasers

    Science.gov (United States)

    Sun, K.; Chao, X.; Sur, R.; Goldenstein, C. S.; Jeffries, J. B.; Hanson, R. K.

    2013-12-01

    A novel strategy has been developed for analysis of wavelength-scanned, wavelength modulation spectroscopy (WMS) with tunable diode lasers (TDLs). The method simulates WMS signals to compare with measurements to determine gas properties (e.g., temperature, pressure and concentration of the absorbing species). Injection-current-tuned TDLs have simultaneous wavelength and intensity variation, which severely complicates the Fourier expansion of the simulated WMS signal into harmonics of the modulation frequency (fm). The new method differs from previous WMS analysis strategies in two significant ways: (1) the measured laser intensity is used to simulate the transmitted laser intensity and (2) digital lock-in and low-pass filter software is used to expand both simulated and measured transmitted laser intensities into harmonics of the modulation frequency, WMS-nfm (n = 1, 2, 3,…), avoiding the need for an analytic model of intensity modulation or Fourier expansion of the simulated WMS harmonics. This analysis scheme is valid at any optical depth, modulation index, and at all values of scanned-laser wavelength. The method is demonstrated and validated with WMS of H2O dilute in air (1 atm, 296 K, near 1392 nm). WMS-nfm harmonics for n = 1 to 6 are extracted and the simulation and measurements are found in good agreement for the entire WMS lineshape. The use of 1f-normalization strategies to realize calibration-free wavelength-scanned WMS is also discussed.

  9. A procedure for calibration and validation of FE modelling of laser-assisted metal to polymer direct joining

    Science.gov (United States)

    Lambiase, F.; Genna, S.; Kant, R.

    2018-01-01

    The quality of the joints produced by means of Laser-Assisted Metal to Polymer direct joining (LAMP) is strongly influenced by the temperature field produced during the laser treatment. The main phenomena including the adhesion of the plastic to the metal sheet and the development of bubbles (on the plastic surface) depend on the temperature reached by the polymer at the interface. Such a temperature should be higher than the softening temperature, but lower than the degradation temperature of the polymer. However, the temperature distribution is difficult to be measured by experimental tests since the most polymers (which are transparent to the laser radiation) are often opaque to the infrared wavelength. Thus, infrared analysis involving pyrometers and infrared camera is not suitable for this purpose. On the other hand, thermocouples are difficult to be placed at the interface without influencing the temperature conditions. In this paper, an integrated approach involving both experimental measurements and a Finite Element (FE) model were used to perform such an analysis. LAMP of Polycarbonate and AISI304 stainless steel was performed by means of high power diode laser and the main process parameters i.e. laser power and scanning speed were varied. Comparing the experimental measurements and the FE model prediction of the thermal field, a good correspondence was achieved proving the suitability of the developed model and the proposed calibration procedure to be ready used for process design and optimization.

  10. Note: An improved calibration system with phase correction for electronic transformers with digital output.

    Science.gov (United States)

    Cheng, Han-miao; Li, Hong-bin

    2015-08-01

    The existing electronic transformer calibration systems employing data acquisition cards cannot satisfy some practical applications, because the calibration systems have phase measurement errors when they work in the mode of receiving external synchronization signals. This paper proposes an improved calibration system scheme with phase correction to improve the phase measurement accuracy. We employ NI PCI-4474 to design a calibration system, and the system has the potential to receive external synchronization signals and reach extremely high accuracy classes. Accuracy verification has been carried out in the China Electric Power Research Institute, and results demonstrate that the system surpasses the accuracy class 0.05. Furthermore, this system has been used to test the harmonics measurement accuracy of all-fiber optical current transformers. In the same process, we have used an existing calibration system, and a comparison of the test results is presented. The system after improvement is suitable for the intended applications.

  11. Note: An improved calibration system with phase correction for electronic transformers with digital output

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Han-miao, E-mail: chenghanmiao@hust.edu.cn; Li, Hong-bin, E-mail: lihongbin@hust.edu.cn [CEEE of Huazhong University of Science and Technology, Wuhan 430074 (China); State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Wuhan 430074 (China)

    2015-08-15

    The existing electronic transformer calibration systems employing data acquisition cards cannot satisfy some practical applications, because the calibration systems have phase measurement errors when they work in the mode of receiving external synchronization signals. This paper proposes an improved calibration system scheme with phase correction to improve the phase measurement accuracy. We employ NI PCI-4474 to design a calibration system, and the system has the potential to receive external synchronization signals and reach extremely high accuracy classes. Accuracy verification has been carried out in the China Electric Power Research Institute, and results demonstrate that the system surpasses the accuracy class 0.05. Furthermore, this system has been used to test the harmonics measurement accuracy of all-fiber optical current transformers. In the same process, we have used an existing calibration system, and a comparison of the test results is presented. The system after improvement is suitable for the intended applications.

  12. Calibration of the OPAL jet chamber with UV laser beams. Measurement of the beam position with position-sensitive silicon diodes (PSD)

    International Nuclear Information System (INIS)

    Koch, J.

    1990-03-01

    The OPAL jet chamber is calibrated with tracks produced by UV laser beams. Lateral effect diodes are used for monitoring the laser beam location in the detector. These position sensitive detectors locate the point of impact in two dimensions by the charge division method. Measurements on several diodes were carried out in order to calibrate these devices and to investigate to observed pin-cushion distortion. Using the telegraphers equation suitable expressions were obtained for describing the observed behaviour. It was shown that the magnetic field of OPAL as well as the UV laser wavelength and puls duration had no influence on the position information. (orig.)

  13. Calibration and Monitoring systems of the ATLAS Tile Hadron Calorimeter

    CERN Document Server

    BOUMEDIENE, D; The ATLAS collaboration

    2012-01-01

    The TileCal is the hadronic calorimeter covering the most central region of the ATLAS experiment at LHC. It is a sampling calorimeter with iron plates as absorber and plastic scintillating tiles as the active material. The scintillation light produced by the passage of charged particles is transmitted by wavelength shifting fibers to about 10000 photomultiplier tubes (PMTs). Integrated on the calorimeter there is a composite device that allows to monitor and/or equalize the signals at various stages of its formation. This device is based on signal generation from different sources: radioactive, LASER and charge injection and minimum bias events produces in proton-proton collisions. In this contribution is given a brief description of the different systems hardware and presented the latest results on their performance, like the determination of the conversion factors, linearity and stability.

  14. Experiments on mobile robot stereo vision system calibration under hardware imperfection

    Directory of Open Access Journals (Sweden)

    Safin Ramil

    2018-01-01

    Full Text Available Calibration is essential for any robot vision system for achieving high accuracy in deriving objects metric information. One of typical requirements for a stereo vison system in order to obtain better calibration results is to guarantee that both cameras keep the same vertical level. However, cameras may be displaced due to severe conditions of a robot operating or some other circumstances. This paper presents our experimental approach to the problem of a mobile robot stereo vision system calibration under a hardware imperfection. In our experiments, we used crawler-type mobile robot «Servosila Engineer». Stereo system cameras of the robot were displaced relative to each other, causing loss of surrounding environment information. We implemented and verified checkerboard and circle grid based calibration methods. The two methods comparison demonstrated that a circle grid based calibration should be preferred over a classical checkerboard calibration approach.

  15. Calibration method for projector-camera-based telecentric fringe projection profilometry system.

    Science.gov (United States)

    Liu, Haibo; Lin, Huijing; Yao, Linshen

    2017-12-11

    By combining a fringe projection setup with a telecentric lens, a fringe pattern could be projected and imaged within a small area, making it possible to measure the three-dimensional (3D) surfaces of micro-components. This paper focuses on the flexible calibration of the fringe projection profilometry (FPP) system using a telecentric lens. An analytical telecentric projector-camera calibration model is introduced, in which the rig structure parameters remain invariant for all views, and the 3D calibration target can be located on the projector image plane with sub-pixel precision. Based on the presented calibration model, a two-step calibration procedure is proposed. First, the initial parameters, e.g., the projector-camera rig, projector intrinsic matrix, and coordinates of the control points of a 3D calibration target, are estimated using the affine camera factorization calibration method. Second, a bundle adjustment algorithm with various simultaneous views is applied to refine the calibrated parameters, especially the rig structure parameters and coordinates of the control points forth 3D target. Because the control points are determined during the calibration, there is no need for an accurate 3D reference target, whose is costly and extremely difficult to fabricate, particularly for tiny objects used to calibrate the telecentric FPP system. Real experiments were performed to validate the performance of the proposed calibration method. The test results showed that the proposed approach is very accurate and reliable.

  16. Coastal zone color scanner ``system calibration'': A retrospective examination

    Science.gov (United States)

    Evans, Robert H.; Gordon, Howard R.

    1994-04-01

    During its lifetime the coastal zone color scanner (CZCS) produced approximately 66,000 images. These have been placed in an archive of "raw" radiance (sensor counts) in a subsampled format that is easily accessible. They have also been processed to form global fields, at reduced resolution, of normalized water-leaving radiance, phytoplankton pigments, and diffuse attenuation coefficient. Using this archive, we have tried to characterize some aspects of the "system calibration" for the 8-year lifetime of CZCS. Specifically, we have assumed that the sensitivity of the red band decayed in a simple manner similar to the well-known long-term degradation of the shorter-wavelength bands, and we examined the sensitivity of the green and yellow bands by computing the globally averaged water-leaving radiance, over 10-day periods, for all of the imagery. The results provide evidence that in addition to the long-term degradation, short-term (2 weeks to 1 month) variations in the radiometric sensitivity of these bands started in early fall 1981 and continued for the rest of the mission. In contrast, the data suggest the absence of such variations prior to August 1981. It is reasonable to believe that the sensitivity of the blue (and probably the red) band underwent such variations as well; however, our methodology cannot be used to study the other bands. Thus after these fluctuations began, the actual values of CZCS-estimated pigment concentrations at a given location should be viewed with skepticism; however, the global patterns of derived pigment concentration should be valid. Had an extensive set of surface measurements of water-leaving radiance, e.g., from moored buoys or drifters, been available during the CZCS mission, these fluctuations could have been removed from the data set, and this would have greatly increased its value. The lessons learned from CZCS, that is, the requirement of good radiometric calibration and stability and the necessity of "sea truth" stations

  17. Coastal zone color scanner 'system calibration': A retrospective examination

    Science.gov (United States)

    Evans, Robert H.; Gordon, Howard R.

    1994-01-01

    During its lifetime the Coastal Zone Color Scanner (CZCS) produced approximately 66,000 images. These have been placed in an archive of 'raw' radiance (sensor counts) in a subsampled format that is easily accessible. They have also been processed to form global fields, at reduced resolution, of normalized water-leaving radiance, phytoplankton pigments, and diffuse attenuation coefficient. Using this archive, we have tried to characterize some aspects of the 'system calibration' for the 8-year lifetime of CZCS. Specifically, we have assumed that the sensitivity of the red band decayed in a simple manner similar to the well-known long-term degradation of the shorter-wavelength bands, and we examined the sensitivity of the green and yellow bands by computing the globally averaged water-leaving radiance, over 10-day periods, for all of the imagery. The results provided evidence that in addition to the long-term degradation, short-term (2 weeks to 1 month) variations in the radiometric sensitivity of these bands started in early fall 1981 and continued for the rest of the mission. In contrast, the data suggested the absence of such variations prior to August 1981. It is reasonable to believe that the sensitivity of the blue (and probably the red) band underwent such variations as well; however our methodology cannot be used to study the other bands. Thus, after these fluctuations began, the actual values of CZCS - estimated pigment concentrations at a given location should be viewed with skepticism; however, the global patterns of derived pigment concentrations should be valid. Had an extensive set of surface measurements of water-leaving radiance, e.r., from moored buoyes or drifters, had been available during the CZCS mission, these fluctuations could have been removed from the data set, and this would have greatly increased its value. The lessons learned from CZCS that is, the requirement of good radiometric calibration and stability and the necessity of 'sea truth

  18. Magnetically switched power supply system for lasers

    Science.gov (United States)

    Pacala, Thomas J. (Inventor)

    1987-01-01

    A laser power supply system is described in which separate pulses are utilized to avalanche ionize the gas within the laser and then produce a sustained discharge to cause the gas to emit light energy. A pulsed voltage source is used to charge a storage device such as a distributed capacitance. A transmission line or other suitable electrical conductor connects the storage device to the laser. A saturable inductor switch is coupled in the transmission line for containing the energy within the storage device until the voltage level across the storage device reaches a predetermined level, which level is less than that required to avalanche ionize the gas. An avalanche ionization pulse generating circuit is coupled to the laser for generating a high voltage pulse of sufficient amplitude to avalanche ionize the laser gas. Once the laser gas is avalanche ionized, the energy within the storage device is discharged through the saturable inductor switch into the laser to provide the sustained discharge. The avalanche ionization generating circuit may include a separate voltage source which is connected across the laser or may be in the form of a voltage multiplier circuit connected between the storage device and the laser.

  19. Mammography calibration qualities establishment in a Mo-Mo clinical system

    International Nuclear Information System (INIS)

    Correa, E.L.; Santos, L.R. dos; Vivolo, V.; Potiens, M.P.A.

    2015-01-01

    In this study the mammography calibration qualities were established in a clinical mammography system. The objective is to provide the IPEN instruments calibration laboratory with both mammography calibration methods (using a clinical and an industrial system). The results showed a good behavior of mammography equipment, in terms of kVp, PPV and exposure time. The additional filtration of molybdenum is adequate, air-kerma rates were determined and spectra were obtained. (author)

  20. Mammography calibration qualities establishment in a Mo-Mo clinical system

    Energy Technology Data Exchange (ETDEWEB)

    Correa, E.L.; Santos, L.R. dos; Vivolo, V.; Potiens, M.P.A., E-mail: educorrea1905@gmail.com [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    In this study the mammography calibration qualities were established in a clinical mammography system. The objective is to provide the IPEN instruments calibration laboratory with both mammography calibration methods (using a clinical and an industrial system). The results showed a good behavior of mammography equipment, in terms of kVp, PPV and exposure time. The additional filtration of molybdenum is adequate, air-kerma rates were determined and spectra were obtained. (author)

  1. Alignment of the measurement scale mark during immersion hydrometer calibration using an image processing system.

    Science.gov (United States)

    Peña-Perez, Luis Manuel; Pedraza-Ortega, Jesus Carlos; Ramos-Arreguin, Juan Manuel; Arriaga, Saul Tovar; Fernandez, Marco Antonio Aceves; Becerra, Luis Omar; Hurtado, Efren Gorrostieta; Vargas-Soto, Jose Emilio

    2013-10-24

    The present work presents an improved method to align the measurement scale mark in an immersion hydrometer calibration system of CENAM, the National Metrology Institute (NMI) of Mexico, The proposed method uses a vision system to align the scale mark of the hydrometer to the surface of the liquid where it is immersed by implementing image processing algorithms. This approach reduces the variability in the apparent mass determination during the hydrostatic weighing in the calibration process, therefore decreasing the relative uncertainty of calibration.

  2. Generic System for Remote Testing and Calibration of Measuring Instruments: Security Architecture

    Science.gov (United States)

    Jurčević, M.; Hegeduš, H.; Golub, M.

    2010-01-01

    Testing and calibration of laboratory instruments and reference standards is a routine activity and is a resource and time consuming process. Since many of the modern instruments include some communication interfaces, it is possible to create a remote calibration system. This approach addresses a wide range of possible applications and permits to drive a number of different devices. On the other hand, remote calibration process involves a number of security issues due to recommendations specified in standard ISO/IEC 17025, since it is not under total control of the calibration laboratory personnel who will sign the calibration certificate. This approach implies that the traceability and integrity of the calibration process directly depends on the collected measurement data. The reliable and secure remote control and monitoring of instruments is a crucial aspect of internet-enabled calibration procedure.

  3. Target isolation system, high power laser and laser peening method and system using same

    Science.gov (United States)

    Dane, C. Brent; Hackel, Lloyd A.; Harris, Fritz

    2007-11-06

    A system for applying a laser beam to work pieces, includes a laser system producing a high power output beam. Target delivery optics are arranged to deliver the output beam to a target work piece. A relay telescope having a telescope focal point is placed in the beam path between the laser system and the target delivery optics. The relay telescope relays an image between an image location near the output of the laser system and an image location near the target delivery optics. A baffle is placed at the telescope focal point between the target delivery optics and the laser system to block reflections from the target in the target delivery optics from returning to the laser system and causing damage.

  4. Calibration technique for the neutron surface moisture measurement system

    International Nuclear Information System (INIS)

    Watson, W.T.; Shreve, D.C.

    1996-01-01

    A technique for calibrating the response of a surface neutron moisture measurement probe to material moisture concentration has been devised. Tests to ensure that the probe will function in the expected in-tank operating environment are also outlined

  5. Quantitative analysis of Al-Si alloy using calibration free laser induced breakdown spectroscopy (CF-LIBS)

    Science.gov (United States)

    Shakeel, Hira; Haq, S. U.; Aisha, Ghulam; Nadeem, Ali

    2017-06-01

    The quantitative analysis of the standard aluminum-silicon alloy has been performed using calibration free laser induced breakdown spectroscopy (CF-LIBS). The plasma was produced using the fundamental harmonic (1064 nm) of the Nd: YAG laser and the emission spectra were recorded at 3.5 μs detector gate delay. The qualitative analysis of the emission spectra confirms the presence of Mg, Al, Si, Ti, Mn, Fe, Ni, Cu, Zn, Sn, and Pb in the alloy. The background subtracted and self-absorption corrected emission spectra were used for the estimation of plasma temperature as 10 100 ± 300 K. The plasma temperature and self-absorption corrected emission lines of each element have been used for the determination of concentration of each species present in the alloy. The use of corrected emission intensities and accurate evaluation of plasma temperature yield reliable quantitative analysis up to a maximum 2.2% deviation from reference sample concentration.

  6. Remote calibration system of a smart electrical energy meter

    Directory of Open Access Journals (Sweden)

    Zakariae Jebroni

    2017-12-01

    Full Text Available The need to control the power grid in real time has opened a new field of research, today researchers are trying to design electrical meters that are completely remote controlled, to create an advanced metering infrastructure. One of the most important processes in the field of measurement is the calibration of measuring instruments. The calibration process of the electrical meters was performed at laboratories. However, the new directives, now, require a regular test of accuracy. Nevertheless, moving each time on site to check the accuracy of a meter can be annoying. To solve this problem our contribution is to propose a new structure of a smart meter that integrates a calibration card, so that, this process is carried out remotely. To be able to calibrate the meter or test its accuracy, we have included an AC-AC converter powered by the electrical grid and that provides a stable voltage independent of the electrical grid in term of frequency and amplitude. The output voltage of the converter is used as the reference signal during calibration or accuracy testing. In this paper, we will present the structure of the calibration card, the study and dimensioning of the converter, as well as the control technique used to eliminate variations of the input voltage. At the end, we will present the results of simulations and experiments.

  7. A vision-based system for fast and accurate laser scanning in robot-assisted phonomicrosurgery.

    Science.gov (United States)

    Dagnino, Giulio; Mattos, Leonardo S; Caldwell, Darwin G

    2015-02-01

    Surgical quality in phonomicrosurgery can be improved by open-loop laser control (e.g., high-speed scanning capabilities) with a robust and accurate closed-loop visual servoing systems. A new vision-based system for laser scanning control during robot-assisted phonomicrosurgery was developed and tested. Laser scanning was accomplished with a dual control strategy, which adds a vision-based trajectory correction phase to a fast open-loop laser controller. The system is designed to eliminate open-loop aiming errors caused by system calibration limitations and by the unpredictable topology of real targets. Evaluation of the new system was performed using CO(2) laser cutting trials on artificial targets and ex-vivo tissue. This system produced accuracy values corresponding to pixel resolution even when smoke created by the laser-target interaction clutters the camera view. In realistic test scenarios, trajectory following RMS errors were reduced by almost 80 % with respect to open-loop system performances, reaching mean error values around 30 μ m and maximum observed errors in the order of 60 μ m. A new vision-based laser microsurgical control system was shown to be effective and promising with significant positive potential impact on the safety and quality of laser microsurgeries.

  8. Development of basic system for sensor calibration support in nuclear power plants

    International Nuclear Information System (INIS)

    Kusumi, Naohiro; Ohga, Yukiharu; Fukuda, Mitsuko; Ishizaki, Yuuichi; Koyama, Mikio; Maeda, Akihiko

    2004-01-01

    It is strongly desirable to reduce maintenance costs and shorten the time of periodic inspections in nuclear power plants. Therefore, it is important to reduce the amount of maintenance work during the inspection. In Japan, sensor calibration is usually performed at every periodic inspection, and the sensor calibration requires a large amount of work. A system for sensor calibration support has been developed to reduce sensor calibration work. The system is composed of two subsystems: a statistical analysis subsystem and a drift detection subsystem, as well as a human-machine interface, which offers support information. The statistical analysis subsystem supports the decision of the sensor calibration intervals based on the statistical analysis of sensor calibration data. There is the possibility that sensor drift increases beyond an allowance value before the sensor calibration intervals determined by the statistical analysis subsystem because of malfunctions, etc. To cope with this, the drift detection subsystem detects the sensor drift online during the plant operation. By combining the statistical analysis subsystem and the drift detection subsystem, a reliable sensor calibration support system is realized. The basic system composed of two subsystems was developed and evaluated using real plant data. The results showed that the sensor calibration intervals can be extended beyond current intervals and that the system is capable of detecting the sensor drift online. (author)

  9. Reflective terahertz (THz) imaging: system calibration using hydration phantoms

    Science.gov (United States)

    Bajwa, Neha; Garritano, James; Lee, Yoon Kyung; Tewari, Priyamvada; Sung, Shijun; Maccabi, Ashkan; Nowroozi, Bryan; Babakhanian, Meghedi; Sanghvi, Sajan; Singh, Rahul; Grundfest, Warren; Taylor, Zachary

    2013-02-01

    Terahertz (THz) hydration sensing continues to gain traction in the medical imaging community due to its unparalleled sensitivity to tissue water content. Rapid and accurate detection of fluid shifts following induction of thermal skin burns as well as remote corneal hydration sensing have been previously demonstrated in vivo using reflective, pulsed THz imaging. The hydration contrast sensing capabilities of this technology were recently confirmed in a parallel 7 Tesla Magnetic Resonance (MR) imaging study, in which burn areas are associated with increases in local mobile water content. Successful clinical translation of THz sensing, however, still requires quantitative assessments of system performance measurements, specifically hydration concentration sensitivity, with tissue substitutes. This research aims to calibrate the sensitivity of a novel, reflective THz system to tissue water content through the use of hydration phantoms for quantitative comparisons of THz hydration imagery.Gelatin phantoms were identified as an appropriate tissue-mimicking model for reflective THz applications, and gel composition, comprising mixtures of water and protein, was varied between 83% to 95% hydration, a physiologically relevant range. A comparison of four series of gelatin phantom studies demonstrated a positive linear relationship between THz reflectivity and water concentration, with statistically significant hydration sensitivities (p hydration). The THz-phantom interaction is simulated with a three-layer model using the Transfer Matrix Method with agreement in hydration trends. Having demonstrated the ability to accurately and noninvasively measure water content in tissue equivalent targets with high sensitivity, reflective THz imaging is explored as a potential tool for early detection and intervention of corneal pathologies.

  10. Repetitive output laser system and method using target reflectivity

    International Nuclear Information System (INIS)

    Johnson, R.R.

    1978-01-01

    An improved laser system and method for implosion of a thermonuclear fuel pellet is described in which that portion of a laser pulse reflected by the target pellet is utilized in the laser system to initiate a succeeding target implosion, and in which the energy stored in the laser system to amplify the initial laser pulse, but not completely absorbed thereby, is used to amplify succeeding laser pulses initiated by target refγlection

  11. Laser puncture therapy of nervous system disorders

    Energy Technology Data Exchange (ETDEWEB)

    Anishchenko, G.; Kochetkov, V.

    1984-08-29

    The authors discuss experience with treatment of nervous system disorders by means of laser-puncture therapy. Commenting on the background of the selection of this type of treatment, they explain that once researchers determined the biological action of laser light on specific nerve receptors of the skin, development of laser apparatus capable of concentrating the beam in the millimeter band was undertaken. The devices that are being used for laser-puncture are said to operate in the red helium-neon band of light. The authors identify beam parameters that have been selected for different groups of acupuncture points of the skin, and the courses of treatment (in seconds of radiation) and their time intervals. They go on to discuss the results of treatment of over 800 patients categorized in a group with disorders of the peripheral nervous system and a second group with disorders of the central nervous system.

