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Sample records for coplanar fields metodo

  1. Printing Semiconductor-Insulator Polymer Bilayers for High-Performance Coplanar Field-Effect Transistors.

    Science.gov (United States)

    Bu, Laju; Hu, Mengxing; Lu, Wanlong; Wang, Ziyu; Lu, Guanghao

    2018-01-01

    Source-semiconductor-drain coplanar transistors with an organic semiconductor layer located within the same plane of source/drain electrodes are attractive for next-generation electronics, because they could be used to reduce material consumption, minimize parasitic leakage current, avoid cross-talk among different devices, and simplify the fabrication process of circuits. Here, a one-step, drop-casting-like printing method to realize a coplanar transistor using a model semiconductor/insulator [poly(3-hexylthiophene) (P3HT)/polystyrene (PS)] blend is developed. By manipulating the solution dewetting dynamics on the metal electrode and SiO 2 dielectric, the solution within the channel region is selectively confined, and thus make the top surface of source/drain electrodes completely free of polymers. Subsequently, during solvent evaporation, vertical phase separation between P3HT and PS leads to a semiconductor-insulator bilayer structure, contributing to an improved transistor performance. Moreover, this coplanar transistor with semiconductor-insulator bilayer structure is an ideal system for injecting charges into the insulator via gate-stress, and the thus-formed PS electret layer acts as a "nonuniform floating gate" to tune the threshold voltage and effective mobility of the transistors. Effective field-effect mobility higher than 1 cm 2 V -1 s -1 with an on/off ratio > 10 7 is realized, and the performances are comparable to those of commercial amorphous silicon transistors. This coplanar transistor simplifies the fabrication process of corresponding circuits. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Buoyancy effects in vertical rectangular duct with coplanar magnetic field and single sided heat load

    Science.gov (United States)

    Kostichev, P. I.; Poddubnyi, I. I.; Razuvanov, N. G.

    2017-11-01

    In some DEMO blanket designs liquid metal flows in vertical ducts of rectangular cross-section between ceramic breeder units providing their cooling. Heat exchange in these conditions is governed by the influence of magnetic field (coplanar) and by buoyancy effects that depend on the flow orientation to the gravity vector (downward and upward flow). Magnetohydrodynamic and heat transfer of liquid metal in vertical rectangular ducts is not well researched. Experimental study of buoyancy effects in rectangular duct with coplanar magnetic field for one-sided heat load and downward and upward flowsis presented in this paper. The detail research with has been done on mercury MHD close loop with using of the probe technique allow to discover several advantageous and disadvantageous effects. The intensive impact of buoyancy force has been observed in a few regime of downward flow which has been laminarized by magnetic field. Due to the development in the flow of the secondary large-scale vortices heat transfer improved and the temperature fluctuations of the abnormally high intensity have been fixed. On the contrary, in the upward flow the buoyancy force stabilized the flow which lead to decreasing of the turbulence heat transfer ratio and, consequently, deterioration of heat transfer.

  3. Numerical and experimental modeling of liquid metal thin film flows in a quasi-coplanar magentic field

    Energy Technology Data Exchange (ETDEWEB)

    Morley, Neil B. [Univ. of California, Los Angeles, CA (United States)

    1994-01-01

    Liquid metal film protection of plasma-facing surfaces in fusion reactors is proposed in an effort to counter the adverse effects of high heat and particle fluxes from the burning plasma. Concerns still exist about establishing the required flow in presence of strong magnetic fields and plasma momentum flux typical of a reactor environment. In this work, the flow behavior of the film is examined under such conditions. Analysis of MHD equations as they apply to liquid metal flows with a free surface in the fully-developed limit was undertaken. Solution yields data for velocity profiles and uniform film heights vs key design parameters (channel size, magnetic field magnitude/orientation, channel slope, wall conductivity). These results are compared to previous models to determine accuracy of simplifying assumptions, in particular Hartmann averaging of films along {rvec B}. Effect of a plasma momentum flux on the thin films is also analyzed. The plasma momentum is strong enough in the cases examined to seriously upset the film, especially for lighter elements like Li. Ga performed much better and its possible use is bolstered by calculations. In an experiment in the MeGA-loop MHD facility, coplanar, wide film flow was found to be little affected by the magnetic field due to the elongated nature of the film. Both MHD drag and partial laminarization are observed, supporting the fully- developed film model predictions of the onset of MHD drag and duct flow estimations for flow laminarization.

  4. Numerical and experimental modeling of liquid metal thin film flows in a quasi-coplanar magentic field

    International Nuclear Information System (INIS)

    Morley, N.B.

    1994-01-01

    Liquid metal film protection of plasma-facing surfaces in fusion reactors is proposed in an effort to counter the adverse effects of high heat and particle fluxes from the burning plasma. Concerns still exist about establishing the required flow in presence of strong magnetic fields and plasma momentum flux typical of a reactor environment. In this work, the flow behavior of the film is examined under such conditions. Analysis of MHD equations as they apply to liquid metal flows with a free surface in the fully-developed limit was undertaken. Solution yields data for velocity profiles and uniform film heights vs key design parameters (channel size, magnetic field magnitude/orientation, channel slope, wall conductivity). These results are compared to previous models to determine accuracy of simplifying assumptions, in particular Hartmann averaging of films along rvec B. Effect of a plasma momentum flux on the thin films is also analyzed. The plasma momentum is strong enough in the cases examined to seriously upset the film, especially for lighter elements like Li. Ga performed much better and its possible use is bolstered by calculations. In an experiment in the MeGA-loop MHD facility, coplanar, wide film flow was found to be little affected by the magnetic field due to the elongated nature of the film. Both MHD drag and partial laminarization are observed, supporting the fully- developed film model predictions of the onset of MHD drag and duct flow estimations for flow laminarization

  5. Analysis of some coplanar transmission lines: coplanar coupled lines, coplanar coupled striplines, and coplanar coupled lines with rectangular microshield

    Science.gov (United States)

    Yuan, Naichang; He, Jianguo; Yao, Demiao; Dai, Qin; Lin, Weigan

    1995-06-01

    Two types of coplanar transmission lines, rectangular microshield coplanar coupled lines (RMCCL) and coplanar coupled rectangular microshield lines (CCRML), are proposed for MMIC applications. These are developed from coplanar coupled lines (CCL) and coplanar coupled strip lines (CCS). Analytic formulas are presented for calculating the quasistatic TEM parameters of these coupled lines by means of exact conformal mapping techniques. Numerical results are also presented to illustrate the properties of these coplanar transmission lines.

  6. Dosimetric comparison between intensity-modulated with coplanar field and 3D conformal radiotherapy with noncoplanar field for postocular invasion tumor.

    Science.gov (United States)

    Wenyong, Tu; Lu, Liu; Jun, Zeng; Weidong, Yin; Yun, Li

    2010-01-01

    This study presents a dosimetric optimization effort aiming to compare noncoplanar field (NCF) on 3 dimensions conformal radiotherapy (3D-CRT) and coplanar field (CF) on intensity-modulated radiotherapy (IMRT) planning for postocular invasion tumor. We performed a planning study on the computed tomography data of 8 consecutive patients with localized postocular invasion tumor. Four fields NCF 3D-CRT in the transverse plane with gantry angles of 0-10 degrees , 30-45 degrees , 240-270 degrees , and 310-335 degrees degrees were isocentered at the center of gravity of the target volume. The geometry of the beams was determined by beam's eye view. The same constraints were prepared with between CF IMRT optimization and NCF 3D-CRT treatment. The maximum point doses (D max) for the different optic pathway structures (OPS) with NCF 3D-CRT treatment should differ in no more than 3% from those with the NCF IMRT plan. Dose-volume histograms (DVHs) were obtained for all targets and organ at risk (OAR) with both treatment techniques. Plans with NCF 3D-CRT and CF IMRT constraints on target dose in homogeneity were computed, as well as the conformity index (CI) and homogeneity index (HI) in the target volume. The PTV coverage was optimal with both NCF 3D-CRT and CF IMRT plans in the 8 tumor sites. No difference was noted between the two techniques for the average D(max) and D(min) dose. NCF 3D-CRT and CF IMRT will yield similar results on CI. However, HI was a significant difference between NCF 3D-CRT and CF IMRT plan (p 3D-CRT versus CF IMRT set-up is very slight. NCF3D-CRT is one of the treatment options for postocular invasion tumor. However, constraints for OARs are needed. 2010 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  7. Dosimetric Comparison Between Intensity-Modulated with Coplanar Field and 3D Conformal Radiotherapy with Noncoplanar Field for Postocular Invasion Tumor

    International Nuclear Information System (INIS)

    Tu Wenyong; Liu Lu; Zeng Jun; Yin Weidong; Li Yun

    2010-01-01

    This study presents a dosimetric optimization effort aiming to compare noncoplanar field (NCF) on 3 dimensions conformal radiotherapy (3D-CRT) and coplanar field (CF) on intensity-modulated radiotherapy (IMRT) planning for postocular invasion tumor. We performed a planning study on the computed tomography data of 8 consecutive patients with localized postocular invasion tumor. Four fields NCF 3D-CRT in the transverse plane with gantry angles of 0-10 deg., 30-45 deg., 240-270 deg., and 310-335 deg. degrees were isocentered at the center of gravity of the target volume. The geometry of the beams was determined by beam's eye view. The same constraints were prepared with between CF IMRT optimization and NCF 3D-CRT treatment. The maximum point doses (D max) for the different optic pathway structures (OPS) with NCF 3D-CRT treatment should differ in no more than 3% from those with the NCF IMRT plan. Dose-volume histograms (DVHs) were obtained for all targets and organ at risk (OAR) with both treatment techniques. Plans with NCF 3D-CRT and CF IMRT constraints on target dose in homogeneity were computed, as well as the conformity index (CI) and homogeneity index (HI) in the target volume. The PTV coverage was optimal with both NCF 3D-CRT and CF IMRT plans in the 8 tumor sites. No difference was noted between the two techniques for the average D max and D min dose. NCF 3D-CRT and CF IMRT will yield similar results on CI. However, HI was a significant difference between NCF 3D-CRT and CF IMRT plan (p < 0.001). Physical endpoints for target showed the mean target dose to be low in the CF IMRT plan, caused by a large target dose in homogeneity (p < 0.001). The impact of NCF 3D-CRT versus CF IMRT set-up is very slight. NCF3D-CRT is one of the treatment options for postocular invasion tumor. However, constraints for OARs are needed.

  8. Reconsidering the advantages of the three-dimensional representation of the interferometric transform for imaging with non-coplanar baselines and wide fields of view

    Science.gov (United States)

    Smith, D. M. P.; Young, A.; Davidson, D. B.

    2017-07-01

    Radio telescopes with baselines that span thousands of kilometres and with fields of view that span tens of degrees have been recently deployed, such as the Low Frequency Array, and are currently being developed, such as the Square Kilometre Array. Additionally, there are proposals for space-based instruments with all-sky imaging capabilities, such as the Orbiting Low Frequency Array. Such telescopes produce observations with three-dimensional visibility distributions and curved image domains. In most work to date, the visibility distribution has been converted to a planar form to compute the brightness map using a two-dimensional Fourier transform. The celestial sphere is faceted in order to counter pixel distortion at wide angles, with each such facet requiring a unique planar form of the visibility distribution. Under the above conditions, the computational and storage complexities of this approach can become excessive. On the other hand, when using the direct Fourier transform approach, which maintains the three-dimensional shapes of the visibility distribution and celestial sphere, the non-coplanar visibility component requires no special attention. Furthermore, as the celestial samples are placed directly on the curved surface of the celestial sphere, pixel distortion at wide angles is avoided. In this paper, a number of examples illustrate that under these conditions (very long baselines and very wide fields of view) the costs of the direct Fourier transform may be comparable to (or even lower than) methods that utilise the two-dimensional fast Fourier transform.

  9. A Numerical Study of Low-Thrust Limited Power Trajectories between Coplanar Circular Orbits in an Inverse-Square Force Field

    Directory of Open Access Journals (Sweden)

    Sandro da Silva Fernandes

    2012-01-01

    Full Text Available A numerical study of optimal low-thrust limited power trajectories for simple transfer (no rendezvous between circular coplanar orbits in an inverse-square force field is performed by two different classes of algorithms in optimization of trajectories. This study is carried out by means of a direct method based on gradient techniques and by an indirect method based on the second variation theory. The direct approach of the trajectory optimization problem combines the main positive characteristics of two well-known direct methods in optimization of trajectories: the steepest-descent (first-order gradient method and a direct second variation (second-order gradient method. On the other hand, the indirect approach of the trajectory optimization problem involves two different algorithms of the well-known neighboring extremals method. Several radius ratios and transfer durations are considered, and the fuel consumption is taken as the performance criterion. For small-amplitude transfers, the results are compared to the ones provided by a linear analytical theory.

  10. Dielectric behaviors of lead zirconate titanate ceramics with coplanar electrodes

    International Nuclear Information System (INIS)

    Wang, Y.; Cheng, Y.L.; Zhang, Y.W.; Chan, H.L.W.; Choy, C.L.

    2003-01-01

    This paper reports on the dielectric behaviors of lead zirconate titanate (PZT) capacitors with coplanar electrodes. Usually a ferroelectric device has a metal-ferroelectric-metal configuration (parallel plate capacitor); when both the electrodes are on one side of a ceramic to form a coplanar capacitor, different dielectric behaviors will be anticipated because of the change in the distribution of the test field inside the dielectrics. This paper describes how the capacitance and dielectric loss of PZT-based coplanar capacitors change with electrode distance, area and test frequency

  11. Treatment planning evaluation of non-coplanar techniques for conformal radiotherapy of the prostate

    International Nuclear Information System (INIS)

    Bedford, James L.; Henrys, Anthony J.; Dearnaley, David P.; Khoo, Vincent S.

    2005-01-01

    Background and purpose: To evaluate the benefit of using non-coplanar treatment plans for irradiation of two different clinical treatment volumes: prostate only (PO) and the prostate plus seminal vesicles (PSV). Material and methods: An inverse planning algorithm was used to produce three-field, four-field, five-field and six-field non-coplanar treatment plans without intensity-modulation in ten patients. These were compared against a three-field coplanar plan. A dose of 74 Gy was prescribed to the isocentre. Plans were compared using the minimum dose to the planning target volume (PTV), maximum dose to the small bowel, and irradiated volumes of rectum, bladder and femoral head. Biological indices were also evaluated. Results: For the PO group, volume of rectum irradiated to 60 Gy (V 60 ) was 22.5±3.7% for the coplanar plan, and 21.5±5.3% for the five-field non-coplanar plan, which was the most beneficial (p=0.3). For the PSV group, the five-field non-coplanar plan was again the most beneficial. Rectal V 60 was in this case reduced from 41.5±10.4% for the coplanar plan to 35.2±9.3% for the non-coplanar plan (p=0.02). Conclusions: The use of non-coplanar beams in conformal prostate radiotherapy provides a small increase in rectal sparing, more significantly with PSV volumes than for PO volumes

  12. Precise magnetostatic field using the finite element method; Calculo de campos magnetostaticos com precisao utilizando o metodo dos elementos finitos

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Francisco Rogerio Teixeira do

    2013-07-01

    The main objective of this work is to simulate electromagnetic fields using the Finite Element Method. Even in the easiest case of electrostatic and magnetostatic numerical simulation some problems appear when the nodal finite element is used. It is difficult to model vector fields with scalar functions mainly in non-homogeneous materials. With the aim to solve these problems two types of techniques are tried: the adaptive remeshing using nodal elements and the edge finite element that ensure the continuity of tangential components. Some numerical analysis of simple electromagnetic problems with homogeneous and non-homogeneous materials are performed using first, the adaptive remeshing based in various error indicators and second, the numerical solution of waveguides using edge finite element. (author)

  13. Nanoscale constrictions in superconducting coplanar waveguide resonators

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, Mark David; Naether, Uta; Ciria, Miguel; Zueco, David; Luis, Fernando, E-mail: fluis@unizar.es [Instituto de Ciencia de Materiales de Aragón, CSIC—Universidad de Zaragoza, 50009 Zaragoza (Spain); Departamento de Física de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza (Spain); Sesé, Javier [Instituto de Nanociencia de Aragón, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Departamento de Física de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza (Spain); Atkinson, James; Barco, Enrique del [Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States); Sánchez-Azqueta, Carlos [Dpto. de Ingeniería Electrónica y Telecomunicaciones, Universidad de Zaragoza, 50009 Zaragoza (Spain); Majer, Johannes [Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, 1020 Vienna (Austria)

    2014-10-20

    We report on the design, fabrication, and characterization of superconducting coplanar waveguide resonators with nanoscopic constrictions. By reducing the size of the center line down to 50 nm, the radio frequency currents are concentrated and the magnetic field in its vicinity is increased. The device characteristics are only slightly modified by the constrictions, with changes in resonance frequency lower than 1% and internal quality factors of the same order of magnitude as the original ones. These devices could enable the achievement of higher couplings to small magnetic samples or even to single molecular spins and have applications in circuit quantum electrodynamics, quantum computing, and electron paramagnetic resonance.

  14. Integral dose investigation of non-coplanar treatment beam geometries in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Dan; Dong, Peng; Ruan, Dan; Low, Daniel A.; Sheng, Ke, E-mail: ksheng@mednet.ucla.edu [Department of Radiation Oncology, University of California, Los Angeles, California 90095 (United States); Long, Troy; Romeijn, Edwin [Department of Industrial and Operations, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2014-01-15

    Purpose: Automated planning and delivery of non-coplanar plans such as 4π radiotherapy involving a large number of fields have been developed to take advantage of the newly available automated couch and gantry on C-arm gantry linacs. However, there is an increasing concern regarding the potential changes in the integral dose that needs to be investigated. Methods: A digital torso phantom and 22 lung and liver stereotactic body radiation therapy (SBRT) patients were included in the study. The digital phantom was constructed as a water equivalent elliptical cylinder with a major axis length of 35.4 cm and minor axis of 23.6 cm. A 4.5 cm diameter target was positioned at varying depths along the major axis. Integral doses from intensity modulated, non-coplanar beams forming a conical pattern were compared against the equally spaced coplanar beam plans. Integral dose dependence on the phantom geometry and the beam number was also quantified. For the patient plans, the non-coplanar and coplanar beams and fluences were optimized using a column generation and pricing approach and compared against clinical VMAT plans using two full (lung) or partial coplanar arcs (liver) entering at the side proximal to the tumor. Both the average dose to the normal tissue volume and the total volumes receiving greater than 2 Gy (V2) and 5 Gy (V5) were evaluated and compared. Results: The ratio of integral dose from the non-coplanar and coplanar plans depended on the tumor depth for the phantom; for tumors shallower than 10 cm, the non-coplanar integral doses were lower than coplanar integral doses for non-coplanar angles less than 60°. Similar patterns were observed in the patient plans. The smallest non-coplanar integral doses were observed for tumor 6–8 cm deep. For the phantom, the integral dose was independent of the number of beams, consistent with the liver SBRT patients but the lung SBRT patients showed slight increase in the integral dose when more beams were used. Larger

  15. SU-F-BRB-04: Comparison of Coplanar VMAT, Non-Coplanar VMAT, and 4π Treatment Plans

    International Nuclear Information System (INIS)

    Woods, K; Nguyen, D; Tran, A; Yu, V; Cao, M; Sheng, K

    2015-01-01

    Purpose: The 4π non-coplanar radiotherapy delivery technique has demonstrated significantly better normal tissue sparing and dose conformality than the clinically used volumetric modulated arc therapy (VMAT). It is unclear whether this is a fundamental limitation of VMAT delivery or the coplanar nature of its typical clinical plans. The non-coplanar basis of 4π is incorporated into VMAT treatment planning to compare its effect on plan quality. Methods: Clinical stereotactic body radiation therapy plans for 9 liver patients treated with 30–60 Gy using coplanar VMAT (cVMAT) were re-planned using non-coplanar VMAT (nVMAT) with 3 arcs and 4 π with 20 intensity-modulated non-coplanar fields. All plans were optimized to deliver 100% of the prescribed dose to 95% of the planning target volume (PTV), and nVMAT and 4π plans were tailored to match the maximum and mean PTV dose from the clinical plan. The conformality index (CI), 50% dose spillage volume (R50), normal liver volume receiving >15 Gy (VL>15), and doses to organs at risk (OARs) were compared for all three treatment plans. Results: Compared to cVMAT, the nVMAT and 4π plans reduced VL>15 by an average of 30.6 cm3 and 96.3 cm3, respectively. The average CI was also reduced from 1.22 (cVMAT) to 1.17 (nVMAT) and 1.14 (4π), indicating higher conformality in the same order. Similarly, R50 was reduced from 3.87 (cVMAT) to 3.58 (nVMAT) and 2.74 (4π). With the exception of the mean right kidney dose, which increased by an average of only 0.6 Gy for nVMAT, the dose differences to OARs were not statistically significant between the two VMAT plans. 4π plans either significantly decreased or maintained OAR doses. Conclusion: While the manual selection of intuitive non-coplanar arcs does show some improvement over coplanar VMAT, the automated beam selection for 4π still results in superior plan quality. This project is supported in part by Varian Medical Systems and NIH R43 CA183390

  16. Coupling ultracold atoms to a superconducting coplanar waveguide resonator

    OpenAIRE

    Hattermann, H.; Bothner, D.; Ley, L. Y.; Ferdinand, B.; Wiedmaier, D.; Sárkány, L.; Kleiner, R.; Koelle, D.; Fortágh, J.

    2017-01-01

    We demonstrate coupling of magnetically trapped ultracold $^87$Rb ground state atoms to a coherently driven superconducting coplanar resonator on an integrated atom chip. We measure the microwave field strength in the cavity through observation of the AC shift of the hyperfine transition frequency when the cavity is driven off-resonance from the atomic transition. The measured shifts are used to reconstruct the field in the resonator, in close agreement with transmission measurements of the c...

  17. Broadband electron spin resonance experiments using superconducting coplanar waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Clauss, Conrad; Bogani, Lapo; Scheffler, Marc; Dressel, Martin [1. Physikalisches Institut, Universitaet Stuttgart (Germany); Bothner, Daniel; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut - Experimentalphysik II and Center for Collective Quantum Phenomena in LISA+, Universitaet Tuebingen (Germany)

    2012-07-01

    In recent years superconducting coplanar devices operating at microwave/GHz frequencies are employed in more and more experimental studies. Here, we present electron spin resonance (ESR) experiments using a superconducting coplanar waveguide to provide the RF field to drive the spin flips. In contrast to conventional ESR studies this allows broadband frequency as well as magnetic field swept observation of the spin resonance. We show experimental data of the spin resonance of the organic radical NitPhoMe (2-(4'-methoxyphenyl)-4,4,5,5-tetra-methylimidazoline-1-oxyl-3-oxide) for frequencies in the range of 1 GHz to 40 GHz and corresponding magnetic fields up to 1.4 T (for g=2). In addition we show the temperature dependence of the ESR signals for temperatures up to 30 K, which is well above the critical temperature of the niobium superconductor.

  18. Dose distribution of non-coplanar irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fukui, Toshiharu; Wada, Yoichi; Takenaka, Eiichi

    1987-02-01

    Non-coplanar irradiations were applied to the treatment of brain tumor. The dose distribution around the target area due to non-coplanar irradiation was half less than the dose when coplanar irradiation used. Integral volume dose due to this irradiation was not always less than that due to conventional opposing or rotational irradiation. This irradiation has the better application to the following;as a boost therapy, glioblastoma multiforme;as a radical therapy, recurrent brain tumor, well differentiated brain tumor such as craniopharyngioma, hypophyseal tumor etc and AV-malformation.

  19. Late morbidity profiles in prostate cancer patients treated to 79-84 Gy by a simple four-field coplanar beam arrangement

    International Nuclear Information System (INIS)

    Chism, Derek B.; Horwitz, Eric M.; Hanlon, Alexandra L.; Pinover, Wayne H.; Mitra, Raj K.; Hanks, Gerald E.

    2003-01-01

    Purpose: To describe the frequency and magnitude of late GI and GU morbidity in prostate cancer patients treated to high dose levels with a simple three-dimensional conformal technique. Methods and Materials: A total of 156 intermediate- and high-risk patients were treated between January 1, 1992 and February 28, 1999 with a simple four-field three-dimensional conformal technique to 79-84 Gy. All patients were treated with a four-field conformal technique; the prostate received 82 Gy and the seminal vesicles and periprostatic tissue 46 Gy. GI and GU toxicity was scored according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Morbidity Grading Scale and compared using Kaplan-Meier estimates. Results: The late Grade 2 GI complication rate was 9% and 38% at 3 years for patients treated with and without rectal blocking, respectively (p=0.0004). No Grade 3 late GI complications developed. The rate of Grade 2 late GU complications was 5%, 8%, and 12% at 12, 24, and 36 months, respectively. The Grade 3 late GU complication rate was 2% at 36 months. These differences were not statistically significant. Conclusion: The treatment method described is a simple four-field conformal technique that can be easily implemented in the general radiation community. A dose of 79-84 Gy can be safely delivered to the prostate, with a 9% rate of late Grade 2 GI, 12% rate of late Grade 2 GU, and 2% rate of late Grade 3 GU complications

  20. Experimental investigations on channelized coplanar waveguide

    Science.gov (United States)

    Simons, Rainee N.; Ponchak, George E.; Martzaklis, Konstantinas S.; Romanofsky, Robert R.

    1990-01-01

    A new variant of coplanar waveguide (CPW) which was termed channelized coplanar waveguide (CCPW) is presented. Measured propagation characteristics for CCPW such as epsilon(eff) and unloaded Q as a function of geometrical parameters and frequency are presented. The measured and modeled epsilon(eff) are also compared. Equivalent circuit model element values are presented for a CCPW open circuit and a CCPW right angle bend. A CCPW matched T-junction, matched 1:3 junction, and a novel coax-to-CCPW in-phase, N-way, radial power divider are also demonstrated.

  1. Field theory methods applied for the study of superconductivity in one-dimensional systems; Metodos de teoria de campos no estudo da supercondutividade em sistemas unidimensionais

    Energy Technology Data Exchange (ETDEWEB)

    Martins, M J

    1987-12-31

    It is shown that the Froehlich`s hamiltonian in one spatial dimension is identical to that of an exactly solvable field Theory. The spectrum of the theory is computed. A critical coupling is found above which the system becomes unstable, indicating a superconducting transition. It is also proposed and investigated a renormalizable relativistic field theory model in two space-time dimensions, with quartic self-interaction among N species of fermions, which undergoes dynamical generation of a superconducting gap and is asymptotically free. A finite temperature is introduced and, for N -> {infinity} a critical value T{sub c} is found above which the gap vanishes. (author).

  2. Computer simulating for oil fields with artificial elevation method by electrical submersible pump; Simulacao computacional para pocos de petroleo com metodo de elevacao artificial por bombeio centrifugo submerso

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Evellyne da Silva; Maitelli, Andre Laurindo [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Costa, Rutacio de Oliveira [PETROBRAS S.A., Natal, RN (Brazil). Unidade de Negocio RN/CE; Barbosa, Tiago de Souza [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia de Computacao

    2008-07-01

    The architecture heterogeneities and petrophysical properties of carbonate reservoirs result from a combination of platform morphology, related depositional environments, relative sea level changes and diagenetic events. The reservoir layering built for static and dynamic modelling purposes should reflect the key heterogeneities (depositional or diagenetic) which govern the fluid flow patterns. The layering needs to be adapted to the goal of the modelling, ranging from full field computations of hydrocarbon volumes, to sector-based fine-scale simulations to test the recovery improvement. This paper illustrates various reservoir layering types, including schemes dominated by depositional architecture, and those more driven by the diagenetic overprint. The examples include carbonate platform reservoirs from different stratigraphic settings (Tertiary, Cretaceous, Jurassic and Permian) and different regions (Europe, Africa and Middle East areas). This review shows how significant stratigraphic surfaces (such as sequence boundaries or maximum flooding) with their associated facies shifts, can be often considered as key markers to constrain the reservoir layering. Conversely, how diagenesis (dolomitization and karst development), resulting in units with particular poroperm characteristics, may significantly overprint the primary reservoir architecture by generating flow units which cross-cut depositional sequences. To demonstrate how diagenetic processes can create reservoir bodies with geometries that cross-cut the depositional fabric, different types of dolomitization and karst development are illustrated. (author)

  3. Magnetic hysteresis effects in superconducting coplanar microwave resonators

    Energy Technology Data Exchange (ETDEWEB)

    Bothner, D.; Gaber, T.; Kemmler, M.; Gruenzweig, M.; Ferdinand, B.; Koelle, D.; Kleiner, R. [Universitaet Tuebingen (Germany); Wuensch, S.; Siegel, M. [Karlsruher Institut fuer Technologie (Germany); Mikheenko, P.; Johansen, T.H. [University of Oslo (Norway)

    2013-07-01

    We present experimental data regarding the impact of external magnetic fields on quality factor and resonance frequency of superconducting microwave resonators in a coplanar waveguide geometry. In particular we focus on the influence of magnetic history and show with the assistance of numerical calculations that the found hysteretic behaviour can be well understood with a highly inhomogeneous microwave current density in combination with established field penetration models for type-II superconducting thin films. Furthermore we have used magneto-optical imaging techniques to check the field distribution which we have assumed in our calculations. Finally, we demonstrate that and how the observed hysteretic behaviour can be used to optimize and tune the resonator performance for possible hybrid quantum sytems in magnetic fields.

  4. Coplanar stripline components for high frequency application

    Science.gov (United States)

    Goverdhanam, Kavita; Simons, Rainee N.; Dib, Nihad; Katehi, Linda P. B.

    1996-01-01

    In this paper, coplanar stripline discontinuities such as a slit, a right angle bend and a T-junction are characterized and their performance is parameterized with respect to frequency and geometry. Lumped equivalent circuits are presented for some of them. The element values are obtained from the measured discontinuity scattering (S) parameters. The experimental results are compared with theoretical data obtained using the Finite Difference Time Domain (FD-TD) technique for validation and show very good agreement.

  5. Lung stereotactic body radiotherapy using a coplanar versus a non-coplanar beam technique: a comparison of clinical outcomes

    Science.gov (United States)

    Stauder, Michael C.; Miller, Robert C.; Garces, Yolanda I.; Foote, Robert L.; Sarkaria, Jann N.; Bauer, Heather J.; Mayo, Charles S.; Olivier, Kenneth R.

    2013-01-01

    Objectives To determine if lung stereotactic body radiotherapy (SBRT) using a coplanar beam technique was associated with similar outcomes as lung SBRT using a non-coplanar beam technique. Methods A retrospective review was performed of patients undergoing lung SBRT between January 2008 and April 2011. SBRT was initially delivered with multiple non-coplanar, non-overlapping beams; however, starting in December 2009, SBRT was delivered predominantly with all coplanar beams in order to reduce treatment time and complexity. Results This analysis included 149 patients; the median follow-up was 21 months. SBRT was delivered for primary (n = 90) or recurrent (n = 17) non-small cell lung cancer, or lung oligometastasis (n = 42). The most common dose (Gy)/fraction (fx) regimens were 48 Gy/4 fx (39%), 54 Gy/3 fx (37%), and 50 Gy/5 fx (17%). The beam arrangement was coplanar in 61 patients (41%) and non-coplanar in 88 patients (59%). In patients treated with 54 Gy/3 fx, the mean treatment times per fraction for the coplanar and non-coplanar cohorts were 10 and 14 minutes (p < 0.0001). Kaplan-Meier 2-year estimates of overall survival (OS), progression-free survival, and local control (LC) for the coplanar and non-coplanar cohorts were 65% vs. 56% (p = 0.30), 47% vs. 39% (p = 0.71), and 92% and 92% (p = 0.94), respectively. The 1-year estimates of grade 2-5 pulmonary toxicity for the coplanar and non-coplanar cohorts were 11% and 17%, respectively (p = 0.30). On multivariate analysis, beam arrangement was not significantly associated with OS, LC or pulmonary toxicity. Conclusions Patients treated with lung SBRT using a coplanar technique had similar outcomes as those treated with a non-coplanar technique. PMID:29296365

  6. 3D printed biomimetic whisker-based sensor with co-planar capacitive sensing

    NARCIS (Netherlands)

    Delamare, John; Sanders, Remco G.P.; Krijnen, Gijsbertus J.M.

    2016-01-01

    This paper describes the development of a whisker sensor for tactile purposes and which is fabricated by 3D printing. Read-out consists of a capacitive measurement of a co-planar capacitance which is affected by a dielectric that is driven into the electric field of the capacitance. The current

  7. The Clinical Value of Non-Coplanar Photon Beams in Biologically Optimized Intensity Modulated Dose Delivery on Deep-Seated Tumours

    International Nuclear Information System (INIS)

    Ferreira, Brigida C.; Svensson, Roger; Loef, Johan; Brahme, Anders

    2003-01-01

    The aim of the present study is to compare the merits of different radiobiologically optimized treatment techniques using few-field planar and non-coplanar dose delivery on an advanced cancer of the cervix, with rectum and bladder as principal organs at risk. Classically, the rational for using non-coplanar beams is to minimize the overlap of beam entrance and exit regions and to find new beam directions avoiding organs at risk, in order to reduce damage to sensitive normal tissues. Two four-beam configurations have been extensively studied. The first consists of three evenly spaced coplanar beams and a fourth non-coplanar beam. A second tetrahedral-like configuration, with two symmetric non-coplanar beams at the same gantry angle and two coplanar beams, with optimized beam directions, was also tested. The present study shows that when radiobiologically optimized intensity modulated beams are applied to such a geometry, only a marginal increase in the treatment outcome can be achieved by non-coplanar beams compared to the optimal coplanar treatment. The main reason for this result is that the high dose in the beam-overlap regions is already optimally reduced by biologically optimized intensity modulation in the plane. The large number of degrees of freedom already incorporated in the treatment by the use of intensity modulation and radiobiological optimization, leads to the saturation of the benefit acquired by a further increase in the degrees of freedom with non-coplanar beams. In conclusion, the use coplanar of radiobiologically optimized intensity modulation simplifies the dose delivery, reducing the need for non-coplanar beam portals

  8. Dynamics of dielectric barrier discharges in coplanar arrangements

    International Nuclear Information System (INIS)

    Gibalov, Valentin I; Pietsch, Gerhard J

    2004-01-01

    The development of a discharge channel in coplanar dielectric barrier arrangements is investigated numerically. Its behaviour in oxygen, like the spatial and temporal distributions of the field strength, charged and neutral particles and energy density, is described in detail. It is found that the streamer development is mainly determined by photoemission. A cathode layer appears near the position where the cathode directed streamer touches the dielectric surface. Secondary electron emission by ion collisions becomes significant and the parameters of the cathode layer are near those of a normal glow discharge. The charge transfer and energy release happen in the conductive channel of the discharge, which appears on the dielectric surface as a result of the cathode streamer development. The field strength in the conductive channel is nearly constant and about 70-100 Td in oxygen and air

  9. Optimized coplanar waveguide resonators for a superconductor–atom interface

    Energy Technology Data Exchange (ETDEWEB)

    Beck, M. A., E-mail: mabeck2@wisc.edu; Isaacs, J. A.; Booth, D.; Pritchard, J. D.; Saffman, M.; McDermott, R. [Department of Physics, University Of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706 (United States)

    2016-08-29

    We describe the design and characterization of superconducting coplanar waveguide cavities tailored to facilitate strong coupling between superconducting quantum circuits and single trapped Rydberg atoms. For initial superconductor–atom experiments at 4.2 K, we show that resonator quality factors above 10{sup 4} can be readily achieved. Furthermore, we demonstrate that the incorporation of thick-film copper electrodes at a voltage antinode of the resonator provides a route to enhance the zero-point electric fields of the resonator in a trapping region that is 40 μm above the chip surface, thereby minimizing chip heating from scattered trap light. The combination of high resonator quality factor and strong electric dipole coupling between the resonator and the atom should make it possible to achieve the strong coupling limit of cavity quantum electrodynamics with this system.

  10. MXene-on-Paper Coplanar Microsupercapacitors

    KAUST Repository

    Kurra, Narendra

    2016-09-05

    A simple and scalable direct laser machining process to fabricate MXene-on-paper coplanar microsupercapacitors is reported. Commercially available printing paper is employed as a platform in order to coat either hydrofluoric acid-etched or clay-like 2D Ti3C2 MXene sheets, followed by laser machining to fabricate thick-film MXene coplanar electrodes over a large area. The size, morphology, and conductivity of the 2D MXene sheets are found to strongly affect the electrochemical performance due to the efficiency of the ion-electron kinetics within the layered MXene sheets. The areal performance metrics of Ti3C2 MXene-on-paper microsupercapacitors show very competitive power-energy densities, comparable to the reported state-of-the-art paper-based microsupercapacitors. Various device architectures are fabricated using the MXene-on-paper electrodes and successfully demonstrated as a micropower source for light emitting diodes. The MXene-on-paper electrodes show promise for flexible on-paper energy storage devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. The treatment of extensive scalp lesions using coplanar and non-coplanar photon IMRT: a single institution experience

    International Nuclear Information System (INIS)

    Ostheimer, Christian; Janich, Martin; Hübsch, Patrick; Gerlach, Reinhard; Vordermark, Dirk

    2014-01-01

    This clinical study compared four different cases of extensive scalp malignancies treated by intensity-modulated radiation therapy. The merits of coplanar and non-coplanar Step-and-shoot total scalp irradiation techniques were evaluated against the background of the literature. Four patients (angiosarcoma, n=2, cutaneous B-cell non-Hodgkin lymphoma, B-NHL, n=1, mycosis fungoides, n=1) treated between 2008 and 2012 at our institution were retrospectively analyzed. For every patient with executed coplanar plan, a non-coplanar plan and vice versa has been calculated additionally for direct comparison. Three patients underwent limited surgery before radiotherapy. Individual adapted bolus material was used for every patient (helmet). Total scalp dose was 30 Gy (B-NHL, mycosis fungoides) and 50 Gy (angiosarcoma) with fractional doses of 2.0-2.5 Gy (without sequential local boost in three patients). Conformity and homogeneity indexes and dose volume histograms were used for treatment plan comparison. Dose hot spots were higher in coplanar plans (110-128% Dmax). Non-coplanar plans showed a more homogeneous dose distribution (HI = .12 - .17) and superior PTV coverage (88 - 96%). Target dose coverage was 81-117% in non-coplanar and 30-128% in coplanar plans. Coplanar plans yielded a stronger dose gradient across the target (.7-1.6 Gy/mm) compared to non-coplanar plans (.8-1.3 Gy/mm). The most conformal plan was a non-coplanar plan (CI = .7). Mean and maximum brain doses were comparable and showed an almost linear decrease between min. and max. dose. The optic chiasm and brain stem was spared most with non-coplanar plans, mean doses to the lenses ranged between 4 and 8 Gy and were higher in non-coplanar plans as were doses to the optic nerves. Radiotherapy tolerance was acceptable and acute side effects included erythema, scalp pain, alopecia and radiodermatitis which all spontaneously resolved. Two patients accomplished partial response, two patients showed complete response

  12. Coplanar strips for Josephson voltage standard circuits

    International Nuclear Information System (INIS)

    Schubert, M.; May, T.; Wende, G.; Fritzsch, L.; Meyer, H.-G.

    2001-01-01

    We present a microwave circuit for Josephson voltage standards. Here, the Josephson junctions are integrated in a microwave transmission line designed as coplanar strips (CPS). The new layout offers the possibility of achieving a higher scale of integration and to considerably simplify the fabrication technology. The characteristic impedance of the CPS is about 50 Ω, and this should be of interest for programmable Josephson voltage standard circuits with SNS or SINIS junctions. To demonstrate the function of the microwave circuit design, conventional 10 V Josephson voltage standard circuits with 17000 Nb/AlO x /Nb junctions were prepared and tested. Stable Shapiro steps at the 10 V level were generated. Furthermore, arrays of 1400 SINIS junctions in this microwave layout exhibited first-order Shapiro steps. Copyright 2001 American Institute of Physics

  13. Image Reconstruction in Radio Astronomy with Non-Coplanar Synthesis Arrays

    Science.gov (United States)

    Goodrick, L.

    2015-03-01

    Traditional radio astronomy imaging techniques assume that the interferometric array is coplanar, with a small field of view, and that the two-dimensional Fourier relationship between brightness and visibility remains valid, allowing the Fast Fourier Transform to be used. In practice, to acquire more accurate data, the non-coplanar baseline effects need to be incorporated, as small height variations in the array plane introduces the w spatial frequency component. This component adds an additional phase shift to the incoming signals. There are two approaches to account for the non-coplanar baseline effects: either the full three-dimensional brightness and visibility model can be used to reconstruct an image, or the non-coplanar effects can be removed, reducing the three dimensional relationship to that of the two-dimensional one. This thesis describes and implements the w-projection and w-stacking algorithms. The aim of these algorithms is to account for the phase error introduced by non-coplanar synthesis arrays configurations, making the recovered visibilities more true to the actual brightness distribution model. This is done by reducing the 3D visibilities to a 2D visibility model. The algorithms also have the added benefit of wide-field imaging, although w-stacking supports a wider field of view at the cost of more FFT bin support. For w-projection, the w-term is accounted for in the visibility domain by convolving it out of the problem with a convolution kernel, allowing the use of the two-dimensional Fast Fourier Transform. Similarly, the w-Stacking algorithm applies a phase correction in the image domain to image layers to produce an intensity model that accounts for the non-coplanar baseline effects. This project considers the KAT7 array for simulation and analysis of the limitations and advantages of both the algorithms. Additionally, a variant of the Högbom CLEAN algorithm was used which employs contour trimming for extended source emission flagging. The

  14. Low loss superconducting titanium nitride coplanar waveguide resonators

    International Nuclear Information System (INIS)

    Vissers, M. R.; Gao, J.; Wisbey, D. S.; Hite, D. A.; Pappas, D. P.; Tsuei, C. C.; Corcoles, A. D.; Steffen, M.

    2010-01-01

    Thin films of TiN were sputter-deposited onto Si and sapphire wafers with and without SiN buffer layers. The films were fabricated into rf coplanar waveguide resonators, and internal quality factor measurements were taken at millikelvin temperatures in both the many photon and single photon limits, i.e., high and low electric field regimes, respectively. At high field, we found the highest internal quality factors (∼10 7 ) were measured for TiN with predominantly a (200)-TiN orientation. The (200)-TiN is favored for growth at high temperature on either bare Si or SiN buffer layers. However, growth on bare sapphire or Si(100) at low temperature resulted in primarily a (111)-TiN orientation. Ellipsometry and Auger measurements indicate that the (200)-TiN growth on the bare Si substrates is correlated with the formation of a thin, ≅2 nm, layer of SiN during the predeposition procedure. On these surfaces we found a significant increase of Q i for both high and low electric field regimes.

  15. Coplanar transitions based on aluminum nitride interposer substrate for terabit transceivers

    DEFF Research Database (Denmark)

    Dong, Yunfeng; Johansen, Tom Keinicke; Zhurbenko, Vitaliy

    2017-01-01

    This paper presents two types of coplanar transitions based on aluminum nitride (AlN) substrate for interposer designs of terabit transceivers. The designs of coupled coplanar waveguide (CCPW), coupled line, coplanar waveguide (CPW), and coplanar stripline (CPS) based on AlN substrate are explained...

  16. SU-F-T-416: Dosimetric Comparison of Coplanar and Non-Coplanar IMRT Plans for Peripheral Lung Lesion

    International Nuclear Information System (INIS)

    Kang, J; Zhang, S; Philbrook, S; Paul, S; Wang, B

    2016-01-01

    Purpose: The purpose of this study was to compare dosimetric parameters of treatment plans between coplanar and non-coplanar techniques for treating peripheral lung lesions. Methods: The planning CT scans of 6 patients in supine positions were used in this study. The size of the PTV ranges from 163 c.c. to 782 c.c.. The locations of PTV are mostly at the peripheral of Lung, some spreading to the mediastinum. For each patient, we generated two IMRT plans, one with and the other without non-coplanar beams. The non-coplanar beams were carefully selected so that the beams would never exit patient bodies through the contralateral lung. The IMRT plans were generated with Pinnacle 9.8 treatment planning software. The IMRT optimization objectives were kept the same for the corresponding pairs of plans. All plans were normalized such that 95% of PTV receives the prescription dose (full dose). Results: The conformity index (mean±standard deviation of the mean) is 1.49±0.14 and 1.58±0.23 for the coplanar and noncoplanar plans, respectively. The heterogeneity index (mean±standard deviation of the mean) is 7.74 ±2.33 and 6.34±1.40 for the coplanar and non-coplanar plans, respectively. The maximum heart dose is 60.94±6.22 and 60.42±7.21 Gy, and mean heart dose is 10.22 ±7.57, 9.07 ±6.32 Gy, for the coplanar and non-coplanar plans, respectively. The ipsilateral lung V20 is 48.0%±2.4% and 47.5%±3.3%, and V5 is 68.2%±10.0% and 69.1%±7.3%, for the coplanar and noncoplanar plans, respectively. Furthermore, with the non-coplanar beam arrangement, the contralateral lung V20 was reduced from 3.3%±3.7% to 1.3%±0.8%, and the contralateral Lung V5 is reduced significantly from 65.6%±9.3% to 33.5%±20.9% (p value =0.008). Conclusion: The IMRT plans with non-coplanar beam arrangement could reduce the exit dose to the contralateral lung, and therefore reduce the contralateral lung V5 significantly. This method is especially helpful while the lung lesion doesn’t have a

  17. Optimal Non-Coplanar Launch to Quick Rendezvous

    National Research Council Canada - National Science Library

    Sears, Gregory

    1997-01-01

    The purpose of this study was to determine the feasibility of launching a Delta Clipper-like vehicle on an optimal, non-coplanar trajectory to rendezvous with an earth orbiting object in one orbit or less...

  18. SU-D-BRB-01: A Comparison of Learning Methods for Knowledge Based Dose Prediction for Coplanar and Non-Coplanar Liver Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tran, A; Ruan, D; Woods, K; Yu, V; Nguyen, D; Sheng, K [UCLA School of Medicine, Los Angeles, CA (United States)

    2016-06-15

    Purpose: The predictive power of knowledge based planning (KBP) has considerable potential in the development of automated treatment planning. Here, we examine the predictive capabilities and accuracy of previously reported KBP methods, as well as an artificial neural networks (ANN) method. Furthermore, we compare the predictive accuracy of these methods on coplanar volumetric-modulated arc therapy (VMAT) and non-coplanar 4π radiotherapy. Methods: 30 liver SBRT patients previously treated using coplanar VMAT were selected for this study. The patients were re-planned using 4π radiotherapy, which involves 20 optimally selected non-coplanar IMRT fields. ANNs were used to incorporate enhanced geometric information including liver and PTV size, prescription dose, patient girth, and proximity to beams. The performance of ANN was compared to three methods from statistical voxel dose learning (SVDL), wherein the doses of voxels sharing the same distance to the PTV are approximated by either taking the median of the distribution, non-parametric fitting, or skew-normal fitting. These three methods were shown to be capable of predicting DVH, but only median approximation can predict 3D dose. Prediction methods were tested using leave-one-out cross-validation tests and evaluated using residual sum of squares (RSS) for DVH and 3D dose predictions. Results: DVH prediction using non-parametric fitting had the lowest average RSS with 0.1176(4π) and 0.1633(VMAT), compared to 0.4879(4π) and 1.8744(VMAT) RSS for ANN. 3D dose prediction with median approximation had lower RSS with 12.02(4π) and 29.22(VMAT), compared to 27.95(4π) and 130.9(VMAT) for ANN. Conclusion: Paradoxically, although the ANNs included geometric features in addition to the distances to the PTV, it did not perform better in predicting DVH or 3D dose compared to simpler, faster methods based on the distances alone. The study further confirms that the prediction of 4π non-coplanar plans were more accurate than

  19. LHC data and cosmic ray coplanarity at superhigh energies

    Directory of Open Access Journals (Sweden)

    Mukhamedshin R.A.

    2017-01-01

    Full Text Available A new phenomenological model FANSY 2.0 is designed, which makes it possible to simulate hadron interactions via traditional and coplanar generation of most energetic particles as well as to reproduce a lot of LHC (ALICE, ATLAS, CMS, TOTEM, LHCf data. Features of the model are compared with LHC data. Problems of coplanarity are considered and a testing experiment is proposed.

  20. Ultra-Wideband Coplanar-Fed Monopoles: A Comparative Study

    Directory of Open Access Journals (Sweden)

    J. Jilkova

    2008-04-01

    Full Text Available The paper provides an experimental comparison of four types of ultra-wideband coplanar-fed planar monopole antennas. Parameters of the open stub completed by an L-shaped monopole and the cross monopole were adopted from the literature. The forked monopole and the coplanar monopole were fabricated and measured. Monopoles were compared from the viewpoint of the impedance bandwidth, gain, directivity patterns and dimensions.

  1. An Experimental and Numerical Study on Cracking Behavior of Brittle Sandstone Containing Two Non-coplanar Fissures Under Uniaxial Compression

    Science.gov (United States)

    Yang, Sheng-Qi; Tian, Wen-Ling; Huang, Yan-Hua; Ranjith, P. G.; Ju, Yang

    2016-04-01

    To understand the fracture mechanism in all kinds of rock engineering, it is important to investigate the fracture evolution behavior of pre-fissured rock. In this research, we conducted uniaxial compression experiments to evaluate the influence of ligament angle on the strength, deformability, and fracture coalescence behavior of rectangular prismatic specimens (80 × 160 × 30 mm) of brittle sandstone containing two non-coplanar fissures. The experimental results show that the peak strength of sandstone containing two non-coplanar fissures depends on the ligament angle, but the elastic modulus is not closely related to the ligament angle. With the increase of ligament angle, the peak strength decreased at a ligament angle of 60°, before increasing up to our maximum ligament angle of 120°. Crack initiation, propagation, and coalescence were all observed and characterized from the inner and outer tips of pre-existing non-coplanar fissures using photographic monitoring. Based on the results, the sequence of crack evolution in sandstone containing two non-coplanar fissures was analyzed in detail. In order to fully understand the crack evolution mechanism of brittle sandstone, numerical simulations using PFC2D were performed for specimens containing two non-coplanar fissures under uniaxial compression. The results are in good agreement with the experimental results. By analyzing the stress field, the crack evolution mechanism in brittle sandstone containing two non-coplanar fissures under uniaxial compression is revealed. These experimental and numerical results are expected to improve the understanding of the unstable fracture mechanism of fissured rock engineering structures.

  2. Quality factor of a transmission line coupled coplanar waveguide resonator

    Energy Technology Data Exchange (ETDEWEB)

    Besedin, Ilya [National University for Science and Technology (MISiS), Moscow (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation); Menushenkov, Alexey P. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation)

    2018-12-15

    We investigate analytically the coupling of a coplanar waveguide resonator to a coplanar waveguide feedline. Using a conformal mapping technique we obtain an expression for the characteristic mode impedances and coupling coefficients of an asymmetric multi-conductor transmission line. Leading order terms for the external quality factor and frequency shift are calculated. The obtained analytical results are relevant for designing circuit-QED quantum systems and frequency division multiplexing of superconducting bolometers, detectors and similar microwave-range multi-pixel devices. (orig.)

  3. Coplanar Electrode Layout Optimized for Increased Sensitivity for Electrical Impedance Spectroscopy

    DEFF Research Database (Denmark)

    Clausen, Casper Hyttel; Skands, Gustav Erik; Bertelsen, Christian Vinther

    2015-01-01

    This work describes an improvement in the layout of coplanar electrodes for electrical impedance spectroscopy. We have developed, fabricated, and tested an improved electrode layout, which improves the sensitivity of an impedance flow cytometry chip. The improved chip was experimentally tested...... and compared to a chip with a conventional electrode layout. The improved chip was able to discriminate 0.5 mu m beads from 1 mu m as opposed to the conventional chip. Furthermore, finite element modeling was used to simulate the improvements in electrical field density and uniformity between the electrodes...... of the new electrode layout. Good agreement was observed between the model and the obtained experimental results....

  4. Scienza e conoscenza: sul valore del metodo scientifico

    Directory of Open Access Journals (Sweden)

    Riccardo Luciano Appolloni

    2014-05-01

    Full Text Available L’antico problema di riconoscere una forma di conoscenza oggettivae fondata è ancora vivo; in questo scritto cercheremo di capire se la scienza moderna possa essere una forma di conoscenza tale e, quindi, privilegiata. A tal fine ci serviremo del pensiero di alcuni epistemologi e scienziati. In particolare, nel trattare il problema del valore epistemologico del metodo scientifico, non potremo esimerci dal fare i conti con l’anarchismo metodologico di Paul K. Feyerabend, verso il quale l’esito del presente articolo sarà fondamentalmente critico. A partire dai fecondi spunti di questo filosofo, tenteremo dapprima di analizzare i caratteri distintivi della scienza e del suo metodo rispetto ad altre forme di sapere; quindi, cercheremo di individuare alcuni limiti della conoscenza razionale.

  5. A secondary, coplanar design Ni/MCM-41/Zn microbattery

    Science.gov (United States)

    Meskon, S. R.; Othman, R.; Ani, M. H.

    2018-01-01

    A secondary Ni/Zn microbattery (∼200 µm thick) has been developed in a coplanar electrode configuration. The cell is essentially of a circular shape (∼30 mm in diameter) consisting of a fine circular ring (cathode) and a circle (anode) split apart (~800 µm). Unlike the stacking cell architecture, coplanar configuration offers simple design, ease of fabrication and eventually cost saving. The use of MCM-41 mesoporous silica as the membrane separator cum electrolyte reservoir enables the successful implementation of coplanar configuration. The fabrication of Ni/Zn microbattery first begins with electrodeposition of zinc (Zn) and nickel hydroxide (Ni(OH)2) thin films onto patterned FR4 printed circuit board, followed by deposition of zinc oxide (ZnO) slurry onto the zinc active layer, and finally ends by multiple drop-coating procedures of MCM-41 from its precursor solution at ambient temperature. Once a potassium hydroxide (6 M KOH)/MCM-41 electrolyte-separator mixture is incorporated, the cell is sealed with an acrylic sheet and epoxy adhesive. The fabricated microbatteries were capable to sustain around 130 deep charge-discharge cycles. When rated at 0.1 mA, the energy density of the microbattery was around 3.82 Wh l-1 which is suitable for low rate applications and storage for micro energy harvesters such as piezoelectric generators.

  6. Jaws calibration method to get a homogeneous distribution of dose in the junction of hemi fields; Metodo de calibracion de mandibulas para conseguir una distribucion homogenea de dosis en la zona de union de hemicampos

    Energy Technology Data Exchange (ETDEWEB)

    Cenizo de Castro, E.; Garcia Pareja, S.; Moreno Saiz, C.; Hernandez Rodriguez, R.; Bodineau Gil, C.; Martin-Viera Cueto, J. A.

    2011-07-01

    Hemi fields treatments are widely used in radiotherapy. Because the tolerance established for the positioning of each jaw is 1 mm, may be cases of overlap or separation of up to 2 mm. This implies heterogeneity of doses up to 40% in the joint area. This paper presents an accurate method of calibration of the jaws so as to obtain homogeneous dose distributions when using this type of treatment. (Author)

  7. Control of polymer-packing orientation in thin films through synthetic tailoring of backbone coplanarity

    KAUST Repository

    Chen, Mark S.

    2013-10-22

    Controlling solid-state order of π-conjugated polymers through macromolecular design is essential for achieving high electronic device performance; yet, it remains a challenge, especially with respect to polymer-packing orientation. Our work investigates the influence of backbone coplanarity on a polymer\\'s preference to pack face-on or edge-on relative to the substrate. Isoindigo-based polymers were synthesized with increasing planarity by systematically substituting thiophenes for phenyl rings in the acceptor comonomer. This increasing backbone coplanarity, supported by density functional theory (DFT) calculations of representative trimers, leads to the narrowing of polymer band gaps as characterized by ultraviolet-visible-near infrared (UV-vis-NIR) spectroscopy and cyclic voltammetry. Among the polymers studied, regiosymmetric II and TII polymers exhibited the highest hole mobilities in organic field-effect transistors (OFETs), while in organic photovoltaics (OPVs), TBII polymers that display intermediate levels of planarity provided the highest power conversion efficiencies. Upon thin-film analysis by atomic force microscropy (AFM) and grazing-incidence X-ray diffraction (GIXD), we discovered that polymer-packing orientation could be controlled by tuning polymer planarity and solubility. Highly soluble, planar polymers favor face-on orientation in thin films while the less soluble, nonplanar polymers favor an edge-on orientation. This study advances our fundamental understanding of how polymer structure influences nanostructural order and reveals a new synthetic strategy for the design of semiconducting materials with rationally engineered solid-state properties. © 2013 American Chemical Society.

  8. Optimization of the coplanar interdigital capacitive sensor

    Science.gov (United States)

    Huang, Yunzhi; Zhan, Zheng; Bowler, Nicola

    2017-02-01

    Interdigital capacitive sensors are applied in nondestructive testing and material property characterization of low-conductivity materials. The sensor performance is typically described based on the penetration depth of the electric field into the sample material, the sensor signal strength and its sensitivity. These factors all depend on the geometry and material properties of the sensor and sample. In this paper, a detailed analysis is provided, through finite element simulations, of the ways in which the sensor's geometrical parameters affect its performance. The geometrical parameters include the number of digits forming the interdigital electrodes and the ratio of digit width to their separation. In addition, the influence of the presence or absence of a metal backplane on the sample is analyzed. Further, the effects of sensor substrate thickness and material on signal strength are studied. The results of the analysis show that it is necessary to take into account a trade-off between the desired sensitivity and penetration depth when designing the sensor. Parametric equations are presented to assist the sensor designer or nondestructive evaluation specialist in optimizing the design of a capacitive sensor.

  9. Influence of infrared stimulation on spectroscopy characteristics of co-planar grid CdZnTe detectors

    International Nuclear Information System (INIS)

    Fjodorov, V.; Ivanov, V.; Loutchanski, A.

    2015-01-01

    It was previously found that illumination with monochromatic infrared (IR) light with wavelengths close to the absorption edge of the CdZnTe exert significant positive influence on the spectrometric characteristics of quasi-hemispherical CdZnTe detectors at room temperature. In this paper, preliminary results of IR stimulation on the spectrometric characteristics of coplanar-grid CdZnTe detectors as well as results of further studies of planar and quasi-hemispherical detectors are presented. Coplanar-grid detectors of 10 mm x 10 mm x 10 mm from Redlen Technologies and commercial available IR LEDs with different wavelengths of 800-1000 nm were used in the experiments. Influence of intensity and direction of IR illumination on the detector's characteristics was studied. Analysis of signals shapes from the preamplifiers outputs at registration of alpha particles showed that IR illumination leads to a change in the shapes of these signals. This may indicate changes in electric fields distributions. An improvement in energy resolution at gamma-energy of 662 keV was observed with quasi-hemispherical and co-planar detectors at the certain levels of IR illumination intensity. The most noticeable effect of IR stimulation was observed with quasi-hemispherical detectors. It is due with optimization of charge collection conditions in the quasi-hemispherical detectors under IT stimulation. (authors)

  10. Ultra-Wideband Notched Characteristic Fed by Coplanar Waveguide

    Directory of Open Access Journals (Sweden)

    Rastanto Hadinegoro

    2015-02-01

    Full Text Available In this paper, a novel Ultra-Wide Band (UWB notch patch antenna with co-planar waveguide (CPW fed is presented. This antenna only used one layer and the patch antenna is constructed on the first layer and back to back with CPW fed and bottom part is ground plane. The width notch is used to achieve the UWB characteristic. The results shown that the impedance bandwidth is 1130 MHz (1.662–2.792 GHz or about 50.7% for VSWR <2.

  11. Measurement of mortar permittivity during setting using a coplanar waveguide

    International Nuclear Information System (INIS)

    Juan-García, P; Torrents, J M

    2010-01-01

    A sensor based on a coplanar waveguide structure was designed to perform non-destructive tests for material characterization in which the measurement can be done only on one side of the sample. The measurements were compared with the impedance of a capacitor filled with the same material. The permittivity and insertion loss of the sensor showed valuable information about the setting process of a mortar slab during the first 28 days of the hardening process, and a good correlation between both measurements was obtained, so the proposed setup can be useful for structural surveillance and moisture detection in civil structures

  12. Coplanar Electrode Layout Optimized for Increased Sensitivity for Electrical Impedance Spectroscopy

    Directory of Open Access Journals (Sweden)

    Casper Hyttel Clausen

    2014-12-01

    Full Text Available This work describes an improvement in the layout of coplanar electrodes for electrical impedance spectroscopy. We have developed, fabricated, and tested an improved electrode layout, which improves the sensitivity of an impedance flow cytometry chip. The improved chip was experimentally tested and compared to a chip with a conventional electrode layout. The improved chip was able to discriminate 0.5 μm beads from 1 μm as opposed to the conventional chip. Furthermore, finite element modeling was used to simulate the improvements in electrical field density and uniformity between the electrodes of the new electrode layout. Good agreement was observed between the model and the obtained experimental results.

  13. Dynamical history of coplanar two-satellite systems

    International Nuclear Information System (INIS)

    Ruskol, E.L.; Nikolajeva, E.V.; Syzdykov, A.S.

    1975-01-01

    One of the possible early states of the Earth-Moon system was a system of several large satellites around the Earth. The dynamical evolution of coplanar three-body systems is studied; a planet (Earth) and two massive satellites (proto-moons) with geocentric orbits of slightly different radii. Such configurations may arise in multiple satellite systems receding from a planet due to tidal friction. The numerical integration of the equations of motion shows that initially circular Keplerian orbits are soon transformed into disturbed elliptic orbits which are intersecting. The life-time of such a coplanar system between two probable physical collisions of satellites is roughly from one day to one year for satellite systems with radii less than 20 R(Earth), and may reach 100 yr for three-dimensional systems. This time-scale is short in comparison with the duration of the removal of satellites due to tides raised on the planet, which is estimated as 10 6 -10 8 yr for the same orbital dimensions. Therefore, the life-time of a system of several proto-moons is mainly determined by their tidal interactions with the Earth. For conditions which we have considered, the most probable result of the evolution was coalescence of satellites as the consequence of the collisions. (Auth.)

  14. Radiation dose in critical organs due to non-coplanar irradiation of the pituitary gland

    International Nuclear Information System (INIS)

    Schulte, R.W.M.; Rittmann, K.L.; Meinass, H.J.; Rennicke, P.

    1996-01-01

    In order to estimate the somatic and genetic risk associated with a non-coplanar linac-based radiation technique of the pituitary gland, systematic secondary-dose measurements in a phantom and sample measurements of the dose near critical organs of patients were performed. For measurements of the dose outside the primary radiation field an acrylic-PVC phantom was used which was irradiated with a single field (4x4 cm 2 ). Eight patients with pituitary tumors were treated isocentrically with a combination of sagittal and transverse rotational arcs. To measure the dose in critical organs, LiF thermoluminescence dosimeters (TLD) in chip form were placed onto 1 eyelid, the skin over the thyroid, and the patient's clothes covering the region of breasts and ovaries of female patients and the testicles of male patients. Measurements were performed for all patients during 1 sagittal irradiation and for the majority of patients during 1 transverse irradiation. The phantom measurements demonstrated that the secondary dose measured on the patients surface can be considered as a good approximation for the dose in adjacent organs. The median dose in critical organs for sagittal irradiation was in the range of 25.8 mGy (eyes) to 1.9 mGy (testicles), and for transverse irradiation in the range of 23.3 mGy (eyes) to 1.3 mGy (testicles). The ratio of median organ doses for sagittal and transverse irradiation was 2.1 for the thyroid gland, 1.1 for the eyes, and 1.5 for the other organs. The dose in critical organs due to non-coplanar irradiation of the pituitary gland is only a small fraction of the dose delivered to the reference point of the planning target volume. The risk of a radiation-induced tumor and a genetic consequence associated with these small doses is generally less than 1% and 0.1%, respectively. (orig./MG) [de

  15. Energy flow analysis of out-of-plane vibration in coplanar coupled finite Mindlin plates

    Directory of Open Access Journals (Sweden)

    Young-Ho Park

    2015-01-01

    Full Text Available : In this paper, an Energy Flow Analysis (EFA for coplanar coupled Mindlin plates was performed to estimate their dynamic responses at high frequencies. Mindlin plate theory can consider the effects of shear distortion and rotatory inertia, which are very important at high frequencies. For EFA for coplanar coupled Mindlin plates, the wave transmission and reflection relationship for progressing out-of-plane waves (out-of-plane shear wave, bending dominant flexural wave, and shear dominant flexural wave in coplanar coupled Mindlin plates was newly derived. To verify the validity of the EFA results, numerical analyses were performed for various cases where coplanar coupled Mindlin plates are excited by a harmonic point force, and the energy flow solutions for coplanar coupled Mindlin plates were compared with the classical solutions in the various conditions.

  16. Observing electron spin resonance between 0.1 and 67 GHz at temperatures between 50 mK and 300 K using broadband metallic coplanar waveguides

    Science.gov (United States)

    Wiemann, Yvonne; Simmendinger, Julian; Clauss, Conrad; Bogani, Lapo; Bothner, Daniel; Koelle, Dieter; Kleiner, Reinhold; Dressel, Martin; Scheffler, Marc

    2015-05-01

    We describe a fully broadband approach for electron spin resonance (ESR) experiments, where it is possible to tune not only the magnetic field but also the frequency continuously over wide ranges. Here, a metallic coplanar transmission line acts as compact and versatile microwave probe that can easily be implemented in different cryogenic setups. We perform ESR measurements at frequencies between 0.1 and 67 GHz and at temperatures between 50 mK and room temperature. Three different types of samples (Cr3+ ions in ruby, organic radicals of the nitronyl-nitroxide family, and the doped semiconductor Si:P) represent different possible fields of application for the technique. We demonstrate that an extremely large phase space in temperature, magnetic field, and frequency for ESR measurements, substantially exceeding the range of conventional ESR setups, is accessible with metallic coplanar lines.