  12. A flexible approach to light pen calibration for a monocular-vision-based coordinate measuring system

    International Nuclear Information System (INIS)

    Fu, Shuai; Zhang, Liyan; Ye, Nan; Liu, Shenglan; Zhang, WeiZhong

    2014-01-01

    A monocular-vision-based coordinate measuring system (MVB-CMS) obtains the 3D coordinates of the probe tip center of a light pen by analyzing the monocular image of the target points on the light pen. The light pen calibration, including the target point calibration and the probe tip center calibration, is critical to guarantee the accuracy of the MVB-CMS. The currently used method resorts to special equipment to calibrate the feature points on the light pen in a separate offsite procedure and uses the system camera to calibrate the probe tip center onsite. Instead, a complete onsite light pen calibration method is proposed in this paper. It needs only several auxiliary target points with the same visual features of the light pen targets and two or more cone holes with known distance(s). The target point calibration and the probe tip center calibration are jointly implemented by simply taking two groups of images of the light pen with the camera of the system. The proposed method requires no extra equipment other than the system camera for the calibration, so it is easier to implement and flexible for use. It has been incorporated in a large field-of-view MVB-CMS, which uses active luminous infrared LEDs as the target points. Experimental results demonstrate the accuracy and effectiveness of the proposed method. (paper)

  13. Calibration of a camera–projector measurement system and error impact analysis

    International Nuclear Information System (INIS)

    Huang, Junhui; Wang, Zhao; Xue, Qi; Gao, Jianmin

    2012-01-01

    In the camera–projector measurement system, calibration is a key to the measurement accuracy; especially, it is more difficult to obtain the same calibration accuracy for projector than camera due to the inaccurate corresponding relationship between its calibration points and imaging points. Thus, based on stereo vision measurement models of the camera and the projector, a calibration method with direct linear transformation (DLT) and bundle adjustment (BA) is introduced to adjust the corresponding relationships for better optimization purpose in this paper, which minimize the effect of inaccurate calibration points. And an integral method is presented to improve the precision of projection patterns to compensate the projector resolution limitation. Moreover impacts of system parameter and calibration points errors are evaluated when the calibration points positions change, which not only provides theoretical guidance for the rational layout of the calibration points, but also can be used for the optimization of system structure. Finally, the calibration of the system is carried out and the experiment results show that better precision can be achieved with those processes. (paper)

  14. Investigation into the verification of the Synapsys videonystagmography (VNG) Ulmer calibration system.

    Science.gov (United States)

    Corless, Natalie; Goggins, Susannah

    2014-09-01

    To assess the accuracy and stability of the Synapsys VNG Ulmer calibration system when the goggles and infrared camera are repositioned, and the accuracy of the equipment's geometric calibration system. Prospective data collection involved participants conducting the system's horizontal calibration test. Eye measurements were then recorded for a 60° deviation (looking from 30° right to -30° left) and repeated after the goggles and infrared camera were removed/repositioned. Participants' eye measurements were also recorded after the geometric calibration had been activated. Twenty-two participants with no history of visual or vestibular pathology were recruited for this study. No significant differences were found when the goggles were removed and replaced (p = 0.21); when the infrared camera was repositioned within the goggles (p = 0.50); or when the goggles were removed and the camera repositioned (p = 0.18) after horizontal calibration. A significant difference was found during the assessment of geometric calibration (p < 0.01). Calibration is not affected by removal or repositioning of the goggles and/or infrared camera within the goggles, therefore suggesting recalibration may not be necessary. Caution should be exercised when using the equipment's geometric calibration and should only be used when the patient is unable to conduct the system's horizontal calibration test.

  15. Testing and calibration through laser radiation and muon beams of the hadron calorimeter in ATLAS detector; Controle et etalonnage par lumiere laser et par faisceaux de muons du calorimetre hadronique a tuiles scintillantes d'ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Garde, V

    2003-10-15

    This study is dedicated to the calibration of the hadronic calorimeter (Tilecal) of the ATLAS detector. This detector will be installed on the LHC collider at CERN. The first data will be taken in 2007. This thesis is divided in two parts. The first part is dedicated to the study of the LASER system. A prototype of the final system was studied. It was shown that the stability and the linearity of this prototype are conform to the specification. Several studies were devoted to measurements which can be done on the Tilecal: The relative gain can be calculated and gives the stability of the Tilecal with a resolution of 0.35 %. The number of photoelectrons per charge unit has been calculated. The linearity was checked for a normal range of functioning and was corrected for the functioning at high charge. In both cases it was shown that the non-linearity was smaller than 0.5 %. The second study is devoted to muons beams in test beam periods. These results are used to find a calibration constant. Several problems which come from the difference of size cells are not totally solved. But the resolution of the calibration constant found by this method cannot exceed 2.3%. (author)

  16. ISOLDE gets a new laser system

    CERN Multimedia

    Anaïs Schaeffer

    2011-01-01

    It's action stations at ISOLDE, the On-Line Isotope Mass Separator at CERN. The Laboratory is preparing to add a second laser ion source system to its arsenal. By alternating between two laser systems, the ISOLDE team will be able to switch from one type of beam to another in record time.   Bruce Marsh, from the EN-STI Group, with one of the lasers from ISOLDE's current system. The first laser source for producing radioactive ion beams (see box) was installed in the ISOLDE hall in the 1990s. This method, which was highly innovative for its time, has since been adopted by several laboratories all over the world. "This laser system allows us to control the ionisation wavelength with precision and thus to select specific atoms in order to produce very pure radioactive ion beams," explains Valentin Fedosseev of the EN Department. "These beams are then used for various experiments, in nuclear astrophysics and biology, for example. With two laser systems we will be able to do ...

  17. Calibration and consistency of results of an ionization-chamber secondary standard measuring system for activity

    International Nuclear Information System (INIS)

    Schrader, Heinrich

    2000-01-01

    Calibration in terms of activity of the ionization-chamber secondary standard measuring systems at the PTB is described. The measurement results of a Centronic IG12/A20, a Vinten ISOCAL IV and a radionuclide calibrator chamber for nuclear medicine applications are discussed, their energy-dependent efficiency curves established and the consistency checked using recently evaluated radionuclide decay data. Criteria for evaluating and transferring calibration factors (or efficiencies) are given

  18. Large laser system facility design

    International Nuclear Information System (INIS)

    Gilmartin, T.J.

    1983-01-01

    Optical stability of foundations and support structures, environmental control, close-in subsystem integration, spatial organization, materiel flow and access to remote subsystems is discussed and compared for four laser facilities: The Special Isotope Separation Laboratory, Argus, Shiva/Nova, and Firepond

  19. Laser systems for ablative fractional resurfacing

    DEFF Research Database (Denmark)

    Paasch, Uwe; Haedersdal, Merete

    2011-01-01

    of a variety of skin conditions, primarily chronically photodamaged skin, but also acne and burn scars. In addition, it is anticipated that AFR can be utilized in the laser-assisted delivery of topical drugs. Clinical efficacy coupled with minimal downtime has driven the development of various fractional...... ablative laser systems. Fractionated CO(2) (10,600-nm), erbium yttrium aluminum garnet, 2940-nm and yttrium scandium gallium garnet, 2790-nm lasers are available. In this article, we present an overview of AFR technology, devices and histopathology, and we summarize the current clinical possibilities...

  20. Laser systems for ablative fractional resurfacing

    DEFF Research Database (Denmark)

    Paasch, Uwe; Haedersdal, Merete

    2011-01-01

    ablative laser systems. Fractionated CO(2) (10,600-nm), erbium yttrium aluminum garnet, 2940-nm and yttrium scandium gallium garnet, 2790-nm lasers are available. In this article, we present an overview of AFR technology, devices and histopathology, and we summarize the current clinical possibilities...... of a variety of skin conditions, primarily chronically photodamaged skin, but also acne and burn scars. In addition, it is anticipated that AFR can be utilized in the laser-assisted delivery of topical drugs. Clinical efficacy coupled with minimal downtime has driven the development of various fractional...

  1. The study of new calibration features in the Harshaw TLD system

    International Nuclear Information System (INIS)

    Luo, L.Z.

    2005-01-01

    Full text: In the Harshaw TLD system, there are three key calibration procedures; the reader, the dosimeter and the algorithm. These procedures must be properly calibrated for the system to achieve the optimum results. For the conventional reader and dosimeter calibration, Harshaw recommends a pre-fade and a post-fade of 24 - 48 hours when calibrating the system. Harshaw also emphasizes that keeping the fade time consistent is important to maintain the quality of the system performance. In recent years, new calibration features have been introduced into the operating system. These new features are auto calibration, auto QC and auto blank, and they give the user the ability to set up the clear-expose-read performed automatically in a sequence for each dosimeter. This saves processing time and keeps the fade time the same. However, since the fade time is near zero, will it affect the TLD system calibration factors? What should the user expect? This paper presents a study of the effect of auto calibration / auto QC to the TLD operation. (author)

  2. The study of new calibration features in the Harshaw TLD system

    International Nuclear Information System (INIS)

    Luo, L. Z.

    2007-01-01

    The Harshaw TLD system has three key calibration procedures: the Reader, the Dosemeter and the Algorithm. These functions must be properly calibrated for the system to achieve the optimum results. For the conventional reader and dosemeter calibration, Harshaw TLD recommends a pre-fade and a post-fade of 24-48 h when calibrating the system for LiF:Mg,Ti type dosemeter. It is also recommended that keeping the fade time consistent is important to maintain the quality of the system performance. In recent years, new calibration features have been introduced into the Harshaw TLD models 6600 and 8800 operating systems. These new features are Auto Calibration, Auto QC and Auto Blank, and they give the user the ability to set up the clear-expose-read process to be performed automatically in a sequence for each dosemeter. This saves processing time and keeps the fade time the same. However, since the fade time is near zero, will it affect the TLD system calibration factors? What should the user expect? This paper presents a study of the effect of Auto Calibration/Auto QC to the TLD operation. (authors)

  3. Robot calibration with a photogrammetric on-line system using reseau scanning cameras

    Science.gov (United States)

    Diewald, Bernd; Godding, Robert; Henrich, Andreas

    1994-03-01

    The possibility for testing and calibration of industrial robots becomes more and more important for manufacturers and users of such systems. Exacting applications in connection with the off-line programming techniques or the use of robots as measuring machines are impossible without a preceding robot calibration. At the LPA an efficient calibration technique has been developed. Instead of modeling the kinematic behavior of a robot, the new method describes the pose deviations within a user-defined section of the robot's working space. High- precision determination of 3D coordinates of defined path positions is necessary for calibration and can be done by digital photogrammetric systems. For the calibration of a robot at the LPA a digital photogrammetric system with three Rollei Reseau Scanning Cameras was used. This system allows an automatic measurement of a large number of robot poses with high accuracy.

  4. Onboard calibration igneous targets for the Mars Science Laboratory Curiosity rover and the Chemistry Camera laser induced breakdown spectroscopy instrument

    Energy Technology Data Exchange (ETDEWEB)

    Fabre, C., E-mail: cecile.fabre@g2r.uhp-nancy.fr [G2R, Nancy Universite (France); Maurice, S.; Cousin, A. [IRAP, Toulouse (France); Wiens, R.C. [LANL, Los Alamos, NM (United States); Forni, O. [IRAP, Toulouse (France); Sautter, V. [MNHN, Paris (France); Guillaume, D. [GET, Toulouse (France)

    2011-03-15

    Accurate characterization of the Chemistry Camera (ChemCam) laser-induced breakdown spectroscopy (LIBS) on-board composition targets is of prime importance for the ChemCam instrument. The Mars Science Laboratory (MSL) science and operations teams expect ChemCam to provide the first compositional results at remote distances (1.5-7 m) during the in situ analyses of the Martian surface starting in 2012. Thus, establishing LIBS reference spectra from appropriate calibration standards must be undertaken diligently. Considering the global mineralogy of the Martian surface, and the possible landing sites, three specific compositions of igneous targets have been determined. Picritic, noritic, and shergottic glasses have been produced, along with a Macusanite natural glass. A sample of each target will fly on the MSL Curiosity rover deck, 1.56 m from the ChemCam instrument, and duplicates are available on the ground. Duplicates are considered to be identical, as the relative standard deviation (RSD) of the composition dispersion is around 8%. Electronic microprobe and laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) analyses give evidence that the chemical composition of the four silicate targets is very homogeneous at microscopic scales larger than the instrument spot size, with RSD < 5% for concentration variations > 0.1 wt.% using electronic microprobe, and < 10% for concentration variations > 0.01 wt.% using LA ICP-MS. The LIBS campaign on the igneous targets performed under flight-like Mars conditions establishes reference spectra for the entire mission. The LIBS spectra between 240 and 900 nm are extremely rich, hundreds of lines with high signal-to-noise, and a dynamical range sufficient to identify unambiguously major, minor and trace elements. For instance, a first LIBS calibration curve has been established for strontium from [Sr] = 284 ppm to [Sr] = 1480 ppm, showing the potential for the future calibrations for other major or minor

  5. Onboard calibration igneous targets for the Mars Science Laboratory Curiosity rover and the Chemistry Camera laser induced breakdown spectroscopy instrument

    International Nuclear Information System (INIS)

    Fabre, C.; Maurice, S.; Cousin, A.; Wiens, R.C.; Forni, O.; Sautter, V.; Guillaume, D.

    2011-01-01

    Accurate characterization of the Chemistry Camera (ChemCam) laser-induced breakdown spectroscopy (LIBS) on-board composition targets is of prime importance for the ChemCam instrument. The Mars Science Laboratory (MSL) science and operations teams expect ChemCam to provide the first compositional results at remote distances (1.5-7 m) during the in situ analyses of the Martian surface starting in 2012. Thus, establishing LIBS reference spectra from appropriate calibration standards must be undertaken diligently. Considering the global mineralogy of the Martian surface, and the possible landing sites, three specific compositions of igneous targets have been determined. Picritic, noritic, and shergottic glasses have been produced, along with a Macusanite natural glass. A sample of each target will fly on the MSL Curiosity rover deck, 1.56 m from the ChemCam instrument, and duplicates are available on the ground. Duplicates are considered to be identical, as the relative standard deviation (RSD) of the composition dispersion is around 8%. Electronic microprobe and laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) analyses give evidence that the chemical composition of the four silicate targets is very homogeneous at microscopic scales larger than the instrument spot size, with RSD 0.1 wt.% using electronic microprobe, and 0.01 wt.% using LA ICP-MS. The LIBS campaign on the igneous targets performed under flight-like Mars conditions establishes reference spectra for the entire mission. The LIBS spectra between 240 and 900 nm are extremely rich, hundreds of lines with high signal-to-noise, and a dynamical range sufficient to identify unambiguously major, minor and trace elements. For instance, a first LIBS calibration curve has been established for strontium from [Sr] = 284 ppm to [Sr] = 1480 ppm, showing the potential for the future calibrations for other major or minor elements.

  6. Wavefront compensation applied to AVLIS laser systems

    International Nuclear Information System (INIS)

    Gonsiorowski, T.; Wirth, A.

    1995-01-01

    The efficiency of an AVLIS system depends upon the power density and uniformity of the laser system. Because of wavefront aberrations the realized beam quality is not ideal. Wavefront compensation provides a means to improve beam quality and system efficiency. (author)

  7. Calibration of the beam-position monitor system for the SLAC PEP-II B factory

    International Nuclear Information System (INIS)

    Johnson, R.; Smith, S.; Kurita, N.

    1997-06-01

    The Beam-Position Monitors (BPM) for the PEP-II B Factory consist of four 1.5-cm diameter button style pickups mounted on the diagonals of the quadrupole vacuum chambers. Before installation of the vacuum chambers in the quadrupole assemblies, the electrical center of the BPMs is measured with respect to the mechanical center in a calibration test stand. In this paper the calibration test stand is described and the precision and accuracy of the calibrations are presented. After installation of the quadrupole assemblies in the PEP-II tunnel, the passive attenuation for each channel of the system is measured to preserve the accuracy of the calibration. Finally, the active electronics includes an onboard calibrator. Results for these portions of the calibration are presented

  8. Research on calibration field designing for airborne position and orientation system

    Science.gov (United States)

    Fu, Jianhong

    2009-10-01

    To analyze the size and location of the calibration field and the stabilization of systematic error parameters, calibration field designing for airborne Position and Orientation System (POS) using actual photogrammetric data is discussed in this paper. The empirical results have verified that a region of 4 strips with 7 images in each strip is appropriate for use as a calibration field, whose location should be within 1° in longitude from the center of the project. If the equipment is changed, the POS must be recalibrated. Otherwise, the flight interval of the calibration field should not exceed 30 days.

  9. Robotic Laser Coating Removal System

    Science.gov (United States)

    2008-07-01

    using a transverse excitation at atmospheric pressure (TEA) method. o Excimer lasers use reactive gases, such as chlorine and fluorine , mixed with... Varnish , and Related Products on Test Panels.   All topcoats were applied over the primer within the manufacturer’s recommended time and  artificially aged

  10. Reliability of an x-ray system for calibrating and testing personal radiation dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Guimarães, M.C.; Silva, C.R.E.; Silva, T.A. da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Rosado, P.H.G.; Cunha, P.G. [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    Metrology laboratories are expected to maintain standardized radiation beams and traceable standard dosimeters to provide reliable calibrations or testing of detectors. Results of the characterization of an x-ray system for performing calibration and testing of radiation dosimeters used for individual monitoring are shown in this work. (author)

  11. Reliability of an x-ray system for calibrating and testing personal radiation dosimeters

    Science.gov (United States)

    Guimarães, M. C.; Silva, C. R. E.; Rosado, P. H. G.; Cunha, P. G.; Da Silva, T. A.

    2018-03-01

    Metrology laboratories are expected to maintain standardized radiation beams and traceable standard dosimeters to provide reliable calibrations or testing of detectors. Results of the characterization of an x-ray system for performing calibration and testing of radiation dosimeters used for individual monitoring are shown in this work.

  12. Reliability of an x-ray system for calibrating and testing personal radiation dosimeters

    International Nuclear Information System (INIS)

    Guimarães, M.C.; Silva, C.R.E.; Silva, T.A. da; Rosado, P.H.G.; Cunha, P.G.

    2017-01-01

    Metrology laboratories are expected to maintain standardized radiation beams and traceable standard dosimeters to provide reliable calibrations or testing of detectors. Results of the characterization of an x-ray system for performing calibration and testing of radiation dosimeters used for individual monitoring are shown in this work. (author)

  13. Laser surveillance system for spent fuel

    International Nuclear Information System (INIS)

    Fiarman, S.; Zucker, M.S.; Bieber, A.M. Jr.

    1980-01-01

    A laser surveillance system installed at spent fuel storage pools will provide the safeguard inspector with specific knowledge of spent fuel movement that cannot be obtained with current surveillance systems. The laser system will allow for the division of the pool's spent fuel inventory into two populations - those assemblies which have been moved and those which haven't - which is essential for maximizing the efficiency and effectiveness of the inspection effort. We have designed, constructed, and tested a laser system and have used it with a simulated BWR assembly. The reflected signal from the zircaloy rods depends on the position of the assembly, but in all cases is easily discernable from the reference scan of background with no assembly

  14. Calibration-free quantitative elemental analysis of meteor plasma using reference laser-induced breakdown spectroscopy of meteorite samples

    Science.gov (United States)

    Ferus, Martin; Koukal, Jakub; Lenža, Libor; Srba, Jiří; Kubelík, Petr; Laitl, Vojtěch; Zanozina, Ekaterina M.; Váňa, Pavel; Kaiserová, Tereza; Knížek, Antonín; Rimmer, Paul; Chatzitheodoridis, Elias; Civiš, Svatopluk

    2018-03-01

    Aims: We aim to analyse real-time Perseid and Leonid meteor spectra using a novel calibration-free (CF) method, which is usually applied in the laboratory for laser-induced breakdown spectroscopic (LIBS) chemical analysis. Methods: Reference laser ablation spectra of specimens of chondritic meteorites were measured in situ simultaneously with a high-resolution laboratory echelle spectrograph and a spectral camera for meteor observation. Laboratory data were subsequently evaluated via the CF method and compared with real meteor emission spectra. Additionally, spectral features related to airglow plasma were compared with the spectra of laser-induced breakdown and electric discharge in the air. Results: We show that this method can be applied in the evaluation of meteor spectral data observed in real time. Specifically, CF analysis can be used to determine the chemical composition of meteor plasma, which, in the case of the Perseid and Leonid meteors analysed in this study, corresponds to that of the C-group of chondrites.

  15. Fiber laser front end for high energy petawatt laser systems

    International Nuclear Information System (INIS)

    Dawson, J W; Messerly, M J; Phan, H; Mitchell, S; Drobshoff, A; Beach, R J; Siders, C; Lucianetti, A; Crane, J K; Barty, C J

    2006-01-01

    We are developing a fiber laser front end suitable for high energy petawatt laser systems on large glass lasers such as NIF. The front end includes generation of the pulses in a fiber mode-locked oscillator, amplification and pulse cleaning, stretching of the pulses to >3ns, dispersion trimming, timing, fiber transport of the pulses to the main laser bay and amplification of the pulses to an injection energy of 150 (micro)J. We will discuss current status of our work including data from packaged components. Design detail such as how the system addresses pulse contrast, dispersion trimming and pulse width adjustment and impact of B-integral on the pulse amplification will be discussed. A schematic of the fiber laser system we are constructing is shown in figure 1 below. A 40MHz packaged mode-locked fiber oscillator produces ∼1nJ pulses which are phase locked to a 10MHz reference clock. These pulses are down selected to 100kHz and then amplified while still compressed. The amplified compressed pulses are sent through a non-linear polarization rotation based pulse cleaner to remove background amplified spontaneous emission (ASE). The pulses are then stretched by a chirped fiber Bragg grating (CFBG) and then sent through a splitter. The splitter splits the signal into two beams. (From this point we follow only one beam as the other follows an identical path.) The pulses are sent through a pulse tweaker that trims dispersion imbalances between the final large optics compressor and the CFBG. The pulse tweaker also permits the dispersion of the system to be adjusted for the purpose of controlling the final pulse width. Fine scale timing between the two beam lines can also be adjusted in the tweaker. A large mode area photonic crystal single polarization fiber is used to transport the pulses from the master oscillator room to the main laser bay. The pulses are then amplified a two stage fiber amplifier to 150mJ. These pulses are then launched into the main amplifier

  16. Test of an albedo neutron dosimetry system: TLD calibration and readout procedure, neutron calibration, dosimetry properties, routine application

    International Nuclear Information System (INIS)

    Piesch, E.; Burgkhardt, B.

    1988-03-01

    The two-component albedo dosemeter in use consists of an universal boron-loaded plastic encapsulation, the beta and albedo neutron windows of which are adopted to the corresponding TLD system of the manufacturers Alnor, Harshaw, Panasonic and Vinten. Beside the TLD detectors the capsule may contain also track etch detectors. Within a BMU project the system was investigated by four governmental measurement services in the FRG with respect to its qualification for personnel monitoring with emphasis in the readout and calibration procedures for the TLD system, the evaluation technique for the estimation of the photon and neutron dose equivalent in routine monitoring and the calibration of the personnel dosemeter in stray neutron fields. The test has shown the readiness of the system to act in the application areas of nuclear power reactors and linacs behind heavy shieldings, in the fuel element cycle, use of fissile materials, criticality, use of radionuclide sources, high energy particle accelerators. The uncertainty due to energy dependence was found to be within a factor of 2 for a single application area. In the case of irradiations from the front half space the dose equivalent H'(10) is indicated sufficiently independent of the direction of the radiation incidence. After completion of the test the albedo dosemeter became the official neutron personnel dosemeter in the FRG. It allows the separate estimation of the dose equivalent of hard beta radiation, photon radiation and neutrons. (orig./HP) [de

  17. Study on on-machine defects measuring system on high power laser optical elements

    Science.gov (United States)

    Luo, Chi; Shi, Feng; Lin, Zhifan; Zhang, Tong; Wang, Guilin

    2017-10-01

    The influence of surface defects on high power laser optical elements will cause some harm to the performances of imaging system, including the energy consumption and the damage of film layer. To further increase surface defects on high power laser optical element, on-machine defects measuring system was investigated. Firstly, the selection and design are completed by the working condition analysis of the on-machine defects detection system. By designing on processing algorithms to realize the classification recognition and evaluation of surface defects. The calibration experiment of the scratch was done by using the self-made standard alignment plate. Finally, the detection and evaluation of surface defects of large diameter semi-cylindrical silicon mirror are realized. The calibration results show that the size deviation is less than 4% that meet the precision requirement of the detection of the defects. Through the detection of images the on-machine defects detection system can realize the accurate identification of surface defects.

  18. Multi-element quantification of ancient/historic glasses by laser ablation inductively coupled plasma mass spectrometry using sum normalization calibration

    International Nuclear Information System (INIS)

    Elteren, Johannes T. van; Tennent, Norman H.; Selih, Vid S.

    2009-01-01

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for quantitative analysis of ancient/historic glasses is subject to calibration issues which have been addressed in this work. Since ancient/historic glasses have widely ranging matrix compositions, a complementary analysis by an alternative method is generally employed to determine at least one major element which can be used as an internal standard. We demonstrate that such a complementary analysis is unnecessary using a so-called sum normalization calibration technique (mathematically formulated) by simultaneous measurement of 54 elements and normalizing them to 100% [w/w] based on their corresponding oxide concentrations. The crux of this approach is that by assuming a random internal standard concentration of a particular major oxide, e.g. SiO 2 , the normalization algorithm varies the internal standard concentration until the cumulated concentrations of all 54 elemental oxides reach 100% [w/w]. The fact that 54 elements are measured simultaneously predetermines the laser ablation mode to rastering. Nine glass standards, some replicating historic compositions, were used for calibration. The linearity of the calibration graphs (forced through the origin) represented by the relative standard deviations in the slope were between 0.1 and 6.6% using SiO 2 as an internal standard. This allows high-accuracy determination of elemental oxides as confirmed by good agreement between found and reported values for major and minor elemental oxides in some synthetic glasses with typical medieval composition (European Science Foundation 151 and 158). Also for trace elemental concentrations of lanthanides in a reference glass (P and H Developments Ltd. DLH7, a base glass composition with nominally 75 μg g -1 elements added) accurate data were obtained. Interferences from polyatomic species and doubly charged species on the masses of trace elements are possible, depending on the base composition of the

  19. System for increasing laser pulse rate

    International Nuclear Information System (INIS)

    1980-01-01

    A technique of static elements is disclosed for combining a plurality of laser beams having time sequenced, pulsed radiation to achieve an augmented pulse rate. The technique may also be applied in a system for combining both time sequenced pulses and frequency distinct pulses for use in a system for isotope enrichment. (author)

  20. Correlation control theory of chaotic laser systems

    International Nuclear Information System (INIS)

    Li Fuli.