  17. SU-F-BRB-10: A Statistical Voxel Based Normal Organ Dose Prediction Model for Coplanar and Non-Coplanar Prostate Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tran, A; Yu, V; Nguyen, D; Woods, K; Low, D; Sheng, K [UCLA, Los Angeles, CA (United States)

    2015-06-15

    Purpose: Knowledge learned from previous plans can be used to guide future treatment planning. Existing knowledge-based treatment planning methods study the correlation between organ geometry and dose volume histogram (DVH), which is a lossy representation of the complete dose distribution. A statistical voxel dose learning (SVDL) model was developed that includes the complete dose volume information. Its accuracy of predicting volumetric-modulated arc therapy (VMAT) and non-coplanar 4π radiotherapy was quantified. SVDL provided more isotropic dose gradients and may improve knowledge-based planning. Methods: 12 prostate SBRT patients originally treated using two full-arc VMAT techniques were re-planned with 4π using 20 intensity-modulated non-coplanar fields to a prescription dose of 40 Gy. The bladder and rectum voxels were binned based on their distances to the PTV. The dose distribution in each bin was resampled by convolving to a Gaussian kernel, resulting in 1000 data points in each bin that predicted the statistical dose information of a voxel with unknown dose in a new patient without triaging information that may be collectively important to a particular patient. We used this method to predict the DVHs, mean and max doses in a leave-one-out cross validation (LOOCV) test and compared its performance against lossy estimators including mean, median, mode, Poisson and Rayleigh of the voxelized dose distributions. Results: SVDL predicted the bladder and rectum doses more accurately than other estimators, giving mean percentile errors ranging from 13.35–19.46%, 4.81–19.47%, 22.49–28.69%, 23.35–30.5%, 21.05–53.93% for predicting mean, max dose, V20, V35, and V40 respectively, to OARs in both planning techniques. The prediction errors were generally lower for 4π than VMAT. Conclusion: By employing all dose volume information in the SVDL model, the OAR doses were more accurately predicted. 4π plans are better suited for knowledge-based planning than

  18. Ionisation differential cross section measurements for N2 at low incident energy in coplanar and non-coplanar geometries

    International Nuclear Information System (INIS)

    Sakaamini, Ahmad; Murray, Andrew James; Amami, Sadek; Madison, Don; Ning, Chuangang

    2016-01-01

    Ionisation triple differential cross sections have been determined experimentally and theoretically for the neutral molecule N 2 over a range of geometries from coplanar to the perpendicular plane. Data were obtained at incident electron energies ∼10 and ∼20 eV above the ionisation potential of the 3 σ g , 1 π u and 2 σ g states, using both equal and non-equal outgoing electron energies. The data were taken with the incident electron beam in the scattering plane ( ψ = 0°), at 45° to this plane and orthogonal to the plane ( ψ = 90°). The set of nine measured differential cross sections at a given energy were then inter-normalised to each other. The data are compared to new calculations using various distorted wave methods, and differences between theory and experiment are discussed. (paper)

  19. Coplanar capacitance sensors for detecting water intrusion in composite structures

    International Nuclear Information System (INIS)

    Nassr, Amr A; El-Dakhakhni, Wael W; Ahmed, Wael H

    2008-01-01

    Composite materials are becoming more affordable and widely used for retrofitting, rehabilitating and repairing reinforced concrete structures designed and constructed under older specifications. However, the mechanical properties and long-term durability of composite materials may degrade severely in the presence of water intrusion. This study presents a new non-destructive evaluation (NDE) technique for detecting the water intrusion in composite structures by evaluating the dielectric properties of different composite system constituent materials. The variation in the dielectric signatures was employed to design a coplanar capacitance sensor with high sensitivity to detect such defects. An analytical model was used to study the effect of the sensor geometry on the output signal and to optimize sensor design. A finite element model was developed to validate analytical results and to evaluate other sensor design-related parameters. Experimental testing of a concrete specimen wrapped with composite laminate and containing a series of pre-induced water intrusion defects was conducted in order to validate the concept of the new technique. Experimental data showed excellent agreement with the finite element model predictions and confirmed sensor performance

  20. Limits of dose escalation in lung cancer: a dose-volume histogram analysis comparing coplanar and non-coplanar techniques

    Energy Technology Data Exchange (ETDEWEB)

    Derycke, S; Van Duyse, B; Schelfhout, J; De Neve, W

    1995-12-01

    To evaluate the feasibility of dose escalation in radiotherapy of inoperable lung cancer, a dose-volume histogram analysis was performed comparing standard coplanar (2D) with non-coplanar (3D) beam arrangements on a non-selected group of 20 patients planned by Sherouse`s GRATISTM 3D-planning system. Serial CT-scanning was performed and 2 Target Volumes (Tvs) were defined. Gross Tumor Volume (GTV) defined a high-dose Target Volume (TV-1). GTV plus location of node stations with > 10% probability of invasion (Minet et al.) defined an intermediate-dose Target Volume (TV-2). However, nodal regions which are incompatible with cure were excluded from TV-2. These are ATS-regions 1, 8, 9 and 14 all left and right as well as heterolateral regions. For 3D-planning, Beam`s Eye View selected (by an experienced planner) beam arrangements were optimised using Superdot, a method of target dose-gradient annihilation developed by Sherouse. A second 3D-planning was performed using 4 beam incidences with maximal angular separation. The linac`s isocenter for the optimal arrangement was located at the geometrical center of gravity of a tetraheder, the tetraheder`s comers being the consecutive positions of the virtual source. This ideal beam arrangement was approximated as close as possible, taking into account technical limitations (patient-couch-gantry collisions). Criteria for tolerance were met if no points inside the spinal cord exceeded 50 Gy and if at least 50% of the lung volume received less than 20Gy. If dose regions below 50 Gy were judged acceptable at TV-2, 2D- as well as 3D-plans allow safe escalation to 80 Gy at TV-1. When TV-2 needed to be encompassed by isodose surfaces exceeding 50Gy, 3D-plans were necessary to limit dose at the spinal cord below tolerance. For large TVs dose is limited by lung tolerance for 3D-plans. An analysis (including NTCP-TCP as cost functions) of rival 3D-plans is being performed.

  1. Coplanar amorphous-indium-gallium-zinc-oxide thin film transistor with He plasma treated heavily doped layer

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ho-young [Advanced Display Research Center, Department of Information Display, Kyung Hee University, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); LG Display R and D Center, 245 Lg-ro, Wollong-myeon, Paju-si, Gyeonggi-do 413-811 (Korea, Republic of); Lee, Bok-young; Lee, Young-jang; Lee, Jung-il; Yang, Myoung-su; Kang, In-byeong [LG Display R and D Center, 245 Lg-ro, Wollong-myeon, Paju-si, Gyeonggi-do 413-811 (Korea, Republic of); Mativenga, Mallory; Jang, Jin, E-mail: jjang@khu.ac.kr [Advanced Display Research Center, Department of Information Display, Kyung Hee University, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of)

    2014-01-13

    We report thermally stable coplanar amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) with heavily doped n{sup +} a-IGZO source/drain regions. Doping is through He plasma treatment in which the resistivity of the a-IGZO decreases from 2.98 Ω cm to 2.79 × 10{sup −3} Ω cm after treatment, and then it increases to 7.92 × 10{sup −2} Ω cm after annealing at 300 °C. From the analysis of X-ray photoelectron spectroscopy, the concentration of oxygen vacancies in He plasma treated n{sup +}a-IGZO does not change much after thermal annealing at 300 °C, indicating thermally stable n{sup +} a-IGZO, even for TFTs with channel length L = 4 μm. Field-effect mobility of the coplanar a-IGZO TFTs with He plasma treatment changes from 10.7 to 9.2 cm{sup 2}/V s after annealing at 300 °C, but the performance of the a-IGZO TFT with Ar or H{sub 2} plasma treatment degrades significantly after 300 °C annealing.

  2. Coplanar amorphous-indium-gallium-zinc-oxide thin film transistor with He plasma treated heavily doped layer

    International Nuclear Information System (INIS)

    Jeong, Ho-young; Lee, Bok-young; Lee, Young-jang; Lee, Jung-il; Yang, Myoung-su; Kang, In-byeong; Mativenga, Mallory; Jang, Jin

    2014-01-01

    We report thermally stable coplanar amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) with heavily doped n + a-IGZO source/drain regions. Doping is through He plasma treatment in which the resistivity of the a-IGZO decreases from 2.98 Ω cm to 2.79 × 10 −3 Ω cm after treatment, and then it increases to 7.92 × 10 −2 Ω cm after annealing at 300 °C. From the analysis of X-ray photoelectron spectroscopy, the concentration of oxygen vacancies in He plasma treated n + a-IGZO does not change much after thermal annealing at 300 °C, indicating thermally stable n + a-IGZO, even for TFTs with channel length L = 4 μm. Field-effect mobility of the coplanar a-IGZO TFTs with He plasma treatment changes from 10.7 to 9.2 cm 2 /V s after annealing at 300 °C, but the performance of the a-IGZO TFT with Ar or H 2 plasma treatment degrades significantly after 300 °C annealing

  3. Global pollution monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), furans (PCDFs) and coplanar polychlorinated biphenyls (coplanar PCBs) using skipjack tuna as bioindicator

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Daisuke [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Watanabe, Mafumi [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Subramanian, Annamalai [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Tanaka, Hiroyuki [National Research Institute of Fisheries and Environment of Inland Sea (Japan); Fillmann, Gilberto [Fundacao Universidade Federal do Rio Grande (Brazil); Lam, Paul K.S. [Department of Biology and Chemistry, City University of Hong Kong, Hong Kong (China); Zheng, Gene J. [Department of Biology and Chemistry, City University of Hong Kong, Hong Kong (China); Muchtar, Muswerry [Research and Development Center for Oceanology, Indonesian Institute of Sciences (Indonesia); Razak, Hamidah [Research and Development Center for Oceanology, Indonesian Institute of Sciences (Indonesia); Prudente, Maricar [Science Education Department, De La Salle University (Philippines); Chung, Kyu-Hyuck [College of Pharmacy, Sungkyunkwan University (Korea, Republic of); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan)]. E-mail: shinsuke@agr.ehime-u.ac.jp

    2005-07-15

    In order to elucidate the global distribution of dioxins and related compounds, such as PCDDs, PCDFs and coplanar PCBs, levels of these compounds were determined in the muscle of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters and open seas near Japan, Taiwan, Philippines, Indonesia, Seychelles and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Indian Ocean and the North Pacific Ocean. PCDDs, PCDFs and coplanar PCBs were detected in almost all the specimens collected from all the locations surveyed, indicating widespread contamination by these compounds in the marine environment. Higher concentrations of dioxins and coplanar PCBs were detected in the samples from temperate Asian regions, plausibly due to larger usage and anthropogenic generation in highly industrialized countries around the East China Sea and the South China Sea, such as Japan, Korea, Taiwan, Hong Kong and coastal China. - Global pollution monitoring of PCDD/Fs and coplanar PCBs in offshore water and open sea were conducted using skipjack tuna as bioindicator.

  4. Global pollution monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), furans (PCDFs) and coplanar polychlorinated biphenyls (coplanar PCBs) using skipjack tuna as bioindicator

    International Nuclear Information System (INIS)

    Ueno, Daisuke; Watanabe, Mafumi; Subramanian, Annamalai; Tanaka, Hiroyuki; Fillmann, Gilberto; Lam, Paul K.S.; Zheng, Gene J.; Muchtar, Muswerry; Razak, Hamidah; Prudente, Maricar; Chung, Kyu-Hyuck; Tanabe, Shinsuke

    2005-01-01

    In order to elucidate the global distribution of dioxins and related compounds, such as PCDDs, PCDFs and coplanar PCBs, levels of these compounds were determined in the muscle of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters and open seas near Japan, Taiwan, Philippines, Indonesia, Seychelles and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Indian Ocean and the North Pacific Ocean. PCDDs, PCDFs and coplanar PCBs were detected in almost all the specimens collected from all the locations surveyed, indicating widespread contamination by these compounds in the marine environment. Higher concentrations of dioxins and coplanar PCBs were detected in the samples from temperate Asian regions, plausibly due to larger usage and anthropogenic generation in highly industrialized countries around the East China Sea and the South China Sea, such as Japan, Korea, Taiwan, Hong Kong and coastal China. - Global pollution monitoring of PCDD/Fs and coplanar PCBs in offshore water and open sea were conducted using skipjack tuna as bioindicator

  5. Miniature Coplanar Implantable Antenna on Thin and Flexible Platform for Fully Wireless Intracranial Pressure Monitoring System

    Directory of Open Access Journals (Sweden)

    M. Waqas A. Khan

    2017-01-01

    Full Text Available Minimally invasive approach to intracranial pressure monitoring is desired for long-term diagnostics. The monitored pressure is transmitted outside the skull through an implant antenna. We present a new miniature (6 mm × 5 mm coplanar implant antenna and its integration on a sensor platform to establish a far-field data link for the sensor readout at distances of 0.5 to 1 meter. The implant antenna was developed using full-wave electromagnetic simulator and measured in a liquid phantom mimicking the dielectric properties of the human head. It achieved impedance reflection coefficient better than −10 dB from 2.38 GHz to 2.54 GHz which covers the targeted industrial, scientific, and medical band. Experiments resulted in an acceptable peak gain of approximately −23 dBi. The implant antenna was submerged in the liquid phantom and interfaced to a 0.5 mW voltage controlled oscillator. To verify the implant antenna performance as a part of the ICP monitoring system, we recorded the radiated signal strength using a spectrum analyzer. Using a half-wavelength dipole as the receiving antenna, we captured approximately −58.7 dBm signal at a distance of 1 m from the implant antenna which is well above for the reader with sensitivity of −80 dBm.

  6. Usefulness of Non-coplanar Helical Tomotherapy Using Variable Axis Baseplate

    International Nuclear Information System (INIS)

    Ha, Jin Sook; Chung, Yoon Sun; Lee, Ik Jae; Shin, Dong Bong; Kim, Jong Dae; Kim, Sei Joon; Jeon, Mi Jin; Chok, Yoon Jin; Kim, Ki Kwang; Lee, Seul Bee

    2011-01-01

    Helical Tomotherapy allows only coplanar beam delivery because it does not allow couch rotation. We investigated a method to introduce non-coplanar beam by tilting a patient's head for Tomotherapy. The aim of this study was to compare intrafractional movement during Tomotherapy between coplanar and non-coplanar patient's setup. Helical Tomotherapy was used for treating eight patients with intracranial tumor. The subjects were divided into three groups: one group (coplanar) of 2 patients who lay on S-plate with supine position and wore thermoplastic mask for immobilizing the head, second group (non-coplanar) of 3 patients who lay on S-plate with supine position and whose head was tilted with Variable Axis Baseplate and wore thermoplastic mask, and third group (non-coplanar plus mouthpiece) of 3 patients whose head was tilted and wore a mouthpiece immobilization device and thermoplastic mask. The patients were treated with Tomotherapy after treatment planning with Tomotherapy Planning System. Megavoltage computed tomography (MVCT) was performed before and after treatment, and the intrafractional error was measured with lateral(X), longitudinal(Y), vertical(Z) direction movements and vector (√x 2 +√y 2 +√z 2 ) value for assessing overall movement. Intrafractional error was compared among three groups by taking the error of MVCT taken after the treatment. As the correction values (X, Y, Z) between MVCT image taken after treatment and CT-simulation image are close to zero, the patient movement is small. When the mean values of movement of each direction for non-coplanar setup were compared with coplanar setup group, X-axis movement was decreased by 13%, but Y-axis and Z-axis movement were increased by 109% and 88%, respectively. Movements of Y-axis and Z-axis with non-coplanar setup were relatively greater than that of X-axis since a tilted head tended to slip down. The mean of X-axis movement of the group who used a mouthpiece was greater by 9.4% than the group

  7. LE «SOTTIGLIEZZE DI CERTA DIDATTICA SUPERLATIVA» DELLA GRAMMATICA ELEMENTARE: STORIA (ATTESTATA DEL METODO RAFFORZISTA (1814-1914

    Directory of Open Access Journals (Sweden)

    Michela Dota

    2018-03-01

    Full Text Available Il contributo ripercorre la storia e le peculiarità del metodo rafforzista, metodo glottodidattico per l’insegnamento della lettura e della scrittura. Il metodo, nato in Italia nel primo Ottocento, nell’epoca postunitaria era praticato nelle scuole elementari soprattutto dell’Italia meridionale, nonché nelle scuole reggimentali e in alcuni istituti per sordomuti. Le sue fondamenta, aberranti rispetto alla norma ortografica e ortoepica tradizionale, lo resero obiettivo di un tenace ostracismo da parte del Ministero dell’Istruzione pubblica, sostenuto per questa occasione da due tra i più eminenti glottologi dell’epoca: Graziadio Isaia Ascoli e Francesco Lorenzo Pullè. Il metodo finì per estinguersi nel secondo decennio del Novecento.   The history of the “metodo rafforzista” for teaching Italian (1814-1914 This article retraces the history and peculiarities of the “metodo rafforzista”, a language teaching method developed in Italy during the first part of 1800s. In the post-Unitarian period, it was used in elementary schools, especially in Southern Italy, and also in military schools and in some institutes for the Deaf and Dumb. Orthographic and orthoepic models proposed by the “metodo rafforzista” diverged from rules of traditional Italian grammar. The method, supported by Graziadio Isaia Ascoli and Francesco Lorenzo Pullè, two of the most distinguished Italian linguists at that time, was subsequently rejected by the Ministry of Public Education, and it vanished during the second half of 1900s.

  8. Foetal uptake of coplanar polychlorinated biphenyl (PCB) congeners in mice

    International Nuclear Information System (INIS)

    Darnerud, P.O.; Sinjari, T.; Joensson, C.J.

    1996-01-01

    Earlier studies have shown that the Ah-receptor binding polychlorinated biphenyl (PCB) congener 3,3',4,4'-tetrachlorobiphenyl (IUPAC number CB-77) accumulated as hydroxy and methylsulphone metabolites in late gestational mice foetuses. In the present paper the foetal accumulation potential in mice of other dioxin-like PCB congeners was studied: 3,3'4,4',4-pentachlorobiphenyl, 3,3'4,4'5,5'-hexachlorobiphenyl and 2,3,3',4,4'-pentachlorobiphenyl (IUPAC numbers CB-126, CB-169, CB-105, to some extent dioxin-like) were compared to results of CB-77 (all congeners 14 C-labelled and in equimolar doses (2.0 μmol/kg body wt.)). CB-77 resulted in the comparatively strongest foetal 14 C-accumulation, when measured in plasma or whole body homogenate four days after administration (day 17 of pregnancy); the plasma 14 C-values (calculated as pmol/g wet wt.) were 760, 130, 60 and 40 for CB-77, -126, 105 and -169, respectively, and the CB-77 derived radioactivity in the foetal compartment was 3.6% of administered dose (i.e. a considerable portion of the remaining maternal body radioactivity). Thin-layer chromatography (TLC) results, suggesting extensive CB-77 metabolism and foetal metabolite uptake, support earlier findings. The effects of CB-77 and CB-169 on foetal 7-ethoxyresorufin-O-deethylase (EROD) activities (day 17 of gestation; two days after 5 mg/kg body wt. dose (14.0-17.0 μmol/kg body wt.)) was about 20 times lower than of CB-126. In the dam, high radioactivity levels were observed int he liver and fat (highest concentrations found in CB-126 and CB-105, respectively). Strain comparison - foetal 14 C-uptake (four days after administration of CB-77) in C57BL mice was almost five times higher than in NMRI - may be correlated to earlier observed differences in EROD activities between these strains. The present results indicate that congener and strain differences exist regarding both foetal and maternal distribution patterns of coplanar PCB congeners and point out the

  9. Numerical and Analytical Study of Optimal Low-Thrust Limited-Power Transfers between Close Circular Coplanar Orbits

    Directory of Open Access Journals (Sweden)

    Sandro da Silva Fernandes

    2007-01-01

    Full Text Available A numerical and analytical study of optimal low-thrust limited-power trajectories for simple transfer (no rendezvous between close circular coplanar orbits in an inverse-square force field is presented. The numerical study is carried out by means of an indirect approach of the optimization problem in which the two-point boundary value problem, obtained from the set of necessary conditions describing the optimal solutions, is solved through a neighboring extremal algorithm based on the solution of the linearized two-point boundary value problem through Riccati transformation. The analytical study is provided by a linear theory which is expressed in terms of nonsingular elements and is determined through the canonical transformation theory. The fuel consumption is taken as the performance criterion and the analysis is carried out considering various radius ratios and transfer durations. The results are compared to the ones provided by a numerical method based on gradient techniques.

  10. Triple differential cross-sections of Ne (2s2) in coplanar to perpendicular plane geometry

    Science.gov (United States)

    Chen, L. Q.; Khajuria, Y.; Chen, X. J.; Xu, K. Z.

    2003-10-01

    The distorted wave Born approximation (DWBA) with the spin averaged static exchange potential has been used to calculate the triple differential cross-sections (TDCSs) for Ne (2s^2) ionization by electron impact in coplanar to perpendicular plane symmetric geometry at 110.5 eV incident electron energy. The present theoretical results at gun angles Psi = 0^circ (coplanar symmetric geometry) and Psi = 90^circ (perpendicular plane geometry) are in satisfactory agreement with the available experimental data. A deep interference minimum appears in the TDCS in the coplanar symmetric geometry and a strong peak at scattering angle xi = 90^circ caused by the single collision mechanism has been observed in the perpendicular plane geometry. The TDCSs at the gun angles Psi = 30^circ, and Psi = 60^circ are predicted.

  11. Coplanar-grid CdZnTe detector with three-dimensional position sensitivity

    International Nuclear Information System (INIS)

    Luke, P.N.; Amman, M.; Lee, J.S.; Yaver, H.

    1998-06-01

    A 3-dimensional position-sensitive coplanar-grid detector design for use with compound semiconductors is described. This detector design maintains the advantage of a coplanar-grid detector in which good energy resolution can be obtained from materials with poor charge transport. Position readout in two dimensions is accomplished using proximity-sensing electrodes adjacent to the electron-collecting grid electrode of the detector. Additionally, depth information is obtained by taking the ratio of the amplitudes of the collecting grid signal and the cathode signal. Experimental results from a prototype CdZnTe detector are presented

  12. Beam’s-eye-view imaging during non-coplanar lung SBRT

    Energy Technology Data Exchange (ETDEWEB)

    Yip, Stephen S. F., E-mail: syip@lroc.harvard.edu; Rottmann, Joerg; Berbeco, Ross I. [Department of Radiation Oncology, Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2015-12-15

    Purpose: Beam’s-eye-view (BEV) imaging with an electronic portal imaging device (EPID) can be performed during lung stereotactic body radiation therapy (SBRT) to monitor the tumor location in real-time. Image quality for each patient and treatment field depends on several factors including the patient anatomy and the gantry and couch angles. The authors investigated the angular dependence of automatic tumor localization during non-coplanar lung SBRT delivery. Methods: All images were acquired at a frame rate of 12 Hz with an amorphous silicon EPID. A previously validated markerless lung tumor localization algorithm was employed with manual localization as the reference. From ten SBRT patients, 12 987 image frames of 123 image sequences acquired at 48 different gantry–couch rotations were analyzed. δ was defined by the position difference of the automatic and manual localization. Results: Regardless of the couch angle, the best tracking performance was found in image sequences with a gantry angle within 20° of 250° (δ = 1.40 mm). Image sequences acquired with gantry angles of 150°, 210°, and 350° also led to good tracking performances with δ = 1.77–2.00 mm. Overall, the couch angle was not correlated with the tracking results. Among all the gantry–couch combinations, image sequences acquired at (θ = 30°, ϕ = 330°), (θ = 210°, ϕ = 10°), and (θ = 250°, ϕ = 30°) led to the best tracking results with δ = 1.19–1.82 mm. The worst performing combinations were (θ = 90° and 230°, ϕ = 10°) and (θ = 270°, ϕ = 30°) with δ > 3.5 mm. However, 35% (17/48) of the gantry–couch rotations demonstrated substantial variability in tracking performances between patients. For example, the field angle (θ = 70°, ϕ = 10°) was acquired for five patients. While the tracking errors were ≤1.98 mm for three patients, poor performance was found for the other two patients with δ ≥ 2.18 mm, leading to average tracking error of 2.70 mm. Only one

  13. Observing electron spin resonance between 0.1 and 67 GHz at temperatures between 50 mK and 300 K using broadband metallic coplanar waveguides

    International Nuclear Information System (INIS)

    Wiemann, Yvonne; Simmendinger, Julian; Clauss, Conrad; Bogani, Lapo; Dressel, Martin; Scheffler, Marc; Bothner, Daniel; Koelle, Dieter; Kleiner, Reinhold

    2015-01-01

    We describe a fully broadband approach for electron spin resonance (ESR) experiments, where it is possible to tune not only the magnetic field but also the frequency continuously over wide ranges. Here, a metallic coplanar transmission line acts as compact and versatile microwave probe that can easily be implemented in different cryogenic setups. We perform ESR measurements at frequencies between 0.1 and 67 GHz and at temperatures between 50 mK and room temperature. Three different types of samples (Cr 3+ ions in ruby, organic radicals of the nitronyl-nitroxide family, and the doped semiconductor Si:P) represent different possible fields of application for the technique. We demonstrate that an extremely large phase space in temperature, magnetic field, and frequency for ESR measurements, substantially exceeding the range of conventional ESR setups, is accessible with metallic coplanar lines

  14. Observing electron spin resonance between 0.1 and 67 GHz at temperatures between 50 mK and 300 K using broadband metallic coplanar waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Wiemann, Yvonne; Simmendinger, Julian; Clauss, Conrad; Bogani, Lapo; Dressel, Martin; Scheffler, Marc [1. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart (Germany); Bothner, Daniel; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut and Center for Collective Quantum Phenomena in LISA+, Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen (Germany)

    2015-05-11

    We describe a fully broadband approach for electron spin resonance (ESR) experiments, where it is possible to tune not only the magnetic field but also the frequency continuously over wide ranges. Here, a metallic coplanar transmission line acts as compact and versatile microwave probe that can easily be implemented in different cryogenic setups. We perform ESR measurements at frequencies between 0.1 and 67 GHz and at temperatures between 50 mK and room temperature. Three different types of samples (Cr{sup 3+} ions in ruby, organic radicals of the nitronyl-nitroxide family, and the doped semiconductor Si:P) represent different possible fields of application for the technique. We demonstrate that an extremely large phase space in temperature, magnetic field, and frequency for ESR measurements, substantially exceeding the range of conventional ESR setups, is accessible with metallic coplanar lines.

  15. Measuring the complex permittivity tensor of uniaxial biological materials with coplanar waveguide transmission line

    Science.gov (United States)

    A simple and accurate technique is described for measuring the uniaxial permittivity tensor of biological materials with a coplanar waveguide transmission-line configuration. Permittivity tensor results are presented for several chicken and beef fresh meat samples at 2.45 GHz....

  16. Low-temperature hydrogenation of diamond nanoparticles using diffuse coplanar surface barrier discharge at atmospheric pressure

    Czech Academy of Sciences Publication Activity Database

    Kromka, Alexander; Čech, J.; Kozak, Halyna; Artemenko, Anna; Ižák, Tibor; Čermák, Jan; Rezek, Bohuslav; Černák, M.

    2015-01-01

    Roč. 252, č. 11 (2015), s. 2602-2607 ISSN 0370-1972 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:68378271 Keywords : atmospheric plasma * diamond nanoparticles * diffuse coplanar surface barrier discharge * FTIR * XPS Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.522, year: 2015

  17. Radical production efficiency and electrical characteristics of a coplanar barrier discharge built by multilayer ceramic technology

    DEFF Research Database (Denmark)

    Jõgi, Indrek; Erme, Kalev; Levoll, Erik

    2017-01-01

    The present study investigated the electrical characteristics and radical production efficiency of a coplanar barrier discharge (CBD) device manufactured by Kyocera by multilayer ceramic technology. The device consisted of a number of linear electrodes with electrode and gap widths of 0.75 mm...

  18. Design and modeling of inductors, capacitors and coplanar waveguides at tens of GHz frequencies

    CERN Document Server

    Aryan, Naser Pour

    2015-01-01

    This book describes the basic principles of designing and modelling inductors, MIM capacitors and coplanar waveguides at frequencies of several tens of GHz. The author explains the design and modelling of key, passive elements, such as capacitors, inductors and transmission lines that enable high frequency MEMS operating at frequencies in the orders of tens of GHz.

  19. Non-coplanar volumetric-modulated arc therapy (VMAT) for craniopharyngiomas reduces radiation doses to the bilateral hippocampus: a planning study comparing dynamic conformal arc therapy, coplanar VMAT, and non-coplanar VMAT

    International Nuclear Information System (INIS)

    Uto, Megumi; Mizowaki, Takashi; Ogura, Kengo; Hiraoka, Masahiro

    2016-01-01

    Recent studies suggest that radiation-induced injuries to the hippocampus play important roles in compromising neurocognitive functioning for patients with brain tumors and it could be important to spare the hippocampus using modern planning methods for patients with craniopharyngiomas. As bilateral hippocampus are located on the same level as the planning target volume (PTV) in patients with craniopharyngioma, it seems possible to reduce doses to hippocampus using non-coplanar beams. While the use of non-coplanar beams in volumetric-modulated arc therapy (VMAT) of malignant intracranial tumors has recently been reported, no dosimetric comparison has yet been made between VMAT using non-coplanar arcs (ncVMAT) and VMAT employing only coplanar arcs (coVMAT) among patients with craniopharyngiomas. We performed a planning study comparing dose distributions to the PTV, hippocampus, and other organs at risk (OAR) of dynamic conformal arc therapy (DCAT), coVMAT, and ncVMAT. DCAT, coVMAT, and ncVMAT plans were created for 10 patients with craniopharyngiomas. The prescription dose was 52.2 Gy in 29 fractions, and 99 % of each PTV was covered by 90 % of the prescribed dose. The maximum dose was held below 107 % of the prescribed dose. CoVMAT and ncVMAT plans were formulated to satisfy the following criteria: the doses to the hippocampus were minimized, and the doses to the OAR were similar to or lower than those of DCAT. The mean equivalent doses in 2-Gy fractions to 40 % of the volumes of the bilateral hippocampus [EQD 2 (40% hippos )] were 15.4/10.8/6.5 Gy for DCAT/coVMAT/ncVMAT, respectively. The EQD 2 (40% hippos ) for ncVMAT were <7.3 Gy, which is the threshold predicting cognitive impairment, as defined by Gondi et al.. The mean doses to normal brain tissue and the conformity indices were similar for the three plans, and the homogeneity indices were significantly better for coVMAT and ncVMAT compared with DCAT. NcVMAT is more appropriate than DCAT and coVMAT for

  20. Dynamic intensity-modulated non-coplanar arc radiotherapy (INCA) for head and neck cancer

    International Nuclear Information System (INIS)

    Krayenbuehl, Jerome; Davis, J. Bernard; Ciernik, I. Frank

    2006-01-01

    Background and purpose: To define the potential advantages of intensity-modulated radiotherapy (IMRT) applied using a non-coplanar dynamic arc technique for the treatment of head and neck cancer. Materials and methods: External beam radiotherapy (EBRT) was planned in ten patients with head and neck cancer using coplanar IMRT and non-coplanar arc techniques, termed intensity modulated non-coplanar arc EBRT (INCA). Planning target volumes (PTV1) of first order covered the gross tumor volume and surrounding clinical target volume treated with 68-70 Gy, whereas PTV2 covered the elective lymph nodes with 54-55 Gy using a simultaneous internal boost. Treatment plan comparison between IMRT and INCA was carried out using dose-volume histogram and 'equivalent uniform dose' (EUD). Results: INCA resulted in better dose coverage and homogeneity of the PTV1, PTV2, and reduced dose delivered to most of the organs at risk (OAR). For the parotid glands, a reduction of the mean dose of 2.9 (±2.0) Gy was observed (p 0.002), the mean dose to the larynx was reduced by 6.9 (±2.9) Gy (p 0.003), the oral mucosa by 2.4 (±1.1) Gy (p < 0.001), and the maximal dose to the spinal cord by 3.2 (±1.7) Gy (p = 0.004). The mean dose to the brain was increased by 3.0 (±1.4) Gy (p = 0.002) and the mean lung dose increased by 0.2 (±0.4) Gy (p = 0.87). The EUD suggested better avoidance of the OAR, except for the lung, and better coverage and dose uniformity were achieved with INCA compared to IMRT. Conclusion: Dose delivery accuracy with IMRT using a non-coplanar dynamic arc beam geometry potentially improves treatment of head and neck cancer

  1. Global pollution monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), furans (PCDFs) and coplanar polychlorinated biphenyls (coplanar PCBs) using skipjack tuna as bioindicator

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, D.; Watanabe, M.; Subraminian, A.N.; Tanabe, S. [Ehime Univ. (Japan); Tanaka, H. [National Research Inst. of Fisheries and Environment of Inland Sea (Japan); Fillmann, G. [Fundacao Univ. Federal do Rio Grande (Brazil); Lam, P.K.S.; Zheng, G.J. [City Univ. of Hong Kong (Hong Kong); Muchtar, M.; Razak, H. [Indonesian Inst. of Sciences (Indonesia); Prudente, M. [De La Salle Univ. (Philippines); Chung, K. [Sungkyunkwan Univ. (Korea)

    2004-09-15

    Worldwide contamination by dioxins and related compounds, such as polychlorinated dibenzop- dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (coplanar PCBs) representing persistent organic pollutants (POPs) have been of great concern due to their persistency in the environment, highly bioaccumulative nature and adverse effects on wildlife and humans. Several studies on air samples and marine organisms from open seas suggested a long range transport of these compounds through atomosphere. Although several investigators have monitored dioxins pollution in localized areas, information on the global distribution of dioxins which can explain their atomospheric transport, behavior and fate are still limited. Skipjack tuna is primarily distributed from offshore waters to open seas in tropical and temperate regions almost all over the world such as the Pacific, Atlantic and Indian Oceans6. This species is an important commercial fish and its ecology and biology has been well studied. Moreover, suitability of skipjack tuna for global monitoring of organic pollutants (DDTs, HCHs PBDEs, organotins, etc.) has been established in our previous report, indicating that migration pattern, growth stage and sex of these animals have no or little effect on the variations of POPs residue levels in their bodies. Hence this species reflected POPs pollution levels in seawater when and where they were collected, caused by the rapid equilibrium partitioning between seawater and body lipid. These facts made skipjack tuna a suitable bioindicator for monitoring the contamination status of dioxins and related compounds. The objectives of this study are to elucidate the global distribution of dioxins (PCDD/Fs and coplanar PCBs) in offshore waters and open seas, and to understand the transport and behaviour of these chemicals using skipjack tuna as bioindicator.

  2. A reverse method to estimate initial temperatures in geothermal reservoirs; Un metodo inverso para estimacion de la temperatura inicial de yacimientos geotermicos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Gutierrez, Alfonso [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Cuernavaca, Morelos (Mexico)]. E-mail: aggarcia@iie.org.mx; Ramos Alcantara, Jose R. [Centro Nacional de Investigacion y Desarrollo Tecnologico, Departamento de Ingenieria Mecanica, Cuernavaca, Morelos (Mexico); Arellano Gomez, Victor M. [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Cuernavaca, Morelos (Mexico)

    2010-01-15

    A method is presented for estimating the initial temperature in geothermal-reservoir formations. The method is based on control theory where the measured temperatures or temperature logs are compared with corresponding simulated temperatures for different times with the well closed. The comparison is made using a control algorithm that makes changes to the originally assumed reservoir temperatures and performs iterations until the best fit between the temperature logs and the simulated temperatures is obtained. The simulation of fluid transport and heat in the well includes the processes of circulation and stop in the presence of circulation losses, modeled on macroscopic balances of momentum and energy. The transport processes in the formation regard the reservoir as an isotropic porous medium and fluid flow is described by Darcy's law. This model generates the fields of temperatures, pressures and speeds as a function of time and space. The method was tested with data from well LV-3 in Las Tres Virgenes geothermal field, Baja California Sur, Mexico. The estimated temperatures of the undisturbed formation-or initial temperatures-are compared within {+-}15 degrees Celsius with the measured temperatures, which is an acceptable outcome from an engineering point of view. [Spanish] Se presenta un metodo para la estimacion de la temperatura inicial en las formaciones de yacimientos geotermicos. El metodo se basa en la teoria de control donde las temperaturas medidas o registros de temperatura se comparan con las correspondientes temperaturas simuladas a diferentes tiempos con el pozo cerrado. La comparacion se hace usando un algoritmo de control el cual hace cambios a las temperaturas de yacimiento originalmente supuestas y realiza iteraciones hasta que se obtiene el mejor ajuste entre los registros de temperatura y las temperaturas simuladas. La simulacion del transporte de fluidos y calor en el pozo incluye los procesos de circulacion y paro en presencia de

  3. Second-order Born effect in coplanar doubly symmetric (e,2e) collisions for sodium

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yang; Jiao, Liguang [Center for Theoretical Atomic and Molecular Physics, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080 (China); Zhou, Yajun, E-mail: yajunzhou2003@yahoo.com.cn [Center for Theoretical Atomic and Molecular Physics, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080 (China)

    2012-06-18

    The second-order distorted wave Born approximation (DWBA) method is employed to investigate the triple differential cross sections (TDCS) of coplanar doubly symmetric (e,2e) collisions for alkali target sodium at excess energies of 6–60 eV. Comparing with the first-order DWBA calculations, the inclusion of second-order Born term in the scattering amplitude improves the degree of agreement with experiments, especially for backward scattering region of TDCS. This indicates the present second-order Born term is capable to give a reasonable correction to DWBA model in studying coplanar symmetric (e,2e) problems in low and intermediate energy range. -- Highlights: ► We consider second-order Born effect in (e,2e) collisions for sodium. ► Our second-order term gives a correct description on the multi scattering process. ► Our second-order DWBA model improves the agreement between theory and experiment.

  4. Analysis of a Segmented Annular Coplanar Capacitive Tilt Sensor with Increased Sensitivity

    Directory of Open Access Journals (Sweden)

    Jiahao Guo

    2016-01-01

    Full Text Available An investigation of a segmented annular coplanar capacitor is presented. We focus on its theoretical model, and a mathematical expression of the capacitance value is derived by solving a Laplace equation with Hankel transform. The finite element method is employed to verify the analytical result. Different control parameters are discussed, and each contribution to the capacitance value of the capacitor is obtained. On this basis, we analyze and optimize the structure parameters of a segmented coplanar capacitive tilt sensor, and three models with different positions of the electrode gap are fabricated and tested. The experimental result shows that the model (whose electrode-gap position is 10 mm from the electrode center realizes a high sensitivity: 0.129 pF/° with a non-linearity of <0.4% FS (full scale of ±40°. This finding offers plenty of opportunities for various measurement requirements in addition to achieving an optimized structure in practical design.

  5. Analysis of a Segmented Annular Coplanar Capacitive Tilt Sensor with Increased Sensitivity.

    Science.gov (United States)

    Guo, Jiahao; Hu, Pengcheng; Tan, Jiubin

    2016-01-21

    An investigation of a segmented annular coplanar capacitor is presented. We focus on its theoretical model, and a mathematical expression of the capacitance value is derived by solving a Laplace equation with Hankel transform. The finite element method is employed to verify the analytical result. Different control parameters are discussed, and each contribution to the capacitance value of the capacitor is obtained. On this basis, we analyze and optimize the structure parameters of a segmented coplanar capacitive tilt sensor, and three models with different positions of the electrode gap are fabricated and tested. The experimental result shows that the model (whose electrode-gap position is 10 mm from the electrode center) realizes a high sensitivity: 0.129 pF/° with a non-linearity of design.

  6. Co-planar deformation and thermal propagation behavior in a bundle burst test

    International Nuclear Information System (INIS)

    Uetsuka, Hiroshi; Koizumi, Yasuo; Kawasaki, Satoru

    1980-07-01

    The probability of the suggested feedback mechanism which could lead to co-planar deformation in a bundle burst test was assessed by the data of test and the calculation based on simplified model. Following four points were evaluated. (1) The probability of local deformation during early heat up stage. (2) The relation between the characteristic of heater and the feedback mechanism. (3) Thermal propagation behavior between two adjacent rods during heat up stage. (4) The propagation of ballooning in a bundle. The probability of suggested feedback mechanism was denied in all the evaluation. The feedback mechanism suggested by Burman could not be a controlling mechanism in co-planar deformation in a bundle burst test. (author)

  7. Non-coplanar automatic beam orientation selection in cranial IMRT: a practical methodology

    Energy Technology Data Exchange (ETDEWEB)

    Llacer, Jorge [EC Engineering Consultants LLC, 130 Forest Hill Drive, Los Gatos, CA 95032 (United States); Li Sicong [Department of Radiation Oncology, University of Nebraska Medical Center, Omaha, NE 68198 (United States); Agazaryan, Nzhde; Solberg, Timothy D [Department of Radiation Oncology, University of California, Los Angeles, CA 90095 (United States); Promberger, Claus [BrainLAB AG, Kapellenstrasse 12, 85622 Feldkirchen (Germany)], E-mail: escalivat@jllacer.com, E-mail: sl1@unmc.edu, E-mail: NAgazaryan@mednet.ucla.edu, E-mail: claus.promberger@brainlab.com, E-mail: Timothy.Solberg@utsouthwestern.edu

    2009-03-07

    This paper proposes a method for automatic selection of beam orientations in non-coplanar cranial IMRT. Methods of computer vision, beam's eye view techniques and neural networks are used to define a new geometry-based methodology that leads to treatment plans for cranial lesions that are comparable in quality to those generated by experienced radiation physicists. The automatic beam selection (ABS) process can be carried out in clinically useful computation times, in 1 min or less for most cases. In the process of describing the ABS process, it is shown that the cranial beam orientation optimization problem is mathematically ill posed, with the expectation that a large number of solutions will lead to similar results. Nevertheless, there are better and worse solutions and we show that the proposed ABS process, by its design, has to lead to one of the better ones. We have carried out extensive tests with 14 patients with beam selection tasks ranging from the rather simple to quite complex. The ABS process has always yielded optimizations with results that are considered good for clinic use. Seven-beam coplanar optimizations for some of the patients have also been investigated. Comparisons with non-coplanar optimizations indicate in which cases the simpler coplanar plans can be used to advantage. Parameters used in the comparisons are dose-volume histograms, minimum and maximum PTV doses, equivalent uniform doses for the PTV and OARs, and treatment volume, conformity and normal tissue indices. It is felt that the current ABS methodology is ready for extensive clinical tests.

  8. Analysis of a Segmented Annular Coplanar Capacitive Tilt Sensor with Increased Sensitivity

    OpenAIRE

    Jiahao Guo; Pengcheng Hu; Jiubin Tan

    2016-01-01

    An investigation of a segmented annular coplanar capacitor is presented. We focus on its theoretical model, and a mathematical expression of the capacitance value is derived by solving a Laplace equation with Hankel transform. The finite element method is employed to verify the analytical result. Different control parameters are discussed, and each contribution to the capacitance value of the capacitor is obtained. On this basis, we analyze and optimize the structure parameters of a segmented...

  9. PCDDs, PCDFs, and coplanar PCBs in albatross from the North Pacific and Southern Oceans: levels, patterns, and toxicological implications.

    Science.gov (United States)

    Tanabe, Shinsuke; Watanabe, Mafumi; Minh, Tu Binh; Kunisue, Tatsuya; Nakanishi, Shigeyuki; Ono, Hitoshi; Tanaka, Hiroyuki

    2004-01-15

    Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (coplanar PCBs) were determined in five albatross species collected from the North Pacific and Southern Oceans to assess the north-south differences in residue levels, accumulation patterns, and toxic potential. Black-footed and Laysan albatrosses from the North Pacific Ocean contained higher levels of PCDD/Fs and coplanar PCBs than albatrosses from the Southern Ocean, indicating that emission sources of these contaminants were predominant in the northern hemisphere. Residue levels in albatrosses from the remote North Pacific Ocean far from the point source of pollution were comparable to or higher than those in terrestrial and coastal birds from contaminated areas in developed nations, suggesting the specific exposure and accumulation of PCDD/Fs and coplanar PCBs in albatross. The long life span and ingestion of plastic resin pellets by albatrosses could be the plausible explanations for the elevated accumulation of persistent and lipophilic contaminants including PCDD/Fs and coplanar PCBs in these birds. Relative proportions of PCDFs and coplanar PCBs in albatross were higher than those observed in birds inhabiting terrestrial and coastal areas, suggesting that these toxic chemicals may have higher transportability by air and water than PCDDs. Congener patterns of PCDD/Fs in albatross showed less variability as compared to those in terrestrial species, indicating that contamination patterns of PCDD/Fs were similar within the open ocean environment. Contributions of PCDD/Fs to total TEQs in albatrosses from the open ocean were generally lower than those in terrestrial birds, suggesting different toxic potency of PCDD/Fs and coplanar PCBs on animals inhabiting open ocean and terrestrial environment. Whereas albatrosses from southern oceans retained lower TEQ concentrations, possible adverse effects of PCDD/Fs and coplanar PCBs

  10. Design and performance evaluation of a coplanar multimodality scanner for rodent imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lage, E; Vaquero, J J; Sisniega, A; Tapias, G; Abella, M; Rodriguez-Ruano, A; Desco, M [Unidad de Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Espana, S [Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Ciencias Fisicas, Universidad Complutense, Madrid (Spain); Ortuno, J E [Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza (Spain); Udias, A [Departamento de Estadistica e Investigacion Operativa, Universidad Rey Juan Carlos, Fuenlabrada (Spain)], E-mail: elage@mce.hggm.es

    2009-09-21

    This work reports on the development and performance evaluation of the VrPET/CT, a new multimodality scanner with coplanar geometry for in vivo rodent imaging. The scanner design is based on a partial-ring PET system and a small-animal CT assembled on a rotatory gantry without axial displacement between the geometric centers of both fields of view (FOV). We report on the PET system performance based on the NEMA NU-4 protocol; the performance characteristics of the CT component are not included herein. The accuracy of inter-modality alignment and the imaging capability of the whole system are also evaluated on phantom and animal studies. Tangential spatial resolution of PET images ranged between 1.56 mm at the center of the FOV and 2.46 at a radial offset of 3.5 cm. The radial resolution varies from 1.48 mm to 1.88 mm, and the axial resolution from 2.34 mm to 3.38 mm for the same positions. The energy resolution was 16.5% on average for the entire system. The absolute coincidence sensitivity is 2.2% for a 100-700 keV energy window with a 3.8 ns coincident window. The scatter fraction values for the same settings were 11.45% for a mouse-sized phantom and 23.26% for a rat-sized phantom. The peak noise equivalent count rates were also evaluated for those phantoms obtaining 70.8 kcps at 0.66 MBq/cc and 31.5 kcps at 0.11 MBq/cc, respectively. The accuracy of inter-modality alignment is below half the PET resolution, and the image quality of biological specimens agrees with measured performance parameters. The assessment presented in this study shows that the VrPET/CT system is a good performance small-animal imager, while the cost derived from a partial ring detection system is substantially reduced as compared with a full-ring PET tomograph.

  11. PLATFORM DEFORMATION PHASE CORRECTION FOR THE AMiBA-13 COPLANAR INTERFEROMETER

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Yu-Wei; Lin, Kai-Yang; Huang, Yau-De; Ho, Paul T. P.; Chen, Ming-Tang; Locutus Huang, Chih-Wei; Koch, Patrick M.; Nishioka, Hiroaki; Umetsu, Keiichi; Han, Chih-Chiang; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Proty Wu, Jiun-Huei; Cheng, Tai-An; Fu, Szu-Yuan; Wang, Fu-Cheng [Department of Physics, Institute of Astrophysics, and Center for Theoretical Sciences, National Taiwan University, Taipei 10617, Taiwan (China); Liu, Guo-Chin [Department of Physics, Tamkang University, 251-37 Tamsui, New Taipei City, Taiwan (China); Molnar, Sandor M. [Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, Taipei 10617, Taiwan (China); Chang, Yu-Yen, E-mail: ywliao@asiaa.sinica.edu.tw, E-mail: jhpw@phys.ntu.edu.tw [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)

    2013-05-20

    We present a new way to solve the platform deformation problem of coplanar interferometers. The platform of a coplanar interferometer can be deformed due to driving forces and gravity. A deformed platform will induce extra components into the geometric delay of each baseline and change the phases of observed visibilities. The reconstructed images will also be diluted due to the errors of the phases. The platform deformations of The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) were modeled based on photogrammetry data with about 20 mount pointing positions. We then used the differential optical pointing error between two optical telescopes to fit the model parameters in the entire horizontal coordinate space. With the platform deformation model, we can predict the errors of the geometric phase delays due to platform deformation with a given azimuth and elevation of the targets and calibrators. After correcting the phases of the radio point sources in the AMiBA interferometric data, we recover 50%-70% flux loss due to phase errors. This allows us to restore more than 90% of a source flux. The method outlined in this work is not only applicable to the correction of deformation for other coplanar telescopes but also to single-dish telescopes with deformation problems. This work also forms the basis of the upcoming science results of AMiBA-13.

  12. Development of gas ionization chambers with coplanar electrodes for alpha-ray spectrometry

    International Nuclear Information System (INIS)

    Iwasaki, Kenta; Tanaka, Naomichi; Murakami, Kohei; Hasebe, Nobuyuki; Kusano, Hiroki; Shibamura, Eido; Miyajima, Mitsuhiro

    2016-01-01

    A large-area alpha-ray spectrometer is required to measure the low level alpha emitters in environmental samples, which may be distributed in the vicinity of nuclear power plants. A gas ionization chamber with a coplanar electrode has attractive features such as with mechanical ruggedness, easy handling, easy fabrication of large electrode, and relatively well-known performance. We have investigated the performance of a gas ionization chamber with a coplanar electrode for alpha-ray spectrometry, particularly in the energy resolution. The present experiment shows that the energy resolution in the full width at half maximum (FWHM) is 129 keV (= 2.7%) for alpha-rays from Np with an energy of 4.78 MeV, 120 keV (= 2.2%) for those with 5.49 MeV from Am, and 109 keV (= 1.9%) for those with 5.81 MeV from Cm. It is found that the energy resolution obtained at the present experiment is dominated in the electronic noise caused by the large capacitance existed between the collecting anode (CA) and non-collecting anode (NCA) in the coplanar electrode. (author)

  13. Coplanar UHF RFID tag antenna with U-shaped inductively coupled feed for metallic applications.

    Directory of Open Access Journals (Sweden)

    Karrar Naji Salman

    Full Text Available In this paper, we present a novel compact, coplanar, tag antenna design for metallic objects. Electrically small antenna has designed for a UHF RFID (860-960 MHz based on a proximity-coupled feed through. Furthermore, two symmetrical Via-loaded coplanar grounds fed by a U-shaped inductively coupled feed through an embedded transmission line. This configuration results in an antenna with dimensions of 31 × 19.5 × 3.065 mm3 at 915 MHz, and the total gain for the antenna is 0.12 dBi. The Via-loaded coplanar and U-shaped inductively coupled feeds allow the antenna to provide flexible tuning in terms of antenna impedance. In addition, a figure of merit is applied for the proposed tag antenna, and the results are presented. The read range is measured to be 4.2 m, which is very close to simulated values. This antenna measurement shows very good agreement with simulations.

  14. Conception and characterization of a virtual coplanar grid for a 11×11 pixelated CZT detector

    Energy Technology Data Exchange (ETDEWEB)

    Espagnet, Romain; Frezza, Andrea [Department of Physics, Engineering Physics and Optics and Cancer Research Center, Université Laval, Quebec city, QC, Canada G1R 0A6 (Canada); Martin, Jean-Pierre; Hamel, Louis-André [Department of Physics, Université de Montréal, C.P. 6128 Montréal QC, Canada H3C 3J7 (Canada); Després, Philippe, E-mail: philippe.despres@phy.ulaval.ca [Department of Physics, Engineering Physics and Optics and Cancer Research Center, Université Laval, Quebec city, QC, Canada G1R 0A6 (Canada); Department of Radiation Oncology and Research Center of CHU de Québec - Université Laval, Quebec city, QC Canada G1R 2J6 (Canada)

    2017-07-11

    Due to the low mobility of holes in CZT, commercially available detectors with a relatively large volume typically use a pixelated anode structure. They are mostly used in imaging applications and often require a dense electronic readout scheme. These large volume detectors are also interesting for high-sensitivity applications and a CZT-based blood gamma counter was developed from a 20×20×15 mm{sup 3} crystal available commercially and having a 11×11 pixelated readout scheme. A method is proposed here to reduce the number of channels required to use the crystal in a high-sensitivity counting application, dedicated to pharmacokinetic modelling in PET and SPECT. Inspired by a classic coplanar anode, an implementation of a virtual coplanar grid was done by connecting the 121 pixels of the detector to form intercalated bands. The layout, the front-end electronics and the characterization of the detector in this 2-channel anode geometry is presented. The coefficients required to compensate for electron trapping in CZT were determined experimentally to improve the performance. The resulting virtual coplanar detector has an intrinsic efficiency of 34% and an energy resolution of 8% at 662 keV. The detector's response was linear between 80 keV and 1372 keV. This suggests that large CZT crystals offer an excellent alternative to scintillation detectors for some applications, especially those where high-sensitivity and compactness are required.

  15. Josephson effect in Al/Bi{sub 2}Se{sub 3}/Al coplanar hybrid devices

    Energy Technology Data Exchange (ETDEWEB)

    Galletti, L., E-mail: luca.galletti@unina.it [Dipartimento di Scienze Fisiche, Università degli Studi di Napoli Federico II, I-80126 Napoli (Italy); CNR-SPIN Napoli, Complesso Universitario di Monte Sant’Angelo, 80126 Napoli (Italy); Charpentier, S. [Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296 Göteborg (Sweden); Lucignano, P.; Massarotti, D. [Dipartimento di Scienze Fisiche, Università degli Studi di Napoli Federico II, I-80126 Napoli (Italy); CNR-SPIN Napoli, Complesso Universitario di Monte Sant’Angelo, 80126 Napoli (Italy); Arpaia, R. [Dipartimento di Scienze Fisiche, Università degli Studi di Napoli Federico II, I-80126 Napoli (Italy); Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296 Göteborg (Sweden); Tafuri, F. [CNR-SPIN Napoli, Complesso Universitario di Monte Sant’Angelo, 80126 Napoli (Italy); Dipartimento di Ingegneria Industriale e dell’Informazione, Seconda Università di Napoli, I-81031 Aversa (CE) (Italy); Bauch, T. [Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296 Göteborg (Sweden); Suzuki, Y. [University of Tsukuba, Institute of Materials Science, Tsukuba 305, Ibaraki (Japan); Tagliacozzo, A. [Dipartimento di Scienze Fisiche, Università degli Studi di Napoli Federico II, I-80126 Napoli (Italy); Kadowaki, K. [University of Tsukuba, Institute of Materials Science, Tsukuba 305, Ibaraki (Japan); Lombardi, F. [Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296 Göteborg (Sweden)

    2014-08-15

    Highlights: • Superconducting proximity effect induced in Al/Bi{sub 2}Se{sub 3}/Al coplanar hybrid devices. • Comparative study of Al/Bi{sub 2}Se{sub 3} interfaces with various buffer layers. • Towards a Josephson super-current through the edge states of topological insulators. - Abstract: The edge states of Topological Insulators (TI) are protected against backscattering, thanks to the topological properties arising from their band structure. Coupling a TI to a superconductor (S) can induce unconventional effects, including the creation of Majorana bound states (MBS). The fabrication of coplanar hybrid devices is a fundamental step to pave the way to the understanding of proximity effects in topologically non-trivial systems, and to a large variety of experiments aimed at the possible detection of MBS. We discuss the feasibility and some relevant properties of Al–Bi{sub 2}Se{sub 3}–Al coplanar proximity devices. Special attention is devoted to the design of the junction, aimed at enhancing the coupling between the electrodes and the TI.

  16. Vision Servo Motion Control and Error Analysis of a Coplanar XXY Stage for Image Alignment Motion

    Directory of Open Access Journals (Sweden)

    Hau-Wei Lee

    2013-01-01

    Full Text Available In recent years, as there is demand for smart mobile phones with touch panels, the alignment/compensation system of alignment stage with vision servo control has also increased. Due to the fact that the traditional stacked-type XYθ stage has cumulative errors of assembly and it is heavy, it has been gradually replaced by the coplanar stage characterized by three actuators on the same plane with three degrees of freedom. The simplest image alignment mode uses two cameras as the equipments for feedback control, and the work piece is placed on the working stage. The work piece is usually engraved/marked. After the cameras capture images and when the position of the mark in the camera is obtained by image processing, the mark can be moved to the designated position in the camera by moving the stage and using alignment algorithm. This study used a coplanar XXY stage with 1 μm positioning resolution. Due to the fact that the resolution of the camera is about 3.75 μm per pixel, thus a subpixel technology is used, and the linear and angular alignment repeatability of the alignment system can achieve 1 μm and 5 arcsec, respectively. The visual servo motion control for alignment motion is completed within 1 second using the coplanar XXY stage.

  17. PLATFORM DEFORMATION PHASE CORRECTION FOR THE AMiBA-13 COPLANAR INTERFEROMETER

    International Nuclear Information System (INIS)

    Liao, Yu-Wei; Lin, Kai-Yang; Huang, Yau-De; Ho, Paul T. P.; Chen, Ming-Tang; Locutus Huang, Chih-Wei; Koch, Patrick M.; Nishioka, Hiroaki; Umetsu, Keiichi; Han, Chih-Chiang; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter; Proty Wu, Jiun-Huei; Cheng, Tai-An; Fu, Szu-Yuan; Wang, Fu-Cheng; Liu, Guo-Chin; Molnar, Sandor M.; Chang, Yu-Yen

    2013-01-01

    We present a new way to solve the platform deformation problem of coplanar interferometers. The platform of a coplanar interferometer can be deformed due to driving forces and gravity. A deformed platform will induce extra components into the geometric delay of each baseline and change the phases of observed visibilities. The reconstructed images will also be diluted due to the errors of the phases. The platform deformations of The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) were modeled based on photogrammetry data with about 20 mount pointing positions. We then used the differential optical pointing error between two optical telescopes to fit the model parameters in the entire horizontal coordinate space. With the platform deformation model, we can predict the errors of the geometric phase delays due to platform deformation with a given azimuth and elevation of the targets and calibrators. After correcting the phases of the radio point sources in the AMiBA interferometric data, we recover 50%-70% flux loss due to phase errors. This allows us to restore more than 90% of a source flux. The method outlined in this work is not only applicable to the correction of deformation for other coplanar telescopes but also to single-dish telescopes with deformation problems. This work also forms the basis of the upcoming science results of AMiBA-13.

  18. Platform Deformation Phase Correction for the AMiBA-13 Coplanar Interferometer

    Science.gov (United States)

    Liao, Yu-Wei; Lin, Kai-Yang; Huang, Yau-De; Proty Wu, Jiun-Huei; Ho, Paul T. P.; Chen, Ming-Tang; Locutus Huang, Chih-Wei; Koch, Patrick M.; Nishioka, Hiroaki; Cheng, Tai-An; Fu, Szu-Yuan; Liu, Guo-Chin; Molnar, Sandor M.; Umetsu, Keiichi; Wang, Fu-Cheng; Chang, Yu-Yen; Han, Chih-Chiang; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter

    2013-05-01

    We present a new way to solve the platform deformation problem of coplanar interferometers. The platform of a coplanar interferometer can be deformed due to driving forces and gravity. A deformed platform will induce extra components into the geometric delay of each baseline and change the phases of observed visibilities. The reconstructed images will also be diluted due to the errors of the phases. The platform deformations of The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) were modeled based on photogrammetry data with about 20 mount pointing positions. We then used the differential optical pointing error between two optical telescopes to fit the model parameters in the entire horizontal coordinate space. With the platform deformation model, we can predict the errors of the geometric phase delays due to platform deformation with a given azimuth and elevation of the targets and calibrators. After correcting the phases of the radio point sources in the AMiBA interferometric data, we recover 50%-70% flux loss due to phase errors. This allows us to restore more than 90% of a source flux. The method outlined in this work is not only applicable to the correction of deformation for other coplanar telescopes but also to single-dish telescopes with deformation problems. This work also forms the basis of the upcoming science results of AMiBA-13.

  19. Diagnostics of pre-breakdown light emission in a helium coplanar barrier discharge: the presence of neutral bremsstrahlung

    Science.gov (United States)

    Navrátil, Zdeněk; Morávek, Tomáš; Ráheľ, Jozef; Čech, Jan; Lalinský, Ondřej; Trunec, David

    2017-05-01

    Weak light emission (˜10-3 of active discharge signal; average count rate ˜ 1 photon s-1 nm-1) associated with surface charge relaxation during the dark phase of a helium diffuse coplanar barrier discharge was studied by optical emission spectroscopy, using a technique of phase-resolved single photon counting. The optical emission spectra of the dark phase contained luminescent bands of the dielectrics used (Al2O3, AlN) and spectral lines from the gas constituents (OH*, {{{N}}}2* , {{{N}}}2+* , He*, He{}2* , O*). During the charge relaxation event, a broad continuum appeared in the optical emission spectra, consisting of bremsstrahlung radiation and amplified luminescence of the dielectric barrier. The analysis presented suggests that the bremsstrahlung radiation originated from slow electrons colliding with neutral helium atoms. The fitting procedure we developed reproduced well the observed shape of the continuum. Moreover, it provided a method for the determination of electric field strength in the discharge during this particular phase. The electric field reached 1 kV cm-1 during the charge relaxation event.

  20. Variation on the magnetic field profiles of transmission lines for various surrounding conditions calculated by the finite element method; Variacion de los perfiles de campo magnetico en lineas de transmision en diversas condiciones del entorno calculadas mediante el metodo de elementos finitos

    Energy Technology Data Exchange (ETDEWEB)

    Ponta, Fernando; Ferreira, Fabiana

    2001-07-01

    This paper applies the finite element method for the calculation of line magnetic field transversal profile using own routine calculation. Using a real case, simulations were performed under various conditions gathering distortion elements, obtaining the field profile. By analysing these results conclusions are drawing related to the changes produced by the distortions on the magnetic field configuration and evaluations of the surrounding elements influence are evaluated.

  1. Three-Dimensional Non-Coplanar Conformal Radiotherapy Yields Better Results Than Traditional Beam Arrangements for Adjuvant Treatment of Gastric Cancer

    International Nuclear Information System (INIS)

    Soyfer, Viacheslav; Corn, Benjamin W.; Melamud, Alex B.S.; Alani, Shlomi; Tempelhof, Haim; Agai, Reuben; Shmueli, Anat; Figer, Arie; Kovner, Felix

    2007-01-01

    Purpose: The current standard of adjuvant treatment for gastric cancer after curative resection is concurrent administration of radiotherapy and 5-fluorouracil-based chemotherapy. The radiation fields are often arranged as anterioposterior-posteroanterior opposed parallel fields with general recommendations for sparing at least two-thirds of one kidney. We investigated whether a better radiation distribution would be achievable with three-dimensional conformal approaches compared with the classic anterioposterior-posteroanterior fields. Methods and Materials: A total of 19 patients with adenocarcinoma of the stomach were treated with adjuvant chemoradiotherapy using a non-coplanar four-field arrangement. In each case, parallel planning using an anterioposterior-posteroanterior arrangement and a four-field 'box' was performed, and the generated plans were subsequently compared for coverage of target volumes and doses to irradiated organs next to the tumor bed. A separate analysis was performed for kidneys exposed to greater and lower doses in each patient. The mean radiation dose and percentage of kidney volume receiving a dose >20 Gy were registered. Statistical analysis was performed using the two-tailed t test. Results: The clinical target volume was adequately covered in all three plans. In the greater-dose kidney group, all the differences were statistically significant with a benefit for the three-dimensional plan. In the lower-dose kidney group, the differences in the mean radiation dose did not reach the level of statistical significance, and the differences in the kidney volume receiving a dose >20 Gy showed a statistically significant benefit for the three-dimensional plan. Conclusion: Non-coplanar three-dimensional-based conformal planning for postoperative radiotherapy for gastric cancer provided the best results regarding kidney and spinal cord exposure with adequate clinical target volume coverage. This technique was readily implemented in clinical

  2. Three-dimensional non-coplanar conformal radiotherapy yields better results than traditional beam arrangements for adjuvant treatment of gastric cancer.

    Science.gov (United States)

    Soyfer, Viacheslav; Corn, Benjamin W; Melamud, Alex; Alani, Shlomi; Tempelhof, Haim; Agai, Reuben; Shmueli, Anat; Figer, Arie; Kovner, Felix

    2007-10-01

    The current standard of adjuvant treatment for gastric cancer after curative resection is concurrent administration of radiotherapy and 5-fluorouracil-based chemotherapy. The radiation fields are often arranged as anterioposterior-posteroanterior opposed parallel fields with general recommendations for sparing at least two-thirds of one kidney. We investigated whether a better radiation distribution would be achievable with three-dimensional conformal approaches compared with the classic anterioposterior-posteroanterior fields. A total of 19 patients with adenocarcinoma of the stomach were treated with adjuvant chemoradiotherapy using a non-coplanar four-field arrangement. In each case, parallel planning using an anterioposterior-posteroanterior arrangement and a four-field "box" was performed, and the generated plans were subsequently compared for coverage of target volumes and doses to irradiated organs next to the tumor bed. A separate analysis was performed for kidneys exposed to greater and lower doses in each patient. The mean radiation dose and percentage of kidney volume receiving a dose >20 Gy were registered. Statistical analysis was performed using the two-tailed t test. The clinical target volume was adequately covered in all three plans. In the greater-dose kidney group, all the differences were statistically significant with a benefit for the three-dimensional plan. In the lower-dose kidney group, the differences in the mean radiation dose did not reach the level of statistical significance, and the differences in the kidney volume receiving a dose >20 Gy showed a statistically significant benefit for the three-dimensional plan. Non-coplanar three-dimensional-based conformal planning for postoperative radiotherapy for gastric cancer provided the best results regarding kidney and spinal cord exposure with adequate clinical target volume coverage. This technique was readily implemented in clinical practice.

  3. Effect of electron transport properties on unipolar CdZnTe radiation detectors: LUND, SpectrumPlus, and Coplanar Grid

    International Nuclear Information System (INIS)

    James, Ralph B.

    2000-01-01

    Device simulations of (1) the laterally-contacted-unipolar-nuclear detector (LUND), (2) the SpectrumPlus, (3) and the coplanar grid made of Cd 0.9 Zn 0.1 Te (CZT) were performed for 137 Cs irradiation by 662.15 keV gamma-rays. Realistic and controlled simulations of the gamma-ray interactions with the CZT material were done using the MCNP4B2 Monte Carlo program, and the detector responses were simulated using the Sandia three-dimensional multielectrode simulation program (SandTMSP). The simulations were done for the best and the worst expected carrier nobilities and lifetimes of currently commercially available CZT materials for radiation detector applications. For the simulated unipolar devices, the active device volumes were relatively large and the energy resolutions were fairly good, but these performance characteristics were found to be very sensitive to the materials properties. The internal electric fields, the weighting potentials, and the charge induced efficiency maps were calculated to give insights into the operation of these devices

  4. Validation of Hiriart equation to compute steam production by the lip pressure method; Validacion de la ecuacion de Hiriart para calculo de gasto de vapor por el metodo de presion de labio

    Energy Technology Data Exchange (ETDEWEB)

    Flores Armenta, Magaly [Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)

    1996-09-01

    Mainly in new geothermal wells, it is necessary to evaluate the production in a very fast, simple and not expensive way, to know the convenience to install surface equipment, such as silencers and separators, to drive the steam to the commercial gathering system. In practice, one of the most known methods is the lip pressure one, which requires a simple set of installations. The objective of this paper is to validate the steam flow rate calculated by the lip pressure method, with respect to the ASME method. The ASME method is known for its accuracy, and is done by measuring the steam and liquid after a high pressure separator, by an orifice plate of known diameter and a triangular weir. Results of the validation show up the feasibility of application of the lip pressure method by using a simple adjustment equation. Percentage of mistake results less than 1%, without any notable influence of the production enthalpy. That equation to be applied in a general case, is as follows: Q{nu} =(20642)(F*P*D{sup 2}/{radical}h-2000). For the particular case of the Los Azufres geothermal field, the equation is: Q{nu}= 810*P*D{sup 2} [Espanol] En los pozos geotermicos, principalmente en los nuevos, es necesario evaluar su produccion de manera rapida, sencilla y economica, para determinar la conveniencia de instalar equipo superficial, como separadores, silenciadores, etc., que permita la integracion del vapor al sistema comercial de generacion electrica. Para fines practicos uno de los metodos mas conocidos es el de presion de labio, que solo requiere un arreglo sencillo de instalaciones superficiales. En este documento se validan y ajustan los calculos de produccion de vapor por ese metodo de presion de labio, con respecto a las mediciones exactas efectuadas con el metodo ASME. Este ultimo es reconocido internacionalmente por su precision, y se lleva a cabo separando la mezcla obtenida en superficie en un recipiente a presion para medir el vapor a traves de una placa de orificio

  5. SU-E-T-436: Fluence-Based Trajectory Optimization for Non-Coplanar VMAT

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, G; Bamber, JC; Bedford, JL [Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London (United Kingdom); Evans, PM [Centre for Vision, Speech and Signal Processing, University of Surrey, Guildford (United Kingdom); Saran, FH; Mandeville, HC [The Royal Marsden NHS Foundation Trust, Sutton (United Kingdom)

    2015-06-15

    Purpose: To investigate a fluence-based trajectory optimization technique for non-coplanar VMAT for brain cancer. Methods: Single-arc non-coplanar VMAT trajectories were determined using a heuristic technique for five patients. Organ at risk (OAR) volume intersected during raytracing was minimized for two cases: absolute volume and the sum of relative volumes weighted by OAR importance. These trajectories and coplanar VMAT formed starting points for the fluence-based optimization method. Iterative least squares optimization was performed on control points 24° apart in gantry rotation. Optimization minimized the root-mean-square (RMS) deviation of PTV dose from the prescription (relative importance 100), maximum dose to the brainstem (10), optic chiasm (5), globes (5) and optic nerves (5), plus mean dose to the lenses (5), hippocampi (3), temporal lobes (2), cochleae (1) and brain excluding other regions of interest (1). Control point couch rotations were varied in steps of up to 10° and accepted if the cost function improved. Final treatment plans were optimized with the same objectives in an in-house planning system and evaluated using a composite metric - the sum of optimization metrics weighted by importance. Results: The composite metric decreased with fluence-based optimization in 14 of the 15 plans. In the remaining case its overall value, and the PTV and OAR components, were unchanged but the balance of OAR sparing differed. PTV RMS deviation was improved in 13 cases and unchanged in two. The OAR component was reduced in 13 plans. In one case the OAR component increased but the composite metric decreased - a 4 Gy increase in OAR metrics was balanced by a reduction in PTV RMS deviation from 2.8% to 2.6%. Conclusion: Fluence-based trajectory optimization improved plan quality as defined by the composite metric. While dose differences were case specific, fluence-based optimization improved both PTV and OAR dosimetry in 80% of cases.