    1986-04-01

    A novel control theory of chaotic systems is studied. The correlation functions are calculated and used as feedback signals of the chaotic lasers. Computer experiments have shown that in this way the chaotic systems can be controlled to have time-independent output when the external control parameters are in chaotic domain. (author)

  1. Image digitizer system for bubble chamber laser

    International Nuclear Information System (INIS)

    Haggerty, H.

    1986-01-01

    An IBM PC-based image digitizer system has been assembled to monitor the laser flash used for holography at the 15 foot bubble chamber. The hardware and the operating software are outlined. For an operational test of the system, an array of LEDs was flashed with a 10 microsecond pulse and the image was grabbed by one of the operating programs and processed

  2. Control system for JAERI Free Electron Laser

    International Nuclear Information System (INIS)

    Sugimoto, Masayoshi

    1992-01-01

    A control system comprising of the personal computers network and the CAMAC stations for the JAERI Free Electron Laser is designed and is in the development stage. It controls the equipment and analyzes the electron and optical beam experiments. The concept and the prototype of the control system are described. (author)

  3. An accurate system for onsite calibration of electronic transformers with digital output

    International Nuclear Information System (INIS)

    Zhi Zhang; Li Hongbin

    2012-01-01

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  4. An accurate system for onsite calibration of electronic transformers with digital output.

    Science.gov (United States)

    Zhi, Zhang; Li, Hong-Bin

    2012-06-01

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  5. An accurate system for onsite calibration of electronic transformers with digital output

    Energy Technology Data Exchange (ETDEWEB)

    Zhi Zhang; Li Hongbin [CEEE of HuaZhong University of Science and Technology, Wuhan 430074 (China); State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Wuhan 430074 (China)

    2012-06-15

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  6. An accurate system for onsite calibration of electronic transformers with digital output

    Science.gov (United States)

    Zhi, Zhang; Li, Hong-Bin

    2012-06-01

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  7. EPMT: a portable transfer standard for telemetry system pressure-transducer calibration

    International Nuclear Information System (INIS)

    Hasbrouck, R.T.

    1977-01-01

    The LLL developed electronic pressure meter (EPMT) is a portable static-pressure calibration instrument for use with the LLL telemetry transducer system at the Nevada Test Site (NTS). It is significantly more accurate and rugged than the bourdon-tube pressure gauge it replaces, and can be incorporated into a field-use, semi-automatic, pressure calibration system. The process by which a transducer is selected for EPMT use from the inventory of field-service-certified transducers and subjected to an extensive preconditioning and calibration procedure is described. By combining this unusual calibration procedure with a unique, statistically based data-reduction routine, the total uncertainty of the measuring process at each calibration point can be determined with high accuracy

  8. A Printer Indexing System for Color Calibration with Applications in Dietary Assessment.

    Science.gov (United States)

    Fang, Shaobo; Liu, Chang; Zhu, Fengqing; Boushey, Carol; Delp, Edward

    2015-09-01

    In image based dietary assessment, color is a very important feature in food identification. One issue with using color in image analysis in the calibration of the color imaging capture system. In this paper we propose an indexing system for color camera calibration using printed color checkerboards also known as fiducial markers (FMs). To use the FM for color calibration one must know which printer was used to print the FM so that the correct color calibration matrix can be used for calibration. We have designed a printer indexing scheme that allows one to determine which printer was used to print the FM based on a unique arrangement of color squares and binarized marks (used for error control) printed on the FM. Using normalized cross correlation and pattern detection, the index corresponding to the printer for a particular FM can be determined. Our experimental results show this scheme is robust against most types of lighting conditions.

  9. PHASE NOISE COMPARISON OF SHORT PULSE LASER SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Shukui Zhang; Stephen Benson; John Hansknecht; David Hardy; George Neil; Michelle D. Shinn

    2006-08-27

    This paper describes phase noise measurements of several different laser systems that have completely different gain media and configurations including a multi-kW free-electron laser. We will focus on state-of-the-art short pulse lasers, especially drive lasers for photocathode injectors. Phase noise comparison of the FEL drive laser, electron beam and FEL laser output also will be presented.

  10. Dynamic Calibration and Verification Device of Measurement System for Dynamic Characteristic Coefficients of Sliding Bearing

    Science.gov (United States)

    Chen, Runlin; Wei, Yangyang; Shi, Zhaoyang; Yuan, Xiaoyang

    2016-01-01

    The identification accuracy of dynamic characteristics coefficients is difficult to guarantee because of the errors of the measurement system itself. A novel dynamic calibration method of measurement system for dynamic characteristics coefficients is proposed in this paper to eliminate the errors of the measurement system itself. Compared with the calibration method of suspension quality, this novel calibration method is different because the verification device is a spring-mass system, which can simulate the dynamic characteristics of sliding bearing. The verification device is built, and the calibration experiment is implemented in a wide frequency range, in which the bearing stiffness is simulated by the disc springs. The experimental results show that the amplitude errors of this measurement system are small in the frequency range of 10 Hz–100 Hz, and the phase errors increase along with the increasing of frequency. It is preliminarily verified by the simulated experiment of dynamic characteristics coefficients identification in the frequency range of 10 Hz–30 Hz that the calibration data in this frequency range can support the dynamic characteristics test of sliding bearing in this frequency range well. The bearing experiments in greater frequency ranges need higher manufacturing and installation precision of calibration device. Besides, the processes of calibration experiments should be improved. PMID:27483283

  11. The Construction and Calibration of a LADAR (Laser Detection and Ranging) Cross-Section Measurement Range

    Science.gov (United States)

    1985-12-01

    resonator optics consist of two porro prisms which are oriented 900 from one another about the cavity’s optical axis. In other words, the roof edges of each... prism are perpendicular to one another. The Nd:YAG laser rod measures 5 mm in diameter by 75 mm long and is optically pumped by a Xenon flashlamp. Q...Switching of the laser is performed by a Pockels Cell. A dielectric polarizer is sealed between two right angle prisms which are joined symetrically

  12. The Fiber Optic System for the Advanced Topographic Laser Altimeter System (ATLAS) Instrument

    Science.gov (United States)

    Ott, Melanie N.; Thomes, Joe; Onuma, Eleanya; Switzer, Robert; Chuska, Richard; Blair, Diana; Frese, Erich; Matyseck, Marc

    2016-01-01

    The Advanced Topographic Laser Altimeter System (ATLAS) Instrument has been in integration and testing over the past 18 months in preparation for the Ice, Cloud and Land Elevation Satellite - 2 (ICESat-2) Mission, scheduled to launch in 2017. ICESat-2 is the follow on to ICESat which launched in 2003 and operated until 2009. ATLAS will measure the elevation of ice sheets, glaciers and sea ice or the "cryosphere" (as well as terrain) to provide data for assessing the earth's global climate changes. Where ICESat's instrument, the Geo-Science Laser Altimeter (GLAS) used a single beam measured with a 70 m spot on the ground and a distance between spots of 170 m, ATLAS will measure a spot size of 10 m with a spacing of 70 cm using six beams to measure terrain height changes as small as 4 mm. The ATLAS pulsed transmission system consists of two lasers operating at 532 nm with transmitter optics for beam steering, a diffractive optical element that splits the signal into 6 separate beams, receivers for start pulse detection and a wavelength tracking system. The optical receiver telescope system consists of optics that focus all six beams into optical fibers that feed a filter system that transmits the signal via fiber assemblies to the detectors. Also included on the instrument is a system that calibrates the alignment of the transmitted pulses to the receiver optics for precise signal capture. The larger electro optical subsystems for transmission, calibration, and signal receive, stay aligned and transmitting sufficiently due to the optical fiber system that links them together. The robust design of the fiber optic system, consisting of a variety of multi fiber arrays and simplex assemblies with multiple fiber core sizes and types, will enable the system to maintain consistent critical alignments for the entire life of the mission. Some of the development approaches used to meet the challenging optical system requirements for ATLAS are discussed here.

  13. The fiber optic system for the Advanced Topographic Laser Altimeter System (ATLAS) instrument.

    Science.gov (United States)

    Ott, Melanie N; Thomes, Joe; Onuma, Eleanya; Switzer, Robert; Chuska, Richard; Blair, Diana; Frese, Erich; Matyseck, Marc

    2016-08-28

    The Advanced Topographic Laser Altimeter System (ATLAS) Instrument has been in integration and testing over the past 18 months in preparation for the Ice, Cloud and Land Elevation Satellite - 2 (ICESat-2) Mission, scheduled to launch in 2017. ICESat-2 is the follow on to ICESat which launched in 2003 and operated until 2009. ATLAS will measure the elevation of ice sheets, glaciers and sea ice or the "cryosphere" (as well as terrain) to provide data for assessing the earth's global climate changes. Where ICESat's instrument, the Geo-Science Laser Altimeter (GLAS) used a single beam measured with a 70 m spot on the ground and a distance between spots of 170 m, ATLAS will measure a spot size of 10 m with a spacing of 70 cm using six beams to measure terrain height changes as small as 4 mm.[1] The ATLAS pulsed transmission system consists of two lasers operating at 532 nm with transmitter optics for beam steering, a diffractive optical element that splits the signal into 6 separate beams, receivers for start pulse detection and a wavelength tracking system. The optical receiver telescope system consists of optics that focus all six beams into optical fibers that feed a filter system that transmits the signal via fiber assemblies to the detectors. Also included on the instrument is a system that calibrates the alignment of the transmitted pulses to the receiver optics for precise signal capture. The larger electro optical subsystems for transmission, calibration, and signal receive, stay aligned and transmitting sufficiently due to the optical fiber system that links them together. The robust design of the fiber optic system, consisting of a variety of multi fiber arrays and simplex assemblies with multiple fiber core sizes and types, will enable the system to maintain consistent critical alignments for the entire life of the mission. Some of the development approaches used to meet the challenging optical system requirements for ATLAS are discussed here.

  14. CONFOCAL MICROSCOPY SYSTEM PERFORMANCE: FOUNDATIONS FOR CALIBRATION, QUANTITATION AND SPECTROSCOPY

    Science.gov (United States)

    The confocal laser-scanning microscope (CLSM) has enormous potential in many biological fields. The goal of a CLSM is to acquire and quantify fluorescence and in some instruments acquire spectral characterization of emitted signals. The accuracy of these measurements demands that...

  15. Software System for the Calibration of X-Ray Measuring Instruments

    International Nuclear Information System (INIS)

    Gaytan-Gallardo, E.; Tovar-Munoz, V. M.; Cruz-Estrada, P.; Vergara-Martinez, F. J.; Rivero-Gutierrez, T.

    2006-01-01

    A software system that facilities the calibration of X-ray measuring instruments used in medical applications is presented. The Secondary Standard Dosimetry Laboratory (SSDL) of the Nuclear Research National Institute in Mexico (ININ in Spanish), supports activities concerning with ionizing radiations in medical area. One of these activities is the calibration of X-ray measuring instruments, in terms of air kerma or exposure by substitution method in an X-ray beam at a point where the rate has been determined by means of a standard ionization chamber. To automatize this process, a software system has been developed, the calibration system is composed by an X-ray unit, a Dynalizer IIIU X-ray meter by RADCAL, a commercial data acquisition card, the software system and the units to be tested and calibrated. A quality control plan has been applied in the development of the software system, ensuring that quality assurance procedures and standards are being followed

  16. Problems in the development of autonomous mobile laser systems based on a cw chemical DF laser

    International Nuclear Information System (INIS)

    Aleksandrov, B P; Bashkin, A S; Beznozdrev, V N; Parfen'ev, M V; Pirogov, N A; Semenov, S N

    2003-01-01

    The problems involved in designing autonomous mobile laser systems based on high-power cw chemical DF lasers, whose mass and size parameters would make it possible to install them on various vehicles, are discussed. The need for mobility of such lasers necessitates special attention to be paid to the quest for ways and means of reducing the mass and size of the main laser systems. The optimisation of the parameters of such lasers is studied for various methods of scaling their systems. A complex approach to analysis of the optical scheme of the laser system is developed. (special issue devoted to the 80th anniversary of academician n g basov's birth)

  17. The monitoring and calibration Web system of the ATLAS hadronic calorimeter

    International Nuclear Information System (INIS)

    Maidantchik, Carmen; Gomes, Andressa Andrea Sivollela; Marroquim, Fernando

    2011-01-01

    developed in collaboration with the TileCal and the UFRJ. MCWS provides the bad PMTs list and respective problems, which can have different reasons, such as signal transmission fault, defect on the channel power supply, laser calibration troubles, among other difficulties. MCWS supports the arduous analysis of the thousands electronic channels through the operation of simple functions in the interface. The system accesses the official ATLAS database and generates graphical results that are presented through the Web. The MCWS system also presents the TileCal general status as a reference to other ATLAS subdetectors. (author)

  18. The monitoring and calibration Web system of the ATLAS hadronic calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Maidantchik, Carmen; Gomes, Andressa Andrea Sivollela; Marroquim, Fernando [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)

    2011-07-01

    developed in collaboration with the TileCal and the UFRJ. MCWS provides the bad PMTs list and respective problems, which can have different reasons, such as signal transmission fault, defect on the channel power supply, laser calibration troubles, among other difficulties. MCWS supports the arduous analysis of the thousands electronic channels through the operation of simple functions in the interface. The system accesses the official ATLAS database and generates graphical results that are presented through the Web. The MCWS system also presents the TileCal general status as a reference to other ATLAS subdetectors. (author)

  19. A calibration-free ammonia breath sensor using a quantum cascade laser with WMS 2f/1f

    KAUST Repository

    Owen, Kyle

    2013-12-22

    The amount of ammonia in exhaled breath has been linked to a variety of adverse medical conditions, including chronic kidney disease (CKD). The development of accurate, reliable breath sensors has the potential to improve medical care. Wavelength modulation spectroscopy with second harmonic normalized by the first harmonic (WMS 2f/1f) is a sensitive technique used in the development of calibration-free sensors. An ammonia gas sensor is designed and developed that uses a quantum cascade laser operating near 1,103.44 cm -1 and a multi-pass cell with an effective path length of 76.45 m. The sensor has a 7 ppbv detection limit and 5 % total uncertainty for breath measurements. The sensor was successfully used to detect ammonia in exhaled breath and compare healthy patients to patients diagnosed with CKD. © 2013 Springer-Verlag Berlin Heidelberg.

  20. Vacuum mechatronic laser alignment system on the Nova laser

    International Nuclear Information System (INIS)

    Holliday, M.; Wong, K.; Shelton, R.

    1991-11-01

    The experiments conducted on NOVA are done to investigate inertially confined laser fusion reactions. To this end, the ten beams of the laser are aligned to within 30mm. The target chamber employs a vacuum mechatronic based reticle/target positioning system to accomplish this. It is a five degree-of-freedom chamber resident system, known as the Alignment Aids Positioner or AAP. The AAP aids in beam and diagnostic alignment by accurately positioning a reticle at target chamber center to with 7mm. The AAP system increases target positioning and alignment flexibility and accuracy through the use of a computer controlled multi degree-of-freedom stage assembly. This device uses microstepping DC stepper motors with encoders to achieve closed loop control in a 10 -6 torr vacuum. The AAP has two positioning regimes to move the alignment reticle and do beam alignment. One is course positioning in the Y-Z plane that moves a high resolution stage assembly to target chamber center. The other regime is high resolution movement in the X,Y,Z and q directions. 5 refs., 9 figs

  1. Laser-induced breakdown spectroscopy for space exploration applications: Influence of the ambient pressure on the calibration curves prepared from soil and clay samples

    International Nuclear Information System (INIS)

    Salle, Beatrice; Cremers, David A.; Maurice, Sylvestre; Wiens, Roger C.

    2005-01-01

    Recently, there has been an increasing interest in the laser-induced breakdown spectroscopy (LIBS) technique for stand-off detection of geological samples for use on landers and rovers to Mars, and for other space applications. For space missions, LIBS analysis capabilities must be investigated and instrumental development is required to take into account constraints such as size, weight, power and the effect of environmental atmosphere (pressure and ambient gas) on flight instrument performance. In this paper, we study the in-situ LIBS method at reduced pressure (7 Torr CO 2 to simulate the Martian atmosphere) and near vacuum (50 mTorr in air to begin to simulate the Moon or asteroids' pressure) as well as at atmospheric pressure in air (for Earth conditions and comparison). Here in-situ corresponds to distances on the order of 150 mm in contrast to stand-off analysis at distance of many meters. We show the influence of the ambient pressure on the calibration curves prepared from certified soil and clay pellets. In order to detect simultaneously all the elements commonly observed in terrestrial soils, we used an Echelle spectrograph. The results are discussed in terms of calibration curves, measurement precision, plasma light collection system efficiency and matrix effects

  2. Calibration of a flexible measurement system based on industrial articulated robot and structured light sensor

    Science.gov (United States)

    Mu, Nan; Wang, Kun; Xie, Zexiao; Ren, Ping

    2017-05-01

    To realize online rapid measurement for complex workpieces, a flexible measurement system based on an articulated industrial robot with a structured light sensor mounted on the end-effector is developed. A method for calibrating the system parameters is proposed in which the hand-eye transformation parameters and the robot kinematic parameters are synthesized in the calibration process. An initial hand-eye calibration is first performed using a standard sphere as the calibration target. By applying the modified complete and parametrically continuous method, we establish a synthesized kinematic model that combines the initial hand-eye transformation and distal link parameters as a whole with the sensor coordinate system as the tool frame. According to the synthesized kinematic model, an error model is constructed based on spheres' center-to-center distance errors. Consequently, the error model parameters can be identified in a calibration experiment using a three-standard-sphere target. Furthermore, the redundancy of error model parameters is eliminated to ensure the accuracy and robustness of the parameter identification. Calibration and measurement experiments are carried out based on an ER3A-C60 robot. The experimental results show that the proposed calibration method enjoys high measurement accuracy, and this efficient and flexible system is suitable for online measurement in industrial scenes.

  3. Camera Calibration of Stereo Photogrammetric System with One-Dimensional Optical Reference Bar

    International Nuclear Information System (INIS)

    Xu, Q Y; Ye, D; Che, R S; Qi, X; Huang, Y

    2006-01-01

    To carry out the precise measurement of large-scale complex workpieces, accurately calibration of the stereo photogrammetric system has becoming more and more important. This paper proposed a flexible and reliable camera calibration of stereo photogrammetric system based on quaternion with one-dimensional optical reference bar, which has three small collinear infrared LED marks and the lengths between these marks have been precisely calibration. By moving the optical reference bar at a number of locations/orientations over the measurement volume, we calibrate the stereo photogrammetric systems with the geometric constraint of the optical reference bar. The extrinsic parameters calibration process consists of linear parameters estimation based on quaternion and nonlinear refinement based on the maximum likelihood criterion. Firstly, we linear estimate the extrinsic parameters of the stereo photogrameetric systems based on quaternion. Then with the quaternion results as the initial values, we refine the extrinsic parameters through maximum likelihood criterion with the Levenberg-Marquardt Algorithm. In the calibration process, we can automatically control the light intensity and optimize the exposure time to get uniform intensity profile of the image points at different distance and obtain higher S/N ratio. The experiment result proves that the calibration method proposed is flexible, valid and obtains good results in the application

  4. Light scattering by ultrasonically-controlled small particles: system design, calibration, and measurement results

    Science.gov (United States)

    Kassamakov, Ivan; Maconi, Göran; Penttilä, Antti; Helander, Petteri; Gritsevich, Maria; Puranen, Tuomas; Salmi, Ari; Hæggström, Edward; Muinonen, Karri

    2018-02-01

    We present the design of a novel scatterometer for precise measurement of the angular Mueller matrix profile of a mm- to µm-sized sample held in place by sound. The scatterometer comprises a tunable multimode Argon-krypton laser (with possibility to set 1 of the 12 wavelengths in visible range), linear polarizers, a reference photomultiplier tube (PMT) for monitoring the beam intensity, and a micro-PMT module mounted radially towards the sample at an adjustable radius. The measurement angle is controlled by a motor-driven rotation stage with an accuracy of 15'. The system is fully automated using LabVIEW, including the FPGA-based data acquisition and the instrument's user interface. The calibration protocol ensures accurate measurements by using a control sphere sample (diameter 3 mm, refractive index of 1.5) fixed first on a static holder followed by accurate multi-wavelength measurements of the same sample levitated ultrasonically. To demonstrate performance of the scatterometer, we conducted detailed measurements of light scattered by a particle derived from the Chelyabinsk meteorite, as well as planetary analogue materials. The measurements are the first of this kind, since they are obtained using controlled spectral angular scattering including linear polarization effects, for arbitrary shaped objects. Thus, our novel approach permits a non-destructive, disturbance-free measurement with control of the orientation and location of the scattering object.

  5. Calibration of a TLD system to estimate personal doses in fields of gamma-neutrons radiation

    International Nuclear Information System (INIS)

    Villegas, E.N.; Somarriba, S.I.

    2016-01-01

    Currently Nicaragua has no personal neutron dosimetry system. The calibration of a batch of albedo neutron dosimeters consisting of two pairs of "6LiF and "7LiF (Mg, Ti) detectors was done. The dosimeter and reader sensitivities were obtained using a "1"3"7Cs source, and a neutron calibration factor was found with a "2"4"1AmBe source. Reproducibility and homogeneity tests were performed, and the detection limit of the system was determined. This calibration will allow the beginning of neutron personal monitoring in the country. (author)

  6. Alignment of the Measurement Scale Mark during Immersion Hydrometer Calibration Using an Image Processing System

    Directory of Open Access Journals (Sweden)

    Jose Emilio Vargas-Soto

    2013-10-01

    Full Text Available The present work presents an improved method to align the measurement scale mark in an immersion hydrometer calibration system of CENAM, the National Metrology Institute (NMI of Mexico, The proposed method uses a vision system to align the scale mark of the hydrometer to the surface of the liquid where it is immersed by implementing image processing algorithms. This approach reduces the variability in the apparent mass determination during the hydrostatic weighing in the calibration process, therefore decreasing the relative uncertainty of calibration.

  7. Alignment of the Measurement Scale Mark during Immersion Hydrometer Calibration Using an Image Processing System

    Science.gov (United States)

    Peña-Perez, Luis Manuel; Pedraza-Ortega, Jesus Carlos; Ramos-Arreguin, Juan Manuel; Arriaga, Saul Tovar; Fernandez, Marco Antonio Aceves; Becerra, Luis Omar; Hurtado, Efren Gorrostieta; Vargas-Soto, Jose Emilio

    2013-01-01

    The present work presents an improved method to align the measurement scale mark in an immersion hydrometer calibration system of CENAM, the National Metrology Institute (NMI) of Mexico, The proposed method uses a vision system to align the scale mark of the hydrometer to the surface of the liquid where it is immersed by implementing image processing algorithms. This approach reduces the variability in the apparent mass determination during the hydrostatic weighing in the calibration process, therefore decreasing the relative uncertainty of calibration. PMID:24284770

  8. Calibration and validation of a model describing complete autotrophic nitrogen removal in a granular SBR system

    DEFF Research Database (Denmark)

    Vangsgaard, Anna Katrine; Mutlu, Ayten Gizem; Gernaey, Krist

    2013-01-01

    BACKGROUND: A validated model describing the nitritation-anammox process in a granular sequencing batch reactor (SBR) system is an important tool for: a) design of future experiments and b) prediction of process performance during optimization, while applying process control, or during system scale......-up. RESULTS: A model was calibrated using a step-wise procedure customized for the specific needs of the system. The important steps in the procedure were initialization, steady-state and dynamic calibration, and validation. A fast and effective initialization approach was developed to approximate pseudo...... screening of the parameter space proposed by Sin et al. (2008) - to find the best fit of the model to dynamic data. Finally, the calibrated model was validated with an independent data set. CONCLUSION: The presented calibration procedure is the first customized procedure for this type of system...

  9. 3D-Calibration for IMU of the Strapdown Inertial Navigation Systems

    Directory of Open Access Journals (Sweden)

    Avrutov V.V.

    2017-01-01

    Full Text Available A new calibration method for Inertial Measurement Unit (IMU of Strapdown Iner-tial Navigation Systems was presented. IMU has been composed of accelerometers, gyroscopes and a circuit of signal processing. Normally, a rate transfer test and multi-position tests are us-ing for IMU calibration. The new calibration method is based on whole angle rotation or finite rotation. In fact it’s suggested to turn over IMU around three axes simultaneously. In order to solve the equation of calibration, it is necessary to provide an equality of a rank of basic matrix into degree of basic matrix. The results of simulated IMU data presented to demonstrate the performance of the new calibration method.

  10. Cryogenic thermometer calibration system using a helium cooling loop and a temperature controller [for LHC magnets

    CERN Document Server

    Chanzy, E; Thermeau, J P; Bühler, S; Joly, C; Casas-Cubillos, J; Balle, C

    1998-01-01

    The IPN-Orsay and CERN are designing in close collaboration a fully automated cryogenic thermometer calibration facility which will calibrate in 3 years 10,000 cryogenic thermometers required for the Large Hadron Collider (LHC) operation. A reduced-scale model of the calibration facility has been developed, which enables the calibration of ten thermometers by comparison with two rhodium-iron standard thermometers in the 1.8 K to 300 K temperature range under vacuum conditions. The particular design, based on a helium cooling loop and an electrical temperature controller, gives good dynamic performances. This paper describes the experimental set-up and the data acquisition system. Results of experimental runs are also presented along with the estimated global accuracy for the calibration. (3 refs).

  11. Determination of Stark parameters by cross-calibration in a multi-element laser-induced plasma

    Science.gov (United States)

    Liu, Hao; Truscott, Benjamin S.; Ashfold, Michael N. R.

    2016-05-01

    We illustrate a Stark broadening analysis of the electron density Ne and temperature Te in a laser-induced plasma (LIP), using a model free of assumptions regarding local thermodynamic equilibrium (LTE). The method relies on Stark parameters determined also without assuming LTE, which are often unknown and unavailable in the literature. Here, we demonstrate that the necessary values can be obtained in situ by cross-calibration between the spectral lines of different charge states, and even different elements, given determinations of Ne and Te based on appropriate parameters for at least one observed transition. This approach enables essentially free choice between species on which to base the analysis, extending the range over which these properties can be measured and giving improved access to low-density plasmas out of LTE. Because of the availability of suitable tabulated values for several charge states of both Si and C, the example of a SiC LIP is taken to illustrate the consistency and accuracy of the procedure. The cross-calibrated Stark parameters are at least as reliable as values obtained by other means, offering a straightforward route to extending the literature in this area.

  12. Design and Realization of a Radon Gas Calibration System

    International Nuclear Information System (INIS)

    Boussek, Amal

    2013-01-01

    Our project consists on the automatization of a Radon calibration room. The first step was the development of several electronic cards collecting outside data coming to our device (pressure and temperature). Using ISIS software, we have designed these electronic cards: pressure, temperature, power supply, PIC interface and control card. In the second part, we have programmed the PIC 16F877 using the PCW compiler to display data on an LCD screen and sent them through the RS232 serial to the hyper-terminal and to control the motor and the fan. The last part aims to develop an interface using LabVIEW to command our device.

  13. Alignment of the Measurement Scale Mark during Immersion Hydrometer Calibration Using an Image Processing System

    OpenAIRE

    Pe?a-Perez, Luis Manuel; Pedraza-Ortega, Jesus Carlos; Ramos-Arreguin, Juan Manuel; Arriaga, Saul Tovar; Fernandez, Marco Antonio Aceves; Becerra, Luis Omar; Hurtado, Efren Gorrostieta; Vargas-Soto, Jose Emilio

    2013-01-01

    The present work presents an improved method to align the measurement scale mark in an immersion hydrometer calibration system of CENAM, the National Metrology Institute (NMI) of Mexico, The proposed method uses a vision system to align the scale mark of the hydrometer to the surface of the liquid where it is immersed by implementing image processing algorithms. This approach reduces the variability in the apparent mass determination during the hydrostatic weighing in the calibration process,...

  14. A NEW AUTOMATIC SYSTEM CALIBRATION OF MULTI-CAMERAS AND LIDAR SENSORS

    Directory of Open Access Journals (Sweden)

    M. Hassanein

    2016-06-01

    Full Text Available In the last few years, multi-cameras and LIDAR systems draw the attention of the mapping community. They have been deployed on different mobile mapping platforms. The different uses of these platforms, especially the UAVs, offered new applications and developments which require fast and accurate results. The successful calibration of such systems is a key factor to achieve accurate results and for the successful processing of the system measurements especially with the different types of measurements provided by the LIDAR and the cameras. The system calibration aims to estimate the geometric relationships between the different system components. A number of applications require the systems be ready for operation in a short time especially for disasters monitoring applications. Also, many of the present system calibration techniques are constrained with the need of special arrangements in labs for the calibration procedures. In this paper, a new technique for calibration of integrated LIDAR and multi-cameras systems is presented. The new proposed technique offers a calibration solution that overcomes the need for special labs for standard calibration procedures. In the proposed technique, 3D reconstruction of automatically detected and matched image points is used to generate a sparse images-driven point cloud then, a registration between the LIDAR generated 3D point cloud and the images-driven 3D point takes place to estimate the geometric relationships between the cameras and the LIDAR.. In the presented technique a simple 3D artificial target is used to simplify the lab requirements for the calibration procedure. The used target is composed of three intersected plates. The choice of such target geometry was to ensure enough conditions for the convergence of registration between the constructed 3D point clouds from the two systems. The achieved results of the proposed approach prove its ability to provide an adequate and fully automated

  15. Laser fusion system design study. Final report

    International Nuclear Information System (INIS)

    1975-01-01

    The following studies were completed: (1) The synthesis of a pointing/control system compatible with existing and advanced laser opto-mechanical configurations. (2) Attainment of the required pointing angle, longitudinal focus, and differential pathlength accuracies. (3) Maximum modularization of the sensor and gimbal assemblies to provide the required accuracies at minimum cost. Detailed information is given on each. (MOW)

  16. Electronic Subsystems For Laser Communication System

    Science.gov (United States)

    Long, Catherine; Maruschak, John; Patschke, Robert; Powers, Michael

    1992-01-01

    Electronic subsystems of free-space laser communication system carry digital signals at 650 Mb/s over long distances. Applicable to general optical communications involving transfer of great quantities of data, and transmission and reception of video images of high definition.

  17. MBE System for Antimonide Based Semiconductor Lasers

    National Research Council Canada - National Science Library

    Lester, Luke

    1999-01-01

    .... SLR-770 inductively coupled plasma (ICP) processing system. The SLR-770 has been invaluable in the study of plasma etching of AlGaAsSb and GaSb-materials that form the backbone of antimonide-based semiconductor lasers...

  18. Construction of a test cell for the laser calibration of the planar ZEUS drift chambers and studies of algorithms for the analysis of FADC signals

    International Nuclear Information System (INIS)

    Dabbous, H.

    1988-07-01

    The planar drift chambers (FTD 1, 2, 3) of the ZEUS forward detector (FDET) will be operated in an inhomogeneous part of the magnetic field produced by the ZEUS solenoid. The calibration of the drift chambers will therefore be performed by measuring the space-drift-time-relation in a small test cell for a variety of combinations of anti E and anti B. This will be done by means of an UV-laser. The test cell is designed to be rotated around 2 axes in the homogeneous anti B-field of a large magnet available at DESY. The laser beam enters the test cell through a quartz window and is appropriately deflected by a system of 3 mirrors. In the second part of this paper several algorithms for the analysis of FADC signals are investigated, in view of optimal spatial and double track resolution. The best results have been obtained with a newly developed method based on digital filtering. (orig.) [de

  19. Determination of plasma temperature and electron density in river sediment plasma using calibration-free laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Austria, Elmer S. Jr.; Lamorena-Lim, Rheo B.

    2015-01-01

    Calibration-free laser-induced breakdown spectroscopy (CF-LIBS) technique is an approach used to quantitatively measure elemental composition of samples without the use of standard reference materials (SRMs). Due to the unavailability of most SRMs for specific samples, the CF-LIBS approach is steadily becoming more prevalent. CF-LIBS also minimizes interferences from the sample matrix by accounting spectral line intensifies of different elements. The first part of the CF-LIBS algorithm is the calculation of plasma temperature and electron density of the sample while the second part deals with the self-absorption correction and quantitative elemental analysis. In this study, the precursor parameters for the algorithm - plasma temperature and electron density - were measured through the neutral atom and ion line emissions of Fe and Cu in the time window of 0.1 to 10 μs. Plasma from river sediment samples were produced by a 1064 nm nanosecond pulsed Nd:YAG laser at atmospheric pressure. The plasma temperature and electron density were calculated from the Boltzmann plot and Saha-Boltzmann equation methods, respectively. These precursor parameters can be used in calculating the time window wherein the plasma is optically thin at local thermodynamic equilibrium (LTE) and for quantitative multi-elemental analysis. (author)

  20. Calibration factor or calibration coefficient?

    International Nuclear Information System (INIS)

    Meghzifene, A.; Shortt, K.R.

    2002-01-01

    Full text: The IAEA/WHO network of SSDLs was set up in order to establish links between SSDL members and the international measurement system. At the end of 2001, there were 73 network members in 63 Member States. The SSDL network members provide calibration services to end-users at the national or regional level. The results of the calibrations are summarized in a document called calibration report or calibration certificate. The IAEA has been using the term calibration certificate and will continue using the same terminology. The most important information in a calibration certificate is a list of calibration factors and their related uncertainties that apply to the calibrated instrument for the well-defined irradiation and ambient conditions. The IAEA has recently decided to change the term calibration factor to calibration coefficient, to be fully in line with ISO [ISO 31-0], which recommends the use of the term coefficient when it links two quantities A and B (equation 1) that have different dimensions. The term factor should only be used for k when it is used to link the terms A and B that have the same dimensions A=k.B. However, in a typical calibration, an ion chamber is calibrated in terms of a physical quantity such as air kerma, dose to water, ambient dose equivalent, etc. If the chamber is calibrated together with its electrometer, then the calibration refers to the physical quantity to be measured per electrometer unit reading. In this case, the terms referred have different dimensions. The adoption by the Agency of the term coefficient to express the results of calibrations is consistent with the 'International vocabulary of basic and general terms in metrology' prepared jointly by the BIPM, IEC, ISO, OIML and other organizations. The BIPM has changed from factor to coefficient. The authors believe that this is more than just a matter of semantics and recommend that the SSDL network members adopt this change in terminology. (author)

  1. Infrared laser scattering system for the plasma diagnostics

    International Nuclear Information System (INIS)

    Hiraki, Naoji; Kawasaki, Shoji; Muraoka, Katsunori

    1975-01-01

    As the results of the parametric studies of the double discharge TEA CO 2 laser, the required properties on the laser system for the scattering diagnostics of plasmas are shown to be realized with our CO 2 laser. The direction of the future improvements of the laser performance is also discussed. (auth.)

  2. Five Wavelength DFB Fibre Laser Source for WDM Systems

    DEFF Research Database (Denmark)

    Hübner, Jörg; Varming, Poul; Kristensen, Martin

    1997-01-01

    Singlemode UV-induced distributed feedback (DFB) fibre lasers with a linewidth of lasers is verified by a 10 Gbit/s transmission experiment. Five DFB fibre lasers are cascaded and pumped by a single...... semiconductor laser, thereby forming a multiwavelength source for WDM systems...

  3. Calibration of an arbitrarily arranged projection moiré system for 3D shape measurement

    Science.gov (United States)

    Tang, Ying; Yao, Jun; Zhou, Yihao; Sun, Chen; Yang, Peng; Miao, Hong; Chen, Jubing

    2018-05-01

    An arbitrarily arranged projection moiré system is presented for three-dimensional shape measurement. We develop a model for projection moiré system and derive a universal formula expressing the relation between height and phase variation before and after we put the object on the reference plane. With so many system parameters involved, a system calibration technique is needed. In this work, we provide a robust and accurate calibration method for an arbitrarily arranged projection moiré system. The system no longer puts restrictions on the configuration of the optical setup. Real experiments have been conducted to verify the validity of this method.

  4. Calibration of new measuring systems to detect emissions of radioactive noble gases

    International Nuclear Information System (INIS)

    Winkelmann, I.; Kreiner, H.J.

    1977-12-01

    This report describes the calibration of different systems for the integral measurement of radioactive noble gases and the calibration of a measuring chamber for the detection of individual nuclides of radioactive noble gases in the gaseous effluent of nuclear power plants. For these measuring chambers the calibration factors for Kr-85 and Xe-133 are given as well as the detection limits to be obtained with these measuring systems for several radioactive noble gases present in the gaseous effluent at the stack of nuclear power plants. Calibration factors for Kr-85 and Xe-133 and the detection limits of this measuring method for the detections of individual nuclides of radioactive noble gases in air samples are defined taken wirh a high pressure compressor in pressure flasks an measured on a Ge(Li)-semiconductor spectrometer (pressure flask measuring method). A measuring equipment is described and calibrated which allows simultaneous measurement of activity concentration of radioactive noble gases and radioactive aerosols with a sensitivity of 2 x 10 -7 Ci/m 3 for radioactive gases and 1 x 10 -9 Ci/m 3 for radioactive particulates at a background radiation of 1 R/h. This paper is an additional report to our STH-Bericht 3/76, 'Calibration of measuring equipment for monitoring of gaseous effluents from nuclear power plants', which specifies a procedure for the calibration of measuring chambers for monitoring of gaseous radioactive effluents from nuclear power plants /1/. The calibration system used here makes it possible to simultaneously calibrate several noble gas measuring devices. (orig.) [de

  5. Data processing and in-flight calibration systems for OMI-EOS-Aura

    Science.gov (United States)

    van den Oord, G. H. J.; Dobber, M.; van de Vegte, J.; van der Neut, I.; Som de Cerff, W.; Rozemeijer, N. C.; Schenkelaars, V.; ter Linden, M.

    2006-08-01

    The OMI instrument that flies on the EOS Aura mission was launched in July 2004. OMI is a UV-VIS imaging spectrometer that measures in the 270 - 500 nm wavelength range. OMI provides daily global coverage with high spatial resolution. Every orbit of 100 minutes OMI generates about 0.5 GB of Level 0 data and 1.2 GB of Level 1 data. About half of the Level 1 data consists of in-flight calibration measurements. These data rates make it necessary to automate the process of in-flight calibration. For that purpose two facilities have been developed at KNMI in the Netherlands: the OMI Dutch Processing System (ODPS) and the Trend Monitoring and In-flight Calibration Facility (TMCF). A description of these systems is provided with emphasis on the use for radiometric, spectral and detector calibration and characterization. With the advance of detector technology and the need for higher spatial resolution, data rates will become even higher for future missions. To make effective use of automated systems like the TMCF, it is of paramount importance to integrate the instrument operations concept, the information contained in the Level 1 (meta-)data products and the inflight calibration software and system databases. In this way a robust but also flexible end-to-end system can be developed that serves the needs of the calibration staff, the scientific data users and the processing staff. The way this has been implemented for OMI may serve as an example of a cost-effective and user friendly solution for future missions. The basic system requirements for in-flight calibration are discussed and examples are given how these requirements have been implemented for OMI. Special attention is paid to the aspect of supporting the Level 0 - 1 processing with timely and accurate calibration constants.

  6. An accurate on-site calibration system for electronic voltage transformers using a standard capacitor

    Science.gov (United States)

    Hu, Chen; Chen, Mian-zhou; Li, Hong-bin; Zhang, Zhu; Jiao, Yang; Shao, Haiming

    2018-05-01

    Ordinarily electronic voltage transformers (EVTs) are calibrated off-line and the calibration procedure requires complex switching operations, which will influence the reliability of the power grid and induce large economic losses. To overcome this problem, this paper investigates a 110 kV on-site calibration system for EVTs, including a standard channel, a calibrated channel and a PC equipped with the LabView environment. The standard channel employs a standard capacitor and an analogue integrating circuit to reconstruct the primary voltage signal. Moreover, an adaptive full-phase discrete Fourier transform (DFT) algorithm is proposed to extract electrical parameters. The algorithm involves the process of extracting the frequency of the grid, adjusting the operation points, and calculating the results using DFT. In addition, an insulated automatic lifting device is designed to realize the live connection of the standard capacitor, which is driven by a wireless remote controller. A performance test of the capacitor verifies the accurateness of the standard capacitor. A system calibration test shows that the system ratio error is less than 0.04% and the phase error is below 2‧, which meets the requirement of the 0.2 accuracy class. Finally, the developed calibration system was used in a substation, and the field test data validates the availability of the system.

  7. Evolution of shiva laser alignment systems

    International Nuclear Information System (INIS)

    Boyd, R.D.

    1980-07-01

    The Shiva oscillator pulse is preamplified and divided into twenty beams. Each beam is then amplified, spatially filtered, directed, and focused onto a target a few hundred micrometers in size producing optical intensities up to 10 16 W/cm 2 . The laser was designed and built with three automatic alignment systems: the oscillator alignment system, which aligns each of the laser's three oscillators to a reference beamline; the chain input pointing system, which points each beam into its respective chain; and the chain output pointing, focusing and centering system which points, centers and focuses the beam onto the target. Recently the alignment of the laser's one hundred twenty spatial filter pinholes was also automated. This system uses digitized video images of back-illuminated pinholes and computer analysis to determine current positions. The offset of each current position from a desired center point is then translated into stepper motor commands and the pinhole is moved the proper distance. While motors for one pinhole are moving, the system can digitize, analyze, and send commands to other motors, allowing the system to efficiently align several pinholes in parallel

  8. Embedded calibration system for the DIII-D Langmuir probe analog fiber optic links

    International Nuclear Information System (INIS)

    Watkins, J. G.; Rajpal, R.; Mandaliya, H.; Watkins, M.; Boivin, R. L.

    2012-01-01

    This paper describes a generally applicable technique for simultaneously measuring offset and gain of 64 analog fiber optic data links used for the DIII-D fixed Langmuir probes by embedding a reference voltage waveform in the optical transmitted signal before every tokamak shot. The calibrated data channels allow calibration of the power supply control fiber optic links as well. The array of fiber optic links and the embedded calibration system described here makes possible the use of superior modern data acquisition electronics in the control room.

  9. Dosimetric survey in industrial irradiators and dosimetric systems calibration

    International Nuclear Information System (INIS)

    Grossi, Pablo Andrade; Correa, Ricardo Ferracini; Oliveira, Paulo Marcio C. de

    2005-01-01

    The work seeks the collecting of dose rate points for irradiation research plants and calibration of commercial dosimeters, using dosimeters standard references. Using the obtained data is possible to determine the absorbed doses in any point of an irradiation room, assuring the value of absorbed dose in the irradiated product, with the use of the commercial dosimeters. The commercial dosimeters used in this work are polymethylmethacrylate (PMMA), and the reference dosimeters used are Fricke's solution. Among the advantages of the accomplishment of this work, it can stand out the quality assurance of the services rendered by Centro de Desenvolvimento da Tecnologia Nuclear to their customers and to the society, in the purpose of optimization of exposition time of the irradiated products, in way to guarantee the absorbed doses in each irradiated material with a good precision

  10. Amplitude variation in calibrated audiometer systems in Clinical Simulations

    Directory of Open Access Journals (Sweden)

    Christopher Barlow

    2014-01-01

    Full Text Available Manual pure tone audiometry is considered to be the gold standard for the assessment of hearing thresholds and has been in consistent use for a long period of time. An increased legislative requirement to monitor and screen workers, and an increasing amount of legislation relating to hearing loss is putting greater reliance on this as a tool. There are a number of questions regarding the degree of accuracy of pure tone audiometry when undertaken in field conditions, particularly relating to the difference in conditions between laboratory calibration and clinical or industrial screening use. This study analyzed the output sound pressure level of four different commercial audiometers, all using TDH39 headphones and each of which had recently undergone calibration at an appropriate laboratory. Levels were measured using a Bruël and Kjaer Head and Torso simulator, which accurately replicates the size and shape of a human head, including the ears. A clinical environment was simulated by a trained audiometrist replacing the headphones for each test. Tests were undertaken at three presentation levels, and at the frequencies of 250 Hz, 500 Hz, 1 kHz, 2 kHz, 4 kHz and 6 kHz. The results showed a high level of test-retest variability, both between different audiometers and within the same audiometer. Maximum variation of sound pressure level at the ear for the same tone presentation was 21 decibels, with a particularly high level of variation at 6 kHz for all meters. An audiometer with attenuating cups exhibited significantly higher variation than ones using supral-aural headphones. Overall the variation exhibited suggests that there is a higher degree of potential error with screening pure tone audiometry than is commonly assumed and that results particularly at the 6 kHz frequency need to be assessed carefully alongside other methods such as speech audiometry.

  11. Recent laser experiments on the Aurora KrF/ICF laser system

    International Nuclear Information System (INIS)

    Turner, T.P.; Jones, J.E.; Czuchlewski, S.J.; Watt, R.G.; Thomas, S.J.; Kang, M.; Tallman, C.R.; Mack, J.M.; Figueira, J.F.

    1990-01-01

    The Aurora KrF/ICF Laser Facility at Los Alamos is operational at the kilojoule-level for both laser and target experiments. We report on recent laser experiments on the system and resulting system improvements. 3 refs., 4 figs

  12. Multi-Sensor Calibration of Low-Cost Magnetic, Angular Rate and Gravity Systems

    Directory of Open Access Journals (Sweden)

    Markus Lüken

    2015-10-01

    Full Text Available We present a new calibration procedure for low-cost nine degrees-of-freedom (9DOF magnetic, angular rate and gravity (MARG sensor systems, which relies on a calibration cube, a reference table and a body sensor network (BSN. The 9DOF MARG sensor is part of our recently-developed “Integrated Posture and Activity Network by Medit Aachen” (IPANEMA BSN. The advantage of this new approach is the use of the calibration cube, which allows for easy integration of two sensor nodes of the IPANEMA BSN. One 9DOF MARG sensor node is thereby used for calibration; the second 9DOF MARG sensor node is used for reference measurements. A novel algorithm uses these measurements to further improve the performance of the calibration procedure by processing arbitrarily-executed motions. In addition, the calibration routine can be used in an alignment procedure to minimize errors in the orientation between the 9DOF MARG sensor system and a motion capture inertial reference system. A two-stage experimental study is conducted to underline the performance of our calibration procedure. In both stages of the proposed calibration procedure, the BSN data, as well as reference tracking data are recorded. In the first stage, the mean values of all sensor outputs are determined as the absolute measurement offset to minimize integration errors in the derived movement model of the corresponding body segment. The second stage deals with the dynamic characteristics of the measurement system where the dynamic deviation of the sensor output compared to a reference system is Sensors 2015, 15 25920 corrected. In practical validation experiments, this procedure showed promising results with a maximum RMS error of 3.89°.

  13. Multi-sensor calibration of low-cost magnetic, angular rate and gravity systems.

    Science.gov (United States)

    Lüken, Markus; Misgeld, Berno J E; Rüschen, Daniel; Leonhardt, Steffen

    2015-10-13

    We present a new calibration procedure for low-cost nine degrees-of-freedom (9DOF) magnetic, angular rate and gravity (MARG) sensor systems, which relies on a calibration cube, a reference table and a body sensor network (BSN). The 9DOF MARG sensor is part of our recently-developed "Integrated Posture and Activity Network by Medit Aachen" (IPANEMA) BSN. The advantage of this new approach is the use of the calibration cube, which allows for easy integration of two sensor nodes of the IPANEMA BSN. One 9DOF MARG sensor node is thereby used for calibration; the second 9DOF MARG sensor node is used for reference measurements. A novel algorithm uses these measurements to further improve the performance of the calibration procedure by processing arbitrarily-executed motions. In addition, the calibration routine can be used in an alignment procedure to minimize errors in the orientation between the 9DOF MARG sensor system and a motion capture inertial reference system. A two-stage experimental study is conducted to underline the performance of our calibration procedure. In both stages of the proposed calibration procedure, the BSN data, as well as reference tracking data are recorded. In the first stage, the mean values of all sensor outputs are determined as the absolute measurement offset to minimize integration errors in the derived movement model of the corresponding body segment. The second stage deals with the dynamic characteristics of the measurement system where the dynamic deviation of the sensor output compared to a reference system is Sensors 2015, 15 25920 corrected. In practical validation experiments, this procedure showed promising results with a maximum RMS error of 3.89°.

  14. A comparative study of laser induced breakdown spectroscopy analysis for element concentrations in aluminum alloy using artificial neural networks and calibration methods

    International Nuclear Information System (INIS)

    Inakollu, Prasanthi; Philip, Thomas; Rai, Awadhesh K.; Yueh Fangyu; Singh, Jagdish P.

    2009-01-01

    A comparative study of analysis methods (traditional calibration method and artificial neural networks (ANN) prediction method) for laser induced breakdown spectroscopy (LIBS) data of different Al alloy samples was performed. In the calibration method, the intensity of the analyte lines obtained from different samples are plotted against their concentration to form calibration curves for different elements from which the concentrations of unknown elements were deduced by comparing its LIBS signal with the calibration curves. Using ANN, an artificial neural network model is trained with a set of input data of known composition samples. The trained neural network is then used to predict the elemental concentration from the test spectra. The present results reveal that artificial neural networks are capable of predicting values better than traditional method in most cases

  15. Misalignment calibration of geomagnetic vector measurement system using parallelepiped frame rotation method

    International Nuclear Information System (INIS)

    Pang, Hongfeng; Zhu, XueJun; Pan, Mengchun; Zhang, Qi; Wan, Chengbiao; Luo, Shitu; Chen, Dixiang; Chen, Jinfei; Li, Ji; Lv, Yunxiao

    2016-01-01

    Misalignment error is one key factor influencing the measurement accuracy of geomagnetic vector measurement system, which should be calibrated with the difficulties that sensors measure different physical information and coordinates are invisible. A new misalignment calibration method by rotating a parallelepiped frame is proposed. Simulation and experiment result show the effectiveness of calibration method. The experimental system mainly contains DM-050 three-axis fluxgate magnetometer, INS (inertia navigation system), aluminium parallelepiped frame, aluminium plane base. Misalignment angles are calculated by measured data of magnetometer and INS after rotating the aluminium parallelepiped frame on aluminium plane base. After calibration, RMS error of geomagnetic north, vertical and east are reduced from 349.441 nT, 392.530 nT and 562.316 nT to 40.130 nT, 91.586 nT and 141.989 nT respectively. - Highlights: • A new misalignment calibration method by rotating a parallelepiped frame is proposed. • It does not need to know sensor attitude information or local dip angle. • The calibration system attitude change angle is not strictly required. • It can be widely used when sensors measure different physical information. • Geomagnetic vector measurement error is reduced evidently.