  6. Finite Ground Coplanar (FGC) Waveguide: Characteristics and Advantages Evaluated for Radiofrequency and Wireless Communication Circuits

    Science.gov (United States)

    Ponchak, George E.

    1999-01-01

    Researchers in NASA Lewis Research Center s Electron Device Technology Branch are developing transmission lines for radiofrequency and wireless circuits that are more efficient, smaller, and make lower cost circuits possible. Traditionally, radiofrequency and wireless circuits have employed a microstrip or coplanar waveguide to interconnect the various electrical elements that comprise a circuit. Although a coplanar waveguide (CPW) is widely viewed as better than a microstrip for most applications, it too has problems. To solve these problems, NASA Lewis and the University of Michigan developed a new version of a coplanar waveguide with electrically narrow ground planes. Through extensive numerical modeling and experimental measurements, we have characterized the propagation constant of the FGC waveguide, the lumped and distributed circuit elements integrated in the FGC waveguide, and the coupling between parallel transmission lines. Although the attenuation per unit length is higher for the FGC waveguide because of higher conductor loss, the attenuation is comparable when the ground plane width is twice the center conductor width as shown in the following graph. An upper limit to the line width is derived from observations that when the total line width is greater than ld/2, spurious resonances due to the parallel plate waveguide mode are established. Thus, the ground plane width must be less than ld/4 where ld is the wavelength in the dielectric. Since the center conductor width S is typically less than l/10 to maintain good transverse electromagnetic mode characteristics, it follows that a ground plane width of B = 2S would also be electrically narrow. Thus, we can now treat the ground strips of the FGC waveguide the same way that the center conductor is treated.

  7. A comparison of dioxins, dibenzofurans and coplanar PCBs in uncooked and broiled ground beef, catfish and bacon.

    Science.gov (United States)

    Schecter, A; Dellarco, M; Päpke, O; Olson, J

    1998-01-01

    The primary source of dioxins (PCDDs), dibenzofurans (PCDFs) and coplanar PCBs for the general population is food, especially meat, fish, and dairy products. However, most data on the levels of these chemicals is from food in the raw or uncooked state. We report here the effect of one type of cooking (broiling) on the levels of PCDDs, PCDFs, and coplanar PCBs in ground beef (hamburger), bacon and catfish. Samples of hamburger, bacon, and catfish were broiled and compared to uncooked samples in order to measure changes in the amounts of dioxins in cooked food. The total amount of PCDD, PCDF, and coplanar PCB TEQ decreased by approximately 50% on average for each portion as a result of broiling the hamburger, bacon and catfish specimens. The mean concentration (pg TEQ/kg, wet weight) of PCDDs, PCDFs, and coplanar PCBs, however, remained the same in the hamburger, increased by 83% in the bacon, and decreased by 34% in the catfish. On average, the total measured concentration (pg/kg) of the congeners of PCDDs, PCDFs, and coplanar PCBs increased 14% in the hamburger, increased 29% in the bacon, and decreased 33% in the catfish.

  8. Factorized distorted wave approximation for the (e,2e) reaction on atoms : coplanar symmetric

    International Nuclear Information System (INIS)

    Fuss, I.; McCarthy, I.E.; Noble, C.J.; Weigold, E.

    1977-02-01

    The coplanar symmetric (e,2e) cross section has been studied in the intermediate energy region for the valence states of the inert gases He, Ar and Ne. Experimental measurements at 200, 400, 800, and 1200eV for He, and at 400, 800 and 1200eV for Ne and Ar, are compared with calculations based on the factorized half-off-shell distorted-wave impulse approximation. Calculations are carried out using partial wave expanded optical model wave functions which describe elastic scattering for the distorted waves, the eikonal approximation, and the plane wave approximation. (Author)

  9. DOLOČITEV POVRŠINSKE NAPETOSTI Z METODO KAPILARNEGA DVIGA DVOFAZNIH SISTEMOV

    OpenAIRE

    Kravanja, Gregor

    2014-01-01

    Namen magistrske naloge je bil postavitev merilne naprave in razvoj nove metode merjenja površinske napetosti s kapilarnim dvigom dvofaznih sistemov v okolici kritične točke. Za pridobitev natančnih in primerljivih meritev je bilo potrebno poznati natančni notranji premer tankih kapilar. Določili smo ga z metodo laserskega tipanja na nemški koordinatni merilni napravi ZEISS tipa UMC-850 s pomočjo merilne programske opreme CALYPSO 5.1.4. Za merjenje ravnotežne višine smo uporabili računalniški...

  10. FANSY 1.0: a phenomenological model for simulation of coplanar particle generation in superhigh-energy hadron interactions

    International Nuclear Information System (INIS)

    Mukhamedshin, Rauf

    2009-01-01

    Simulations show that a phenomenon of coplanarity of most energetic subcores of γ-ray-hadron families found in mountain-based and stratospheric X-ray-emulsion chamber experiments requires to introduce a coplanar particle generation with large transverse momenta in hadron interactions at superhigh energies. Some physical mechanisms are considered. A phenomenological model, which makes it possible to simulate the coplanar particle generation, is presented. Different versions of this model are considered, their features are described and compared with those of models applied by the CORSIKA package. Cosmic-ray experimental data and simulated results are compared. Conclusion on features of hadron interactions at superhigh energies and some predictions with respect to LHC experiments are made. (orig.) 3

  11. Comparison of a new noncoplanar intensity-modulated radiation therapy technique for craniospinal irradiation with 3 coplanar techniques

    DEFF Research Database (Denmark)

    Hansen, Anders T; Lukacova, Slavka; Lassen-Ramshad, Yasmin A.

    2015-01-01

    When standard conformal x-ray technique for craniospinal irradiation is used, it is a challenge to achieve satisfactory dose coverage of the target including the area of the cribriform plate, while sparing organs at risk. We present a new intensity-modulated radiation therapy (IMRT), noncoplanar...... patient using the noncoplanar IMRT-based technique, a coplanar IMRT-based technique, and a coplanar volumetric-modulated arch therapy (VMAT) technique. Dosimetry data for all patients were compared with the corresponding data from the conventional treatment plans. The new noncoplanar IMRT technique...... substantially reduced the mean dose to organs at risk compared with the standard radiation technique. The 2 other coplanar techniques also reduced the mean dose to some of the critical organs. However, this reduction was not as substantial as the reduction obtained by the noncoplanar technique. Furthermore...

  12. Design and Analysis of an Abbé Free Coplanar Stage

    Directory of Open Access Journals (Sweden)

    Chung Tien-Tung

    2017-01-01

    Full Text Available Design and analysis of a new Abbé free coplanar xy stage are presented in this paper. The xy stage is formed as conventional xy stages which combine with two stacked up linear guides. The x-guide is on the bottom and the y-guide is on top of the x-guide. The travel range of this xy stage is 300mm × 300mm, which fits dimensions of 12-inch wafers. A special mechanism is designed such that the z-surface of the y-guide has the same height as the z-surface of x-guide, and the Abbé error and cumulative error of this coplanar stage can be reduced. The concept of symmetric structure design is also considered to eliminate the structural deformation due to driving force of two guides. For this long travel range precision stage, the finite element method (FEM is applied to analyze the structural deformation and vibration natural frequencies. The requirement of structural deformation due to self-weight load is limited to 1.5μm, and first natural frequency is limited to over 100 Hz.

  13. Be discs in coplanar circular binaries: Phase-locked variations of emission lines

    Science.gov (United States)

    Panoglou, Despina; Faes, Daniel M.; Carciofi, Alex C.; Okazaki, Atsuo T.; Baade, Dietrich; Rivinius, Thomas; Borges Fernandes, Marcelo

    2018-01-01

    In this paper, we present the first results of radiative transfer calculations on decretion discs of binary Be stars. A smoothed particle hydrodynamics code computes the structure of Be discs in coplanar circular binary systems for a range of orbital and disc parameters. The resulting disc configuration consists of two spiral arms, and this can be given as input into a Monte Carlo code, which calculates the radiative transfer along the line of sight for various observational coordinates. Making use of the property of steady disc structure in coplanar circular binaries, observables are computed as functions of the orbital phase. Some orbital-phase series of line profiles are given for selected parameter sets under various viewing angles, to allow comparison with observations. Flat-topped profiles with and without superimposed multiple structures are reproduced, showing, for example, that triple-peaked profiles do not have to be necessarily associated with warped discs and misaligned binaries. It is demonstrated that binary tidal effects give rise to phase-locked variability of the violet-to-red (V/R) ratio of hydrogen emission lines. The V/R ratio exhibits two maxima per cycle; in certain cases those maxima are equal, leading to a clear new V/R cycle every half orbital period. This study opens a way to identifying binaries and to constraining the parameters of binary systems that exhibit phase-locked variations induced by tidal interaction with a companion star.

  14. Design and optimization of surface profilometer based on coplanar guide rail

    Science.gov (United States)

    Chen, Shuai; Dai, Yifan; Hu, Hao; Tie, Guipeng

    2017-10-01

    In order to implement the sub-micron precision measurement, a surface profilometer which based on the coplanar guide rail is designed. This profilometer adopts the open type air floating load and is driven by the magnetic force. As to achieve sub-micron accuracy, the flatness of granite guide working face and aerodynamic block are both processed to the micron level based on the homogenization of air flotation film theory. Permanent magnet which could reduce the influence of the driving disturbance to the measurement accuracy is used as the driving part. In this paper, the bearing capacity and the air floating stiffness of air floating block are both simulated and analyzed as to optimize the design parameters firstly. The layout and magnetic force of the magnet are also simulated. According to the simulation results, type selection and the position arrangement of the magnets are then confirmed. The test results on the experimental platform show that the surface profilometer based on coplanar guide rail possess the basis for realizing the submicron precision measurement.

  15. Performance of CdZnTe coplanar-grid gamma-ray detectors

    International Nuclear Information System (INIS)

    Luke, P.N.; Eissler, E.E.

    1995-11-01

    CdZnTe crystals grown using the high-pressure Bridgman method exhibit many properties that are desirable for radiation detector fabrication, such as high resistivity, stable operation, relative ease of processing, and the availability of large volume crystals. However, as is common with other compound semi-conductor materials, currently available CdZnTe crystals have poor charge transport characteristics. This seriously the spectral performance of detectors, especially in gamma-ray detection. The coplanar-grid detection technique was recently developed to address such charge collection problems. This technique was first demonstrated using a 5 mm cube CdZnTe detector, and a dramatic improvement in spectral response has been achieved. These early results verified the effectiveness of this technique and suggested that large-volume gamma-ray detectors with high energy resolution can be realized. To further the development of such detectors, it is important to understand the various factors that affect detector performance. The purpose of this paper is to examine the effects of material properties on the spectral performance of CdZnTe coplanar-grid detectors. Theoretical spectral response is to show the level of performance that can be achieved given the typical carrier mobility-lifetime (μτ) properties of present-day materials. Nonuniformity in the charge transport properties of the material, which could limit the energy resolution of the detectors, has been studied experimentally and some of the results are presented here

  16. 55 CANCRI: A COPLANAR PLANETARY SYSTEM THAT IS LIKELY MISALIGNED WITH ITS STAR

    International Nuclear Information System (INIS)

    Kaib, Nathan A.; Duncan, Martin J.; Raymond, Sean N.

    2011-01-01

    Although the 55 Cnc system contains multiple, closely packed planets that are presumably in a coplanar configuration, we use numerical simulations to demonstrate that they are likely to be highly inclined to their parent star's spin axis. Due to perturbations from its distant binary companion, this planetary system precesses like a rigid body about its parent star. Consequently, the parent star's spin axis and the planetary orbit normal likely diverged long ago. Because only the projected separation of the binary is known, we study this effect statistically, assuming an isotropic distribution for wide binary orbits. We find that the most likely projected spin-orbit angle is ∼50°, with a ∼30% chance of a retrograde configuration. Transit observations of the innermost planet—55 Cnc e—may be used to verify these findings via the Rossiter-McLaughlin effect. 55 Cancri may thus represent a new class of planetary systems with well-ordered, coplanar orbits that are inclined with respect to the stellar equator.

  17. Selection of coplanar or noncoplanar beams using three-dimensional optimization based on maximum beam separation and minimized nontarget irradiation

    International Nuclear Information System (INIS)

    Das, Shiva K.; Marks, Lawrence B.

    1997-01-01

    Purpose: The design of an appropriate set of multiple fixed fields to achieve a steep dose gradient at the tumor edge, with minimal normal tissue exposure, is a very difficult problem, since a virtually infinite number of possible beam orientations exists. In practice we have selected beams in an iterative and often time-consuming process. This work proposes an optimization method, based on geometric and dose elements, to effectively arrive at a set of beam orientations. Methods and Materials: Beams are selected by minimizing a goal function including an angle function (beam separation for steep dose gradient at target edge) and a length function (related to normal tissue dose volume histogram). The relative importance of these two factors may be adjusted depending on the clinic situation. The model is flexible and can include case specific practical anatomic and physical considerations. Results: In extremely simple situations, the goal function yields results consistent with well-known analytical solutions. When applied to more complex clinical situations, it provides clinically reasonable solutions similar to those empirically developed by the clinician. The optimization process takes approximately 25 min on a UNIX workstation. Conclusion: The optimization scheme provides a practical means for rapidly designing multiple field coplanar or noncoplanar treatments. It overcomes limitations in human three-dimensional visualization such as trying to visualize beam directions and keeping track of the hinge angle between beams while accounting for anatomic/machine constraints. In practice, it has been used as a starting point for physicians to make modifications, based on their clinical judgment

  18. SU-F-T-649: Dosimetric Evaluation of Non-Coplanar Arc Therapy Using a Novel Rotating Gamma Ray System

    Energy Technology Data Exchange (ETDEWEB)

    Eldib, A; Chibani, O; Jin, L; Fan, J; Veltchev, I; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States); Mora, G [Universidade de Lisboa, Codex, Lisboa (Portugal); Li, J [Cyber Medical Inc, Xian, Shaanxi (China)

    2016-06-15

    Purpose: Stereotactic intra and extra-cranial body radiation therapy has evolved with advances in treatment accuracy, effective radiation dose, and parameters necessary to maximize machine capabilities. Novel gamma systems with a ring type gantry were developed having the ability to perform oblique arcs. The aim of this study is to explore the dosimetric advantages of this new system. Methods: The rotating Gamma system is named CybeRay (Cyber Medical Corp., Xian, China). It has a treatment head of 16 cobalt-60 sources focused to the isocenter, which can rotate 360° on the ring gantry and swing 35° in the superior direction. Treatment plans were generated utilizing our in-house Monte Carlo treatment planning system. A cylindrical phantom was modeled with 2mm voxel size. Dose inside the cylindrical phantom was calculated for coplanar and non-coplanar arcs. Dosimetric differences between CybeRay cobalt beams and CyberKnife 6MV beams were compared in a lung phantom and for previously treated SBRT patients. Results: The full width at half maxima of cross profiles in the S-I direction for the coplanar setup matched the cone sizes, while for the non-coplanar setup, FWHM was larger by 2mm for a 10mm cone and about 5mm for larger cones. In the coronal and sagittal view, coplanar beams showed elliptical shaped isodose lines, while non-coplanar beams showed circular isodose lines. Thus proper selection of the oblique angle and cone size can aid optimal dose matching to the target volume. Comparing a single 5mm cone from CybeRay to that from CyberKnife showed similar penumbra in a lung phantom but CybeRay had significant lower doses beyond lung tissues. Comparable treatment plans were obtained with CybeRay as that from CyberKnife.ConclusionThe noncoplanar multiple source arrangement of CybeRay will be of great clinical benefits for stereotactic intra and extra-cranial radiation therapy.

  19. A numerical study of natural hydrate formation kinetics in petroleum pipelines by the phase field method: influence of the model parameters; Estudo da cinetica de formacao de hidratos em dutos de petroleo pelo metodo do campo de fase: influencia dos parametros do modelo

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Mabelle Biancardi; Castro, Jose Adilson de; Silva, Alexandre Jose da; Ferreira, Alexandre Furtado [Universidade Federal Fluminense (UFF), Volta Redonda, RJ (Brazil). Pos-Graduacao em Engenharia Metalurgica], e-mail: mabelle@metal.eeimvr.uff.br, e-mail: adilson@metal.eeimvr.uff.br, e-mail: ajs@metal.eeimvr.uff.br, e-mail: furtado@metal.eeimvr.uff.br

    2006-07-01

    The objective of this work is to study the influence of the parameters of the phase field model field on the formation of natural hydrates. It was investigated parameters such as superficial tension, effect of the super-cooling, homogeneous and heterogeneous nucleation. The influence of these parameters was analyzed according to morphology of the interface and the rate of formation. The mathematical model to describe the evolution of the natural hydrates formation is based on the simultaneous solution of the phase and energy equations. The finite volume numerical method was used to discretize the governing differential equations. Results of the simulation indicated that the reduction of the superficial tension leads to the increase of the surface rugosity, interface thickness and instability of the interface resulting in a decrease of the rate growth. In order to investigate the nucleation effect of the natural hydrates, two conditions had been simulated a) the random distribution of nuclei: where the evolution of formed hydrates suffered coalescence and the kinetic decreased due to impingement of hydrates regions and b) Nucleation in the pipeline wall, where rough interfaces were observed. (author)

  20. Double exchange model on triangular lattice: Non-coplanar spin configuration and phase transition near quarter filling

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, G.P., E-mail: bugubird_zhang@hotmail.com [Department of Physics, Renmin University of China, Beijing 100872 (China); Zhang, Jian [3M Company, 3M Corporate Headquarters, 3M Center, St. Paul, MN 55144-1000 (United States); Zhang, Qi-Li [Data Center for High Energy Density Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Zhou, Jiang-Tao [College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); Shangguan, M.H. [Department of Physics, Renmin University of China, Beijing 100872 (China)

    2013-05-15

    Unconventional anomalous Hall effect in frustrated pyrochlore oxides is originated from spin chirality of non-coplanar localized spins, which can also be induced by the competition between ferromagnetic (FM) double exchange interaction J{sub H} and antiferromagnetic superexchange interaction J{sub AF}. Here truncated polynomial expansion method and Monte Carlo simulation are adopted to investigate the above model on two-dimensional triangular lattice. We discuss the influence of the range of FM-type spin–spin correlation and strong electron–spin correlation on the truncation error of spin–spin correlation near quarter filling. Two peaks of the probability distribution of spin–spin correlation in non-coplanar spin configuration clearly show that non-coplanar spin configuration is an intermediate phase between FM and 120° spin phase. Near quarter filling, there is a phase transition from FM into non-coplanar and further into 120° spin phase when J{sub AF} continually increases. Finally the effect of temperature on the magnetic structure is discussed.

  1. CIRCULARLY POLARIZED SLOTTED APERTURE ANTENNA WITH COPLANAR WAVEGUIDE FED FOR BROADBAND APPLICATIONS

    Directory of Open Access Journals (Sweden)

    B. T. P. MADHAV

    2016-02-01

    Full Text Available Coplanar waveguide fed circularly polarized microstrip patch antenna performance evaluation is presented in this paper. The broadband characteristics are attained by placing open end slot at the lower side of the antenna. The proposed design has the return loss of less than -10dB and VSWR<2 in the desired band of operation. A gain of 3dB to 4dB is attained in the desired band with good radiation characteristics and a suitable axial ratio of less than 3 dB is attained in the prescribed band of operation. Proposed antenna is fabricated on the FR4 substrate with dielectric constant of 4.4. Parametric analysis with change in substrate permittivity also performed and the optimized dimensions are presented in this work.

  2. Neural Models for the Broadside-Coupled V-Shaped Microshield Coplanar Waveguides

    Science.gov (United States)

    Guney, K.; Yildiz, C.; Kaya, S.; Turkmen, M.

    2006-09-01

    This article presents a new approach based on multilayered perceptron neural networks (MLPNNs) to calculate the odd-and even-mode characteristic impedances and effective permittivities of the broadside-coupled V-shaped microshield coplanar waveguides (BC-VSMCPWs). Six learning algorithms, bayesian regulation (BR), Levenberg-Marquardt (LM), quasi-Newton (QN), scaled conjugate gradient (SCG), resilient propagation (RP), and conjugate gradient of Fletcher-Powell (CGF), are used to train the MLPNNs. The neural results are in very good agreement with the results reported elsewhere. When the performances of neural models are compared with each other, the best and worst results are obtained from the MLPNNs trained by the BR and CGF algorithms, respectively.

  3. The geometry of three-dimensional measurement from paired coplanar x-ray images.

    Science.gov (United States)

    Baumrind, S; Moffitt, F H; Curry, S

    1983-10-01

    This article outlines the geometric principles which underlie the process of making craniofacial measurements in three dimensions by combining information from pairs of coplanar x-ray images. The main focus is upon the rationale of the method rather than upon the computational details. We stress particularly the importance of having available accurate measurements as to the relative positions of the x-ray tubes and the film plane. The use of control arrays of radiopaque "points" whose projected images upon the film plane allow the retrospective calculation of the spatial relationship between the x-ray tubes and the film plane is explained. Finally, the question of correcting for movement of the subject between two films of an image pair is considered briefly.

  4. On the Coplanar Integrable Case of the Twice-Averaged Hill Problem with Central Body Oblateness

    Science.gov (United States)

    Vashkov'yak, M. A.

    2018-01-01

    The twice-averaged Hill problem with the oblateness of the central planet is considered in the case where its equatorial plane coincides with the plane of its orbital motion relative to the perturbing body. A qualitative study of this so-called coplanar integrable case was begun by Y. Kozai in 1963 and continued by M.L. Lidov and M.V. Yarskaya in 1974. However, no rigorous analytical solution of the problem can be obtained due to the complexity of the integrals. In this paper we obtain some quantitative evolution characteristics and propose an approximate constructive-analytical solution of the evolution system in the form of explicit time dependences of satellite orbit elements. The methodical accuracy has been estimated for several orbits of artificial lunar satellites by comparison with the numerical solution of the evolution system.

  5. A Reconfigurable Coplanar Waveguide Bowtie Antenna Using an Integrated Ferroelectric Thin-Film Varactor

    Directory of Open Access Journals (Sweden)

    K. C. Pan

    2012-01-01

    Full Text Available A novel printed antenna with a frequency reconfigurable feed network is presented. The antenna consists of a bowtie structure patch radiating element in the inner space of an annulus that is on a nongrounded substrate with a ferroelectric (FE Barium Strontium Titanate (BST thin film. The bowtie patch is fed by a coplanar waveguide (CPW transmission line that also includes a CPW-based BST shunt varactor. Reconfiguration of the compact 8 mm × 8 mm system has been demonstrated by shifting the antenna system’s operating frequency 500 MHz in the 7–9 GHz band by applying a DC voltage bias.

  6. Planar self-aligned imprint lithography for coplanar plasmonic nanostructures fabrication

    KAUST Repository

    Wan, Weiwei

    2014-03-01

    Nanoimprint lithography (NIL) is a cost-efficient nanopatterning technology because of its promising advantages of high throughput and high resolution. However, accurate multilevel overlay capability of NIL required for integrated circuit manufacturing remains a challenge due to the high cost of achieving mechanical alignment precision. Although self-aligned imprint lithography was developed to avoid the need of alignment for the vertical layered structures, it has limited usage in the manufacture of the coplanar structures, such as integrated plasmonic devices. In this paper, we develop a new process of planar self-alignment imprint lithography (P-SAIL) to fabricate the metallic and dielectric structures on the same plane. P-SAIL transfers the multilevel imprint processes to a single-imprint process which offers higher efficiency and less cost than existing manufacturing methods. Such concept is demonstrated in an example of fabricating planar plasmonic structures consisting of different materials. © 2014 Springer-Verlag Berlin Heidelberg.

  7. Novel method to improve power handling capability for coplanar waveguide high-temperature superconducting filter

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, K; Koizumi, D; Narahashi, S [NTT DoCoMo, Inc., 3-5 Hikari-no-oka, 239-8536 Yokosuka (Japan)

    2006-06-01

    This paper proposes a novel method to improve the power handling capability of a coplanar waveguide (CPW) high-temperature superconducting (HTS) filter. The noteworthy point of the proposed method is that it is based on the concept that the power handling capability is improved by reducing the maximum current density of the filter. Numerical investigations confirm that a CPW HTS filter using 66-{omega} characteristic impedance resonators (66-{omega} CPW HTSF) reduces the maximum current density compared to that using conventional 50-{omega} resonators (50-{omega} CPW HTSF). We fabricated 5-GHz band four-pole Chevyshev CPW HTSFs based on the proposed and conventional methods. The fabricated 66-{omega} CPW HTSF exhibited the third-order intercept point (TOI) of + 61 dBm while the 50-{omega} CPW HTSF exhibited the TOI of + 54 dBm, both at 60 K. These results indicate the effectiveness of the proposed method.

  8. UHF coplanar-slot antenna for aircraft-to-satellite data communications

    Science.gov (United States)

    Myhre, R. W.

    1979-01-01

    The initiative for starting the Aircraft-to-Satellite Data Relay (ASDAR) Program came from a recognition that much of the world's weather originates in the data sparse area of the tropics which are primarily ocean. The ASDAR system consists of (1) a data acquisition and control unit to acquire, store and format these data; (2) a clock to time the data sampling and transmission periods; and (3) a transmitter and low-profile upper hemisphere coverage antenna to relay the formatted data via satellite to the National Weather Service ground stations, as shown schematically. The low-profile antenna is a conformal antenna based on the coplanar-slot approach. The antenna is circular polarized and has an on-axis gain of nearly 2.5 dB and a HPBW greater than 90 deg. The discussion covers antenna design, radiation characteristics, flight testing, and system performance.

  9. Three-dimensional x-ray stereometry from paired coplanar images: a progress report.

    Science.gov (United States)

    Baumrind, S; Moffitt, F H; Curry, S

    1983-10-01

    More than fifty years ago, Broadbent reported the development of a three-dimensional cephalometric method which complexed information from pairs of x-ray images oriented in two planes at right angles to each other. Empirical problems have prevented the routine clinical use of this "biplanar" method, notwithstanding its obvious conceptual brilliance. The present article reports on recent work toward the development of an alternative method of three-dimensional cephalometry in which the two images of each x-ray pair are positioned in the same plane rather than being at right angles to each other. It is believed that this "coplanar" method avoids many of the technical problems that have limited the use of the Broadbent method.

  10. Correlacion entre metodos de analisis de Zn disponible en cuatro ordenes de suelos de Costa Rica

    Directory of Open Access Journals (Sweden)

    Eloy Molina

    2001-01-01

    Full Text Available Se realizo una comparación entre métodos analisis del Zn disponible en 4 ordenes de sue- Analytilos de Costa Rica (Ultisoles, Vertisoles, Andisoles Inceptisoles, 25 de c/u, utilizando las siguientes soluciones extractoras: Olsen Modificado, Meh- lich 3, Morgan Modificado, DTPA y HC1. Las cantidades de Zn extrafdas dependieron de la natu- raleza qufmica de la solucion extractora. El HCl presento los contenidos mas altos de Zn en los chasuelos, excepto en Vertisoles. Las soluciones que hicontienen el agente quelante EDTA (Olsen Modi- ficado y Mehlich`3, extrajeron niveles interme- Modidios de Zn, en tanto que los metodos que contie- Den el quelato DTPA (Morgan Modificado y DT - PA, obtuvieron los valores mas bajos. Las corre- laciones de Zn extrafble entre los 5 metodos fue- signifirOD significativas en la mayona de los casos, tanto nivel de orden de suelos como en el conjunto de indivilos 100 suelos analizados. Los coeficientes de co- rrelacion mas altos, se presentaron entre Mehlich Morgan Modificado y DTPA. Las correlaciones Modifueron consistentes en los 4 ordenes, 10 que indica que estas soluciones poseen un amplio margen de adaptacion a diferentes tipos de suelo, siendo una caractenstica ventajosa para la selección de un metodo de analisis. El Olsen Modificado fue mas slighteficiente para la extraccion de Zn en suelos de pH ligeramente acido 0 neutro (Vertisoles e Inceptiso- les, que en suelos acidos (Ultisoles y Andisoles. EI HCI extrajo cantidades muy aItas de Zn que Moraparentementestan relacionadas con formas no disponibles para lag plantas. Se concluye que lag soluciones Mehlich 3, Morgan Modificado y DT - PA son semejantes en la forma de extraer Zn dispo- Dible, y podrian seT una altemativa para sustituir el metoda tradicional de Olsen Modificado utilizado en Costa Rica. Sin embargo,la eficiencia de ellas no puede seT establecida sino a traves de log estudios de correlacion contra rendimiento en invernadero y campo.

  11. Electromagnetic Modeling of Distributed-Source-Excitation of Coplanar Waveguides: Applications to Traveling-Wave Photomixers

    Science.gov (United States)

    Pasqualini, Davide; Neto, Andrea; Wyss, Rolf A.

    2001-01-01

    In this work an electromagnetic model and subsequent design is presented for a traveling-wave, coplanar waveguide (CPW) based source that will operate in the THz frequency regime. The radio frequency (RF) driving current is a result of photoexcitation of a thin GaAs membrane using two frequency-offset lasers. The GaAs film is grown by molecular-beam-epitaxy (MBE) and displays sub-ps carrier lifetimes which enable the material conductivity to be modulated at a very high rate. The RF current flows between electrodes deposited on the GaAs membrane which are biased with a DC voltage source. The electrodes form a CPW and are terminated with a double slot antenna that couples the power to a quasi-optical system. The membrane is suspended above a metallic reflector to launch all radiation in one direction. The theoretical investigation and consequent design is performed in two steps. The first step consists of a direct evaluation of the magnetic current distribution on an infinitely extended coplanar waveguide excited by an impressed electric current distributed over a finite area. The result of the analysis is the difference between the incident angle of the laser beams and the length of the excited area that maximizes the RF power coupled to the CPW. The optimal values for both parameters are found as functions of the CPW and membrane dimensions as well as the dielectric constants of the layers. In the second step, a design is presented of a double slot antenna that matches the CPW characteristic impedance and gives good overall performance. The design is presently being implemented and measurements will soon be available.

  12. Osservazioni sul principio di legalità come idea e come metodo nell’esperienza giuridica della Chiesa

    Directory of Open Access Journals (Sweden)

    Beatrice Serra

    2012-10-01

    SOMMARIO: 1. Introduzione - 2. – La struttura essenziale del concetto di legalità e la sua realizzazione radicale nel diritto della Chiesa. - 3. L’idea di legalità come “regola che sta prima” nel ius commune e la sua coesistenza con un approccio empirico, essenzialmente giurisprudenziale e dottrinale, di costruzione del diritto. Il principio di legalità come metodo di produzione del diritto nel pensiero giuridico moderno- 4. Il legame storico-concettuale fra il principio di legalità e i Codici moderni - 5. Il Codex iuris canonici del 1917 e il principio di legalità come metodo di costruzione del ius ecclesiae in funzione della certezza del diritto - 6. (segueUlteriori riflessi della prima codificazione canonica sul principio di legalità.:

  13. Analytic computation of the quantum levels of a two-dimensional hydrogenic donor in the presence of a constant magnetic field of arbitrary strength

    Energy Technology Data Exchange (ETDEWEB)

    Villalba, Victor M.; Pino, Ramiro [Instituto Venezolano de Investigaciones Cientificas, Caracas (Venezuela)

    2001-03-01

    In this article we review different techniques for computing the energy spectrum of 2 D hydrogenic donors and two-electron quantum dots in the presence of a constant, magnetic field perpendicular to the plane of the electron. We compute the 1S, 2P- and 3D- energy levels via a scaled variational mixed-bases method. We compare our results with those obtained with the shifted 1/N method. [Spanish] En el presente articulo se exhiben distintos metodos para calcular el espectro de energia de donores hidrogenicos y puntos cuanticos con dos electrones en presencia de un campo magnetico constante perpendicular al plano del electron. Se calculan los niveles de energia 1S, 2P- y 3D- con ayuda del metodo variacional de bases mixtas con escalamiento. Comparamos nuestro resultados con los obtenidos con ayuda del metodo 1/N con corrimiento.

  14. Advantages and disadvantages of using non-coplanar techniques in radiotherapy of the abdomen formed 3D; Ventajas e inconvenientes del uso de tecnicas con coplanares en radiaoterpia 3D conformada de abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Urena Llinares, A.; Castro Ramirez, I.; Iborra Oquendo, M. A; Quinones Rodriguez, L. A.; Angulo Pain, E.

    2011-07-01

    3D Radiotherapy locations abdomen, especially in pancreas and stomach cancers is often extremely difficult if we are to meet the dose constraints to organs at risk due to proximity and many of these (liver, kidneys, intestines, lungs, bone. ..). Of these, the most critical are the kidneys, which also present values of tolerance, in most cases difficult to meet. This is done in our hospital are using non-coplanar techniques performing well both as coating PTV dose to both kidneys.

  15. Fraction-variant beam orientation optimization for non-coplanar IMRT

    Science.gov (United States)

    O'Connor, Daniel; Yu, Victoria; Nguyen, Dan; Ruan, Dan; Sheng, Ke

    2018-02-01

    Conventional beam orientation optimization (BOO) algorithms for IMRT assume that the same set of beam angles is used for all treatment fractions. In this paper we present a BOO formulation based on group sparsity that simultaneously optimizes non-coplanar beam angles for all fractions, yielding a fraction-variant (FV) treatment plan. Beam angles are selected by solving a multi-fraction fluence map optimization problem involving 500-700 candidate beams per fraction, with an additional group sparsity term that encourages most candidate beams to be inactive. The optimization problem is solved using the fast iterative shrinkage-thresholding algorithm. Our FV BOO algorithm is used to create five-fraction treatment plans for digital phantom, prostate, and lung cases as well as a 30-fraction plan for a head and neck case. A homogeneous PTV dose coverage is maintained in all fractions. The treatment plans are compared with fraction-invariant plans that use a fixed set of beam angles for all fractions. The FV plans reduced OAR mean dose and D 2 values on average by 3.3% and 3.8% of the prescription dose, respectively. Notably, mean OAR dose was reduced by 14.3% of prescription dose (rectum), 11.6% (penile bulb), 10.7% (seminal vesicle), 5.5% (right femur), 3.5% (bladder), 4.0% (normal left lung), 15.5% (cochleas), and 5.2% (chiasm). D 2 was reduced by 14.9% of prescription dose (right femur), 8.2% (penile bulb), 12.7% (proximal bronchus), 4.1% (normal left lung), 15.2% (cochleas), 10.1% (orbits), 9.1% (chiasm), 8.7% (brainstem), and 7.1% (parotids). Meanwhile, PTV homogeneity defined as D 95/D 5 improved from .92 to .95 (digital phantom), from .95 to .98 (prostate case), and from .94 to .97 (lung case), and remained constant for the head and neck case. Moreover, the FV plans are dosimetrically similar to conventional plans that use twice as many beams per fraction. Thus, FV BOO offers the potential to reduce delivery time for non-coplanar IMRT.

  16. Omega-3 fatty acid oxidation products prevent vascular endothelial cell activation by coplanar polychlorinated biphenyls

    International Nuclear Information System (INIS)

    Majkova, Zuzana; Layne, Joseph; Sunkara, Manjula; Morris, Andrew J.; Toborek, Michal; Hennig, Bernhard

    2011-01-01

    Coplanar polychlorinated biphenyls (PCBs) may facilitate development of atherosclerosis by stimulating pro-inflammatory pathways in the vascular endothelium. Nutrition, including fish oil-derived long-chain omega-3 fatty acids, such as docosahexaenoic acid (DHA, 22:6ω-3), can reduce inflammation and thus the risk of atherosclerosis. We tested the hypothesis that cyclopentenone metabolites produced by oxidation of DHA can protect against PCB-induced endothelial cell dysfunction. Oxidized DHA (oxDHA) was prepared by incubation of the fatty acid with the free radical generator 2,2-azo-bis(2-amidinopropane) dihydrochloride (AAPH). Cellular pretreatment with oxDHA prevented production of superoxide induced by PCB77, and subsequent activation of nuclear factor-κB (NF-κB). A 4 /J 4 -neuroprostanes (NPs) were identified and quantitated using HPLC ESI tandem mass spectrometry. Levels of these NPs were markedly increased after DHA oxidation with AAPH. The protective actions of oxDHA were reversed by treatment with sodium borohydride (NaBH 4 ), which concurrently abrogated A 4 /J 4 -NP formation. Up-regulation of monocyte chemoattractant protein-1 (MCP-1) by PCB77 was markedly reduced by oxDHA, but not by un-oxidized DHA. These protective effects were proportional to the abundance of A 4 /J 4 NPs in the oxidized DHA sample. Treatment of cells with oxidized eicosapentaenoic acid (EPA, 20:5ω-3) also reduced MCP-1 expression, but less than oxDHA. Treatment with DHA-derived cyclopentenones also increased DNA binding of NF-E2-related factor-2 (Nrf2) and downstream expression of NAD(P)H:quinone oxidoreductase (NQO1), similarly to the Nrf-2 activator sulforaphane. Furthermore, sulforaphane prevented PCB77-induced MCP-1 expression, suggesting that activation of Nrf-2 mediates the observed protection against PCB77 toxicity. Our data implicate A 4 /J 4 -NPs as mediators of omega-3 fatty acid-mediated protection against the endothelial toxicity of coplanar PCBs.

  17. Oxidative stress and apoptosis of Carassius auratus lymphocytes induced by nonplanar (PCB153) and coplanar (PCB169) polychlorinated biphenyl congeners in vitro

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-ying; ZHANG Hang-jun; NI Wan-min

    2009-01-01

    and the coplanar congener was more cytotoxic than nonplanar congener. This study suggests that cytotoxicity mechanisms of the PCB congeners on fish lymphocytes depend on their planarity and chemical structures.

  18. Polychlorinated biphenyl residues in food and human milk: determination of co-planar and mono-ortho substituted congeners

    International Nuclear Information System (INIS)

    Boehm, V.; Schulte, E.; Thier, H.P.

    1993-01-01

    An analytical method is described for determining the residues of coplanar as well as mono-ortho substituted PCB congeners both exhibiting toxicological relevance, in foods of animal origin and in human milk. The unsophisticated procedure, convenient for routine analyses, includes the extraction of lipids, clean-up steps using liquid/liquid partition and column chromatography, fractionation of the congeners using HPLC on a special carbon column with an optimal gradient elution, and capillary column gas chromatography with electron capture or mass spectrometric detection. As preliminary results indicate, the low-chlorinated PCB technical products contribute more to the actual contamination of environment and foods than has been estimated so far. Obviously the co-planar congeners are accumulated during the food chain in a portion different from that found for the other congeners. (orig.)

  19. Advantages and disadvantages of using non-coplanar techniques in radiotherapy of the abdomen formed 3D

    International Nuclear Information System (INIS)

    Urena Llinares, A.; Castro Ramirez, I.; Iborra Oquendo, M. A; Quinones Rodriguez, L. A.; Angulo Pain, E.

    2011-01-01

    3D Radiotherapy locations abdomen, especially in pancreas and stomach cancers is often extremely difficult if we are to meet the dose constraints to organs at risk due to proximity and many of these (liver, kidneys, intestines, lungs, bone. ..). Of these, the most critical are the kidneys, which also present values of tolerance, in most cases difficult to meet. This is done in our hospital are using non-coplanar techniques performing well both as coating PTV dose to both kidneys.

  20. Design and study of a coplanar grid array CdZnTe detector for improved spatial resolution

    International Nuclear Information System (INIS)

    Ma, Yuedong; Xiao, Shali; Yang, Guoqiang; Zhang, Liuqiang

    2014-01-01

    Coplanar grid (CPG) CdZnTe detectors have been used as gamma-ray spectrometers for years. Comparing with pixelated CdZnTe detectors, CPG CdZnTe detectors have either no or poor spatial resolution, which directly limits its use in imaging applications. To address the issue, a 2×2 CPG array CdZnTe detector with dimensions of 7×7×5 mm 3 was fabricated. Each of the CPG pairs in the detector was moderately shrunk in size and precisely designed to improve the spatial resolution while maintaining good energy resolution, considering the charge loss at the surface between the strips of each CPG pairs. Preliminary measurements were demonstrated at an energy resolution of 2.7–3.9% for the four CPG pairs using 662 keV gamma rays and with a spatial resolution of 3.3 mm, which is the best spatial resolution ever achieved for CPG CdZnTe detectors. The results reveal that the CPG CdZnTe detector can also be applied to imaging applications at a substantially higher spatial resolution. - Highlights: • A novel structure of coplanar grid CdZnTe detector was designed to evaluate the possibility of applying the detector to gamma-ray imaging applications. • The best spatial resolution of coplanar grid CdZnTe detectors ever reported has been achieved, along with good spectroscopic performance. • Depth correction of the energy spectra using a new algorithm is presented

  1. Coplanarity of two-proton emissions in 400 MeV/nucleon Ne + NaF, Pb reactions

    International Nuclear Information System (INIS)

    Tanihata, Isao.

    1984-10-01

    Two-proton coincidence spectra have been measured in a wide kinematical range for 20 Ne + NaF and 20 Ne + Pb collisions at 400 MeV/nucleon. Coplanar-type correlations show different feature between Ne + NaF and Ne + Pb target reactions. A strong in-plane correlation, which correspond to quasi-elastic scatterings (QES) of nucleons, was observed in wide angular range (15 to 90 0 ) in NaF target collisions. Angular distributions of QES were reproduced reasonably well by a single nucleon-nucleon scattering model. Enhancement of the QES at momentum transfer around t = 2 - 3m/sub π/, which is predicted as an indication of pionic instability, was not observed. In Ne + Pb collisions, an azimuthally asymmetric emission of particles with respect to the beam axis were implied by the anti-coplanar correlation. A new type of coplanar correlation between the emission angle and the momentum suggests a back-to-back emission of projectile and target nucleons. 8 references, 8 figures

  2. Coplanar (e, 3e) differential cross-section of He atom

    CERN Document Server

    Choubisa, R; Sud, K K

    2003-01-01

    We present in this paper the results of our calculation of five-fold differential cross-section (FDCS) for (e, 3e) process on He atom in low momentum transfer and high electron impact energy in shake-off mechanism. The formalism has been developed in Born approximation using plane waves. Byron and Joachain as well as Le Sech and correlated BBK-type wave functions respectively for incident and scattered. bound and ejected electrons. The angular distribution of FDCS of our calculation is presented in various modes of coplanar geometry and comparison is made with the available experimental data. We observe that the present calculation is able to reproduce the trend of the experimental data. However, it differs in magnitude from the experiment. The present theory does not predict four-peak structure in summed mutual angle mode for lower excess ejected electron energies. We also discuss the importance of momentum transfer, post-collision interaction (PCI) and ion participation in the (e, 3e) process in constant th...

  3. Structures of Metalloporphyrin-Oligomer Multianions: Cofacial versus Coplanar Motifs as Resolved by Ion Mobility Spectrometry.

    Science.gov (United States)

    Brendle, Katrina; Schwarz, Ulrike; Jäger, Patrick; Weis, Patrick; Kappes, Manfred

    2016-11-03

    We have combined ion mobility mass spectrometry with quantum chemical calculations to investigate the gas-phase structures of multiply negatively charged oligomers of meso-tetra(4-sulfonatophenyl)metalloporphyrins comprising the divalent metal centers Zn II , Cu II , and Pd II . Sets of candidate structures were obtained by geometry optimizations based on calculations at both the semiempirical PM7 and density functional theory (DFT) levels. The corresponding theoretical cross sections were calculated with the projection approximation and also with the trajectory method. By comparing these collision cross sections with the respective experimental values we were able to assign oligomer structures up to the tetramer. In most cases the cross sections of the lowest energy isomers predicted by theory were found to agree with the measurements to within the experimental uncertainty (2%). Specifically, we find that for a given oligomer size the structures are independent of the metal center but depend strongly on the charge state. Oligomers in low charge states with a correspondingly larger number of sodium counterions tend to form stacked, cofacial structures reminiscent of H-aggregate motifs observed in solution. By contrast, in higher charge states, the stack opens to form coplanar structures.

  4. Coplanar Waveguide Fed Compact Wide Circular-Slotted Antenna for Wi-Fi/WiMAX Applications

    Directory of Open Access Journals (Sweden)

    M. Samsuzzaman

    2014-01-01

    Full Text Available A coplanar waveguide (CPW fed printing and wide circular slotted, dual band antenna for Wi-Fi/WiMAX applications are presented. The antenna mainly encompasses a ground with a wide circular slot in the centre, a rectangular feeding strip, and two pairs of symmetric planar inverted L (SPIL strips connecting with the slotted ground. The tuning effects of the rectangular patch, ground size, and SPIL strips to the resonance and matching condition are examined by HFSS and the prototype is fabricated and measured. The simulation and experimental results show that the antenna has an impedance bandwidth with −10 dB reflection coefficients 600 MHz (3.26–3.86 GHz, lower band and 1040 MHz (5.02–6.26 GHz, upper band, which can cover both the Wi-Fi 5.2/5.5/5.8 GHz and WiMAX 3.3/3.5/3.7/5.8 GHz bands. Moreover, a stable omnidirectional radiation pattern and average peak gain for lower band 3.23 dB and upper band 5.93 dB have been achieved, respectively.

  5. Ka-Band, MEMS Switched Line Phase Shifters Implemented in Finite Ground Coplanar Waveguide

    Science.gov (United States)

    Scardelletti, Maximilian C.; Ponchak, George E.; Varaljay, Nicholas C.

    2005-01-01

    Ka-band MEMS switched line phase shifters implemented in finite ground coplanar waveguide are described in this paper. The phase shifters are constructed of single-pole double-throw (SPDT) switches with additional reference and phase offset transmission line lengths. The one- and two-bit phase shifters are fabricated on high resistivity (HR) silicon with a dielectric constant, Epsilon(sub T) = 11.7 and a substrate thickness, t = 500microns. The switching architectures integrated within the phase shifters consist of MEMS switches that are doubly anchored cantilever beam capacitive switches with additional high inductive sections (MEMS LC device). The SPDT switch is composed of a T-junction with a MEMS LC device at each output port. The one-bit phase shifter described in this paper has an insertion loss (IL) and return loss (RL) of 0.9 dB and 30 dB while the two-bit described has an IL and RL of 1.8 dB and 30 dB respectively. The one-bit phase shifter's designed offset phase is 22.5deg and actual measured phase shift is 21.8deg. The two-bit phase shifter's designed offset phase is 22.5deg, 45deg, and 67.5deg and the actual measured phase shifts are 21.4deg, 44.2deg, and 65.8deg, respectively.

  6. Co-sputtered Mo/Re superconducting coplanar resonators compatible with carbon nanotube growth

    Energy Technology Data Exchange (ETDEWEB)

    Blien, Stefan; Stiller, Peter L.; Goetz, Karl; Vavra, Ondrej; Huber, Thomas; Mayer, Thomas; Strunk, Christoph; Huettel, Andreas K. [Institute for Experimental and Applied Physics, University of Regensburg, 93040 Regensburg (Germany)

    2016-07-01

    Carbon nanotubes are simultaneously prototypical single electron tunneling devices and nano-electromechanical resonators. In particular for ''ultraclean'' devices, where the nanotube is grown in a last fabrication step over pre-existing chip structures, highly regular quantum spectra and high mechanical quality factors emerge. Targeting optomechanical experiments, a coupling of these devices to on-chip superconducting coplanar waveguide resonators is highly desirable. The conditions for in-situ growth of carbon nanotubes over metal contacts are quite detrimental to most superconductors: the CVD growth process takes place in a hydrogen/methane atmosphere heated up to 900 {sup circle} C. We present data on transmission line resonators fabricated of a co-sputtered molybdenum rhenium alloy that withstand CVD and remain superconducting with critical temperatures up to 8K after growth. Resonant operation at cryogenic temperatures is demonstrated, and the behaviour is highly consistent with a combination of Mattis-Bardeen theory and two-level systems in the substrate.

  7. Method for the depth corrected detection of ionizing events from a co-planar grids sensor

    Science.gov (United States)

    De Geronimo, Gianluigi [Syosset, NY; Bolotnikov, Aleksey E [South Setauket, NY; Carini, Gabriella [Port Jefferson, NY

    2009-05-12

    A method for the detection of ionizing events utilizing a co-planar grids sensor comprising a semiconductor substrate, cathode electrode, collecting grid and non-collecting grid. The semiconductor substrate is sensitive to ionizing radiation. A voltage less than 0 Volts is applied to the cathode electrode. A voltage greater than the voltage applied to the cathode is applied to the non-collecting grid. A voltage greater than the voltage applied to the non-collecting grid is applied to the collecting grid. The collecting grid and the non-collecting grid are summed and subtracted creating a sum and difference respectively. The difference and sum are divided creating a ratio. A gain coefficient factor for each depth (distance between the ionizing event and the collecting grid) is determined, whereby the difference between the collecting electrode and the non-collecting electrode multiplied by the corresponding gain coefficient is the depth corrected energy of an ionizing event. Therefore, the energy of each ionizing event is the difference between the collecting grid and the non-collecting grid multiplied by the corresponding gain coefficient. The depth of the ionizing event can also be determined from the ratio.

  8. In vitro reduction of coplanar PCB congeners by ABTS oxidases from the culture of Trametes versicolor

    Energy Technology Data Exchange (ETDEWEB)

    Sonoki, S. [High-Tech Research Center, Azabu Univ., Kanagawa (Japan); Sue, T.; Hisamatsu, S. [Graduate School of Environmental Health, Azabu Univ., Kanagawa (Japan); Nagasaka, H. [Inst. of Environmental Ecology, Shin-Nippon Meteorological and Oceanographical Consultant Co., Ltd., Shizuoka (Japan)

    2004-09-15

    In recent years, the environmental contamination by the harmful polluted chemicals becomes more serious. Among them, especially, the dioxins such as coplanar PCBs (Co-PCBs) and PCDDs are hard to be decomposed due to their stability and hydrophobic nature, leading to the world-wide contamination. To clean up the polluted environment, bioremediation using a microorganism is expected to solve the environmental pollution problem because of cost-effective alternative to the more established engineering method. There are some reports on the biodegradation of dioxins using various organisms, in which basidiomycetes, so-called white-rot fungi, have been extensively studied in the process of lignin degradation. As a result unique extracellular oxidative lignindegrading enzymes, such as lignin peroxidase, manganese-dependent peroxidase and laccase were supposed to be responsible for degrading dioxins. Overall many studies on biodegradation of dioxins or other chlorinated aromatic hydrocarbons have focused on using white-rot fungi; however, few reports referred to the metabolism of these environmental pollutants in the in vitro reaction by use of lignin-degrading enzymes produced by white-rot fungi. In this study, we reported the reduction of levels of Co-PCBs in the in vitro incubation with the fractions which had the oxidase activity toward 2, 2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) in the culture fluid of white-rot fungus, Trametes versicolor.

  9. Numerical study of the influence of dielectric tube on propagation of atmospheric pressure plasma jet based on coplanar dielectric barrier discharge

    Science.gov (United States)

    Haixin, HU; Feng, HE; Ping, ZHU; Jiting, OUYANG

    2018-05-01

    A 2D fluid model was employed to simulate the influence of dielectric on the propagation of atmospheric pressure helium plasma jet based on coplanar dielectric barrier discharge (DBD). The spatio-temporal distributions of electron density, ionization rate, electrical field, spatial charge and the spatial structure were obtained for different dielectric tubes that limit the helium flow. The results show that the change of the relative permittivity of the dielectric tube where the plasma jet travels inside has no influence on the formation of DBD itself, but has great impact on the jet propagation. The velocity of the plasma jet changes drastically when the jet passes from a tube of higher permittivity to one of lower permittivity, resulting in an increase in jet length, ionization rate and electric field, as well as a change in the distribution of space charges and discharge states. The radius of the dielectric tube has a great influence on the ring-shaped or solid bullet structure. These results can well explain the behavior of the plasma jet from the dielectric tube into the ambient air and the hollow bullet in experiments.

  10. Estudio numerico y experimental del proceso de soldeo MIG sobre la aleacion 6063--T5 utilizando el metodo de Taguchi

    Science.gov (United States)

    Meseguer Valdenebro, Jose Luis

    improvement on mechanical properties in aluminum metal joint. Los procesos de soldadura por arco electrico representan unas de las tecnicas mas utilizadas en los procesos de fabricacion de componentes mecanicos en la industria moderna. Los procesos de soldeo por arco se han adaptado a las necesidades actuales, haciendose un modo de fabricacion flexible y versatil. Los resultados obtenidos numericamente en el proceso de soldadura son validados experimentalmente. Los principales metodos numericos mas empleados en la actualidad son tres, metodo por diferencias finitas, metodos por elementos finitos y metodo por volumenes finitos. El metodo numerico mas empleado para el modelado de uniones soldadas, es el metodo por elementos finitos, debido a que presenta una buena adaptacion a las condiciones geometricas y de contorno ademas de que existe una diversidad de programas comerciales que utilizan el metodo por elementos finitos como base de calculo. Este trabajo de investigacion presenta un estudio experimental de una union soldada mediante el proceso MIG de la aleacion de aluminio 6063-T5. El metodo numerico se valida experimentalmente aplicando el metodo de los elementos finitos con el programa de calculo ANSYS. Los resultados experimentales obtenidos son: las curvas de enfriamiento, el tiempo critico de enfriamiento t4/3, geometria del cordon, microdurezas obtenidas en la union soldada, zona afectada termicamente y metal base, dilucion del proceso, areas criticas intersecadas entre las curvas de enfriamiento y la curva TTP. Los resultados numericos son: las curvas del ciclo termico, que representan tanto el calentamiento hasta alcanzar la temperatura maxima y un posterior enfriamiento. Se calculan el tiempo critico de enfriamiento t4/3, el rendimiento termico y se representa la geometria del cordon obtenida experimentalmente. La zona afectada termicamente se obtiene diferenciando las zonas que se encuentran a diferentes temperaturas, las areas criticas intersecadas entre las

  11. Accuracy of cranial coplanar beam therapy using an oblique, stereoscopic x-ray image guidance system

    International Nuclear Information System (INIS)

    Vinci, Justin P.; Hogstrom, Kenneth R.; Neck, Daniel W.

    2008-01-01

    A system for measuring two-dimensional (2D) dose distributions in orthogonal anatomical planes in the cranium was developed and used to evaluate the accuracy of coplanar conformal therapy using ExacTrac image guidance. Dose distributions were measured in the axial, sagittal, and coronal planes using a CIRS (Computerized Imaging Reference Systems, Inc.) anthropomorphic head phantom with a custom internal film cassette. Sections of radiographic Kodak EDR2 film were cut, processed, and digitized using custom templates. Spatial and dosimetric accuracy and precision of the film system were assessed. BrainScan planned a coplanar-beam treatment to conformally irradiate a 2-cm-diameterx2-cm-long cylindrical planning target volume. Prior to delivery, phantom misalignments were imposed in combinations of ±8 mm offsets in each of the principal directions. ExacTrac x-ray correction was applied until the phantom was within an acceptance criteria of 1 mm/1 deg. (first two measurement sets) or 0.4 mm/0.4 deg. (last two measurement sets). Measured dose distributions from film were registered to the treatment plan dose calculations and compared. Alignment errors, displacement between midpoints of planned and measured 70% isodose contours (Δc), and positional errors of the 80% isodose line were evaluated using 49 2D film measurements (98 profiles). Comparison of common, but independent measurements of Δc showed that systematic errors in the measurement technique were 0.2 mm or less along all three anatomical axes and that random error averaged (σ±σ σ ) 0.29±0.06 mm for the acceptance criteria of 1 mm/1 deg. and 0.15±0.02 mm for the acceptance criteria of 0.4 mm/0.4 deg. . The latter was consistent with independent estimates that showed the precision of the measurement system was 0.3 mm (2σ). Values of Δc were as great as 0.9, 0.3, and 1.0 mm along the P-A, R-L, and I-S axes, respectively. Variations in Δc along the P-A axis were correlated to misalignments between laser

  12. Atlas de aves: Un metodo para documentar distribucion y seguir poblaciones

    Science.gov (United States)

    Robbins, C.S.; Dowell, B.A.; Dawson, D.K.; Alvarez-Lopez, Humberto; Kattan, Gustavo; Murcia, Carolina

    1988-01-01

    Los Atlas de Aves son proyectos nacionales o regionalies para trazar en mapas la distribucion en reproduccion de cada especie de ave. Ese procedimiento se esta usando en Europa, Australia, Nueva Zelanda, Norteamerica, y partes de Africa. El tama?o de los cuadrados varia de medio grado de latitud y Iongitud hasta 5 x 5 km. El trabajo de campo de cada proyecto exige aproxlmadamente cinco a?os, pero los aficionados pueden llevar a cabo la mayor parte del trabajo. Es posible almacenar los resultados en un computador personal. Hay muchos beneficios: (I) se presenta la distribucion corriente de las aves de la nacion, del estado, o de la Iocalidad; (2) se desarrolla nueva informacion especialmente sobre especies raras o en peligro; (3) se descubren areas que tienen una avlfauna sobresaliente o habitats raros y ayuda a su proteccion, (4) se documentan cambios de dlstribucion; (5) se pueden usar para documentar cambios de poblacion, especialmente en los tropicos donde otros metodos son mas dificiles de usar porque hay muchas especies y no hay muchos observadores calificados en la identificacion de sonidos de las aves; (6) son proyectos buenos de investigacion para estudiantes graduados; (7) los turistas y los jefes de excursiones de historia natural pueden contribuir con muchas informaciones

  13. Constrained customization of non-coplanar beam orientations in radiotherapy of brain tumours

    International Nuclear Information System (INIS)

    Rowbottom, C.G.; Oldham, M.; Webb, S.

    1999-01-01

    A methodology for the constrained customization of non-coplanar beam orientations in radiotherapy treatment planning has been developed and tested on a cohort of five patients with tumours of the brain. The methodology employed a combination of single and multibeam cost functions to produce customized beam orientations. The single-beam cost function was used to reduce the search space for the multibeam cost function, which was minimized using a fast simulated annealing algorithm. The scheme aims to produce well-spaced, customized beam orientations for each patient that produce low dose to organs at risk (OARs). The customized plans were compared with standard plans containing the number and orientation of beams chosen by a human planner. The beam orientation constraint-customized plans employed the same number of treatment beams as the standard plan but with beam orientations chosen by the constrained-customization scheme. Improvements from beam orientation constraint-customization were studied in isolation by customizing the beam weights of both plans using a dose-based downhill simplex algorithm. The results show that beam orientation constraint-customization reduced the maximum dose to the orbits by an average of 18.8 (±3.8, 1SD)% and to the optic nerves by 11.4 (±4.8, 1SD)% with no degradation of the planning target volume (PTV) dose distribution. The mean doses, averaged over the patient cohort, were reduced by 4.2 (±1.1, 1SD)% and 12.4 (±3.1 1SD)% for the orbits and optic nerves respectively. In conclusion, the beam orientation constraint-customization can reduce the dose to OARs, for few-beam treatment plans, when compared with standard treatment plans developed by a human planner. (author)

  14. Radical production efficiency and electrical characteristics of a coplanar barrier discharge built by multilayer ceramic technology

    International Nuclear Information System (INIS)

    Jõgi, Indrek; Erme, Kalev; Levoll, Erik; Stamate, Eugen

    2017-01-01

    The present study investigated the electrical characteristics and radical production efficiency of a coplanar barrier discharge (CBD) device manufactured by Kyocera by multilayer ceramic technology. The device consisted of a number of linear electrodes with electrode and gap widths of 0.75 mm, immersed into a ceramic dielectric barrier. A closed flow-through system necessary for the measurements was prepared by placing a quartz plate at a height of 3 mm from the ceramic barrier. The production of nitrogen radicals was determined from the removal of a trace amount of NO in pure N 2 gas, while the production of oxygen radicals was determined by ozone production in pure O 2 or synthetic air. The production efficiency of N and O radicals and NO oxidation in synthetic air was comparable with the efficiency of a volume barrier discharge device. The power density per unit of surface area of the CBD device was more than two times larger than that of a similar volume barrier discharge setup, which makes the CBD device a compact alternative for gas treatment. The production of ozone and different nitrogen oxides was also evaluated for the open system of the CBD which is usable for surface treatment. The ozone concentration of this system was nearly independent from the input power, while the concentration of nitrogen oxides increased with input power. The open system of the CBD was additionally tested for the treatment of a silicon surface. An increase of applied power decreased the time required to reduce the water contact angle below 10 degrees but also started to have an impact on the surface roughness. (paper)

  15. Kidney-Sparing Methods for Extended-Field Intensity-Modulated Radiotherapy (EF-IMRT) in Cervical Carcinoma Treatment.

    Science.gov (United States)

    Kunogi, Hiroaki; Yamaguchi, Nanae; Terao, Yasuhisa; Sasai, Keisuke

    2016-01-01

    Coplanar extended-field intensity-modulated radiation therapy (EF-IMRT) targeting the whole-pelvic and para-aortic lymph nodes in patients with advanced cervical cancer results in impaired creatinine clearance. An improvement in renal function cannot be expected unless low-dose (approximately 10 Gy) kidney exposure is reduced. The dosimetric method should be considered during EF-IMRT planning to further reduce low-dose exposure to the kidneys. To assess the usefulness of non-coplanar EF-IMRT with kidney-avoiding beams to spare the kidneys during cervical carcinoma treatment in dosimetric analysis between non-coplanar and coplanar EF-IMRT, we compared the doses of the target organ and organs at risk, including the kidney, in 10 consecutive patients. To estimate the influence of EFRT on renal dysfunction, creatinine clearance values after treatment were also examined in 18 consecutive patients. Of these 18 patients, 10 patients who were included in the dosimetric analysis underwent extended field radiation therapy (EFRT) with concurrent chemotherapy, and eight patients underwent whole-pelvis radiation therapy with concurrent chemotherapy to treat cervical carcinoma between April 2012 and March 2015 at our institution. In the dosimetric analysis, non-coplanar EF-IMRT was effective at reducing low-dose (approximately 10 Gy) exposure to the kidneys, thus maintaining target coverage and sparing other organs at risk, such as the small bowel, rectum, and bladder, compared with coplanar EF-IMRT. Renal function in all 10 patients who underwent EFRT, including coplanar EF-IMRT (with kidney irradiation), was low after treatment, and differed significantly from that of the eight patients who underwent WPRT (no kidney irradiation) 6 months after the first day of treatment (P = 0.005). In conclusion, non-coplanar EF-IMRT should be considered in patients with advanced cervical cancer, particularly in patients with a long life expectancy or with pre-existing renal dysfunction.

  16. Subsurface microbial ecology. Epi fluorescence direct counts; Ecologia microbica del sottosuolo: metodo di conta diretta in epifluorescenza

    Energy Technology Data Exchange (ETDEWEB)

    Barra Caracciolo, A.; Silvestri, C.; Creo, C.; Izzo, G. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

    1998-07-01

    To the aim of recognize the importance of microorganisms in affecting or even determining the fate of xenobiotics in the subsurface environment evaluating bacteria concentration in a subsurface ecosystem, the report discusses a soil sample treatment method which has been developed for epi fluorescence direct counting with DAPI. [Italian] Lo studio discute un metodo di trattamento del campione per la conta diretta in epifluorescenza con un marcatore selettivo per il DNA, il DAPI, al fine di quantificare la concentrazione batterica del sottosuolo e studiare il ruolo dei microrganismi nella biodegradazione delle molecole esogene, ancora poco indagato.

  17. SU-F-T-352: Development of a Knowledge Based Automatic Lung IMRT Planning Algorithm with Non-Coplanar Beams

    International Nuclear Information System (INIS)

    Zhu, W; Wu, Q; Yuan, L

    2016-01-01

    Purpose: To improve the robustness of a knowledge based automatic lung IMRT planning method and to further validate the reliability of this algorithm by utilizing for the planning of clinical cases with non-coplanar beams. Methods: A lung IMRT planning method which automatically determines both plan optimization objectives and beam configurations with non-coplanar beams has been reported previously. A beam efficiency index map is constructed to guide beam angle selection in this algorithm. This index takes into account both the dose contributions from individual beams and the combined effect of multiple beams which is represented by a beam separation score. We studied the effect of this beam separation score on plan quality and determined the optimal weight for this score.14 clinical plans were re-planned with the knowledge-based algorithm. Significant dosimetric metrics for the PTV and OARs in the automatic plans are compared with those in the clinical plans by the two-sample t-test. In addition, a composite dosimetric quality index was defined to obtain the relationship between the plan quality and the beam separation score. Results: On average, we observed more than 15% reduction on conformity index and homogeneity index for PTV and V_4_0, V_6_0 for heart while an 8% and 3% increase on V_5, V_2_0 for lungs, respectively. The variation curve of the composite index as a function of angle spread score shows that 0.6 is the best value for the weight of the beam separation score. Conclusion: Optimal value for beam angle spread score in automatic lung IMRT planning is obtained. With this value, model can result in statistically the “best” achievable plans. This method can potentially improve the quality and planning efficiency for IMRT plans with no-coplanar angles.

  18. Spatial trends of co-planar contaminants in lobster digestive gland from the Gulf of St. Lawrence

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, W.L.; Arsenault, J.T.; Comeau, M. [Department of Fisheries and Oceans, Moncton, NB (Canada)

    1997-05-01

    A study on spatial trends of contaminants in Canadian marine biota was conducted between 1993 and 1995. Lobster digestive glands were sampled from eight locations on the Gulf of St. Lawrence near New Brunswick and Nova Scotia. A total of 15 gland samples were analysed for dioxin, furan and co-planar PCB congeners. The five highest concentrations measured (5.8-12 pg/g wet-weight) were from samples taken from within the barrier island of Miramichi Bay in New Brunswick. This is an area of municipal and industrial development where contamination levels in marine biota is a continuing local concern.

  19. Coplanar equal energy-sharing 64.6 eV e-He triple differential cross sections

    International Nuclear Information System (INIS)

    Bray, I.; Fursa, D. V.

    1996-11-01

    Electron impact ionization of the ground state of helium is measured and calculated for the case of 64.6 eV incident electrons with coplanar outgoing 20 eV electrons. Various geometries are considered: symmetric, fixed θ A and fixed θ B - θ A . The method of calculation is the convergent close-coupling theory. This theory is able to reproduce the angular profiles in essentially all of these geometries, yet it yields a constant factor of approximately two lower cross sections than experiment. 14 refs., 4 figs

  20. Exposure to coplanar PCBs induces endothelial cell inflammation through epigenetic regulation of NF-κB subunit p65

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dandan; Perkins, Jordan T. [Superfund Research Center, University of Kentucky, Lexington, KY 40536 (United States); Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40536 (United States); Petriello, Michael C. [Superfund Research Center, University of Kentucky, Lexington, KY 40536 (United States); Graduate Center for Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Hennig, Bernhard, E-mail: bhennig@uky.edu [Superfund Research Center, University of Kentucky, Lexington, KY 40536 (United States); Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40536 (United States)

    2015-12-15

    Epigenetic modifications of DNA and histones alter cellular phenotypes without changing genetic codes. Alterations of epigenetic marks can be induced by exposure to environmental pollutants and may contribute to associated disease risks. Here we test the hypothesis that endothelial cell dysfunction induced by exposure to polychlorinated biphenyls (PCBs) is mediated in part though histone modifications. In this study, human vascular endothelial cells were exposed to physiologically relevant concentrations of several PCBs congeners (e.g., PCBs 77, 118, 126 and 153) followed by quantification of inflammatory gene expression and changes of histone methylation. Only exposure to coplanar PCBs 77 and 126 induced the expression of histone H3K9 trimethyl demethylase jumonji domain-containing protein 2B (JMJD2B) and nuclear factor-kappa B (NF-κB) subunit p65, activated NF-κB signaling as evidenced by nuclear translocation of p65, and up-regulated p65 target inflammatory genes, such as interleukin (IL)-6, C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and IL-1α/β. The increased accumulation of JMJD2B in the p65 promoter led to a depletion of H3K9me3 repression mark, which accounts for the observed up-regulation of p65 and associated inflammatory genes. JMJD2B gene knockdown confirmed a critical role for this histone demethylase in mediating PCB-induced inflammation of the vascular endothelium. Finally, it was determined, via chemical inhibition, that PCB-induced up-regulation of JMJD2B was estrogen receptor-alpha (ER-α) dependent. These data suggest that coplanar PCBs may exert endothelial cell toxicity through changes in histone modifications. - Highlights: • Coplanar PCBs significantly induced histone demethylase JMJD2B expression. • Coplanar PCBs activated NF-κB through p65 up-regulation and nuclear translocation. • Histone H3K4 and K9 modifications were mediated by ER-α/JMJD2B/MLL2 complex.