  16. Misalignment calibration of geomagnetic vector measurement system using parallelepiped frame rotation method

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Hongfeng [Academy of Equipment, Beijing 101416 (China); College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073 (China); Zhu, XueJun, E-mail: zhuxuejun1990@126.com [College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073 (China); Pan, Mengchun; Zhang, Qi; Wan, Chengbiao; Luo, Shitu; Chen, Dixiang; Chen, Jinfei; Li, Ji; Lv, Yunxiao [College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073 (China)

    2016-12-01

    Misalignment error is one key factor influencing the measurement accuracy of geomagnetic vector measurement system, which should be calibrated with the difficulties that sensors measure different physical information and coordinates are invisible. A new misalignment calibration method by rotating a parallelepiped frame is proposed. Simulation and experiment result show the effectiveness of calibration method. The experimental system mainly contains DM-050 three-axis fluxgate magnetometer, INS (inertia navigation system), aluminium parallelepiped frame, aluminium plane base. Misalignment angles are calculated by measured data of magnetometer and INS after rotating the aluminium parallelepiped frame on aluminium plane base. After calibration, RMS error of geomagnetic north, vertical and east are reduced from 349.441 nT, 392.530 nT and 562.316 nT to 40.130 nT, 91.586 nT and 141.989 nT respectively. - Highlights: • A new misalignment calibration method by rotating a parallelepiped frame is proposed. • It does not need to know sensor attitude information or local dip angle. • The calibration system attitude change angle is not strictly required. • It can be widely used when sensors measure different physical information. • Geomagnetic vector measurement error is reduced evidently.

  17. Practical use of control rod calibration system with the inverse kinetics method

    International Nuclear Information System (INIS)

    Yamanaka, Haruhiko; Hayashi, Kazuhiko; Motohashi, Jun; Kawashima, Kazuhito; Ichimura, Toshiyuki; Tamai, Kazuo; Takeuti, Mitsuo

    2002-01-01

    The control rod calibration results in the JRR-3 are used as a reactivity standard to measure and manage the reactivity change in the core. The total travel of all six control rods has been calibrated by an inverse kinetics method (IK method) during an annual maintenance period. The IK method has the great merit in saving measuring time compared with the conventional positive period method (PP method). The JRR-3 control rod calibration system was renovated and put into practical use in order to improve reliability and function by accumulating 10-year experience with the IK method in the JRR-3. The report shows the function, the performance and results of verification of the JRR-3 control rod calibration system. (author)

  18. Preliminary measurements of the establishment of a quality control programme for the activimeter calibration reference system

    International Nuclear Information System (INIS)

    Martins, Elaine W.; Potiens, Maria da Penha A.

    2009-01-01

    The nuclear medicine techniques efficiency and safety depends on, beside other factors, a quality control programme, mainly regards to the nuclides activimeter utilization. The Calibration Laboratory of IPEN uses as a work standard, a tertiary standard system Capintec, calibrated at the Accredited Dosimetry Calibration Laboratory of the Medical radiation Research Center - University of Wisconsin. In this work, as preliminary measurements to establish a quality control programme for the activimeter calibration procedures, initially the repeatability and reproducibility (long term stability) tests were performed using a sealed check source of 133 Ba. Later on, to complete this quality control programme other check sources ( 137 Cs, 57 Co, 60 Co) will be used to perform the same tests. A series of 80 experiments of 10 measurements each has been carried out. The reference system showed a good behaviour to the repeatability test, considering the tolerance limits of 5%. The percent deviations of all tested sources in the activity measurements were lower 1% to 133 Ba. (author)

  19. Laser Safety and Hazard Analysis for the Trailer (B70) Based AURA Laser System

    International Nuclear Information System (INIS)

    AUGUSTONI, ARNOLD L.

    2003-01-01

    A laser safety and hazard analysis was performed for the AURA laser system based on the 2000 version of the American National Standards Institute's (ANSI) Standard Z136.1, for ''Safe Use of Lasers'' and the 2000 version of the ANSI Standard Z136.6, for ''Safe Use of Lasers Outdoors''. The trailer based AURA laser system is a mobile platform, which is used to perform laser interaction experiments and tests at various national test sites. The trailer (B70) based AURA laser system is generally operated on the United State Air Force Starfire Optical Range (SOR) at Kirtland Air Force Base (KAFB), New Mexico. The laser is used to perform laser interaction testing inside the laser trailer as well as outside the trailer at target sites located at various distances from the exit telescope. In order to protect personnel, who work inside the Nominal Hazard Zone (NHZ), from hazardous laser emission exposures it was necessary to determine the Maximum Permissible Exposure (MPE) for each laser wavelength (wavelength bands) and calculate the appropriate minimum Optical Density (OD min ) of the laser safety eyewear used by authorized personnel and the Nominal Ocular Hazard Distance (NOHD) to protect unauthorized personnel who may have violated the boundaries of the control area and enter into the laser's NHZ

  20. 21 CFR 884.6200 - Assisted reproduction laser system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Assisted reproduction laser system. 884.6200... (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6200 Assisted reproduction laser system. (a) Identification. The assisted reproduction laser system is a device...

  1. Accurate technique for complete geometric calibration of cone-beam computed tomography systems

    International Nuclear Information System (INIS)

    Cho Youngbin; Moseley, Douglas J.; Siewerdsen, Jeffrey H.; Jaffray, David A.

    2005-01-01

    Cone-beam computed tomography systems have been developed to provide in situ imaging for the purpose of guiding radiation therapy. Clinical systems have been constructed using this approach, a clinical linear accelerator (Elekta Synergy RP) and an iso-centric C-arm. Geometric calibration involves the estimation of a set of parameters that describes the geometry of such systems, and is essential for accurate image reconstruction. We have developed a general analytic algorithm and corresponding calibration phantom for estimating these geometric parameters in cone-beam computed tomography (CT) systems. The performance of the calibration algorithm is evaluated and its application is discussed. The algorithm makes use of a calibration phantom to estimate the geometric parameters of the system. The phantom consists of 24 steel ball bearings (BBs) in a known geometry. Twelve BBs are spaced evenly at 30 deg in two plane-parallel circles separated by a given distance along the tube axis. The detector (e.g., a flat panel detector) is assumed to have no spatial distortion. The method estimates geometric parameters including the position of the x-ray source, position, and rotation of the detector, and gantry angle, and can describe complex source-detector trajectories. The accuracy and sensitivity of the calibration algorithm was analyzed. The calibration algorithm estimates geometric parameters in a high level of accuracy such that the quality of CT reconstruction is not degraded by the error of estimation. Sensitivity analysis shows uncertainty of 0.01 deg. (around beam direction) to 0.3 deg. (normal to the beam direction) in rotation, and 0.2 mm (orthogonal to the beam direction) to 4.9 mm (beam direction) in position for the medical linear accelerator geometry. Experimental measurements using a laboratory bench Cone-beam CT system of known geometry demonstrate the sensitivity of the method in detecting small changes in the imaging geometry with an uncertainty of 0.1 mm in

  2. ONE-STEP AND TWO-STEP CALIBRATION OF A PORTABLE PANORAMIC IMAGE MAPPING SYSTEM

    Directory of Open Access Journals (Sweden)

    P.-C. Wang

    2012-07-01

    Full Text Available A Portable Panoramic Image Mapping System (PPIMS is proposed for rapid acquisition of three-dimensional spatial information. By considering the convenience of use, cost, weight of equipment, precision, and power supply, the designed PPIMS is equipped with 6 circularly arranged cameras to capture panoramic images and a GPS receiver for positioning. The motivation for this design is to develop a hand-held Mobile Mapping System (MMS for some difficult accessing areas by vehicle MMS, such as rugged terrains, forest areas, heavily damaged disaster areas, and crowed places etc. This PPIMS is in fact a GPS assisted close-range photogrammetric system. Compared with the traditional close-range photogrammetry, PPIMS can reduce the need of ground control points significantly. Under the condition of knowing the relative geometric relationships of the equipped sensors, the elements of exterior orientation of each captured image can be solved. However, the procedure of a system calibration should be done accurately to determine the relative geometric relationships of multi-cameras and the GPS antenna center, before the PPIMS can be applied for geo-referenced mapping. In this paper, both of one-step and two-step calibration procedures for PPIMS are performed to determine the lever-arm offsets and boresight angles among cameras and GPS. The performance of the one-step and two-step calibration is evaluated through the analysis of the experimental results. The comparison between these two calibration procedures was also conducted. The two-step calibration method outperforms the one-step calibration method in terms of calibration accuracy and operation convenience. We expect that the proposed two-step calibration procedure can also be applied to other platform-based MMSs.

  3. Energy and resolution calibration of detectors for noble gas β-γ coincidence system

    International Nuclear Information System (INIS)

    Jia Huaimao; Wang Shilian; Li Qi; Wang Jun; Zhao Yungang; Zhang Xinjun; Fan Yuanqing

    2010-01-01

    The β-γ coincidence technique is a kind of important method to detect radioactive xenon isotopes for the Comprehensive Nuclear-Test-Ban Treaty(CTBT). The energy and resolution calibration of detectors is the first key technique. This paper describes in detail the energy and resolution calibration methods of NaI (Tl) and plastic scintillator detectors for the noble gas β-γ coincidence system SAUNA II-Lab. NaI (Tl) detector's energy and resolution for γ-ray were calibrated with γ radioactive point sources. Plastic scintillator detector's energy and resolution for β-ray were calibrated by Compton scattering electrons of 137 Cs 661.66 keV γ-ray. And the results of β-ray energy resolution calibrated by Compton scattering electrons of 137 Cs were compared with the results of conversion electron of 131 Xe m . In conclusion,it is an easy and feasible method of calibrating plastic scintillator detector's energy by Compton scattering electrons of 137 Cs,but detector's resolution calibrated by Compton scattering electrons is higher than factual result. (authors)

  4. Commercialization plan laser-based decoating systems

    International Nuclear Information System (INIS)

    Freiwald, J.; Freiwald, D.A.

    1998-01-01

    F2 Associates Inc. (F2) is a small, high-technology firm focused on developing and commercializing environmentally friendly laser ablation systems for industrial-rate removal of surface coatings from metals, concrete, and delicate substrates such as composites. F2 has a contract with the US Department of Energy Federal Energy Technology Center (FETC) to develop and test a laser-based technology for removing contaminated paint and other contaminants from concrete and metal surfaces. Task 4.1 in Phase 2 of the Statement of Work for this DOE contract requires that F2 ''document its plans for commercializing and marketing the stationary laser ablation system. This document shall include a discussion of prospects for commercial customers and partners and may require periodic update to reflect changing strategy. This document shall be submitted to the DOE for review.'' This report is being prepared and submitted in fulfillment of that requirement. This report describes the laser-based technology for cleaning and coatings removal, the types of laser-based systems that have been developed by F2 based on this technology, and the various markets that are emerging for this technology. F2's commercialization and marketing plans are described, including how F2's organization is structured to meet the needs of technology commercialization, F2's strategy and marketing approach, and the necessary steps to receive certification for removing paint from aircraft and DOE certification for D and D applications. The future use of the equipment built for the DOE contract is also discussed

  5. Phase Noise Comparision of Short Pulse Laser Systems

    Energy Technology Data Exchange (ETDEWEB)

    S. Zhang; S. V. Benson; J. Hansknecht; D. Hardy; G. Neil; Michelle D. Shinn

    2006-12-01

    This paper describes the phase noise measurement on several different mode-locked laser systems that have completely different gain media and configurations including a multi-kW free-electron laser. We will focus on the state of the art short pulse lasers, especially the drive lasers for photocathode injectors. A comparison between the phase noise of the drive laser pulses, electron bunches and FEL pulses will also be presented.

  6. Method and system for communicating with a laser power driver

    Science.gov (United States)

    Telford, Steven

    2017-07-18

    A system for controlling a plurality of laser diodes includes an optical transmitter coupled to the laser diode driver for each laser diode. An optical signal including bi-phase encoded data is provided to each laser diode driver. The optical signal includes current level and pulse duration information at which each of the diodes is to be driven. Upon receiving a trigger signal, the laser diode drivers operate the laser diodes using the current level and pulse duration information to output a laser beam.

  7. Improving Photometric Calibration of Meteor Video Camera Systems

    Science.gov (United States)

    Ehlert, Steven; Kingery, Aaron; Suggs, Robert

    2017-01-01

    We present the results of new calibration tests performed by the NASA Meteoroid Environment Office (MEO) designed to help quantify and minimize systematic uncertainties in meteor photometry from video camera observations. These systematic uncertainties can be categorized by two main sources: an imperfect understanding of the linearity correction for the MEO's Watec 902H2 Ultimate video cameras and uncertainties in meteor magnitudes arising from transformations between the Watec camera's Sony EX-View HAD bandpass and the bandpasses used to determine reference star magnitudes. To address the first point, we have measured the linearity response of the MEO's standard meteor video cameras using two independent laboratory tests on eight cameras. Our empirically determined linearity correction is critical for performing accurate photometry at low camera intensity levels. With regards to the second point, we have calculated synthetic magnitudes in the EX bandpass for reference stars. These synthetic magnitudes enable direct calculations of the meteor's photometric flux within the camera bandpass without requiring any assumptions of its spectral energy distribution. Systematic uncertainties in the synthetic magnitudes of individual reference stars are estimated at approx. 0.20 mag, and are limited by the available spectral information in the reference catalogs. These two improvements allow for zero-points accurate to 0.05 - 0.10 mag in both filtered and unfiltered camera observations with no evidence for lingering systematics. These improvements are essential to accurately measuring photometric masses of individual meteors and source mass indexes.

  8. Improving the laser brightness of a commercial laser system

    Science.gov (United States)

    Naidoo, Darryl; Litvin, Igor; Forbes, Andrew

    2016-02-01

    We investigate the selection of a flat-top beam and a Gaussian beam inside a laser cavity on opposing mirrors. The concept is tested external to the laser cavity in a single pass and double pass regime where the latter mimics a single round trip in the laser. We implement this intra-cavity selection through the use of two 16 level diffractive optical elements. We consider a solid-state diode side-pumped laser resonator in a typical commercial laser configuration that consists of two planar mirrors where the DOEs are positioned at the mirrors. We out couple the Gaussian and flat-top distributions and we show that we improve the brightness of the laser with active mode control. We also demonstrate that the quality of the beam transformations determine the brightness improvement.

  9. Construction of a large laser fusion system

    International Nuclear Information System (INIS)

    Hurley, C.A.

    1977-01-01

    Construction of a large laser fusion machine is nearing completion at the Lawrence Livermore Laboratory (LLL). Shiva, a 20-terawatt neodymium doped glass system, will be complete in early 1978. This system will have the high power needed to demonstrate significant thermonuclear burn. Shiva will irradiate a microscopic D-T pellet with 20 separate laser beams arriving simultaneously at the target. This requires precise alignment, and stability to maintain alignment. Hardware for the 20 laser chains is composed of 140 amplifiers, 100 spatial filters, 80 isolation stages, 40 large turning mirrors, and a front-end splitter system of over 100 parts. These are mounted on a high stability, three dimensional spaceframe which serves as an optical bench. The mechanical design effort, spanning approximately 3 years, followed a classic engineering evolution. The conceptual design phase led directly to system optimization through cost and technical tradeoffs. Additional manpower was then required for detailed design and specification of hardware and fabrication. Design of long-lead items was started early in order to initiate fabrication and assembly while the rest of the design was completed. All components were ready for assembly and construction as fiscal priorities and schedules permitted

  10. Extrinsic Parameter Calibration for Line Scanning Cameras on Ground Vehicles with Navigation Systems Using a Calibration Pattern

    Directory of Open Access Journals (Sweden)

    Alexander Wendel

    2017-10-01

    Full Text Available Line scanning cameras, which capture only a single line of pixels, have been increasingly used in ground based mobile or robotic platforms. In applications where it is advantageous to directly georeference the camera data to world coordinates, an accurate estimate of the camera’s 6D pose is required. This paper focuses on the common case where a mobile platform is equipped with a rigidly mounted line scanning camera, whose pose is unknown, and a navigation system providing vehicle body pose estimates. We propose a novel method that estimates the camera’s pose relative to the navigation system. The approach involves imaging and manually labelling a calibration pattern with distinctly identifiable points, triangulating these points from camera and navigation system data and reprojecting them in order to compute a likelihood, which is maximised to estimate the 6D camera pose. Additionally, a Markov Chain Monte Carlo (MCMC algorithm is used to estimate the uncertainty of the offset. Tested on two different platforms, the method was able to estimate the pose to within 0.06 m/1.05 ∘ and 0.18 m/2.39 ∘ . We also propose several approaches to displaying and interpreting the 6D results in a human readable way.

  11. A flexible 3D laser scanning system using a robotic arm

    Science.gov (United States)

    Fei, Zixuan; Zhou, Xiang; Gao, Xiaofei; Zhang, Guanliang

    2017-06-01

    In this paper, we present a flexible 3D scanning system based on a MEMS scanner mounted on an industrial arm with a turntable. This system has 7-degrees of freedom and is able to conduct a full field scan from any angle, suitable for scanning object with the complex shape. The existing non-contact 3D scanning system usually uses laser scanner that projects fixed stripe mounted on the Coordinate Measuring Machine (CMM) or industrial robot. These existing systems can't perform path planning without CAD models. The 3D scanning system presented in this paper can scan the object without CAD models, and we introduced this path planning method in the paper. We also propose a practical approach to calibrating the hand-in-eye system based on binocular stereo vision and analyzes the errors of the hand-eye calibration.

  12. Collimation system for a laboratory of primary and secondary ionizing radiation calibration

    International Nuclear Information System (INIS)

    Oliveira, S.R.; David, M.G.

    2003-01-01

    This work is part of a cooperation plan between the LNMRI/IRD and the LCR/UERJ, for the a primary calibration at the IRD and a secondary laboratory at the LCR, both calibrated for mammographic beams which will be part a Calibration National Network. For the mounting of the primary laboratory, the first step was to install two additional collimators in order to guarantee that the beam area over the ionization chamber to satisfy the calibration international standards. So, the collimators were constructed obeying the geometric rules, the first being of conic format and the second of the cylindrical format, therefore avoiding the effects of the scattering radiation on the edges. By using this collimation system it was possible to verify the uniformity of the radiation field incident the ionization chamber to be over 98% of the total area, guaranteeing better precision of the measurement

  13. Transponder-aided joint calibration and synchronization compensation for distributed radar systems.

    Science.gov (United States)

    Wang, Wen-Qin

    2015-01-01

    High-precision radiometric calibration and synchronization compensation must be provided for distributed radar system due to separate transmitters and receivers. This paper proposes a transponder-aided joint radiometric calibration, motion compensation and synchronization for distributed radar remote sensing. As the transponder signal can be separated from the normal radar returns, it is used to calibrate the distributed radar for radiometry. Meanwhile, the distributed radar motion compensation and synchronization compensation algorithms are presented by utilizing the transponder signals. This method requires no hardware modifications to both the normal radar transmitter and receiver and no change to the operating pulse repetition frequency (PRF). The distributed radar radiometric calibration and synchronization compensation require only one transponder, but the motion compensation requires six transponders because there are six independent variables in the distributed radar geometry. Furthermore, a maximum likelihood method is used to estimate the transponder signal parameters. The proposed methods are verified by simulation results.

  14. Laser fusion systems for industrial process heat. Third semiannual report

    International Nuclear Information System (INIS)

    Bates, F.J.; Denning, R.S.; Dykhuizen, R.C.; Goldthwaite, W.H.; Kok, K.D.; Skelton, J.C.

    1979-01-01

    This report concentrates not only on the design of the laser fusion system but also on the cost of this system and the costs of alternative sources of energy that are expected to be in competition with the laser fusion system. The absolute values of the cost of the laser fusion system are limited by the estimates of the cost of the components and subsystems making up the laser fusion energy station. The method used in calculating costs of the laser fusion and alternative systems are laid out in detail

  15. Optical System Error Analysis and Calibration Method of High-Accuracy Star Trackers

    Directory of Open Access Journals (Sweden)

    Zheng You

    2013-04-01

    Full Text Available The star tracker is a high-accuracy attitude measurement device widely used in spacecraft. Its performance depends largely on the precision of the optical system parameters. Therefore, the analysis of the optical system parameter errors and a precise calibration model are crucial to the accuracy of the star tracker. Research in this field is relatively lacking a systematic and universal analysis up to now. This paper proposes in detail an approach for the synthetic error analysis of the star tracker, without the complicated theoretical derivation. This approach can determine the error propagation relationship of the star tracker, and can build intuitively and systematically an error model. The analysis results can be used as a foundation and a guide for the optical design, calibration, and compensation of the star tracker. A calibration experiment is designed and conducted. Excellent calibration results are achieved based on the calibration model. To summarize, the error analysis approach and the calibration method are proved to be adequate and precise, and could provide an important guarantee for the design, manufacture, and measurement of high-accuracy star trackers.

  16. Optical system error analysis and calibration method of high-accuracy star trackers.

    Science.gov (United States)

    Sun, Ting; Xing, Fei; You, Zheng

    2013-04-08

    The star tracker is a high-accuracy attitude measurement device widely used in spacecraft. Its performance depends largely on the precision of the optical system parameters. Therefore, the analysis of the optical system parameter errors and a precise calibration model are crucial to the accuracy of the star tracker. Research in this field is relatively lacking a systematic and universal analysis up to now. This paper proposes in detail an approach for the synthetic error analysis of the star tracker, without the complicated theoretical derivation. This approach can determine the error propagation relationship of the star tracker, and can build intuitively and systematically an error model. The analysis results can be used as a foundation and a guide for the optical design, calibration, and compensation of the star tracker. A calibration experiment is designed and conducted. Excellent calibration results are achieved based on the calibration model. To summarize, the error analysis approach and the calibration method are proved to be adequate and precise, and could provide an important guarantee for the design, manufacture, and measurement of high-accuracy star trackers.

  17. A Visual Servoing-Based Method for ProCam Systems Calibration

    Directory of Open Access Journals (Sweden)

    Jeremie Mosnier

    2013-10-01

    Full Text Available Projector-camera systems are currently used in a wide field of applications, such as 3D reconstruction and augmented reality, and can provide accurate measurements, depending on the configuration and calibration. Frequently, the calibration task is divided into two steps: camera calibration followed by projector calibration. The latter still poses certain problems that are not easy to solve, such as the difficulty in obtaining a set of 2D–3D points to compute the projection matrix between the projector and the world. Existing methods are either not sufficiently accurate or not flexible. We propose an easy and automatic method to calibrate such systems that consists in projecting a calibration pattern and superimposing it automatically on a known printed pattern. The projected pattern is provided by a virtual camera observing a virtual pattern in an OpenGL model. The projector displays what the virtual camera visualizes. Thus, the projected pattern can be controlled and superimposed on the printed one with the aid of visual servoing. Our experimental results compare favorably with those of other methods considering both usability and accuracy.

  18. Calibration of the Accuscan II In Vivo System for Whole Body Counting

    Energy Technology Data Exchange (ETDEWEB)

    Orval R. Perry; David L. Georgeson

    2011-08-01

    This report describes the April 2011 calibration of the Accuscan II HpGe In Vivo system for whole body counting. The source used for the calibration was a NIST traceable BOMAB manufactured by DOE as INL2006 BOMAB containing Eu-154, Eu-155, Eu-152, Sb-125 and Y-88 with energies from 27 keV to 1836 keV with a reference date of 11/29/2006. The actual usable energy range was 86.5 keV to 1597 keV on 4/21/2011. The BOMAB was constructed inside the Accuscan II counting 'tub' in the order of legs, thighs, abdomen, thorax/arms, neck, and head. Each piece was taped to the backwall of the counter. The arms were taped to the thorax. The phantom was constructed between the v-ridges on the backwall of the Accuscan II counter. The energy and efficiency calibrations were performed using the INL2006 BOMAB. The calibrations were performed with the detectors in the scanning mode. This report includes an overview introduction and records for the energy/FWHM and efficiency calibration including performance verification and validation counting. The Accuscan II system was successfully calibrated for whole body counting and verified in accordance with ANSI/HPS N13.30-1996 criteria.

  19. Laser fusion hybrid reactor systems study

    International Nuclear Information System (INIS)

    1976-07-01

    The work was performed in three phases. The first phase included a review of the many possible laser-reactor-blanket combinations and resulted in the selection of a ''demonstration size'' 500 MWe plant for further study. A number of fast fission blankets using uranium metal, uranium-molybdenum alloy, and uranium carbide as fuel were investigated. The second phase included design of the reactor vessel and internals, heat transfer system, tritium processing system, and the balance of plant, excluding the laser building and equipment. A fuel management scheme was developed, safety considerations were reviewed, and capital and operating costs were estimated. Costs developed during the second phase were unexpectedly high, and a thorough review indicated considerable unit cost savings could be obtained by scaling the plant to a larger size. Accordingly, a third phase was added to the original scope, encompassing the redesign and scaling of the plant from 500 MWe to 1200 MWe

  20. Research on correction algorithm of laser positioning system based on four quadrant detector

    Science.gov (United States)

    Gao, Qingsong; Meng, Xiangyong; Qian, Weixian; Cai, Guixia

    2018-02-01

    This paper first introduces the basic principle of the four quadrant detector, and a set of laser positioning experiment system is built based on the four quadrant detector. Four quadrant laser positioning system in the actual application, not only exist interference of background light and detector dark current noise, and the influence of random noise, system stability, spot equivalent error can't be ignored, so it is very important to system calibration and correction. This paper analyzes the various factors of system positioning error, and then propose an algorithm for correcting the system error, the results of simulation and experiment show that the modified algorithm can improve the effect of system error on positioning and improve the positioning accuracy.

  1. Hard target LIDAR calibration for SO2

    CSIR Research Space (South Africa)

    Du Plessis, A

    2006-01-01

    Full Text Available calibration for SO2 A du Plessis, DE Roberts CSIR National Laser Centre, Pretoria Slide 2 © CSIR 2006 www.csir.co.za Project background • Las-R-MAP: Laser – Remote – Measurement of Atmospheric Pollutants • Mobile laser system....csir.co.za Hard target backscatter ∫ = − R dRRn p e R RcE RS 0 )(2 2 )()( λσ λ β S R Slide 10 © CSIR 2006 www.csir.co.za Las-R-MAP hardware: laser system Slide 11 © CSIR 2006 www.csir.co.za Las-R...