  1. Milk transfer and neonatal uptake of coplanar polychlorinated biphenyl (PCB) congeners in mice

    Energy Technology Data Exchange (ETDEWEB)

    Sinjari, T. [Uppsala Univ., Dept. of Pharmaceutical Biosciences, Div. of Toxicology, Uppsala (Sweden); Klasson-Wehler, W. [Stockholm Univ., Wallenberg Lb., Environmental Chemistry, Stockholm (Sweden); Oskarsson, A. [Swedish Univ. of Agricultural Science, Dept. of Food Hygiene, Uppsala (Sweden); Darnerud, P.O. [National Food Administration, Toxicology Div., uppsala (Sweden)

    1996-03-01

    The selective accumulation of 3,3`4,3`-tetrachlorobiphenyl metabolites in late gestational fetal blood and soft tissues in mice as a result of administration of different coplanar polychlorinated biphenyl (PCB) congeners, is reported elsewhere. The situation in the nursing neonate after maternal exposure to the same congeners is now studied: The {sup 14}C-labelled congeners 3,3`,4,4`-tetrachlorobiphenyl (IUPAC number CB-77), 3,3`,4,4`,5-pentachlorobiphenyl (IUPAC number CB-126), 3,3`4,4`5,5`-hexachlorobiphenyl (IUPAC number CB-169) (all three non-ortho congeners) and 2,3,3`,4,4`-pentachlorobiphenyl (IUPAC number CB-105) (mono-ortho congener) were injected intravenously in lactating mice at day 11 post partum. One day and four days later, milk and neonatal/maternal tissues and plasma radioactivity was monitored by liquid scintillation counting (dose: 2.0 {mu}mol (20-50 {mu}Ci)/kg body weight). In milk, CB-126, -169 and -105 showed higher levels (1450-2520 pmol/ml; one day after administration) than did CB-77 (580 pmol/ml), and in neonates, the relative whole-body levels of radioactivity were related to the levels seen in milk (probably the consequences of their metabolic persistence). The comparably high {sup 14}C-concentration found in neonatal liver (about 15,000 pmol/kg) after CB-126 administration and in plasma (880 pmol/ml) after CB-77 administration could be explained by binding to specific proteins. In general, neonatal mice had two to seven times higher plasma levels than those of their mothers. These results indicate that CB-126, -169 and -105 are transferred via milk to neonates in considerable quantity and are deposited in neonatal liver, whereas CB-77 is transferred in a comparably lower amount and accumulated in neonatal plasma. The lower {sup 14}C-levels in the NMRI mothers and offspring (about half of C57BL values in maternal and neonatal plasma), could possibly be explained by a differentiated metabolism of CB-77 in these two strains.

  2. Deep Ultraviolet Copper(I) Thiocyanate (CuSCN) Photodetectors Based on Coplanar Nanogap Electrodes Fabricated via Adhesion Lithography

    KAUST Repository

    Wyatt-Moon, Gwenhivir

    2017-11-28

    Adhesion lithography (a-Lith) is a versatile fabrication technique used to produce asymmetric coplanar electrodes separated by a <15 nm nanogap. Here, we use a-Lith to fabricate deep ultraviolet (DUV) photodetectors by combining coplanar asymmetric nanogap electrode architectures (Au/Al) with solution-processable wide-band-gap (3.5–3.9 eV) p-type semiconductor copper(I) thiocyanate (CuSCN). Because of the device’s unique architecture, the detectors exhibit high responsivity (≈79 A W–1) and photosensitivity (≈720) when illuminated with a DUV-range (λpeak = 280 nm) light-emitting diode at 220 μW cm–2. Interestingly, the photosensitivity of the photodetectors remains fairly high (≈7) even at illuminating intensities down to 0.2 μW cm–2. The scalability of the a-Lith process combined with the unique properties of CuSCN paves the way to new forms of inexpensive, yet high-performance, photodetectors that can be manufactured on arbitrary substrate materials including plastic.

  3. Rectangular waveguide-to-coplanar waveguide transitions at U-band using e-plane probe and wire bonding

    DEFF Research Database (Denmark)

    Dong, Yunfeng; Johansen, Tom Keinicke; Zhurbenko, Vitaliy

    2016-01-01

    This paper presents rectangular waveguide-to-coplanar waveguide (CPW) transitions at U-band (40–60 GHz) using E-plane probe and wire bonding. The designs of CPWs based on quartz substrate with and without aluminum cover are explained. The single and double layer rectangular waveguide-to-CPW trans......This paper presents rectangular waveguide-to-coplanar waveguide (CPW) transitions at U-band (40–60 GHz) using E-plane probe and wire bonding. The designs of CPWs based on quartz substrate with and without aluminum cover are explained. The single and double layer rectangular waveguide......-to-CPW transitions using E-plane probe and wire bonding are designed. The proposed rectangular waveguide-to-CPW transition using wire bonding can provide 10 GHz bandwidth at U-band and does not require extra CPWs or connections between CPWs and chips. A single layer rectangular waveguide-to-CPW transition using E......-plane probe with aluminum package has been fabricated and measured to validate the proposed transitions. To the authors' best knowledge, this is the first time that a wire bonding is used as a probe for rectangular waveguide-to-CPW transition at U-band....

  4. Structural stability of coplanar 1T-2H superlattice MoS2 under high energy electron beam

    Science.gov (United States)

    Reshmi, S.; Akshaya, M. V.; Satpati, Biswarup; Basu, Palash Kumar; Bhattacharjee, K.

    2018-05-01

    Coplanar heterojunctions composed of van der Waals layered materials with different structural polymorphs have drawn immense interest recently due to low contact resistance and high carrier injection rate owing to low Schottky barrier height. Present research has largely focused on efficient exfoliation of these layered materials and their restacking to achieve better performances. We present here a microwave assisted easy, fast and efficient route to induce high concentration of metallic 1T phase in the original 2H matrix of exfoliated MoS2 layers and thus facilitating the formation of a 1T-2H coplanar superlattice phase. High resolution transmission electron microscopy (HRTEM) investigations reveal formation of highly crystalline 1T-2H hybridized structure with sharp interface and disclose the evidence of surface ripplocations within the same exfoliated layer of MoS2. In this work, the structural stability of 1T-2H superlattice phase during HRTEM measurements under an electron beam of energy 300 keV is reported. This structural stability could be either associated to the change in electronic configuration due to induction of the restacked hybridized phase with 1T- and 2H-regions or to the formation of the surface ripplocations. Surface ripplocations can act as an additional source of scattering centers to the electron beam and also it is possible that a pulse train of propagating ripplocations can sweep out the defects via interaction from specific areas of MoS2 sheets.

  5. Deep Ultraviolet Copper(I) Thiocyanate (CuSCN) Photodetectors Based on Coplanar Nanogap Electrodes Fabricated via Adhesion Lithography

    KAUST Repository

    Wyatt-Moon, Gwenhivir; Georgiadou, Dimitra G; Semple, James; Anthopoulos, Thomas D.

    2017-01-01

    Adhesion lithography (a-Lith) is a versatile fabrication technique used to produce asymmetric coplanar electrodes separated by a <15 nm nanogap. Here, we use a-Lith to fabricate deep ultraviolet (DUV) photodetectors by combining coplanar asymmetric nanogap electrode architectures (Au/Al) with solution-processable wide-band-gap (3.5–3.9 eV) p-type semiconductor copper(I) thiocyanate (CuSCN). Because of the device’s unique architecture, the detectors exhibit high responsivity (≈79 A W–1) and photosensitivity (≈720) when illuminated with a DUV-range (λpeak = 280 nm) light-emitting diode at 220 μW cm–2. Interestingly, the photosensitivity of the photodetectors remains fairly high (≈7) even at illuminating intensities down to 0.2 μW cm–2. The scalability of the a-Lith process combined with the unique properties of CuSCN paves the way to new forms of inexpensive, yet high-performance, photodetectors that can be manufactured on arbitrary substrate materials including plastic.

  6. fields

    Directory of Open Access Journals (Sweden)

    Brad J. Arnold

    2014-07-01

    Full Text Available Surface irrigation, such as flood or furrow, is the predominant form of irrigation in California for agronomic crops. Compared to other irrigation methods, however, it is inefficient in terms of water use; large quantities of water, instead of being used for crop production, are lost to excess deep percolation and tail runoff. In surface-irrigated fields, irrigators commonly cut off the inflow of water when the water advance reaches a familiar or convenient location downfield, but this experience-based strategy has not been very successful in reducing the tail runoff water. Our study compared conventional cutoff practices to a retroactively applied model-based cutoff method in four commercially producing alfalfa fields in Northern California, and evaluated the model using a simple sensor system for practical application in typical alfalfa fields. These field tests illustrated that the model can be used to reduce tail runoff in typical surface-irrigated fields, and using it with a wireless sensor system saves time and labor as well as water.

  7. iCycle: Integrated, multicriterial beam angle, and profile optimization for generation of coplanar and noncoplanar IMRT plans

    International Nuclear Information System (INIS)

    Breedveld, Sebastiaan; Storchi, Pascal R. M.; Voet, Peter W. J.; Heijmen, Ben J. M.

    2012-01-01

    Purpose: To introduce iCycle, a novel algorithm for integrated, multicriterial optimization of beam angles, and intensity modulated radiotherapy (IMRT) profiles. Methods: A multicriterial plan optimization with iCycle is based on a prescription called wish-list, containing hard constraints and objectives with ascribed priorities. Priorities are ordinal parameters used for relative importance ranking of the objectives. The higher an objective priority is, the higher the probability that the corresponding objective will be met. Beam directions are selected from an input set of candidate directions. Input sets can be restricted, e.g., to allow only generation of coplanar plans, or to avoid collisions between patient/couch and the gantry in a noncoplanar setup. Obtaining clinically feasible calculation times was an important design criterium for development of iCycle. This could be realized by sequentially adding beams to the treatment plan in an iterative procedure. Each iteration loop starts with selection of the optimal direction to be added. Then, a Pareto-optimal IMRT plan is generated for the (fixed) beam setup that includes all so far selected directions, using a previously published algorithm for multicriterial optimization of fluence profiles for a fixed beam arrangement Breedveld et al.[Phys. Med. Biol. 54, 7199-7209 (2009)]. To select the next direction, each not yet selected candidate direction is temporarily added to the plan and an optimization problem, derived from the Lagrangian obtained from the just performed optimization for establishing the Pareto-optimal plan, is solved. For each patient, a single one-beam, two-beam, three-beam, etc. Pareto-optimal plan is generated until addition of beams does no longer result in significant plan quality improvement. Plan generation with iCycle is fully automated. Results: Performance and characteristics of iCycle are demonstrated by generating plans for a maxillary sinus case, a cervical cancer patient, and a

  8. Evolution from the coplanar to the perpendicular plane geometry of helium (e,2e) differential cross sections symmetric in scattering angle and energy

    International Nuclear Information System (INIS)

    Murray, A.J.; Read, F.H.

    1993-01-01

    Experimentally determined differential cross sections are presented for the (e,2e) process in helium, in which the two outgoing electrons have the same energy and the same scattering angle with respect to the incident beam. At four incident energies from 20 to 50 eV above the ionization threshold the detection plane defined by the outgoing electrons was varied from being coplanar with the incident beam to being perpendicular to the beam. The differential cross section evolves from a two-peak structure in coplanar geometry to a three-peak structure in the perpendicular plane. At the lowest energy the forward-scattering coplanar peak is smaller than the backscatter peak, in contrast to the results at higher energies. A deep minimum is seen at an intermediate plane angle of 67.5 degree, this minimum being deepest at 40 eV above the ionization threshold. The results are normalized to an absolute scale using previous coplanar measurements as discussed in the text. The spectrometer used to collect these results is fully computer controlled and real-time computer optimized

  9. Plasma treatment of detonation and HPHT nanodiamonds in diffuse coplanar surface barrier discharge in H.sub.2./sub./N.sub.2./sub. flow

    Czech Academy of Sciences Publication Activity Database

    Jirásek, Vít; Čech, J.; Kozak, Halyna; Artemenko, Anna; Černák, M.; Kromka, Alexander

    2016-01-01

    Roč. 213, č. 10 (2016), s. 2680-2686 ISSN 1862-6300 R&D Projects: GA ČR(CZ) GA14-04790S Institutional support: RVO:68378271 Keywords : amination * diamond * diffuse coplanar surface barrier discharge * nanomaterials * surface functionalization Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.775, year: 2016

  10. Coplanar asymmetric angles and symmetric energy sharing triple differential cross sections for 200 eV electron-impact ionization of Ar (3p)

    International Nuclear Information System (INIS)

    Ozer, Zehra N; Varol, Onur; Yavuz, Murat; Dogan, Mevlut; Amami, Sadek; Madison, Don

    2015-01-01

    We have measured triple differential cross sections (TDCSs) for electron-impact ionization of the 3p shell of Ar at 200 eV incident electron energy. The experiments have been performed in coplanar asymmetric energy sharing geometry. The experimental results are compared with the theoretical models of three body distorted wave (3DW) and distorted wave Born approximation (DWBA). (paper)

  11. Evaluation of electromechanical coupling parameters of piezoelectric materials by using piezoelectric cantilever with coplanar electrode structure in quasi-stasis.

    Science.gov (United States)

    Zheng, Xuejun; Zhu, Yuankun; Liu, Xun; Liu, Jing; Zhang, Yong; Chen, Jianguo

    2014-02-01

    Based on Timoshenko beam theory, a principle model is proposed to establish the relationship between electric charge and excitation acceleration, and in quasi-stasis we apply the direct piezoelectric effect of multilayer cantilever with coplanar electrode structure to evaluate the piezoelectric strain coefficient d15 and electromechanical coupling coefficient k15. They are measured as 678 pC/N and 0.74 for the commercial piezoelectric ceramic lead zirconate titanate (PZT-51) bulk specimen and 656 pC/N and 0.63 for the lead magnesium niobate (PMN) bulk specimen, and they are in agreement with the calibration and simulation values. The maximum of relative errors is less than 4.2%, so the proposed method is reliable and convenient.

  12. Up-regulation of endothelial monocyte chemoattractant protein-1 by coplanar PCB77 is caveolin-1-dependent

    International Nuclear Information System (INIS)

    Majkova, Zuzana; Smart, Eric; Toborek, Michal; Hennig, Bernhard

    2009-01-01

    Atherosclerosis, the primary cause of heart disease and stroke is initiated in the vascular endothelium, and risk factors for its development include environmental exposure to persistent organic pollutants. Caveolae are membrane microdomains involved in regulation of many signaling pathways, and in particular in endothelial cells. We tested the hypothesis that intact caveolae are required for coplanar PCB77-induced up-regulation of monocyte chemoattractant protein-1 (MCP-1), an endothelium-derived chemokine that attracts monocytes into sub-endothelial space in early stages of the atherosclerosis development. Atherosclerosis-prone LDL-R -/- mice (control) or caveolin-1 -/- /LDL-R -/- mice were treated with PCB77. PCB77 induced aortic mRNA expression and plasma protein levels of MCP-1 in control, but not caveolin-1 -/- /LDL-R -/- mice. To study the mechanism of this effect, primary endothelial cells were used. PCB77 increased MCP-1 levels in endothelial cells in a time- and concentration-dependent manner. This effect was abolished by caveolin-1 silencing using siRNA. Also, MCP-1 up-regulation by PCB77 was prevented by inhibiting p38 and c-Jun N-terminal kinase (JNK), but not ERK1/2, suggesting regulatory functions via p38 and JNK MAPK pathways. Finally, pre-treatment of endothelial cells with the aryl hydrocarbon receptor (AhR) inhibitor α-naphthoflavone (α-NF) partially blocked MCP-1 up-regulation. Thus, our data demonstrate that coplanar PCB77 can induce MCP-1 expression by endothelial cells and that this effect is mediated by AhR, as well as p 38 and JNK MAPK pathways. Intact caveolae are required for these processes both in vivo and in vitro. This further supports a key role for caveolae in vascular inflammation induced by persistent organic pollutants.

  13. Method to allow the estimation of heat transfer coefficients in solar stills; Metodo para determinar coeficientes locales de transferencia de calor en destiladores solares

    Energy Technology Data Exchange (ETDEWEB)

    Rubio Cerda, Eduardo; Porta Gandara, Miguel A [CIBNOR, Mexico D.F (Mexico); Fernandez Zayas, Jose Luis [UNAM Mexico, D.F. (Mexico)

    2000-07-01

    This work reports an experimental method that allows to estimate the heat transfer coefficients in the neighborhood of walls or flat plates subject to convective transport phenomena. This method can be applied to a great variety of thermal systems since it is based on the knowledge of the border condition for the temperature at the surface of the plate, and the temperature profile that characterize the dimensionless coefficient of heat transfer in the fluid, according to its definition given by the Nusselt number. The approach of this work are the foundations of the method and the system that has been developed to apply it, that incorporates automatic acquisition equipment for continuos monitoring of the information and elements to control the parameters of interest. In addition, the experimental cavities on which the method will be evaluated are discussed, considering two different scales, as well as experiments in cavities filled with air, and with a mixture of air and steam water, as is the case for solar distillation. [Spanish] En este trabajo se presenta un metodo que permite determinar de manera experimental coeficientes de transferencia de calor por conveccion. Este metodo puede ser aplicado a una gran variedad de sistemas termicos ya que se fundamenta en el conocimiento de la condicion de frontera para la temperatura en la superficie de la placa, y del perfil de temperaturas que caracteriza el coeficiente adimensional de transferencia de calor en el fluido, de acuerdo a la definicion de este, dada por el numero de Nusselt. El trabajo que aqui se reporta esta enfocado a la fundamentacion del metodo y al equipamiento que se ha desarrollado para instrumentarlo, que incorpora equipos automaticos de adquisicion continua de informacion y elementos de control para los parametros de interes. Se presentan ademas, las cavidades experimentales sobre las que sera evaluado el metodo, que considera dos escalas diferentes, asi como experimentos en cavidades llenas de aire

  14. Non-coplanar polychlorinated biphenyls (PCBs) are direct agonists for the human pregnane-X receptor and constitutive androstane receptor, and activate target gene expression in a tissue-specific manner

    International Nuclear Information System (INIS)

    Al-Salman, Fadheela; Plant, Nick

    2012-01-01

    The polychlorinated biphenyl group possesses high environmental persistence, leading to bioaccumulation and a number of adverse effects in mammals. Whilst coplanar PCBs elicit their toxic effects through agonism of the aryl hydrocarbon receptor; however, non-coplanar PCBs are not ligands for AhR, but may be ligands for members of the nuclear receptor family of proteins. To better understand the biological actions of non-coplanar PCBs, we have undertaken a systematic analysis of their ability to activate PXR and CAR-mediated effects. Cells were exposed to a range of non-coplanar PCBs (99, 138, 153, 180 and 194), or the coplanar PCB77: Direct activation of PXR and CAR was measured using a mammalian receptor activation assay in human liver cells, with rifampicin and CITCO used as positive controls ligands for PXR and CAR, respectively; activation of target gene expression was examined using reporter gene plasmids for CYP3A4 and MDR1 transfected into liver, intestine and lung cell lines. Several of the non-coplanar PCBs directly activated PXR and CAR, whilst the coplanar PCB77 did not. Non-coplanar PCBs were also able to activate PXR/CAR target gene expression in a substitution- and tissue-specific manner. Non-coplanar PCBs act as direct activators for the nuclear receptors PXR and CAR, and are able to elicit transcriptional activation of target genes in a substitution- and tissue-dependent manner. Chronic activation of PXR/CAR is linked to adverse effects and must be included in any risk assessment of PCBs. -- Highlights: ► Several Non-coplanar PCBs are able to directly activate both PXR and CAR in vitro. ► PCB153 is the most potent direct activator of PXR and CAR nuclear receptors. ► Non-coplanar PCB activation of CYP3A4/MDR1 reporter genes is structure-dependent. ► Non-coplanar PCB activate CYP3A4/MDR1 reporter genes in a tissue-dependent. ► PCB153 is the most potent activator of PXR/CAR target gene in all tissues.

  15. The phase accumulation and antenna near field of microscopic propagating spin wave devices

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Crosby S.; Kostylev, Mikhail, E-mail: mikhail.kostylev@uwa.edu.au; Ivanov, Eugene [School of Physics M013, The University of Western Australia, Crawley, WA 6009 (Australia); Ding, Junjia; Adeyeye, Adekunle O. [Department of Electrical and Computer Engineering, National University of Singapore, 117576 Singapore (Singapore)

    2014-01-20

    We studied phase accumulation by the highly non-reciprocal magnetostatic surface spin waves in thin Permalloy microstripes excited and received by microscopic coplanar antennae. We find that the experimentally measured characteristic length of the near field of the antenna is smaller than the total width of the coplanar. This is confirmed by our numerical simulations. Consequently, the distance over which the spin wave accumulates its phase while travelling between the input and output antennae coincides with the distance between the antennae symmetry axes with good accuracy.

  16. The phase accumulation and antenna near field of microscopic propagating spin wave devices

    International Nuclear Information System (INIS)

    Chang, Crosby S.; Kostylev, Mikhail; Ivanov, Eugene; Ding, Junjia; Adeyeye, Adekunle O.

    2014-01-01

    We studied phase accumulation by the highly non-reciprocal magnetostatic surface spin waves in thin Permalloy microstripes excited and received by microscopic coplanar antennae. We find that the experimentally measured characteristic length of the near field of the antenna is smaller than the total width of the coplanar. This is confirmed by our numerical simulations. Consequently, the distance over which the spin wave accumulates its phase while travelling between the input and output antennae coincides with the distance between the antennae symmetry axes with good accuracy

  17. Exploring the alignment of carbon nanotubes dispersed in a liquid crystal matrix using coplanar electrodes

    International Nuclear Information System (INIS)

    Volpati, D.; Massey, M. K.; Kotsialos, A.; Qaiser, F.; Pearson, C.; Tiburzi, G.; Zeze, D. A.; Petty, M. C.; Johnson, D. W.; Coleman, K. S.

    2015-01-01

    We report on the use of a liquid crystalline host medium to align single-walled carbon nanotubes in an electric field using an in-plane electrode configuration. Electron microscopy reveals that the nanotubes orient in the field with a resulting increase in the DC conductivity in the field direction. Current versus voltage measurements on the composite show a nonlinear behavior, which was modelled by using single-carrier space-charge injection. The possibility of manipulating the conductivity pathways in the same sample by applying the electrical field in different (in-plane) directions has also been demonstrated. Raman spectroscopy indicates that there is an interaction between the nanotubes and the host liquid crystal molecules that goes beyond that of simple physical mixing

  18. Microscale adaptation of the potentiometric method with ion-selective electrode for the quantification of fluoride; Adaptacion a microescala del metodo potenciometrico con electrodo ion selectivo para la cuantificacion de fluoruro

    Energy Technology Data Exchange (ETDEWEB)

    Guevara Ruiz, Paulina; Ortiz Perez, Maria Deogracias [Laboratorio de Bioquimica, Facultad de de Medicina, Universidad Autonoma de San Luis Potosi, San Luis Potosi, San Luis Potosi, (Mexico)]. E-mail: mdortiz@uaslp.mx

    2009-05-15

    Similarly to other countries, ground water from Mexico is naturally polluted by fluoride. The main effects of fluoride at typical ground water concentrations are dental fluorosis, neurological deficits and reproductive disorders. In order to verify that the fluoride concentration is within the allowed guideline in Mexico (NOM 127 and 201), it is important to monitor fluoride levels in water and commercial beverages. The aim of this work is to develop a modification of the standard potentiometric method for fluoride determination in water, in order to reduce costs and amount of potentially toxic waste substances. Both methods were validated, the standard potentiometric method with the ion selective electrode and the microscale modification proposed in this paper. The methods were compared using statistic tests and graphics, followed by the comparison of 125 samples of commercial bottled water sold in the city of San Luis Potosi. Optimal results were obtained for the validation of both methods, and the microscale modification showed statistically identical results to those obtained with the standard method in all samples of bottled water. The microscale modification is a good alternative for fluoride assessment in water and beverages, and it represents a 95 % reduction of costs and chemical waste. [Spanish] En varios paises, incluido Mexico se presenta una contaminacion natural con fluoruro en agua subterranea; los principales efectos en la salud observados en poblacion expuesta a concentraciones mayores al valor permisible (que en Mexico es de 1.5 mg/L) son la fluorosis dental y esqueletica, asi como dano reproductivo y neurologico. En varios estados de la republica Mexicana, este problema es aun desconocido, de ahi la necesidad de evaluar las concentraciones de fluoruro en agua de consumo en varias comunidades. Asi, el objetivo de este trabajo es desarrollar un metodo a microescala para la determinacion de fluoruro en agua, que al reducir la cantidad de reactivo y

  19. Torque calculation in the induction motor with the finite element method; Calculo del par en el motor de induccion con el metodo del elemento finito

    Energy Technology Data Exchange (ETDEWEB)

    Castillo Diaz, Ramon

    2002-06-15

    In this work the method of the finite element is applied to the bi-dimensional analysis of the induction motor in operation in steady state, excited by sine sources of laminar currents and sine sources of voltage. The analysis is focused mainly in the calculation of the electromagnetic torque. The topics of electromagnetic theory are covered and in an idealized model of the induction motor, analytically and numerically with the method of the finite element, in the variant method of Galerkin, the vectorial potential and the torque are calculated. The results obtained with the analytical and numerical methods are compared. Three formulations are developed to calculate the torque with the method of the finite element, using triangular elements of first order, based in the equation of force of Lorentz, the Maxwell tensor and the principle of the virtual work. Finally, a motor of induction of real characteristics is simulated, assuming it is connected to a three-phase voltage source. In this motor it is analyzed the convergence and the evolution in the results obtained of the torque with different discretions, and the torque-velocity performance curve is calculated. [Spanish] En este trabajo se aplica el metodo del elemento finito al analisis bidimensional del motor de induccion en operacion en estado estable, excitado por fuentes de corriente laminar senoidales y fuentes de voltaje senoidales. El analisis se enfoca principalmente en el calculo del par electromagnetico. Se tratan los topicos de teoria electromagnetica involucrados y en un modelo idealizado del motor de induccion, se calculan analitica y numericamente con el metodo del elemento finito, en la variante metodo de Galerkin, el potencial vectorial y el par. Se comparan resultados obtenidos con los metodos analiticos y numericos. Se desarrollan tres formulaciones para calcular el par con el metodo del elemento finito, utilizando elementos triangulares de primer orden, basadas en la ecuacion de fuerza de

  20. Broadband electron spin resonance from 500 MHz to 40 GHz using superconducting coplanar waveguides

    Science.gov (United States)

    Clauss, Conrad; Bothner, Daniel; Koelle, Dieter; Kleiner, Reinhold; Bogani, Lapo; Scheffler, Marc; Dressel, Martin

    2013-04-01

    We present non-conventional electron spin resonance (ESR) experiments based on microfabricated superconducting Nb thin film waveguides. A very broad frequency range, from 0.5 to 40 GHz, becomes accessible at low temperatures down to 1.6 K and in magnetic fields up to 1.4 T. This allows for an accurate inspection of the ESR absorption position in the frequency domain, in contrast to the more common observation as a function of magnetic field. We demonstrate the applicability of frequency-swept ESR on Cr3+ atoms in ruby as well as on organic radicals of the nitronyl-nitroxide family. Measurements between 1.6 and 30 K reveal a small frequency shift of the ESR and a resonance broadening below the critical temperature of Nb, which we both attribute to a modification of the magnetic field configuration due to the appearance of shielding supercurrents in the waveguide.

  1. TU-CD-304-05: 4Ï€ Non-Coplanar Radiotherapy: From Mathematical Modeling to Clinical Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, V; Nguyen, D; Tran, A; Ruan, D; Cao, M; Kaprealian, T; Kupelian, P; Low, D; Sheng, K [Department of Radiation Oncology, UCLA, Los Angeles, CA (United States)

    2015-06-15

    Purpose: To develop and clinically implement 4π radiotherapy, an inverse optimization platform that maximally utilizes non-coplanar intensity modulated radiotherapy (IMRT) beams to significantly improve critical organ sparing. Methods: A 3D scanner was used to digitize the human and phantom subject surfaces, which were positioned in the computer assisted design (CAD) model of a TrueBeam machine to create a virtual geometrical model, based on which, the feasible beam space was calculated for different tumor locations. Beamlets were computed for all feasible beams using convolution/superposition. A column generation algorithm was employed to optimize patient specific beam orientations and fluence maps. Optimal routing through all selected beams were calculated by a level set method. The resultant plans were converted to XML files and delivered to phantoms in the TrueBeam developer mode. Finally, 4π plans were recomputed in Eclipse and manually delivered to recurrent GBM patients. Results: Compared to IMRT utilizing manually selected beams and volumetric modulated arc therapy plans, markedly improved dosimetry was observed using 4π for the brain, head and neck, liver, lung, and prostate patients. The improvements were due to significantly improved conformality and reduced high dose spillage to organs mediolateral to the PTV. The virtual geometrical model was experimentally validated. Safety margins with 99.9% confidence in collision avoidance were included to the model based model accuracy estimates determined via 300 physical machine to phantom distance measurements. Automated delivery in the developer mode was completed in 10 minutes and collision free. Manual 4 π treatment on the GBM cases resulted in significant brainstem sparing and took 35–45 minutes including multiple images, which showed submillimeter cranial intrafractional motion. Conclusion: The mathematical modeling utilized in 4π is accurate to create and guide highly complex non-coplanar IMRT

  2. A Complete First-Order Analytical Solution for Optimal Low-Thrust Limited-Power Transfers Between Coplanar Orbits with Small Eccentricities

    Science.gov (United States)

    Da Silva Fernandes, Sandro; Das Chagas Carvalho, Francisco; Vilhena de Moraes, Rodolpho

    The purpose of this work is to present a complete first order analytical solution, which includes short periodic terms, for the problem of optimal low-thrust limited power trajectories with large amplitude transfers (no rendezvous) between coplanar orbits with small eccentricities in Newtonian central gravity field. The study of these transfers is particularly interesting because the orbits found in practice often have a small eccentricity and the problem of transferring a vehicle from a low earth orbit to a high earth orbit is frequently found. Besides, the analysis has been motivated by the renewed interest in the use of low-thrust propulsion systems in space missions verified in the last two decades. Several researchers have obtained numerical and sometimes analytical solutions for a number of specific initial orbits and specific thrust profiles. Averaging methods are also used in such researches. Firstly, the optimization problem associated to the space transfer problem is formulated as a Mayer problem of optimal control with Cartesian elements - position and velocity vectors - as state variables. After applying the Pontryagin Maximum Principle, successive Mathieu transformations are performed and suitable sets of orbital elements are introduced. The short periodic terms are eliminated from the maximum Hamiltonian function through an infinitesimal canonical transformation built through Hori method - a perturbation canonical method based on Lie series. The new Hamiltonian function, which results from the infinitesimal canonical transformation, describes the extremal trajectories for long duration maneuvers. Closed-form analytical solutions are obtained for the new canonical system by solving the Hamilton-Jacobi equation through the separation of variables technique. By applying the transformation equations of the algorithm of Hori method, a first order analytical solution for the problem is obtained in non-singular orbital elements. For long duration maneuvers

  3. Analysis of a flip-chip bonded tunable high-temperature superconducting coplanar waveguide resonator using the conformal mapping technique

    CERN Document Server

    Misra, M; Murakami, H; Tonouchi, M

    2003-01-01

    We have studied the tuning properties of a high-temperature superconducting (HTS) half-wavelength coplanar waveguide (CPW) resonator operating at 5 GHz. The tuning schemes are based on flip-chip bonding of an electrically tunable ferroelectric (FE) thin film and a mechanically movable low-loss single crystal on top of the resonator. Using the conformal mapping method, closed-form analytical expressions have been derived for a flip-chip bonded conductor-backed and top-shielded CPW transmission line. The obtained expressions are used to analyse the volume effect of the FE thin film and the gap between the flip-chip and the CPW resonator on the tuning properties of the device. It has been found that large frequency modulation of the resonator produces impedance mismatch, which can considerably enhance the insertion loss of high-performance HTS microwave devices. Analysis also suggests that, for electrically tunable devices, flip-chip bonded FE thin films on HTS CPW devices provide a relatively higher performance...

  4. Improving wettability of photo-resistive film surface with plasma surface modification for coplanar copper pillar plating of IC substrates

    International Nuclear Information System (INIS)

    Xiang, Jing; Wang, Chong; Chen, Yuanming; Wang, Shouxu; Hong, Yan; Zhang, Huaiwu; Gong, Lijun; He, Wei

    2017-01-01

    Highlights: • Air atmosphere plasmacould generatehydrophilic groups of photo-resistive film. • Better wettability of photo-resistive filmled tohigher plating uniformity of copper pillars. • New flow isreduced cost, simplified process and elevated productivity. - Abstract: The wettability of the photo-resistive film (PF) surfaces undergoing different pretreatments including the O_2−CF_4 low-pressure plasma (OCLP) and air plasma (AP), is investigated by water contact angle measurement instrument (WCAMI) before the bottom-up copper pillar plating. Chemical groups analysis performed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectra (XPS) shows that after the OCLP and wash treatment, the wettability of PF surface is attenuated, because embedded fluorine and decreased oxygen content both enhance hydrophobicity. Compared with OCLP treatment, the PF surface treatment by non-toxic air plasma displays features of C−O, O−C=O, C=O and −NO_2 by AIR-FTIR and XPS, and a promoted wettability by WCAM. Under the identical electroplating condition, the surface with a better wettability allows electrolyte to spontaneously soak all the places of vias, resulting in improved copper pillar uniformity. Statistical analysis of metallographic data shows that more coplanar and flat copper pillars are achieved with the PF treatment of air plasma. Such modified copper-pillar-plating technology meets the requirement of accurate impedance, the high density interconnection for IC substrates.