  2. Guide for selection and calibration of dosimetry systems for radiation processing

    International Nuclear Information System (INIS)

    2002-01-01

    This guide covers the basis for selecting and calibrating dosimetry systems used to measure absorbed dose in gamma ray or X-ray fields and in electron beams used for radiation processing. It discusses the types of dosimetry systems that may be employed during calibration or on a routine basis as part of quality assurance in commercial radiation processing of products. This guide also discusses interpretation of absorbed dose and briefly outlines measurements of the uncertainties associated with the dosimetry. The details of the calibration of the analytical instrumentation are addressed in individual dosimetry system standard practices. The absorbed-dose range covered is up to 1 MGy (100 Mrad). Source energies covered are from 0.1 to 50 MeV photons and electrons. This guide should be used along with standard practices and guides for specific dosimetry systems and applications covered in other standards. Dosimetry for radiation processing with neutrons or heavy charged particles is not covered in this guide

  3. The Data Acquisition and Calibration System for the ATLAS Semiconductor Tracker

    CERN Document Server

    Abdesselam, A; Barr, A J; Bell, P; Bernabeu, J; Butterworth, J M; Carter, J R; Carter, A A; Charles, E; Clark, A; Colijn, A P; Costa, M J; Dalmau, J M; Demirkoz, B; Dervan, P J; Donega, M; D'Onifrio, M; Escobar, C; Fasching, D; Ferguson, D P S; Ferrari, P; Ferrère, D; Fuster, J; Gallop, B; García, C; González, S; González-Sevilla, S; Goodrick, M J; Gorisek, A; Greenall, A; Grillo, A A; Hessey, N P; Hill, J C; Jackson, J N; Jared, R C; Johannson, P D C; de Jong, P; Joseph, J; Lacasta, C; Lane, J B; Lester, C G; Limper, M; Lindsay, S W; McKay, R L; Magrath, C A; Mangin-Brinet, M; Martí i García, S; Mellado, B; Meyer, W T; Mikulec, B; Minano, M; Mitsou, V A; Moorhead, G; Morrissey, M; Paganis, E; Palmer, M J; Parker, M A; Pernegger, H; Phillips, A; Phillips, P W; Postranecky, M; Robichaud-Véronneau, A; Robinson, D; Roe, S; Sandaker, H; Sciacca, F; Sfyrla, A; Stanecka, E; Stapnes, S; Stradling, A; Tyndel, M; Tricoli, A; Vickey, T; Vossebeld, J H; Warren, M R M; Weidberg, A R; Wells, P S; Wu, S L

    2008-01-01

    The SemiConductor Tracker (SCT) data acquisition (DAQ) system will calibrate, configure, and control the approximately six million front-end channels of the ATLAS silicon strip detector. It will provide a synchronized bunch-crossing clock to the front-end modules, communicate first-level triggers to the front-end chips, and transfer information about hit strips to the ATLAS high-level trigger system. The system has been used extensively for calibration and quality assurance during SCT barrel and endcap assembly and for performance confirmation tests after transport of the barrels and endcaps to CERN. Operating in data-taking mode, the DAQ has recorded nearly twenty million synchronously-triggered events during commissioning tests including almost a million cosmic ray triggered events. In this paper we describe the components of the data acquisition system, discuss its operation in calibration and data-taking modes and present some detector performance results from these tests.

  4. The data acquisition and calibration system for the ATLAS Semiconductor Tracker

    International Nuclear Information System (INIS)

    Abdesselam, A; Barr, A J; Demirkoez, B; Barber, T; Carter, J R; Bell, P; Bernabeu, J; Costa, M J; Escobar, C; Butterworth, J M; Carter, A A; Dalmau, J M; Charles, E; Fasching, D; Ferguson, D P S; Clark, A; Donega, M; D'Onifrio, M; Colijn, A-P; Dervan, P J

    2008-01-01

    The SemiConductor Tracker (SCT) data acquisition (DAQ) system will calibrate, configure, and control the approximately six million front-end channels of the ATLAS silicon strip detector. It will provide a synchronized bunch-crossing clock to the front-end modules, communicate first-level triggers to the front-end chips, and transfer information about hit strips to the ATLAS high-level trigger system. The system has been used extensively for calibration and quality assurance during SCT barrel and endcap assembly and for performance confirmation tests after transport of the barrels and endcaps to CERN. Operating in data-taking mode, the DAQ has recorded nearly twenty million synchronously-triggered events during commissioning tests including almost a million cosmic ray triggered events. In this paper we describe the components of the data acquisition system, discuss its operation in calibration and data-taking modes and present some detector performance results from these tests

  5. Research on direct calibration method of eye-to-hand system of robot

    Science.gov (United States)

    Hu, Xiaoping; Xie, Ke; Peng, Tao

    2013-10-01

    In the position-based visual servoing control for robot, the hand-eye calibration is very important because it can affect the control precision of the system. According to the robot with eye-to-hand stereovision system, this paper proposes a direct method of hand-eye calibration. The method utilizes the triangle measuring principle to solve the coordinates in the camera coordinate system of scene point. It calculates the estimated coordinates by the hand-eye calibration equation set which indicates the transformational relation from the robot to the camera coordinate system, and then uses the error of actual and estimated coordinates to establish the objective function. Finally the method substitutes the parameters into the function repeatedly until it converged to optimize the result. The related experiment compared the measured coordinates with the actual coordinates, shows the efficiency and the precision of it.

  6. System for combining laser beams of diverse frequencies

    International Nuclear Information System (INIS)

    1980-01-01

    A system is described for combining laser beams of different frequencies into a number of beams each comprising laser radiation having components of each of the different frequencies. The system can be used in laser isotope separation facilities. (U.K.)

  7. Laser surveillance systems for fuel storage pools

    International Nuclear Information System (INIS)

    Boeck, H.

    1985-06-01

    A Laser Surveillance System (LASSY) as a new safeguards device has been developed under the IAEA research contract No. 3458/RB at the Atominstitut Wien using earlier results by S. Fiarman. This system is designed to act as a sheet of light covering spent fuel assemblies in spent fuel storage pools. When movement of assemblies takes place, LASSY detects and locates the position of the movement in the pool and when interrogated, presents a list of pool positions and times of movement to the safeguards inspector. A complete prototype system was developed and built. Full scale tests showed the principal working capabilities of a LASSY underwater

  8. Laser control of natural disperse systems

    Science.gov (United States)

    Vlasova, Olga L.; Bezrukova, Alexandra G.

    2003-10-01

    Different water disperse systems were studied by integral (spectroturbidemetry) and differential light scattering method with a laser as a source of light. The investigation done concerns the state of kaolin dispersions at storage and under dilution as an example of mineral dispersion systems such as natural water. The role of some light scattering parameters for an optical analysis of water dispersions, like the dispersion of erythrocytes and bacterial cells -Escherichia coli is discussed. The results obtained can help to elaborate the methods for on-line optical control fo natural disperse systems (water, air) with mineral and biological particles.

  9. Calibration of controlling input models for pavement management system.

    Science.gov (United States)

    2013-07-01

    The Oklahoma Department of Transportation (ODOT) is currently using the Deighton Total Infrastructure Management System (dTIMS) software for pavement management. This system is based on several input models which are computational backbones to dev...

  10. Mode-Locked Semiconductor Lasers for Optical Communication Systems

    DEFF Research Database (Denmark)

    Yvind, Kresten; Larsson, David; Oxenløwe, Leif Katsuo

    2005-01-01

    We present investigations on 10 and 40 GHz monolithic mode-locked lasers for applications in optical communications systems. New all-active lasers with one to three quantum wells have been designed, fabricated and characterized....

  11. A novel single-step, multipoint calibration method for instrumented Lab-on-Chip systems

    DEFF Research Database (Denmark)

    Pfreundt, Andrea; Patou, François; Zulfiqar, Azeem

    2014-01-01

    for instrument-based PoC blood biomarker analysis systems. Motivated by the complexity of associating high-accuracy biosensing using silicon nanowire field effect transistors with ease of use for the PoC system user, we propose a novel one-step, multipoint calibration method for LoC-based systems. Our approach...... specifically addresses the important interfaces between a novel microfluidic unit to integrate the sensor array and a mobile-device hardware accessory. A multi-point calibration curve is obtained by generating a defined set of reference concentrations from a single input. By consecutively splitting the flow...

  12. Presentation, calibration and validation of the low-order, DCESS Earth System Model

    DEFF Research Database (Denmark)

    Shaffer, G.; Olsen, S. Malskaer; Pedersen, Jens Olaf Pepke

    2008-01-01

    A new, low-order Earth system model is described, calibrated and tested against Earth system data. The model features modules for the atmosphere, ocean, ocean sediment, land biosphere and lithosphere and has been designed to simulate global change on time scales of years to millions of years...... remineralization. The lithosphere module considers outgassing, weathering of carbonate and silicate rocks and weathering of rocks containing old organic carbon and phosphorus. Weathering rates are related to mean atmospheric temperatures. A pre-industrial, steady state calibration to Earth system data is carried...

  13. Calibration Measurements of the LHC Beam Dumping System Extraction Kicker Magnets

    CERN Document Server

    Uythoven, J; Ducimetière, L; Goddard, B; Gräwer, G; Olivieri, F; Pereira, L; Vossenberg, Eugène B

    2006-01-01

    The LHC beam dumping system must protect the LHC machine from damage by reliably and safely extracting and absorbing the circulating beams when requested. Two sets of 15 extraction kicker magnets form the main active part of this system. They have been produced, tested and calibrated by measuring the integrated magnetic field and the magnet current at different beam energies. The calibration data have been analysed, and the critical parameters are compared with the specifications. Implications for the configuration, control and operation of the beam dumping system are discussed.

  14. High precision, low disturbance calibration of the High Voltage system of the CMS Barrel Electromagnetic Calorimeter

    CERN Document Server

    Marzocchi, Badder

    2017-01-01

    The CMS Electromagnetic Calorimeter is made of scintillating lead tungstate crystals, using avalanche photodiodes (APD) as photo-detectors in the barrel part. The high voltage system, consisting of 1224 channels, biases groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3pct/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  15. Analysis on Calibration and Uncertainty for TD-LTE Radio Test System

    Directory of Open Access Journals (Sweden)

    Zhang Weipeng

    2014-06-01

    Full Text Available TD-LTE base station radio test system measures radio signal with a required accuracy, so calibration need to be done for transmission path between base station and measurement instruments before test. Considering Transmitter OFF Power measurement within OFF period, modulated signal generator and spectrum analyzer inside test system is used for calibration, to get accurate transmission parameters of the paths, and to reduce test cost without more instruments. The paper describes the uncertainty of test system, analyzes uncertainty contribution of interface mismatch, calculates uncertainty for Transmitter OFF Power measurement, uncertainty is 1.193 dB, within the requirement of 3GPP specification.

  16. Laser experimental system as teaching aid for demonstrating basic phenomena of laser feedback

    International Nuclear Information System (INIS)

    Xu, Ling; Zhao, Shijie; Zhang, Shulian

    2015-01-01

    An experimental laser teaching system is developed to demonstrate laser feedback phenomena, which bring great harm to optical communication and benefits to precision measurement. The system consists of an orthogonally polarized He-Ne laser, a feedback mirror which reflects the laser output light into the laser cavity, and an optical attenuator which changes the intensity of the feedback light. As the feedback mirror is driven by a piezoelectric ceramic, the attenuator is adjusted and the feedback mirror is tilted, the system can demonstrate many basic laser feedback phenomena, including weak, moderate and strong optical feedback, multiple feedback and polarization flipping. Demonstrations of these phenomena can give students a better understanding about the intensity and polarization of lasers. The system is well designed and assembled, simple to operate, and provides a valuable teaching aid at an undergraduate level. (paper)

  17. Calibration of the Failed-Fuel-Element Detection Systems in the Aagesta Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Strindehag, O

    1966-06-15

    Results from a calibration of the systems for detection of fuel element ruptures in the Aagesta reactor are presented. The calibration was carried out by means of foils of zirconium-uranium alloy which were placed in a special fuel assembly. The release of fission products from these foils is due mainly to recoil and can be accurately calculated. Before the foils were used in the reactor their corrosion behaviour in high temperature water was investigated. The results obtained with the precipitator systems for bulk detection and localization are in good agreement with the expected performance. The sensitivity of these systems was found to be high enough for detection and localization of small defects of pin-hole type ({nu} = 10{sup -8}/s ). The general performance of the systems was satisfactory during the calibration tests, although a few adjustments are desirable. A bulk detecting system for monitoring of activities in the moderator, in which the {gamma}-radiation from coolant samples is measured directly after an ion exchanger, showed lower sensitivity than expected from calculations. It seems that the sensitivity of the latter system has to be improved to admit the detection of small defects. In the ion exchanger system, and to some extent in the precipitator systems, the background from A{sup 41} in the coolant limits the sensitivity. The calibration technique utilized seems to be of great advantage when investigating the performance of failed-fuel-element detection systems.

  18. NEW METHOD FOR THE CALIBRATION OF MULTI-CAMERA MOBILE MAPPING SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. P. Kersting

    2012-07-01

    Full Text Available Mobile Mapping Systems (MMS allow for fast and cost-effective collection of geo-spatial information. Such systems integrate a set of imaging sensors and a position and orientation system (POS, which entails GPS and INS units. System calibration is a crucial process to ensure the attainment of the expected accuracy of such systems. It involves the calibration of the individual sensors as well as the calibration of the mounting parameters relating the system components. The mounting parameters of multi-camera MMS include two sets of relative orientation parameters (ROP: the lever arm offsets and the boresight angles relating the cameras and the IMU body frame and the ROP among the cameras (in the absence of GPS/INS data. In this paper, a novel single-step calibration method, which has the ability of estimating these two sets of ROP, is devised. Besides the ability to estimate the ROP among the cameras, the proposed method can use such parameters as prior information in the ISO procedure. The implemented procedure consists of an integrated sensor orientation (ISO where the GPS/INS-derived position and orientation and the system mounting parameters are directly incorporated in the collinearity equations. The concept of modified collinearity equations has been used by few authors for single-camera systems. In this paper, a new modification to the collinearity equations for GPS/INS-assisted multicamera systems is introduced. Experimental results using a real dataset demonstrate the feasibility of the proposed method.

  19. New Method for the Calibration of Multi-Camera Mobile Mapping Systems

    Science.gov (United States)

    Kersting, A. P.; Habib, A.; Rau, J.

    2012-07-01

    Mobile Mapping Systems (MMS) allow for fast and cost-effective collection of geo-spatial information. Such systems integrate a set of imaging sensors and a position and orientation system (POS), which entails GPS and INS units. System calibration is a crucial process to ensure the attainment of the expected accuracy of such systems. It involves the calibration of the individual sensors as well as the calibration of the mounting parameters relating the system components. The mounting parameters of multi-camera MMS include two sets of relative orientation parameters (ROP): the lever arm offsets and the boresight angles relating the cameras and the IMU body frame and the ROP among the cameras (in the absence of GPS/INS data). In this paper, a novel single-step calibration method, which has the ability of estimating these two sets of ROP, is devised. Besides the ability to estimate the ROP among the cameras, the proposed method can use such parameters as prior information in the ISO procedure. The implemented procedure consists of an integrated sensor orientation (ISO) where the GPS/INS-derived position and orientation and the system mounting parameters are directly incorporated in the collinearity equations. The concept of modified collinearity equations has been used by few authors for single-camera systems. In this paper, a new modification to the collinearity equations for GPS/INS-assisted multicamera systems is introduced. Experimental results using a real dataset demonstrate the feasibility of the proposed method.

  20. Vibration transducer calibration techniques

    Science.gov (United States)

    Brinkley, D. J.

    1980-09-01

    Techniques for the calibration of vibration transducers used in the Aeronautical Quality Assurance Directorate of the British Ministry of Defence are presented. Following a review of the types of measurements necessary in the calibration of vibration transducers, the performance requirements of vibration transducers, which can be used to measure acceleration, velocity or vibration amplitude, are discussed, with particular attention given to the piezoelectric accelerometer. Techniques for the accurate measurement of sinusoidal vibration amplitude in reference-grade transducers are then considered, including the use of a position sensitive photocell and the use of a Michelson laser interferometer. Means of comparing the output of working-grade accelerometers with that of previously calibrated reference-grade devices are then outlined, with attention given to a method employing a capacitance bridge technique and a method to be used at temperatures between -50 and 200 C. Automatic calibration procedures developed to speed up the calibration process are outlined, and future possible extensions of system software are indicated.

  1. Larger Optics and Improved Calibration Techniques for Small Satellite Observations with the ERAU OSCOM System

    Science.gov (United States)

    Bilardi, S.; Barjatya, A.; Gasdia, F.

    OSCOM, Optical tracking and Spectral characterization of CubeSats for Operational Missions, is a system capable of providing time-resolved satellite photometry using commercial-off-the-shelf (COTS) hardware and custom tracking and analysis software. This system has acquired photometry of objects as small as CubeSats using a Celestron 11” RASA and an inexpensive CMOS machine vision camera. For satellites with known shapes, these light curves can be used to verify a satellite’s attitude and the state of its deployed solar panels or antennae. While the OSCOM system can successfully track satellites and produce light curves, there is ongoing improvement towards increasing its automation while supporting additional mounts and telescopes. A newly acquired Celestron 14” Edge HD can be used with a Starizona Hyperstar to increase the SNR for small objects as well as extend beyond the limiting magnitude of the 11” RASA. OSCOM currently corrects instrumental brightness measurements for satellite range and observatory site average atmospheric extinction, but calibrated absolute brightness is required to determine information about satellites other than their spin rate, such as surface albedo. A calibration method that automatically detects and identifies background stars can use their catalog magnitudes to calibrate the brightness of the satellite in the image. We present a photometric light curve from both the 14” Edge HD and 11” RASA optical systems as well as plans for a calibration method that will perform background star photometry to efficiently determine calibrated satellite brightness in each frame.

  2. Synchronised laser chaos communication: statistical investigation of an experimental system

    OpenAIRE

    Lawrance, Anthony J.; Papamarkou, Theodore; Uchida, Atsushi

    2017-01-01

    The paper is concerned with analyzing data from an experimental antipodal laser-based chaos shift-keying communication system. Binary messages are embedded in a chaotically behaving laser wave which is transmitted through a fiber-optic cable and are decoded at the receiver using a second laser synchronized with the emitter laser. Instrumentation in the experimental system makes it particularly interesting to be able to empirically analyze both optical noise and synchronization error as well a...

  3. The LED and fiber based calibration system for the photomultiplier array of SNO+

    Science.gov (United States)

    Seabra, L.; Alves, R.; Andringa, S.; Bradbury, S.; Carvalho, J.; Clark, K.; Coulter, I.; Descamps, F.; Falk, L.; Gurriana, L.; Kraus, C.; Lefeuvre, G.; Maio, A.; Maneira, J.; Mottram, M.; Peeters, S.; Rose, J.; Sinclair, J.; Skensved, P.; Waterfield, J.; White, R.; Wilson, J.; SNO+ Collaboration

    2015-02-01

    A new external LED/fiber light injection calibration system was designed for the calibration and monitoring of the photomultiplier array of the SNO+ experiment at SNOLAB. The goal of the calibration system is to allow an accurate and regular measurement of the photomultiplier array's performance, while minimizing the risk of radioactivity ingress. The choice in SNO+ was to use a set of optical fiber cables to convey into the detector the light pulses produced by external LEDs. The quality control was carried out using a modified test bench that was used in QC of optical fibers for TileCal/ATLAS. The optical fibers were characterized for transmission, timing and angular dispersions. This article describes the setups used for the characterization and quality control of the system based on LEDs and optical fibers and their results.

  4. Lasers in tattoo and pigmentation control: role of the PicoSure(®) laser system.

    Science.gov (United States)

    Torbeck, Richard; Bankowski, Richard; Henize, Sarah; Saedi, Nazanin

    2016-01-01

    The use of picosecond lasers to remove tattoos has greatly improved due to the long-standing outcomes of nanosecond lasers, both clinically and histologically. The first aesthetic picosecond laser available for this use was the PicoSure(®) laser system (755/532 nm). Now that a vast amount of research on its use has been conducted, we performed a comprehensive review of the literature to validate the continued application of the PicoSure(®) laser system for tattoo removal. A PubMed search was conducted using the term "picosecond" combined with "laser", "dermatology", and "laser tattoo removal". A total of 13 articles were identified, and ten of these met the inclusion criteria for this review. The majority of studies showed that picosecond lasers are an effective and safe treatment mode for the removal of tattoo pigments. Several studies also indicated potential novel applications of picosecond lasers in the removal of various tattoo pigments (eg, black, red, and yellow). Adverse effects were generally mild, such as transient hypopigmentation or blister formation, and were rarely more serious, such as scarring and/or textural change. Advancements in laser technologies and their application in cutaneous medicine have revolutionized the field of laser surgery. Computational modeling provides evidence that the optimal pulse durations for tattoo ink removal are in the picosecond domain. It is recommended that the PicoSure(®) laser system continue to be used for safe and effective tattoo removal, including for red and yellow pigments.

  5. Performance and calibration of the CHORUS scintillating fiber tracker and opto-electronics readout system

    International Nuclear Information System (INIS)

    Annis, P.; Aoki, S.; Brunner, J.; De Jong, M.; Fabre, J.P.; Ferreira, R.; Flegel, W.; Frekers, D.; Gregoire, G.; Herin, J.; Kobayashi, M.; Konijn, J.; Lemaitre, V.; Macina, D.; Meijer Drees, R.; Meinhard, H.; Michel, L.; Mommaert, C.; Nakamura, K.; Nakamura, M.; Nakano, T.; Niwa, K.; Niu, E.; Panman, J.; Riccardi, F.; Rondeshagen, D.; Sato, O.; Stefanini, G.; Vander Donckt, M.; Vilain, P.; Wilquet, G.; Winter, K.; Wong, H.T.

    1995-01-01

    An essential component of the CERN WA95/CHORUS experiment is a scintillating fiber tracker system for precise track reconstruction of particles. The tracker design, its opto-electronics readout and calibration system are discussed. Performances of the detector are presented. (orig.)

  6. GESCAL: Quality management automated system for a calibration and test laboratory

    International Nuclear Information System (INIS)

    Manzano de Armas, J.; Valdes Ramos, M.; Morales Monzon, J.A.

    1998-01-01

    GESCAL is a software created to automate all elements composing the quality system in a calibration and test laboratory. It also evaluates quality according to its objectives and policies. This integrated data system decreases considerably the amount of time devoted to manage quality. It is speedier in searching and evaluating information registers thus notably in reducing the workload for laboratory staff

  7. Comparison of three different laser systems for application in dentistry

    Science.gov (United States)

    Mindermann, Anja; Niemz, M. H.; Eisenmann, L.; Loesel, Frieder H.; Bille, Josef F.

    1993-12-01

    Three different laser systems have been investigated according to their possible application in dentistry: a free running and a Q-switched microsecond Ho:YAG laser, a free running microsecond Er:YAG laser and picosecond Nd:YLF laser system consisting of an actively mode locked oscillator and a regenerative amplifier. The experiments focused on the question if lasers can support or maybe replace ordinary drilling machines. For this purpose several cavities were generated with the lasers mentioned above. Their depth and quality were judged by light and electron microscopy. The results of the experiments showed that the picosecond Nd:YLF laser system has advantages compared to other lasers regarding their application in dentistry.

  8. Laser-start-up system for magnetic mirror fusion

    International Nuclear Information System (INIS)

    Frank, A.M.; Thomas, S.R.; Denhoy, B.S.; Chargin, A.K.

    1976-01-01

    A CO 2 laser system has been developed at LLL to provide hot start-up plasmas for magnetic mirror fusion experiments. A frozen ammonia pellet is irradiated with a laser power density in excess of 10 13 W/cm 2 in a 50-ns pulse. This system uses commercially available laser systems. Optical components were fabricated both by direct machining and standard techniques. The technologies used in this system are directly applicable to reactor scale systems

  9. Self-calibration of a cone-beam micro-CT system

    International Nuclear Information System (INIS)

    Patel, V.; Chityala, R. N.; Hoffmann, K. R.; Ionita, C. N.; Bednarek, D. R.; Rudin, S.

    2009-01-01

    Use of cone-beam computed tomography (CBCT) is becoming more frequent. For proper reconstruction, the geometry of the CBCT systems must be known. While the system can be designed to reduce errors in the geometry, calibration measurements must still be performed and corrections applied. Investigators have proposed techniques using calibration objects for system calibration. In this study, the authors present methods to calibrate a rotary-stage CB micro-CT (CBμCT) system using only the images acquired of the object to be reconstructed, i.e., without the use of calibration objects. Projection images are acquired using a CBμCT system constructed in the authors' laboratories. Dark- and flat-field corrections are performed. Exposure variations are detected and quantified using analysis of image regions with an unobstructed view of the x-ray source. Translations that occur during the acquisition in the horizontal direction are detected, quantified, and corrected based on sinogram analysis. The axis of rotation is determined using registration of antiposed projection images. These techniques were evaluated using data obtained with calibration objects and phantoms. The physical geometric axis of rotation is determined and aligned with the rotational axis (assumed to be the center of the detector plane) used in the reconstruction process. The parameters describing this axis agree to within 0.1 mm and 0.3 deg with those determined using other techniques. Blurring due to residual calibration errors has a point-spread function in the reconstructed planes with a full-width-at-half-maximum of less than 125 μm in a tangential direction and essentially zero in the radial direction for the rotating object. The authors have used this approach on over 100 acquisitions over the past 2 years and have regularly obtained high-quality reconstructions, i.e., without artifacts and no detectable blurring of the reconstructed objects. This self-calibrating approach not only obviates

  10. Calibration and quality assurance for rounded leaf-end MLC systems

    International Nuclear Information System (INIS)

    Graves, Maria N.; Thompson, Antoinette V.; Martel, Mary K.; McShan, Daniel L.; Fraass, Benedick A.

    2001-01-01

    Multileaf collimator (MLC) systems are available on most commercial linear accelerators, and many of these MLC systems utilize a design with rounded leaf ends and linear motion of the leaves. In this kind of system, the agreement between the digital MLC position readouts and the light field or radiation field edges must be achieved with software, since the leaves do not move in a focused motion like that used for most collimator jaw systems. In this work we address a number of the calibration and quality assurance issues associated with the acceptance, commissioning, and routine clinical use of this type of MLC system. These issues are particularly important for MLCs used for various types of intensity modulated radiation therapy (IMRT) and small, conformal fields. For rounded leaf end MLCs, it is generally not possible to make both the light and radiation field edges agree with the digital readout, so differences between the two kinds of calibrations are illustrated in this work using one vendor's MLC system. It is increasingly critical that the MLC leaf calibration be very consistent with the radiation field edges, so in this work a methodology for performing accurate radiation field size calibration is discussed. A system external to the vendor's MLC control system is used to correct or handle limitations in the MLC control system. When such a system of corrections is utilized, it is found that the MLC radiation field size can be defined with an accuracy of approximately 0.3 mm, much more accurate than most vendor's specifications for MLC accuracy. Quality assurance testing for such a calibration correction system is also demonstrated

  11. A new calibration method for tri-axial field sensors in strap-down navigation systems

    International Nuclear Information System (INIS)

    Li, Xiang; Li, Zhi

    2012-01-01

    This paper presents a novel calibration method for tri-axial field sensors, such as magnetometers and accelerometers, in strap-down navigation systems. Strap-down tri-axial sensors have been widely used as they have the advantages of small size and low cost, but they need to be calibrated in order to ensure their accuracy. The most commonly used calibration method for a tri-axial field sensor is based on ellipsoid fitting, which has no requirement for external references. However, the self-calibration based on ellipsoid fitting is unable to determine and compensate the mutual misalignment between different sensors in a multi-sensor system. Therefore, a novel calibration method that employs the invariance of the dot product of two constant vectors is introduced in this paper. The proposed method, which is named dot product invariance method, brings a complete solution for the error model of tri-axial field sensors, and can solve the problem of alignment in a multi-sensor system. Its effectiveness and superiority over the ellipsoid fitting method are illustrated by numerical simulations, and its application on a digital magnetic compass shows significant enhancement of the heading accuracy. (paper)

  12. In situ calibration of inductively coupled plasma-atomic emission and mass spectroscopy

    Science.gov (United States)

    Braymen, Steven D.

    1996-06-11

    A method and apparatus for in situ addition calibration of an inductively coupled plasma atomic emission spectrometer or mass spectrometer using a precision gas metering valve to introduce a volatile calibration gas of an element of interest directly into an aerosol particle stream. The present situ calibration technique is suitable for various remote, on-site sampling systems such as laser ablation or nebulization.

  13. A temperature and pressure controlled calibration system for pressure sensors

    Science.gov (United States)

    Chapman, John J.; Kahng, Seun K.

    1989-01-01

    A data acquisition and experiment control system capable of simulating temperatures from -184 to +220 C and pressures either absolute or differential from 0 to 344.74 kPa is developed to characterize silicon pressure sensor response to temperature and pressure. System software is described that includes sensor data acquisition, algorithms for numerically derived thermal offset and sensitivity correction, and operation of the environmental chamber and pressure standard. This system is shown to be capable of computer interfaced cryogenic testing to within 1 C and 34.47 Pa of single channel or multiplexed arrays of silicon pressure sensors.

  14. Calibrating a combined energy systems analysis and controller design method with empirical data

    International Nuclear Information System (INIS)

    Murphy, Gavin Bruce; Counsell, John; Allison, John; Brindley, Joseph

    2013-01-01

    The drive towards low carbon constructions has seen buildings increasingly utilise many different energy systems simultaneously to control the human comfort of the indoor environment; such as ventilation with heat recovery, various heating solutions and applications of renewable energy. This paper describes a dynamic modelling and simulation method (IDEAS – Inverse Dynamics based Energy Assessment and Simulation) for analysing the energy utilisation of a building and its complex servicing systems. The IDEAS case study presented in this paper is based upon small perturbation theory and can be used for the analysis of the performance of complex energy systems and also for the design of smart control systems. This paper presents a process of how any dynamic model can be calibrated against a more empirical based data model, in this case the UK Government's SAP (Standard Assessment Procedure). The research targets of this work are building simulation experts for analysing the energy use of a building and also control engineers to assist in the design of smart control systems for dwellings. The calibration process presented is transferable and has applications for simulation experts to assist in calibrating any dynamic building simulation method with an empirical based method. - Highlights: • Presentation of an energy systems analysis method for assessing the energy utilisation of buildings and their complex servicing systems. • An inverse dynamics based controller design method is detailed. • Method of how a dynamic model can be calibrated with an empirical based model

  15. High precision, low disturbance calibration of the High Voltage system of the CMS Barrel Electromagnetic Calorimeter

    CERN Document Server

    Fasanella, Giuseppe

    2017-01-01

    The CMS Electromagnetic Calorimeter utilizes scintillating lead tungstate crystals, with avalanche photodiodes (APD) as photo-detectors in the barrel part. 1224 HV channels bias groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3pct/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  16. High precision, low disturbance calibration of the High Voltage system of the CMS Barrel Electromagnetic Calorimeter

    CERN Document Server

    Fasanella, Giuseppe

    2016-01-01

    The CMS Electromagnetic Calorimeter utilizes scintillating lead tungstate crystals, with avalanche photodiodes (APD) as photo-detectors in the barrel part. 1224 HV channels bias groups of 50 APD pairs, each at a voltage of about 380 V. The APD gain dependence on the voltage is 3pct/V. A stability of better than 60 mV is needed to have negligible impact on the calorimeter energy resolution. Until 2015 manual calibrations were performed yearly. A new calibration system was deployed recently, which satisfies the requirement of low disturbance and high precision. The system is discussed in detail and first operational experience is presented.

  17. Development report: Automatic System Test and Calibration (ASTAC) equipment

    Science.gov (United States)

    Thoren, R. J.

    1981-01-01

    A microcomputer based automatic test system was developed for the daily performance monitoring of wind energy system time domain (WEST) analyzer. The test system consists of a microprocessor based controller and hybrid interface unit which are used for inputing prescribed test signals into all WEST subsystems and for monitoring WEST responses to these signals. Performance is compared to theoretically correct performance levels calculated off line on a large general purpose digital computer. Results are displayed on a cathode ray tube or are available from a line printer. Excessive drift and/or lack of repeatability of the high speed analog sections within WEST is easily detected and the malfunctioning hardware identified using this system.

  18. Performance of dichromate dosimetry systems in calibration and dose intercomparison

    International Nuclear Information System (INIS)

    Bof, E.S.; Smolko, E.

    1999-01-01

    This report presents the results of the High Dose Dosimetry Laboratory of Argentina during ten years of international intercomparisons for high dose with the International Dose Assurance Service (IDAS) of the IAEA, using the standard high dose dichromate dosimetry system, and the results of a high dose intercomparison regional exercise in which our Laboratory acted as a reference laboratory, using the standard high dose and low dose dichromate dosimetry system. (author)

  19. Precision alignment and calibration of optical systems using computer generated holograms

    Science.gov (United States)

    Coyle, Laura Elizabeth

    As techniques for manufacturing and metrology advance, optical systems are being designed with more complexity than ever before. Given these prescriptions, alignment and calibration can be a limiting factor in their final performance. Computer generated holograms (CGHs) have several unique properties that make them powerful tools for meeting these demanding tolerances. This work will present three novel methods for alignment and calibration of optical systems using computer generated holograms. Alignment methods using CGHs require that the optical wavefront created by the CGH be related to a mechanical datum to locate it space. An overview of existing methods is provided as background, then two new alignment methods are discussed in detail. In the first method, the CGH contact Ball Alignment Tool (CBAT) is used to align a ball or sphere mounted retroreflector (SMR) to a Fresnel zone plate pattern with micron level accuracy. The ball is bonded directly onto the CGH substrate and provides permanent, accurate registration between the optical wavefront and a mechanical reference to locate the CGH in space. A prototype CBAT was built and used to align and bond an SMR to a CGH. In the second method, CGH references are used to align axi-symmetric optics in four degrees of freedom with low uncertainty and real time feedback. The CGHs create simultaneous 3D optical references where the zero order reflection sets tilt and the first diffracted order sets centration. The flexibility of the CGH design can be used to accommodate a wide variety of optical systems and maximize sensitivity to misalignments. A 2-CGH prototype system was aligned multiplied times and the alignment uncertainty was quantified and compared to an error model. Finally, an enhanced calibration method is presented. It uses multiple perturbed measurements of a master sphere to improve the calibration of CGH-based Fizeau interferometers ultimately measuring aspheric test surfaces. The improvement in the

  20. SU-E-J-47: Development of a High-Precision, Image-Guided Radiotherapy, Multi- Purpose Radiation Isocenter Quality-Assurance Calibration and Checking System

    International Nuclear Information System (INIS)

    Liu, C; Yan, G; Helmig, R; Lebron, S; Kahler, D

    2014-01-01

    Purpose: To develop a system that can define the radiation isocenter and correlate this information with couch coordinates, laser alignment, optical distance indicator (ODI) settings, optical tracking system (OTS) calibrations, and mechanical isocenter walkout. Methods: Our team developed a multi-adapter, multi-purpose quality assurance (QA) and calibration device that uses an electronic portal imaging device (EPID) and in-house image-processing software to define the radiation isocenter, thereby allowing linear accelerator (Linac) components to be verified and calibrated. Motivated by the concept that each Linac component related to patient setup for image-guided radiotherapy based on cone-beam CT should be calibrated with respect to the radiation isocenter, we designed multiple concentric adapters of various materials and shapes to meet the needs of MV and KV radiation isocenter definition, laser alignment, and OTS calibration. The phantom's ability to accurately define the radiation isocenter was validated on 4 Elekta Linacs using a commercial ball bearing (BB) phantom as a reference. Radiation isocenter walkout and the accuracy of couch coordinates, ODI, and OTS were then quantified with the device. Results: The device was able to define the radiation isocenter within 0.3 mm. Radiation isocenter walkout was within ±1 mm at 4 cardinal angles. By switching adapters, we identified that the accuracy of the couch position digital readout, ODI, OTS, and mechanical isocenter walkout was within sub-mm. Conclusion: This multi-adapter, multi-purpose isocenter phantom can be used to accurately define the radiation isocenter and represents a potential paradigm shift in Linac QA. Moreover, multiple concentric adapters allowed for sub-mm accuracy for the other relevant components. This intuitive and user-friendly design is currently patent pending

  1. Laser cutting system in bridge fabricating line; Kyoryo seisaku line ni okeru laser no setsudan system

    Energy Technology Data Exchange (ETDEWEB)

    Kitaguchi, Y.; Yokotani, K. [Hitachi Zosen Corp., Osaka (Japan)

    1994-11-01

    This paper describes the laser cutting system established at a new advanced plant that was constructed by Hitachi Shipbuilding and Engineering Co., Ltd. in 1993. At the plant, the cutting line consists of four NC cutting lines: the plasma cutting machine, gas cutting machine, frame planer, and laser cutting machine. The laser cutting machine is used to cut complex shapes of relatively thin (6 - 16 mm) materials with high accuracy. The machine consists of a 3 kW CO2 laser oscillator mounted gantry type NC cutter and a slat conveyor of about 30 m long, with the maximum cutting width of 3.6 m. The NC cutting machine is provided with the automatic printing function using NC data, marking function, scheduled operation function, steel plate detector, and coordinate rotation function, etc. These functions enable unattended operation of the machine to cut multiple materials. This NC laser cutting line has the same performance data collection function for data during the operating time as other production lines. Therefore, the NC laser cutting line can be subjected to the realtime centralized control together with the other lines. All these technologies have provided high accuracy and efficiency for production as well as an environment in which many female operators can successfully work. 10 figs., 4 tabs.

  2. Geometrical calibration television measuring systems with solid state photodetectors

    Science.gov (United States)

    Matiouchenko, V. G.; Strakhov, V. V.; Zhirkov, A. O.

    2000-11-01

    The various optical measuring methods for deriving information about the size and form of objects are now used in difference branches- mechanical engineering, medicine, art, criminalistics. Measuring by means of the digital television systems is one of these methods. The development of this direction is promoted by occurrence on the market of various types and costs small-sized television cameras and frame grabbers. There are many television measuring systems using the expensive cameras, but accuracy performances of low cost cameras are also interested for the system developers. For this reason inexpensive mountingless camera SK1004CP (format 1/3', cost up to 40$) and frame grabber Aver2000 were used in experiments.

  3. Absolute calibration of in vivo measurement systems using magnetic resonance imaging and Monte Carlo computations

    International Nuclear Information System (INIS)

    Mallett, M.W.

    1991-01-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. This method uses magnetic resonance imaging (MRI) to determine the anatomical makeup of an individual. A new MRI technique is also employed that is capable of resolving the fat and water content of the human tissue. This anatomical and biochemical information is used to model a mathematical phantom. Monte Carlo methods are then used to simulate the transport of radiation throughout the phantom. By modeling the detection equipment of the in vivo measurement system into the code, calibration factors are generated that are specific to the individual. Furthermore, this method eliminates the need for surrogate human structures in the calibration process. A demonstration of the proposed method is being performed using a fat/water matrix

  4. [Conservative calibration of a clearance monitor system for waste material from nuclear medicine].

    Science.gov (United States)

    Wanke, Carsten; Geworski, Lilli

    2014-09-01

    Clearance monitor systems are used for gross gamma measurements of waste potentially contaminated with radioactivity. These measurements are to make sure that legal requirements, e.g. clearance criteria according to the german radiation protection ordinance, are met. This means that measurement results may overestimate, but must not underestimate the true values. This paper describes a pragmatic way using a calibrated Cs-137 point source to generate a conservative calibration for the clearance monitor system used in the Medizinische Hochschule Hannover (MHH). The most important nuclides used in nuclear medicine are considered. The measurement result reliably overestimates the true value of the activity present in the waste. The calibration is compliant with the demands for conservativity and traceability to national standards. Copyright © 2014. Published by Elsevier GmbH.

  5. Absolute gain calibration system for the 349-pixel imaging element of the tactic telescope array

    International Nuclear Information System (INIS)

    Tickoo, A.K.; Dhar, V.K.; Venugopal, K.; Kaul, S.K.; Koul, R.; Bhatt, N.; Goyal, H.C.; Bhat, C.L.

    2001-01-01

    The imaging Element of the 4-element TACTIC telescope array has been in operation at Mt. Abu since 1997, for carrying detailed investigations of gamma-ray sources in the TeV energy range. In order to characterize the progenitor particle (Gamma-ray/cosmic-ray), a relative gain calibration system, based on a high intensity LED, has been in operation. However, for calorimetric purposes, an absolute gain calibration system is necessary and has been developed for an on-line calibration of 4 out of 349-pixels of its imaging camera, using 241 Am based light pulsers. The details of the experimental set-up and the results obtained so far are presented in this paper. (author)

  6. Calibration of the Accuscan II IN Vivo System for High Energy Lung Counting

    Energy Technology Data Exchange (ETDEWEB)

    Ovard R. Perry; David L. Georgeson

    2011-07-01

    This report describes the April 2011 calibration of the Accuscan II HpGe In Vivo system for high energy lung counting. The source used for the calibration was a NIST traceable lung set manufactured at the University of Cincinnati UCLL43AMEU & UCSL43AMEU containing Am-241 and Eu-152 with energies from 26 keV to 1408 keV. The lung set was used in conjunction with a Realistic Torso phantom. The phantom was placed on the RMC II counting table (with pins removed) between the v-ridges on the backwall of the Accuscan II counter. The top of the detector housing was positioned perpendicular to the junction of the phantom clavicle with the sternum. This position places the approximate center line of the detector housing with the center of the lungs. The energy and efficiency calibrations were performed using a Realistic Torso phantom (Appendix I) and the University of Cincinnati lung set. This report includes an overview introduction and records for the energy/FWHM and efficiency calibration including performance verification and validation counting. The Accuscan II system was successfully calibrated for high energy lung counting and verified in accordance with ANSI/HPS N13.30-1996 criteria.

  7. Calibration of the Accuscan II In Vivo System for I-131 Thyroid Counting

    Energy Technology Data Exchange (ETDEWEB)

    Orval R. Perry; David L. Georgeson

    2011-07-01

    This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-131 thyroid counting. The source used for the calibration was an Analytics mixed gamma source 82834-121 distributed in an epoxy matrix in a Wheaton Liquid Scintillation Vial with energies from 88.0 keV to 1836.1 keV. The center of the detectors was position 64-feet from the vault floor. This position places the approximate center line of the detectors at the center line of the source in the thyroid tube. The calibration was performed using an RMC II phantom (Appendix J). Validation testing was performed using a Ba-133 source and an ANSI N44.3 Phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibrations including verification counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-131 and verified in accordance with ANSI/HPS N13.30-1996 criteria.

  8. Calibration of the Accuscan II In Vivo System for I-125 Thyroid Counting

    Energy Technology Data Exchange (ETDEWEB)

    Ovard R. Perry; David L. Georgeson

    2011-07-01

    This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-125 thyroid counting. The source used for the calibration was a DOE manufactured Am-241/Eu-152 source contained in a 22 ml vial BEA Am-241/Eu-152 RMC II-1 with energies from 26 keV to 344 keV. The center of the detector housing was positioned 64 inches from the vault floor. This position places the approximate center line of the detector housing at the center line of the source in the phantom thyroid tube. The energy and efficiency calibration were performed using an RMC II phantom (Appendix J). Performance testing was conducted using source BEA Am-241/Eu-152 RMC II-1 and Validation testing was performed using an I-125 source in a 30 ml vial (I-125 BEA Thyroid 002) and an ANSI N44.3 phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibration including performance verification and validation counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-125 and verified in accordance with ANSI/HPS N13.30-1996 criteria.

  9. Diode-laser-illuminated automotive lamp systems

    Science.gov (United States)

    Marinelli, Michael A.; Remillard, Jeffrey T.

    1998-05-01

    We have utilized the high brightness of state-of-the-art diode laser sources, and a variety of emerging optical technologies to develop a new class of thin, uniquely styled automotive brake and signal lamps. Using optics based on thin (5 mm) plastic sheets, these lamps provide appearance and functional advantages not attainable with traditional automotive lighting systems. The light is coupled into the sheets using a 1 mm diameter glass fiber, and manipulated using refraction and reflection from edges, surfaces, and shaped cut-outs. Light can be extracted with an efficiency of approximately 50% and formed into a luminance distribution that meets the Society of Automotive Engineers (SAE) photometric requirements. Prototype lamps using these optics have been constructed and are less than one inch in thickness. Thin lamps reduce sheet metal costs, complexity, material usage, weight, and allow for increased trunk volume. In addition, these optics enhance lamp design flexibility. When the lamps are not energized, they can appear body colored, and when lighted, the brightness distribution across the lamp can be uniform or structured. A diode laser based brake lamp consumes seven times less electrical power than one using an incandescent source and has instant on capability. Also, diode lasers have the potential to be 10-year/150,000 mile light sources.

  10. Long life gas laser system and method

    International Nuclear Information System (INIS)

    Hochuli, E.E.

    1975-01-01

    A long life gas discharge laser having an improved self-repairing cathode system is described. In a specific embodiment, water vapor having a partial pressure below about 10 -5 torr incorporated in a molecular sieve is used to provide impurities (in this case water vapor) for repairing the cathode surface by regenerating the oxide surface and/or preventing same from deteriorating. Other impurities may be incorporated in the molecular sieve such as hydrogen, oxygen, for example. In some cases CO 2 may be used. This application includes material disclosed in a paper entitled ''Continuation of the Investigation into Material Properties Affecting the Frequency Stability and Reliability of He-Ne Laser Structures'' submitted to the Office of Naval Research dated June 1972 by the inventor hereof and also a paper entitled ''Investigations of the Long Term Frequency Stability of Stable Laser Structures'' Progress Report for ONR Contract N00014-67-A-D239-0016 July 1972 by the inventor hereof. A royalty free license is hereby granted to the United States for use of the invention for all government purposes. (auth)

  11. Generic precise augmented reality guiding system and its calibration method based on 3D virtual model.

    Science.gov (United States)

    Liu, Miao; Yang, Shourui; Wang, Zhangying; Huang, Shujun; Liu, Yue; Niu, Zhenqi; Zhang, Xiaoxuan; Zhu, Jigui; Zhang, Zonghua

    2016-05-30

    Augmented reality system can be applied to provide precise guidance for various kinds of manual works. The adaptability and guiding accuracy of such systems are decided by the computational model and the corresponding calibration method. In this paper, a novel type of augmented reality guiding system and the corresponding designing scheme are proposed. Guided by external positioning equipment, the proposed system can achieve high relative indication accuracy in a large working space. Meanwhile, the proposed system is realized with a digital projector and the general back projection model is derived with geometry relationship between digitized 3D model and the projector in free space. The corresponding calibration method is also designed for the proposed system to obtain the parameters of projector. To validate the proposed back projection model, the coordinate data collected by a 3D positioning equipment is used to calculate and optimize the extrinsic parameters. The final projecting indication accuracy of the system is verified with subpixel pattern projecting technique.

  12. Energy storage and power conditioning system for the Shiva laser

    International Nuclear Information System (INIS)

    Allen, G.R.; Gagnon, W.L.; Rupert, P.R.; Trenholme, J.B.

    1975-01-01

    An optimal energy delivery system for the world's largest glass laser system has been designed based on computer modeling and operation of laser hardware. Components of the system have been tested on operating lasers at LLL. The Shiva system is now under construction and will be completed in 1977. The energy supply described here will provide cost-effective, reliable power and facilitate the gathering of data in pursuit of controlled thermonuclear reactions

  13. Development of AVLIS dye laser system

    International Nuclear Information System (INIS)

    Sugiyama, Akira; Nakayama, Tsuyoshi; Kato, Masaaki; Arisawa, Takashi

    1995-01-01

    CVL pumped single mode dye laser was performed. It was found that pressure tuning has some excellent feature in comparison to mechanical tuning in dye laser frequency control. For evaluation of dye laser amplifier, two-dimensional rate equation was proposed. Calculated data by this equation agreed with experimental data in large diameter input dye laser beam condition. (author)

  14. CONFOCAL MICROSCOPY SYSTEM PERFORMANCE: LASER POWER MEASUREMENTS

    Science.gov (United States)

    Laser power abstract The reliability of the confocal laser-scanning microscope (CLSM) to obtain intensity measurements and quantify fluorescence data is dependent on using a correctly aligned machine that contains a stable laser power. The laser power test appears to be one ...

  15. Self-Calibrating, Variable-Flow Pumping System

    Science.gov (United States)

    Walls, Joe T.

    1994-01-01

    Pumping system provides accurate, controlled flows of two chemical liquids mixed in spray head and react to form rigid or flexible polyurethane or polyisocyanurate foam. Compatible with currently used polyurethane-based coating materials and gas-bubble-forming agents (called "blowing agents" in industry) and expected to be compatible with materials that used in near future. Handles environmentally acceptable substitutes for chlorofluorocarbon foaming agents.

  16. Development and calibration of an accurate 6-degree-of-freedom measurement system with total station

    International Nuclear Information System (INIS)

    Gao, Yang; Lin, Jiarui; Yang, Linghui; Zhu, Jigui

    2016-01-01

    To meet the demand of high-accuracy, long-range and portable use in large-scale metrology for pose measurement, this paper develops a 6-degree-of-freedom (6-DOF) measurement system based on total station by utilizing its advantages of long range and relative high accuracy. The cooperative target sensor, which is mainly composed of a pinhole prism, an industrial lens, a camera and a biaxial inclinometer, is designed to be portable in use. Subsequently, a precise mathematical model is proposed from the input variables observed by total station, imaging system and inclinometer to the output six pose variables. The model must be calibrated in two levels: the intrinsic parameters of imaging system, and the rotation matrix between coordinate systems of the camera and the inclinometer. Then corresponding approaches are presented. For the first level, we introduce a precise two-axis rotary table as a calibration reference. And for the second level, we propose a calibration method by varying the pose of a rigid body with the target sensor and a reference prism on it. Finally, through simulations and various experiments, the feasibilities of the measurement model and calibration methods are validated, and the measurement accuracy of the system is evaluated. (paper)

  17. Recent laser physics results on power balance and frequency conversion with the Phebus laser system

    International Nuclear Information System (INIS)

    Thiell, G.; Paye, J.; Graillot, H.; Mathieu, F.; Boscheron, A.; Reynier, F.; Estraillier, P.; Bruneau, J.L.

    1995-01-01

    The Phebus laser system has been mainly devoted to plasma physics experiments such as implosion and hydrodynamical instability studies since it was completed in 1985. But during the last two years, the three Phebus beamlines (2 main beams and a backlighter beam) are also utilized to perform some laser physics studies in view of the Megajoule laser project. The goal of the laser physics experiments conducted at the Phebus facility in 1994--1995 is to validate some design issues of the Megajoule Laser project concerning namely power balance and frequency conversion

  18. TIMED solar EUV experiment: preflight calibration results for the XUV photometer system

    Science.gov (United States)

    Woods, Thomas N.; Rodgers, Erica M.; Bailey, Scott M.; Eparvier, Francis G.; Ucker, Gregory J.

    1999-10-01

    The Solar EUV Experiment (SEE) on the NASA Thermosphere, Ionosphere, and Mesosphere Energetics and Dynamics (TIMED) mission will measure the solar vacuum ultraviolet (VUV) spectral irradiance from 0.1 to 200 nm. To cover this wide spectral range two different types of instruments are used: a grating spectrograph for spectra between 25 and 200 nm with a spectral resolution of 0.4 nm and a set of silicon soft x-ray (XUV) photodiodes with thin film filters as broadband photometers between 0.1 and 35 nm with individual bandpasses of about 5 nm. The grating spectrograph is called the EUV Grating Spectrograph (EGS), and it consists of a normal- incidence, concave diffraction grating used in a Rowland spectrograph configuration with a 64 X 1024 array CODACON detector. The primary calibrations for the EGS are done using the National Institute for Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF-III) in Gaithersburg, Maryland. In addition, detector sensitivity and image quality, the grating scattered light, the grating higher order contributions, and the sun sensor field of view are characterized in the LASP calibration laboratory. The XUV photodiodes are called the XUV Photometer System (XPS), and the XPS includes 12 photodiodes with thin film filters deposited directly on the silicon photodiodes' top surface. The sensitivities of the XUV photodiodes are calibrated at both the NIST SURF-III and the Physikalisch-Technische Bundesanstalt (PTB) electron storage ring called BESSY. The other XPS calibrations, namely the electronics linearity and field of view maps, are performed in the LASP calibration laboratory. The XPS and solar sensor pre-flight calibration results are primarily discussed as the EGS calibrations at SURF-III have not yet been performed.

  19. Quasi-static displacement calibration system for a "Violin-Mode" shadow-sensor intended for Gravitational Wave detector suspensions

    Science.gov (United States)

    Lockerbie, N. A.; Tokmakov, K. V.

    2014-10-01

    This paper describes the design of, and results from, a calibration system for optical linear displacement (shadow) sensors. The shadow sensors were designed to detect "Violin-Mode" (VM) resonances in the 0.4 mm diameter silica fibre suspensions of the test masses/mirrors of Advanced Laser Interferometer Gravitational Wave Observatory gravitational wave interferometers. Each sensor illuminated the fibre under test, so as to cast its narrow shadow onto a "synthesized split photodiode" detector, the shadow falling over adjacent edges of the paired photodiodes. The apparatus described here translated a vertically orientated silica test fibre horizontally through a collimated Near InfraRed illuminating beam, whilst simultaneously capturing the separate DC "shadow notch" outputs from each of the paired split photodiode detectors. As the ratio of AC to DC photocurrent sensitivities to displacement was known, a calibration of the DC response to quasi-static shadow displacement allowed the required AC sensitivity to vibrational displacement to be found. Special techniques are described for generating the required constant scan rate for the test fibre using a DC motor-driven stage, for removing "jitter" at such low translation rates from a linear magnetic encoder, and so for capturing the two shadow-notch signals at each micrometre of the test fibre's travel. Calibration, across the four detectors of this work, gave a vibrational responsivity in voltage terms of (9.45 ± 1.20) MV (rms)/m, yielding a VM displacement sensitivity of (69 ± 13) pm (rms)/√Hz, at 500 Hz, over the required measuring span of ±0.1 mm.

  20. Model calibration of a variable refrigerant flow system with a dedicated outdoor air system: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dongsu [Mississippi State Univ., Starkville, MS (United States); Cox, Sam J. [Mississippi State Univ., Starkville, MS (United States); Cho, Heejin [Mississippi State Univ., Starkville, MS (United States); Im, Piljae [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-10-16

    With increased use of variable refrigerant flow (VRF) systems in the U.S. building sector, interests in capability and rationality of various building energy modeling tools to simulate VRF systems are rising. This paper presents the detailed procedures for model calibration of a VRF system with a dedicated outdoor air system (DOAS) by comparing to detailed measured data from an occupancy emulated small office building. The building energy model is first developed based on as-built drawings, and building and system characteristics available. The whole building energy modeling tool used for the study is U.S. DOE’s EnergyPlus version 8.1. The initial model is, then, calibrated with the hourly measured data from the target building and VRF-DOAS system. In a detailed calibration procedures of the VRF-DOAS, the original EnergyPlus source code is modified to enable the modeling of the specific VRF-DOAS installed in the building. After a proper calibration during cooling and heating seasons, the VRF-DOAS model can reasonably predict the performance of the actual VRF-DOAS system based on the criteria from ASHRAE Guideline 14-2014. The calibration results show that hourly CV-RMSE and NMBE would be 15.7% and 3.8%, respectively, which is deemed to be calibrated. As a result, the whole-building energy usage after calibration of the VRF-DOAS model is 1.9% (78.8 kWh) lower than that of the measurements during comparison period.

  1. Development of an energy selector system for laser-driven proton beam applications

    Energy Technology Data Exchange (ETDEWEB)

    Scuderi, V., E-mail: scuderiv@lns.infn.it [Department of Experimental Program at ELI-Beamlines, Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Bijan Jia, S. [Ferdowsi University of Mashhad, Azadi Square, Mashhad (Iran, Islamic Republic of); Carpinelli, M. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Cirrone, G.A.P. [Department of Experimental Program at ELI-Beamlines, Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Cuttone, G. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Korn, G. [Department of Experimental Program at ELI-Beamlines, Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Licciardello, T. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Maggiore, M. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Viale dell' Universit 2, Legnaro (Pd) (Italy); Margarone, D. [Department of Experimental Program at ELI-Beamlines, Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Pisciotta, P.; Romano, F. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Schillaci, F. [Department of Experimental Program at ELI-Beamlines, Institute of Physics of the ASCR, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Stancampiano, C. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); and others

    2014-03-11

    Nowadays, laser-driven proton beams generated by the interaction of high power lasers with solid targets represent a fascinating attraction in the field of the new acceleration techniques. These beams can be potentially accelerated up to hundreds of MeV and, therefore, they can represent a promising opportunity for medical applications. Laser-accelerated proton beams typically show high flux (up to 10{sup 11} particles per bunch), very short temporal profile (ps), broad energy spectra and poor reproducibility. In order to overcome these limitations, these beams have be controlled and transported by means of a proper beam handling system. Furthermore, suitable dosimetric diagnostic systems must be developed and tested. In the framework of the ELIMED project, we started to design a dedicated beam transport line and we have developed a first prototype of a beam line key-element: an Energy Selector System (ESS). It is based on permanent dipoles, capable to control and select in energy laser-accelerated proton beams. Monte Carlo simulations and some preliminary experimental tests have been already performed to characterize the device. A calibration of the ESS system with a conventional proton beam will be performed in September at the LNS in Catania. Moreover, an experimental campaign with laser-driven proton beam at the Centre for Plasma Physics, Queens University in Belfast is already scheduled and will be completed within 2014.

  2. Lasers and power systems for inertial confinement fusion reactors

    International Nuclear Information System (INIS)

    Stark, E.E. Jr.

    1978-01-01

    After discussing the role of lasers in ICF and the candidate lasers, several important areas of technology requirements are discussed. These include the beam transport system, the pulsed power system and the gas flow system. The system requirements, state of the art, as well as needs and prospects for new technology developments are given. Other technology issues and promising developments are described briefly

  3. Calibration Curve of Neutron Moisture Meter for Sandy Soil under Drip Irrigation System

    International Nuclear Information System (INIS)

    Mohammad, Abd El- Moniem M.; Gendy, R. W.; Bedaiwy, M. N.

    2004-01-01

    The aim of this work is to construct a neutron calibration curve in order to be able to use the neutron probe in sandy soils under drip irrigation systems. The experimental work was conducted at the Soil and Water Department of the Nuclear Research Center, Atomic Energy Authority. Three replicates were used along the lateral lines of the drip irrigation system. For each dripper, ten neutron access tubes were installed to 100-cm depth at distances of 5, 15 and 25 cm from the dripper location around the drippers on the lateral line, as well as between lateral lines. The neutron calibrations were determined at 30, 45, and 60-cm depths. Determining coefficients as well as t-test in pairs were employed to detect the accuracy of the calibrations. Results indicated that in order for the neutron calibration curve to express the whole wet area around the emitter; three-access tubes must be installed at distances of 5, 15, and 25 cm from the emitter. This calibration curve will be correlating the average count ratio (CR) at the studied soil depth of the three locations (5, 15, and 25-cm distances from the emitter) to the average moisture content (θ) for this soil depth of the entire wetted area. This procedure should be repeated at different times in order to obtain different θ and C.R values, so that the regression equation of calibration curve at this soil depth can be obtained. To determine the soil moisture content, the average CR of the three locations must be taken and substituted into the regression equation representing the neutron calibration curve. Results taken from access tubes placed at distances of 15 cm from the emitter, showed good agreement with the average calibration curve both for the 45- and the 60-cm depths, suggesting that the 15-cm distance may provide a suitable substitute for the simultaneous use of the three different distances of 5, 15 and 25 cm. However, the obtained results show also that the neutron calibration curves of the 30-cm depth for

  4. The Improved NRL Tropical Cyclone Monitoring System with a Unified Microwave Brightness Temperature Calibration Scheme

    Directory of Open Access Journals (Sweden)

    Song Yang

    2014-05-01

    Full Text Available The near real-time NRL global tropical cyclone (TC monitoring system based on multiple satellite passive microwave (PMW sensors is improved with a new inter-sensor calibration scheme to correct the biases caused by differences in these sensor’s high frequency channels. Since the PMW sensor 89 GHz channel is used in multiple current and near future operational and research satellites, a unified scheme to calibrate all satellite PMW sensor’s ice scattering channels to a common 89 GHz is created so that their brightness temperatures (TBs will be consistent and permit more accurate manual and automated analyses. In order to develop a physically consistent calibration scheme, cloud resolving model simulations of a squall line system over the west Pacific coast and hurricane Bonnie in the Atlantic Ocean are applied to simulate the views from different PMW sensors. To clarify the complicated TB biases due to the competing nature of scattering and emission effects, a four-cloud based calibration scheme is developed (rain, non-rain, light rain, and cloudy. This new physically consistent inter-sensor calibration scheme is then evaluated with the synthetic TBs of hurricane Bonnie and a squall line as well as observed TCs. Results demonstrate the large TB biases up to 13 K for heavy rain situations before calibration between TMI and AMSR-E are reduced to less than 3 K after calibration. The comparison stats show that the overall bias and RMSE are reduced by 74% and 66% for hurricane Bonnie, and 98% and 85% for squall lines, respectively. For the observed hurricane Igor, the bias and RMSE decrease 41% and 25% respectively. This study demonstrates the importance of TB calibrations between PMW sensors in order to systematically monitor the global TC life cycles in terms of intensity, inner core structure and convective organization. A physics-based calibration scheme on TC’s TB corrections developed in this study is able to significantly reduce the

  5. Development of YAG laser cutting system for decommissioning nuclear equipments

    International Nuclear Information System (INIS)

    Kasai, Takeshi; Nitta, Kazuhiko; Hosoda, Hiroshi.

    1995-01-01

    Technology of remote controlled cutting and reduction of generative secondary products have been required to the cutting system for decommissioning nuclear equipments. At a point of view that laser cutting technology by use of a Nd:YAG laser is effective, we have developed the laser cutting machine and carried out cutting tests for several stainless steel plates. As a result, the stainless steel plate with a thickness of 22mm could be cut by using an optical fiber which can flexibly propagate laser power, and possibility of application of this laser cutting system to decommissioning nuclear equipments was verified. (author)

  6. Development of YAG laser cutting system for decommissioning nuclear equipments

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Takeshi [Fuji Electric Co. Research and Development Ltd., Yokosuka, Kanagawa (Japan); Nitta, Kazuhiko; Hosoda, Hiroshi

    1995-07-01

    Technology of remote controlled cutting and reduction of generative secondary products have been required to the cutting system for decommissioning nuclear equipments. At a point of view that laser cutting technology by use of a Nd:YAG laser is effective, we have developed the laser cutting machine and carried out cutting tests for several stainless steel plates. As a result, the stainless steel plate with a thickness of 22mm could be cut by using an optical fiber which can flexibly propagate laser power, and possibility of application of this laser cutting system to decommissioning nuclear equipments was verified. (author).

  7. Laser system for a subpicosecond electron linac

    International Nuclear Information System (INIS)

    Crowell, R. A.

    1998-01-01

    At the Argonne Chemistry Division efforts are underway to develop a sub-picosecond electron beam pulse radiolysis facility for chemical studies. The target output of the accelerator is to generate electron pulses that can be adjusted from 3nC in .6ps to 100nC in 45ps. In conjunction with development of the accelerator a state-of-the-art ultrafast laser system is under construction that will drive the linac's photocathode and provide probe pulses that are tunable from the UV to IR spectral regions

  8. CALIS—A CALibration Insertion System for the DarkSide-50 dark matter search experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnes, P.; Albuquerque, I. F. M.; Alexander, T.; Alton, A. K.; Asner, D. M.; Back, H. O.; Baldin, B.; Biery, K.; Bocci, V.; Bonfini, G.; Bonivento, W.; Bossa, M.; Bottino, B.; Brigatti, A.; Brodsky, J.; Budano, F.; Bussino, S.; Cadeddu, M.; Cadonati, L.; Cadoni, M.; Calaprice, F.; Canci, N.; Candela, A.; Caravati, M.; Cariello, M.; Carlini, M.; Catalanotti, S.; Cavalcante, P.; Chepurnov, A.; Cicalò, C.; Cocco, A. G.; Covone, G.; D' Angelo, D.; D' Incecco, M.; Davini, S.; Cecco, S. De; Deo, M. De; Vincenzi, M. De; Derbin, A.; Devoto, A.; Eusanio, F. Di; Pietro, G. Di; Dionisi, C.; Edkins, E.; Empl, A.; Fan, A.; Fiorillo, G.; Fomenko, K.; Forster, G.; Franco, D.; Gabriele, F.; Galbiati, C.; Giagu, S.; Giganti, C.; Giovanetti, G. K.; Goretti, A. M.; Granato, F.; Grandi, L.; Gromov, M.; Guan, M.; Guardincerri, Y.; Hackett, B. R.; Herner, K.; Hughes, D.; Humble, P.; Hungerford, E. V.; Ianni, Al.; Ianni, An.; James, I.; Johnson, T. N.; Jollet, C.; Keeter, K.; Kendziora, C. L.; Koh, G.; Korablev, D.; Korga, G.; Kubankin, A.; Li, X.; Lissia, M.; Loer, B.; Lombardi, P.; Longo, G.; Ma, Y.; Machado, A. A.; Machulin, I. N.; Mandarano, A.; Mari, S. M.; Maricic, J.; Marini, L.; Martoff, C. J.; Meregaglia, A.; Meyers, P. D.; Milincic, R.; Miller, J. D.; Montanari, D.; Monte, A.; Mount, B. J.; Muratova, V. N.; Musico, P.; Napolitano, J.; Agasson, A. Navrer; Odrowski, S.; Orsini, M.; Ortica, F.; Pagani, L.; Pallavicini, M.; Pantic, E.; Parmeggiano, S.; Pelczar, K.; Pelliccia, N.; Pocar, A.; Pordes, S.; Pugachev, D. A.; Qian, H.; Randle, K.; Ranucci, G.; Razeti, M.; Razeto, A.; Reinhold, B.; Renshaw, A. L.; Rescigno, M.; Riffard, Q.; Romani, A.; Rossi, B.; Rossi, N.; Rountree, D.; Sablone, D.; Saggese, P.; Saldanha, R.; Sands, W.; Savarese, C.; Schlitzer, B.; Segreto, E.; Semenov, D. A.; Shields, E.; Singh, P. N.; Skorokhvatov, M. D.; Smirnov, O.; Sotnikov, A.; Stanford, C.; Suvorov, Y.; Tartaglia, R.; Tatarowicz, J.; Testera, G.; Tonazzo, A.; Trinchese, P.; Unzhakov, E. V.; Verducci, M.; Vishneva, A.; Vogelaar, B.; Wada, M.; Walker, S.; Wang, H.; Wang, Y.; Watson, A. W.; Westerdale, S.; Wilhelmi, J.; Wojcik, M. M.; Xiang, Xi.; Xiao, X.; Xu, J.; Yang, C.; Zec, A.; Zhong, W.; Zhu, C.; Zuzel, G.

    2017-12-01

    This paper describes the design, fabrication, commissioning and use of a CALibration source Insertion System (CALIS) in the DarkSide-50 direct dark matter search experiment. CALIS deploys radioactive sources into the liquid scintillator veto to characterize the detector response and detection efficiency of the DarkSide-50 Liquid Argon Time Projection Chamber, and the surrounding 30 t organic liquid scintillator neutron veto. It was commissioned in September 2014 and has been used successfully in several gamma and neutron source campaigns since then. A description of the hardware and an excerpt of calibration analysis results are given below.

  9. A Quadratic Model with Nonpolynomial Terms for Remote Colorimetric Calibration of 3D Laser Scanner Data Based on Piecewise Cubic Hermite Polynomials

    Directory of Open Access Journals (Sweden)

    Alessandro Danielis

    2015-01-01

    Full Text Available The processing of intensity data from terrestrial laser scanners has attracted considerable attention in recent years. Accurate calibrated intensity could give added value for laser scanning campaigns, for example, in producing faithful 3D colour models of real targets and classifying easier and more reliable automatic tools. In cultural heritage area, the purely geometric information provided by the vast majority of currently available scanners is not enough for most applications, where indeed accurate colorimetric data is needed. This paper presents a remote calibration method for self-registered RGB colour data provided by a 3D tristimulus laser scanner prototype. Such distinguishing colour information opens new scenarios and problems for remote colorimetry. Using piecewise cubic Hermite polynomials, a quadratic model with nonpolynomial terms for reducing inaccuracies occurring in remote colour measurement is implemented. Colorimetric data recorded by the prototype on certified diffusive targets is processed for generating a remote Lambertian model used for assessing the accuracy of the proposed algorithm. Results concerning laser scanner digitizations of artworks are reported to confirm the effectiveness of the method.

  10. Development and performance of a calibration system for a large calorimeter array

    International Nuclear Information System (INIS)

    Arenton, M.; Dawson, J.; Ditzler, W.R.

    1982-01-01

    Experiment 609 at Fermilab is a study of the properties of high-p/sub t/ collisions using a large segmented hadron calorimeter. The calibration and monitoring of such a large calorimeter array is a difficult undertaking. This paper describes the systems developed by E609 for automatic monitoring of the phototube gains and performance of the associated electronics

  11. An Improved Calibration Method for a Rotating 2D LIDAR System

    Directory of Open Access Journals (Sweden)

    Yadan Zeng

    2018-02-01

    Full Text Available This paper presents an improved calibration method of a rotating two-dimensional light detection and ranging (R2D-LIDAR system, which can obtain the 3D scanning map of the surroundings. The proposed R2D-LIDAR system, composed of a 2D LIDAR and a rotating unit, is pervasively used in the field of robotics owing to its low cost and dense scanning data. Nevertheless, the R2D-LIDAR system must be calibrated before building the geometric model because there are assembled deviation and abrasion between the 2D LIDAR and the rotating unit. Hence, the calibration procedures should contain both the adjustment between the two devices and the bias of 2D LIDAR itself. The main purpose of this work is to resolve the 2D LIDAR bias issue with a flat plane based on the Levenberg–Marquardt (LM algorithm. Experimental results for the calibration of the R2D-LIDAR system prove the reliability of this strategy to accurately estimate sensor offsets with the error range from −15 mm to 15 mm for the performance of capturing scans.

  12. The GRAAL high resolution BGO calorimeter and its energy calibration and monitoring system

    International Nuclear Information System (INIS)

    Ghio, F.; Girolami, B.

    1997-07-01

    The authors describe the electromagnetic calorimeter built for the GRAAL apparatus at the ESRF. Its monitoring system is presented in detail. Result from tests and the performance obtained during the first GRAAL experiments are given. The energy calibration accuracy and stability reached is a small fraction of the intrinsic detector resolution

  13. An Improved Calibration Method for a Rotating 2D LIDAR System.

    Science.gov (United States)

    Zeng, Yadan; Yu, Heng; Dai, Houde; Song, Shuang; Lin, Mingqiang; Sun, Bo; Jiang, Wei; Meng, Max Q-H

    2018-02-07

    This paper presents an improved calibration method of a rotating two-dimensional light detection and ranging (R2D-LIDAR) system, which can obtain the 3D scanning map of the surroundings. The proposed R2D-LIDAR system, composed of a 2D LIDAR and a rotating unit, is pervasively used in the field of robotics owing to its low cost and dense scanning data. Nevertheless, the R2D-LIDAR system must be calibrated before building the geometric model because there are assembled deviation and abrasion between the 2D LIDAR and the rotating unit. Hence, the calibration procedures should contain both the adjustment between the two devices and the bias of 2D LIDAR itself. The main purpose of this work is to resolve the 2D LIDAR bias issue with a flat plane based on the Levenberg-Marquardt (LM) algorithm. Experimental results for the calibration of the R2D-LIDAR system prove the reliability of this strategy to accurately estimate sensor offsets with the error range from -15 mm to 15 mm for the performance of capturing scans.

  14. A Fast Calibration System for SiPM Based Scintillator HCAL Detector

    CERN Document Server

    Polak, I

    2015-01-01

    with mid-range a fixed-intensity light pulse. The full SiPM response function is cross-checked by varying the light intensity from zero to the saturation level. In calibration systems we developed, we concentrate especially on the aspect a high dynamic range of pre...

  15. Innovative Calibration Method for System Level Simulation Models of Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Ivo Prah

    2016-09-01

    Full Text Available The paper outlines a procedure for the computer-controlled calibration of the combined zero-dimensional (0D and one-dimensional (1D thermodynamic simulation model of a turbocharged internal combustion engine (ICE. The main purpose of the calibration is to determine input parameters of the simulation model in such a way as to achieve the smallest difference between the results of the measurements and the results of the numerical simulations with minimum consumption of the computing time. An innovative calibration methodology is based on a novel interaction between optimization methods and physically based methods of the selected ICE sub-systems. Therein physically based methods were used for steering the division of the integral ICE to several sub-models and for determining parameters of selected components considering their governing equations. Innovative multistage interaction between optimization methods and physically based methods allows, unlike the use of well-established methods that rely only on the optimization techniques, for successful calibration of a large number of input parameters with low time consumption. Therefore, the proposed method is suitable for efficient calibration of simulation models of advanced ICEs.

  16. The calibration procedure of the radiation monitoring system installed in radiation controlled area of KOMAC

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung-Kyun; Min, Yi-Sub; Park, Jeong-Min; Cho, Yong-Sub [Korea Atomic Energy Research Institute, Gyeongju (Korea, Republic of)

    2016-10-15

    The spaces, where these accelerators are installed, are defined as the radiation controlled area and the levels of the radiation in this area are monitored by the radiation monitoring system (RMS) to protect radiation workers and experiment users from the hazards of the ionizing radiation and the surface and air contamination tests are carried out periodically by the radiation secure team. The most of RMS instruments are installed in the accelerator building, where the 100-MeV proton linear accelerator is installed. All detectors of RMS should be calibrated every year to prove the reliability of RMS and almost all instruments for RMS was calibrated during this summer maintenance period of KOMAC this year. Almost all RMS instruments installed in KOMAC is calibrated between 2016-07-13 and 2016-08-24. As the calibration result, if the current reading value are within the 5% of the reference dose rate value, this RMS instrument can be used one more year. Otherwise, the detector of that RMS instrument should be repaired or replaced. The self-calibration certificate for each RMS instrument will be published only for the instrument to satisfy the condition.

  17. Error Analysis and Calibration Method of a Multiple Field-of-View Navigation System

    OpenAIRE

    Shi, Shuai; Zhao, Kaichun; You, Zheng; Ouyang, Chenguang; Cao, Yongkui; Wang, Zhenzhou

    2017-01-01

    The Multiple Field-of-view Navigation System (MFNS) is a spacecraft subsystem built to realize the autonomous navigation of the Spacecraft Inside Tiangong Space Station. This paper introduces the basics of the MFNS, including its architecture, mathematical model and analysis, and numerical simulation of system errors. According to the performance requirement of the MFNS, the calibration of both intrinsic and extrinsic parameters of the system is assumed to be essential and pivotal. Hence, a n...

  18. Automatic calibration and signal switching system for the particle beam fusion research data acquisition facility

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, W.B.

    1979-09-01

    This report describes both the hardware and software components of an automatic calibration and signal system (Autocal) for the data acquisition system for the Sandia particle beam fusion research accelerators Hydra, Proto I, and Proto II. The Autocal hardware consists of off-the-shelf commercial equipment. The various hardware components, special modifications and overall system configuration are described. Special software has been developed to support the Autocal hardware. Software operation and maintenance are described.

  19. Designing a Signal Conditioning System with Software Calibration for Resistor-feedback Patch Clamp Amplifier.

    Science.gov (United States)

    Hu, Gang; Zhu, Quanhui; Qu, Anlian

    2005-01-01

    In this paper, a programmable signal conditioning system based on software calibration for resistor-feedback patch clamp amplifier (PCA) has been described, this system is mainly composed of frequency correction, programmable gain and filter whose parameters are configured by software automatically to minimize the errors, A lab-designed data acquisition system (DAQ) is used to implement data collections and communications with PC. The laboratory test results show good agreement with design specifications.

  20. Automatic calibration and signal switching system for the particle beam fusion research data acquisition facility

    International Nuclear Information System (INIS)

    Boyer, W.B.

    1979-09-01

    This report describes both the hardware and software components of an automatic calibration and signal system (Autocal) for the data acquisition system for the Sandia particle beam fusion research accelerators Hydra, Proto I, and Proto II. The Autocal hardware consists of off-the-shelf commercial equipment. The various hardware components, special modifications and overall system configuration are described. Special software has been developed to support the Autocal hardware. Software operation and maintenance are described