  5. Improving wettability of photo-resistive film surface with plasma surface modification for coplanar copper pillar plating of IC substrates

    Science.gov (United States)

    Xiang, Jing; Wang, Chong; Chen, Yuanming; Wang, Shouxu; Hong, Yan; Zhang, Huaiwu; Gong, Lijun; He, Wei

    2017-07-01

    The wettability of the photo-resistive film (PF) surfaces undergoing different pretreatments including the O2sbnd CF4 low-pressure plasma (OCLP) and air plasma (AP), is investigated by water contact angle measurement instrument (WCAMI) before the bottom-up copper pillar plating. Chemical groups analysis performed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectra (XPS) shows that after the OCLP and wash treatment, the wettability of PF surface is attenuated, because embedded fluorine and decreased oxygen content both enhance hydrophobicity. Compared with OCLP treatment, the PF surface treatment by non-toxic air plasma displays features of Csbnd O, Osbnd Cdbnd O, Cdbnd O and sbnd NO2 by AIR-FTIR and XPS, and a promoted wettability by WCAM. Under the identical electroplating condition, the surface with a better wettability allows electrolyte to spontaneously soak all the places of vias, resulting in improved copper pillar uniformity. Statistical analysis of metallographic data shows that more coplanar and flat copper pillars are achieved with the PF treatment of air plasma. Such modified copper-pillar-plating technology meets the requirement of accurate impedance, the high density interconnection for IC substrates.

  6. True coincidence-summing corrections for the coincident γ-rays measured with coplanar grid CdZnTe detectors

    International Nuclear Information System (INIS)

    Yuecel, H.; Solmaz, A.N.; Koese, E.; Bor, D.

    2010-01-01

    In this study, true coincidence-summing (TCS) correction factors have been measured for the sources 22 Na, 60 Co, 133 Ba and 152 Eu by use of three large volume coplanar grid CdZnTe (acronym: CZT) detectors. In case of a close-in detection geometry, two different TCS calculation algorithms were used to compute the required TCS correction factors. Both of the algorithms are based on the measured total-to-peak (TTP) ratio and full-energy peak (FEP) efficiency values that were obtained using almost 'single' energy and coincidence-free nuclides. The results for TCS correction factors obtained by two different algorithms were agreeable to each other. The obtained TCS factors were ranged from about 7% to 30.5% in a 2250 mm 3 CZT detector when a close counting geometry was used. For other two detectors with a volume of 1000 and 1687.5 mm 3 , the resulted TCS correction factors were relatively smaller and varied between about 0.1% and 20% at the close counting geometry condition. Therefore, the results indicate that there is a need for the estimation of TCS corrections in CZT detectors, especially when their crystal volumes are greater than 1 cm 3 and these detectors are used in the case of a close-in detection geometry.

  7. Improving wettability of photo-resistive film surface with plasma surface modification for coplanar copper pillar plating of IC substrates

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Jing; Wang, Chong; Chen, Yuanming; Wang, Shouxu; Hong, Yan; Zhang, Huaiwu [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Gong, Lijun [Research and Development Department, Guangzhou Fastprint Circuit Tech Co., Ltd., Guangzhou 510663 (China); He, Wei, E-mail: heweiz@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Research and Development Department, Guangdong Guanghua Sci-Tech Co., Ltd., Shantou 515000 (China)

    2017-07-31

    Highlights: • Air atmosphere plasmacould generatehydrophilic groups of photo-resistive film. • Better wettability of photo-resistive filmled tohigher plating uniformity of copper pillars. • New flow isreduced cost, simplified process and elevated productivity. - Abstract: The wettability of the photo-resistive film (PF) surfaces undergoing different pretreatments including the O{sub 2}−CF{sub 4} low-pressure plasma (OCLP) and air plasma (AP), is investigated by water contact angle measurement instrument (WCAMI) before the bottom-up copper pillar plating. Chemical groups analysis performed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectra (XPS) shows that after the OCLP and wash treatment, the wettability of PF surface is attenuated, because embedded fluorine and decreased oxygen content both enhance hydrophobicity. Compared with OCLP treatment, the PF surface treatment by non-toxic air plasma displays features of C−O, O−C=O, C=O and −NO{sub 2} by AIR-FTIR and XPS, and a promoted wettability by WCAM. Under the identical electroplating condition, the surface with a better wettability allows electrolyte to spontaneously soak all the places of vias, resulting in improved copper pillar uniformity. Statistical analysis of metallographic data shows that more coplanar and flat copper pillars are achieved with the PF treatment of air plasma. Such modified copper-pillar-plating technology meets the requirement of accurate impedance, the high density interconnection for IC substrates.

  8. Discrimination of alpha particles in CdZnTe detectors with coplanar grid for the COBRA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rebber, Henning [Universitaet Hamburg, Institut fuer Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Collaboration: COBRA-Collaboration

    2016-07-01

    The aim of the COBRA experiment is the search for neutrinoless double beta decay using CdZnTe semiconductor detectors. A background rate in the order of 10{sup -3} counts per keV, kg and year is intended in order to be sensitive to a half-life larger than 10{sup 26} years. Measurements from a demonstrator setup and Monte Carlo simulations indicate that a large background component is due to alpha particles. These generate charge clouds of only few μm in diameter in the detector, leading to characteristic pulse features. Parameter-based cut criteria were developed to discriminate alpha events by means of their pulse shapes. The cuts were tested on data from alpha and beta irradiation of a (1 x 1 x 1) cm{sup 3} CdZnTe detector with coplanar grid. The pulse shapes of all event signals were read out by FADCs with a sampling rate of 100 MHz. The signals were reproduced by a detector simulation which hence was used to study the cuts for energies up to 3 MeV and different detector regions.

  9. Atomic processes in strong bichromatic elliptically polarized laser fields

    Energy Technology Data Exchange (ETDEWEB)

    Odžak, S., E-mail: senad.odzak@gmail.com; Hasović, E.; Gazibegović-Busuladžić, A.; Čerkić, A., E-mail: anercerkic@yahoo.com; Fetić, B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegovina); Kramo, A. [BHANSA, Aeronautical Meteorology Department, Kurta Schorka 36, 71000 Sarajevo (Bosnia and Herzegovina); Busuladžić, M. [Medical Faculty, University of Sarajevo, Čekaluša 90, 71000 Sarajevo (Bosnia and Herzegovina); Milošević, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegovina); Academy of Sciences and Arts of Bosnia and Herzegovina, Bistrik 7, 71000 Sarajevo (Bosnia and Herzegovina); Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany)

    2016-03-25

    Nonlinear quantum-mechanical phenomena in strong laser fields, such as high-order harmonic generation (HHG) and above-threshold ionization (ATI) are significantly modified if the applied laser field is bichromatic and/or elliptically polarized. Numerical results obtained within the strong-field approximation are presented for two special cases. We show results for HHG by plasma ablation in a bichromatic linearly polarized laser field. We also consider the ATI process in bicircular field which consists of two coplanar counter-rotating circularly polarized fields.

  10. Evaluation of mitogen-induced responses in marine mammal and human lymphocytes by in-vitro exposure of butyltins and non-ortho coplanar PCBs

    International Nuclear Information System (INIS)

    Nakata, H.; Sakakibara, A.; Kanoh, M.; Kudo, S.; Watanabe, H.; Nagai, N.; Miyazaki, N.; Asano, Y.; Tanabe, S.

    2002-01-01

    Butyltins may affect the immune response in marine mammals. - The effects of exposure to butyltin compounds (BTs: tributyltin; TBT, dibutyltin; DBT and monobutyltin; MBT) and non-ortho coplanar PCBs (IUPAC 77, 126 and 169) on marine mammals and human lymphocyte were evaluated. Peripheral blood mononuclear cells (PBMCs) isolated from Dall's porpoises (Phocoenoides dalli), bottlenose dolphins (Tursiops truncatus), a California sealion (Zalophus californianus), a larga seal (Phoca largha) and humans (Homo sapiens) were exposed at varying concentrations of BTs and coplanar PCBs. Concanavalin A (Con A)-stimulated mitogenesis found significantly suppressed (P<0.01) when the cells were exposed at 300 nM (89 ng/ml) of TBT and 330 nM of DBT (77 ng/ml), while MBT showed little cytotoxicity at treatment levels of up to 3600 nM (620 ng/ml). BTs concentrations in the liver of Dall's porpoises from Japanese coastal waters ranged between 81-450 ng/g for TBT and 200-1100 ng/g (wet wt.) for DBTs, which is greater than the cytotoxic levels registered in this study. In contrast, non-ortho coplanar PCBs did not suppress cell proliferation at concentrations of up to 30 nM (10 ng/ml). The residue levels of coplanar PCBs in the blubber of Dall's porpoises were 0.12-1.3 ng/g, which were one order of lower than those levels that do cell proliferation. When cells were exposed to a mixture of TBT/DBTand coplanar PCBs, the proliferation was significantly reduced to 33 nM DBT plus 34 nM CB-77 and 33 nM DBT plus 28 nM CB-169 mixtures, respectively. The investigations relating the contaminant-induced immunosuppression in marine mammals have been focused on persistent organochlorines such as PCBs, pesticides and dioxin compounds. However, this study suggested the possibility of BTs could also pose a serious threat to the immune functions in free-ranging marine mammals and humans

  11. Evaluation of mitogen-induced responses in marine mammal and human lymphocytes by in-vitro exposure of butyltins and non-ortho coplanar PCBs

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, H.; Sakakibara, A.; Kanoh, M.; Kudo, S.; Watanabe, H.; Nagai, N.; Miyazaki, N.; Asano, Y.; Tanabe, S

    2002-12-01

    Butyltins may affect the immune response in marine mammals. - The effects of exposure to butyltin compounds (BTs: tributyltin; TBT, dibutyltin; DBT and monobutyltin; MBT) and non-ortho coplanar PCBs (IUPAC 77, 126 and 169) on marine mammals and human lymphocyte were evaluated. Peripheral blood mononuclear cells (PBMCs) isolated from Dall's porpoises (Phocoenoides dalli), bottlenose dolphins (Tursiops truncatus), a California sealion (Zalophus californianus), a larga seal (Phoca largha) and humans (Homo sapiens) were exposed at varying concentrations of BTs and coplanar PCBs. Concanavalin A (Con A)-stimulated mitogenesis found significantly suppressed (P<0.01) when the cells were exposed at 300 nM (89 ng/ml) of TBT and 330 nM of DBT (77 ng/ml), while MBT showed little cytotoxicity at treatment levels of up to 3600 nM (620 ng/ml). BTs concentrations in the liver of Dall's porpoises from Japanese coastal waters ranged between 81-450 ng/g for TBT and 200-1100 ng/g (wet wt.) for DBTs, which is greater than the cytotoxic levels registered in this study. In contrast, non-ortho coplanar PCBs did not suppress cell proliferation at concentrations of up to 30 nM (10 ng/ml). The residue levels of coplanar PCBs in the blubber of Dall's porpoises were 0.12-1.3 ng/g, which were one order of lower than those levels that do cell proliferation. When cells were exposed to a mixture of TBT/DBTand coplanar PCBs, the proliferation was significantly reduced to 33 nM DBT plus 34 nM CB-77 and 33 nM DBT plus 28 nM CB-169 mixtures, respectively. The investigations relating the contaminant-induced immunosuppression in marine mammals have been focused on persistent organochlorines such as PCBs, pesticides and dioxin compounds. However, this study suggested the possibility of BTs could also pose a serious threat to the immune functions in free-ranging marine mammals and humans.

  12. Flow measurement in a 170-MW hydraulic turbine using the Gibson method; Medicion del flujo de una turbina hidraulica de 170 MW utilizando el metodo Gibson

    Energy Technology Data Exchange (ETDEWEB)

    Urquiza, Gustavo [Universidad Autonoma del Estado de Morelos (Mexico); Adamkowski, Adam [The Szewalski Institute of Fluid-Flow Machinery (Poland); Kubiak, Janusz; Sierra, Fernando [Universidad Autonoma del Estado de Morelos (Mexico); Janicki, Waldemar [The Szewalski Institute of Fluid-Flow Machinery (Poland); Fernandez, J. Manuel [Comision Federal de Electricidad (Mexico)

    2007-07-15

    This paper describes the methodology applied for measuring water flow through a 170-MW hydraulic turbine. The flow rate was measured using the pressure-time method, also known as the Gibson method. This method uses the well-known water hammer phenomenon in pipelines; in turbine penstocks, for instance. The version of this method used here is based on measuring, during total stop of the water stream, the time-history of pressure change in one section of the turbine penstock and relate it to the pressure in the upper reservoir to which the penstock is connected. The volumetric flow rate is determined from the relevant integration of the measured temporary pressure rise. Flow measurement was possible this way because the influence of the penstock inlet was negligible as far as an error of the measurement is concerned. The length of the penstock was 300 m. Previous experience and a standard IEC-41-1991 were the criteria adopted and applied. A fast and efficient acquisition system, including a 16 bit card, was used. The flow rate was calculated using a computer program developed and tested on several cases. The results obtained with the Gibson method were used for calibration of the on-line flow measuring system based on the Winter-Kennedy method as one of the index methods. This method is very often used for continuous monitoring of the flow rate through hydraulic turbines, when the calibration has been done on site by using the results of measurements obtained by the absolute method. Having measured the flow rate and output power, the efficiency was calculated for any operating conditions. A curve showing the best operating conditions based on the highest efficiency is presented and discussed. The details of the instrumentation, its installation, and the results obtained are discussed in the paper. [Spanish] Este articulo describe la metodologia aplicada para la medicion del flujo en una turbina hidraulica de 170 MW. El flujo se midio utilizando el metodo de presion

  13. Flow in potential cascades by means of the finite element method; Flujo en cascadas potenciales mediante el metodo del elemento finito

    Energy Technology Data Exchange (ETDEWEB)

    Sosa Cordero, Rodolfo; Fernandez Valencia, Gonzalo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    This article presents a mathematical model and its solution by means of the finite element method with approximate Garlekin formulation, for the flow analysis in a circular cascade, in a surface of revolution current of a turbo- machine, that can be axial, mixed or radial. To the revolution surface an agreed transformation is applied to obtain a plane, eliminating in this form one term in the equation succeeding in avoiding an iterative solution. Likewise, the finite element method allows to solve the equation in partial derivatives of the elliptical type in its quasi-harmonic form. Additionally, the method followed to introduce the contour conditions is presented; specially, the Kutta-Joukowsky conditions and the one of periodicity, which distinguishes this problem from the classical problems of ideal flows evaluated in the contour. [Espanol] En este articulo se presenta un modelo matematico y su solucion mediante el empleo del metodo del elemento finito con formulacion aproximada de Galerkin, para el analisis del flujo en una cascada circular, en una superficie de corriente de revolucion de una turbomaquina, que puede ser axial, mixta o radial. A la superficie de revolucion se le aplica una transformacion conforme para obtener un plano, eliminando de esta forma un termino en la ecuacion logrando evitar la solucion iterativa. Asimismo, el metodo del elemento finito permite resolver la ecuacion en derivadas parciales del tipo eliptico en su forma cuasiarmonica. Se presenta, ademas, el metodo seguido para introducir las condiciones de contorno; en especial, las condiciones de Kutta-Joukowsky y la de periodicidad, que distinguen a este problema de los problemas clasicos de flujos ideales valuados en el contorno.

  14. Flow in potential cascades by means of the finite element method; Flujo en cascadas potenciales mediante el metodo del elemento finito

    Energy Technology Data Exchange (ETDEWEB)

    Sosa Cordero, Rodolfo; Fernandez Valencia, Gonzalo [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    This article presents a mathematical model and its solution by means of the finite element method with approximate Garlekin formulation, for the flow analysis in a circular cascade, in a surface of revolution current of a turbo- machine, that can be axial, mixed or radial. To the revolution surface an agreed transformation is applied to obtain a plane, eliminating in this form one term in the equation succeeding in avoiding an iterative solution. Likewise, the finite element method allows to solve the equation in partial derivatives of the elliptical type in its quasi-harmonic form. Additionally, the method followed to introduce the contour conditions is presented; specially, the Kutta-Joukowsky conditions and the one of periodicity, which distinguishes this problem from the classical problems of ideal flows evaluated in the contour. [Espanol] En este articulo se presenta un modelo matematico y su solucion mediante el empleo del metodo del elemento finito con formulacion aproximada de Galerkin, para el analisis del flujo en una cascada circular, en una superficie de corriente de revolucion de una turbomaquina, que puede ser axial, mixta o radial. A la superficie de revolucion se le aplica una transformacion conforme para obtener un plano, eliminando de esta forma un termino en la ecuacion logrando evitar la solucion iterativa. Asimismo, el metodo del elemento finito permite resolver la ecuacion en derivadas parciales del tipo eliptico en su forma cuasiarmonica. Se presenta, ademas, el metodo seguido para introducir las condiciones de contorno; en especial, las condiciones de Kutta-Joukowsky y la de periodicidad, que distinguen a este problema de los problemas clasicos de flujos ideales valuados en el contorno.

  15. Method of identifying the friction of rotors using the wavelet transform; Metodo para identificar el rozamiento de rotores utilizado la transformada wavelet

    Energy Technology Data Exchange (ETDEWEB)

    Jauregui Correa, Juan Carlos; Rubio Cerda, Eduardo; Gonzalez Brambila, Oscar [CIATEQ, A.C., Queretaro (Mexico)

    2007-11-15

    The modern processes of signal analysis that measure mechanical vibrations are based on the fast transform of Fourier (FFT), nevertheless, this method is not able to identify transient phenomena nor of nonlinear nature. Although many efforts have been made to try to identify these phenomena in the frequency spectra, it is not possible to correlate the spectra with the physical characteristics of this type of phenomena. Within these phenomena on the rubbing of a rotor against the housing or trunnion of a bearing, this phenomenon has a nonlinear behavior, as it is demonstrated in this paper. In the first part a method based on the of signal analysis type wavelets is presented and how this technique can be used to predict transient and nonlinear phenomena. Once defined the method, its application in the identification of the friction of rotors is demonstrated. With this, one demonstrates that the method presented in this paper allows to also identifying in real time the rubbing phenomenon and also that it can be used as an of analysis technique in the preventive maintenance systems. [Spanish] Los procesos modernos de analisis de senales que miden vibraciones mecanicas se basan en la transformada rapida de Fourier (FFT por sus siglas en ingles), sin embargo, este metodo no es capaz de identificar fenomenos transitorios ni de naturaleza no lineal. A pesar de que se han hecho muchos esfuerzos para tratar de identificar estos fenomenos en los espectros de frecuencia, no es posible correlacionar el espectro con las caracteristicas fisicas de este tipo de fenomenos. Dentro de estos fenomenos sobre el rozamiento de un rotor contra la carcasa o munon de una chumacera, este fenomeno tiene un comportamiento no lineal, como se demuestra en este trabajo. En la primera parte se presenta un metodo basado en el analisis de senales tipo wavelets y como esta tecnica puede utilizarse para predecir fenomenos transitorios y no lineales. Una vez definido el metodo, se demuestra su

  16. Cone beam CT imaging with limited angle of projections and prior knowledge for volumetric verification of non-coplanar beam radiation therapy: a proof of concept study

    Science.gov (United States)

    Meng, Bowen; Xing, Lei; Han, Bin; Koong, Albert; Chang, Daniel; Cheng, Jason; Li, Ruijiang

    2013-11-01

    Non-coplanar beams are important for treatment of both cranial and noncranial tumors. Treatment verification of such beams with couch rotation/kicks, however, is challenging, particularly for the application of cone beam CT (CBCT). In this situation, only limited and unconventional imaging angles are feasible to avoid collision between the gantry, couch, patient, and on-board imaging system. The purpose of this work is to develop a CBCT verification strategy for patients undergoing non-coplanar radiation therapy. We propose an image reconstruction scheme that integrates a prior image constrained compressed sensing (PICCS) technique with image registration. Planning CT or CBCT acquired at the neutral position is rotated and translated according to the nominal couch rotation/translation to serve as the initial prior image. Here, the nominal couch movement is chosen to have a rotational error of 5° and translational error of 8 mm from the ground truth in one or more axes or directions. The proposed reconstruction scheme alternates between two major steps. First, an image is reconstructed using the PICCS technique implemented with total-variation minimization and simultaneous algebraic reconstruction. Second, the rotational/translational setup errors are corrected and the prior image is updated by applying rigid image registration between the reconstructed image and the previous prior image. The PICCS algorithm and rigid image registration are alternated iteratively until the registration results fall below a predetermined threshold. The proposed reconstruction algorithm is evaluated with an anthropomorphic digital phantom and physical head phantom. The proposed algorithm provides useful volumetric images for patient setup using projections with an angular range as small as 60°. It reduced the translational setup errors from 8 mm to generally <1 mm and the rotational setup errors from 5° to <1°. Compared with the PICCS algorithm alone, the integration of rigid

  17. Identification of an enhancer element of class Pi glutathione S-transferase gene required for expression by a co-planar polychlorinated biphenyl.

    OpenAIRE

    Matsumoto, M; Imagawa, M; Aoki, Y

    1999-01-01

    3,3',4,4',5-Pentachlorobiphenyl (PenCB), one of the most toxic co-planar polychlorinated biphenyl congeners, specifically induces class Pi glutathione S-transferase (GSTP1) as well as cytochrome P-450 1A1 in primary cultured rat liver parenchymal cells [Aoki, Matsumoto and Suzuki (1993) FEBS Lett. 333, 114-118]. However, the 5'-flanking sequence of the GSTP1 gene does not contain a xenobiotic responsive element, to which arylhydrocarbon receptor binds. Using a chloramphenicol acetyltransferas...

  18. Plan Quality and Treatment Efficiency for Radiosurgery to Multiple Brain Metastases: Non-Coplanar RapidArc vs Gamma Knife

    Directory of Open Access Journals (Sweden)

    Haisong eLiu

    2016-02-01

    Full Text Available Objectives: This study compares the dosimetry and efficiency of two modern radiosurgery (SRS modalities for multiple brain metastases (Gamma Knife and LINAC-based RapidArc/volumetric modulated arc therapy, with a special focus on the comparison of low dose spread.Methods: Six patients with three or four small brain metastases were used in this study. The size of targets varied from 0.1 ~ 10.5 cc. SRS doses were prescribed according to size of lesions. SRS plans were made using both Gamma Knife® Perfexion and a single-isocenter, multiple non-coplanar RapidArc®. Dosimetric parameters analyzed included RTOG conformity index (CI, gradient index (GI, 12 Gy isodose volume (V12Gy for each target, and the dose spread (Dspread for each plan. Dspread reflects SRS plan’s capability of confining radiation to within the local vicinity of the lesion and to not spread out to the surrounding normal brain tissues. Each plan has a dose (Dspread, such that once dose decreases below Dspread (on total tissue DVH, isodose volume starts increasing dramatically. Dspread is defined as that dose when volume increase first exceeds 20 cc per 0.1 Gy dose decrease. Results: RapidArc SRS has smaller CI (1.19 ±0.14 vs. 1.50 ± 0.16, p<0.001 and larger GI (4.77 ± 1.49 vs. 3.65 ± 0.98, p <0.01. V12Gy results were comparable (2.73 ± 1.38 cc vs. 3.06 ± 2.20 cc, p = 0.58. Moderate to lower dose spread, V6, V4.5, and V3, were also equivalent. Gamma Knife plans achieved better very low dose spread (≤3 Gy and also had slightly smaller Dspread, 1.9 Gy vs 2.5 Gy. Total treatment time for Gamma Knife is estimated between 60~100 min. Gamma Knife treatments are between 3~5 times longer compared to RapidArc treatment techniques.Conclusion: Dosimetric parameters reflecting prescription dose conformality (CI, dose fall off (GI, radiation necrosis indicator (V12Gy, and dose spread (Dspread were compared between Gamma Knife SRS and RapidArc SRS for multi-mets. RapidArc plans have

  19. A Ka-band low-noise amplifier with a coplanar waveguide (CPW) structure with 0.15-μm GaAs pHEMT technology

    International Nuclear Information System (INIS)

    Wu Chia-Song; Chang Chien-Huang; Liu Hsing-Chung; Lin Tah-Yeong; Wu Hsien-Ming

    2010-01-01

    This investigation explores a low-noise amplifier (LNA) with a coplanar waveguide (CPW) structure, in which a two-stage amplifier is associated with a cascade schematic circuit, implemented in 0.15-μm GaAs pseudomorphic high electron mobility transistor (pHEMT) technology in a Ka-band (26.5-40.0 GHz) microwave monolithic integrated circuit (MMIC). The experimental results demonstrate that the proposed LNA has a peak gain of 12.53 dB at 30 GHz and a minimum noise figure of 3.3 dB at 29.5 GHz, when biased at a V ds of 2 V and a V gs of -0.6 V with a drain current of 16 mA in the circuit. The results show that the millimeter-wave LNA with coplanar waveguide structure has a higher gain and wider bandwidth than a conventional circuit. Finally, the overall LNA characterization exhibits high gain and low noise, indicating that the LNA has a compact circuit and favorable RF characteristics. The strong RF character exhibited by the LNA circuit can be used in millimeter-wave circuit applications. (semiconductor integrated circuits)

  20. Treatment planning for SBRT using automated field delivery: A case study

    International Nuclear Information System (INIS)

    Ritter, Timothy A.; Owen, Dawn; Brooks, Cassandra M.; Stenmark, Matthew H.

    2015-01-01

    Stereotactic body radiation therapy (SBRT) treatment planning and delivery can be accomplished using a variety of techniques that achieve highly conformal dose distributions. Herein, we describe a template-based automated treatment field approach that enables rapid delivery of more than 20 coplanar fields. A case study is presented to demonstrate how modest adaptations to traditional SBRT planning can be implemented to take clinical advantage of this technology. Treatment was planned for a left-sided lung lesion adjacent to the chest wall using 25 coplanar treatment fields spaced at 11° intervals. The plan spares the contralateral lung and is in compliance with the conformality standards set forth in Radiation Therapy and Oncology Group protocol 0915, and the dose tolerances found in the report of the American Association of Physicists in Medicine Task Group 101. Using a standard template, treatment planning was accomplished in less than 20 minutes, and each 10 Gy fraction was delivered in approximately 5.4 minutes. For those centers equipped with linear accelerators capable of automated treatment field delivery, the use of more than 20 coplanar fields is a viable SBRT planning approach and yields excellent conformality and quality combined with rapid planning and treatment delivery. Although the case study discusses a laterally located lung lesion, this technique can be applied to centrally located tumors with similar results

  1. SU-F-BRB-12: A Novel Haar Wavelet Based Approach to Deliver Non-Coplanar Intensity Modulated Radiotherapy Using Sparse Orthogonal Collimators

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, D; Ruan, D; Low, D; Sheng, K [Deparment of Radiation Oncology, University of California Los Angeles, Los Angeles, CA (United States); O’Connor, D [Deparment of Mathematics, University of California Los Angeles, Los Angeles, CA (United States); Boucher, S [RadiaBeam Technologies, Santa Monica, CA (United States)

    2015-06-15

    Purpose: Existing efforts to replace complex multileaf collimator (MLC) by simple jaws for intensity modulated radiation therapy (IMRT) resulted in unacceptable compromise in plan quality and delivery efficiency. We introduce a novel fluence map segmentation method based on compressed sensing for plan delivery using a simplified sparse orthogonal collimator (SOC) on the 4π non-coplanar radiotherapy platform. Methods: 4π plans with varying prescription doses were first created by automatically selecting and optimizing 20 non-coplanar beams for 2 GBM, 2 head & neck, and 2 lung patients. To create deliverable 4π plans using SOC, which are two pairs of orthogonal collimators with 1 to 4 leaves in each collimator bank, a Haar Fluence Optimization (HFO) method was used to regulate the number of Haar wavelet coefficients while maximizing the dose fidelity to the ideal prescription. The plans were directly stratified utilizing the optimized Haar wavelet rectangular basis. A matching number of deliverable segments were stratified for the MLC-based plans. Results: Compared to the MLC-based 4π plans, the SOC-based 4π plans increased the average PTV dose homogeneity from 0.811 to 0.913. PTV D98 and D99 were improved by 3.53% and 5.60% of the corresponding prescription doses. The average mean and maximal OAR doses slightly increased by 0.57% and 2.57% of the prescription doses. The average number of segments ranged between 5 and 30 per beam. The collimator travel time to create the segments decreased with increasing leaf numbers in the SOC. The two and four leaf designs were 1.71 and 1.93 times more efficient, on average, than the single leaf design. Conclusion: The innovative dose domain optimization based on compressed sensing enables uncompromised 4π non-coplanar IMRT dose delivery using simple rectangular segments that are deliverable using a sparse orthogonal collimator, which only requires 8 to 16 leaves yet is unlimited in modulation resolution. This work is

  2. TH-EF-BRB-05: 4pi Non-Coplanar IMRT Beam Angle Selection by Convex Optimization with Group Sparsity Penalty

    International Nuclear Information System (INIS)

    O’Connor, D; Nguyen, D; Voronenko, Y; Yin, W; Sheng, K

    2016-01-01

    Purpose: Integrated beam orientation and fluence map optimization is expected to be the foundation of robust automated planning but existing heuristic methods do not promise global optimality. We aim to develop a new method for beam angle selection in 4π non-coplanar IMRT systems based on solving (globally) a single convex optimization problem, and to demonstrate the effectiveness of the method by comparison with a state of the art column generation method for 4π beam angle selection. Methods: The beam angle selection problem is formulated as a large scale convex fluence map optimization problem with an additional group sparsity term that encourages most candidate beams to be inactive. The optimization problem is solved using an accelerated first-order method, the Fast Iterative Shrinkage-Thresholding Algorithm (FISTA). The beam angle selection and fluence map optimization algorithm is used to create non-coplanar 4π treatment plans for several cases (including head and neck, lung, and prostate cases) and the resulting treatment plans are compared with 4π treatment plans created using the column generation algorithm. Results: In our experiments the treatment plans created using the group sparsity method meet or exceed the dosimetric quality of plans created using the column generation algorithm, which was shown superior to clinical plans. Moreover, the group sparsity approach converges in about 3 minutes in these cases, as compared with runtimes of a few hours for the column generation method. Conclusion: This work demonstrates the first non-greedy approach to non-coplanar beam angle selection, based on convex optimization, for 4π IMRT systems. The method given here improves both treatment plan quality and runtime as compared with a state of the art column generation algorithm. When the group sparsity term is set to zero, we obtain an excellent method for fluence map optimization, useful when beam angles have already been selected. NIH R43CA183390, NIH R01CA

  3. L’utilizzo della ricostruzione nella comunicazione del patrimonio archeologico. L’approccio, il metodo, le finalità e alcuni spunti di discussione.

    Directory of Open Access Journals (Sweden)

    Elena Bacci

    2010-05-01

    In questo contributo si focalizza l’attenzione sulla ricostruzione grafica e virtuale del patrimonio e sulle sensazioni che la ricostruzione evoca nel fruitore del messaggio culturale. La ricostruzione si attua mediante la collaborazione tra archeologo e illustratore e costituisce un momento di verifica visiva dell’interpretazione archeologica e uno strumento di comunicazione del dato archeologico fruibile a più livelli. Ciò avviene grazie allo scambio costante di informazioni (dati scientifici e proposte di ricostruzione e il confronto che ne deriva determina i metodi e le fasi di avanzamento del progetto. Il metodo si basa sull’integrazione delle immagini 3D con il disegno tradizionale ed è finalizzato alla trasposizione del dato archeologico, in modo tale da garantire alla ricostruzione il duplice requisito di soddisfazione estetica e credibilità scientifica.

  4. Non-Destructive Methods for Determining Burn-Up in Nuclear Fuel; Methodes Non Destructives d'Evaluation du Taux de Combustion dans le Combustible Nucleaire; Metody opredeleniya vygoraniya v yadernom toplive bez razrusheniya obraztsa; Metodos No Destructivos para Determinai el Grado de Combustion de los Elementos Combustibles Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    McGonnagle, W. J. [Illinois Institute of Technology, Chicago, IL (United States)

    1966-02-15

    Non-destructive methods for quantitative measurement of burn-up in nuclear reactor fuel elements are useful and desirable. The ideal method for fuel assay would be one that requires no special information about the neutron spectra, radiation history, or cooling time. The irradiated fuel element contains a record of the fuel burn-up. This record is in the form of radioactive and stable isotopes resulting from the fission process. Unfortunately, in the non-destructive as well as the destructive fuel assay methods, the neutron spectrum, irradiation history, and cooling period influence this record. Likewise, the lack of precise nuclear data, such as values of nuclear cross-sections, affects any calculations that can be made. Another difficulty in the non-destructive assay is the presence of high radiation fields which contribute to the ''noise'' background of the measurements. The development of useful and realistic standards is difficult. The non-destructive burn-up methods do serve a useful purpose especially when an approximate value of burn-up is required quickly and economically even though in the present state of the art they lack the desired precision and accuracy. Several non-destructive methods for determining burn-up have been used, are being evaluated, or have been proposed. Various types of spectrometers including the bent crystal, magnetic Compton, Compton coincidence, and scintillation have been used to analyse the gamma radiation from the radioactive material formed during the fission process. Other non-destructive methods include foil activation, neutron transmission, activation analysis, measurement of capture gamma rays, and the measurement of prompt and delayed neutrons. The basic principles of each of the above instruments and methods, their sensitivities and their limitations will be reviewed. Non-destructive methods using stable isotopes produced during the fission process are proposed. In the use of stable isotopes, detailed irradiation history

  5. Journal Article: the National Dioxin Air Monitoring Network (Ndamn): Measurements of CDDs, CDFs and Coplanar PCBs at 15 Rural and 6 National Park Areas of the U.S.: June 1998-December 1999.

    Science.gov (United States)

    The U.S. EPA has established a National Dioxin Air Monitoring Network (NDAMN) to determine the temporal and geographical variability of atmospheric CDDs, CDFs and coplanar PCBs at rural and nonimpacted locations throughout the United States. Currently operating at 32 sampling st...

  6. Journal Article: the National Dioxin Air Monitoring Network (Ndamn): Measurements of CDDs, CDFs, and Coplanar PCBs at 18 Rural, 8 National Parks, and 2 Suburban Areas of the U.S.: Results for the Year 2000.

    Science.gov (United States)

    In June, 1998, the U.S. EPA established the National Dioxin Air Monitoring Network (NDAMN). The primary goal of NDAMN is determine the temporal and geographical variability of atmospheric CDDs, CDFs, and coplanar PCBs at rural and nonimpacted locations throughout the United Stat...

  7. Identification of an enhancer element of class Pi glutathione S-transferase gene required for expression by a co-planar polychlorinated biphenyl.

    Science.gov (United States)

    Matsumoto, M; Imagawa, M; Aoki, Y

    1999-01-01

    3,3',4,4',5-Pentachlorobiphenyl (PenCB), one of the most toxic co-planar polychlorinated biphenyl congeners, specifically induces class Pi glutathione S-transferase (GSTP1) as well as cytochrome P-450 1A1 in primary cultured rat liver parenchymal cells [Aoki, Matsumoto and Suzuki (1993) FEBS Lett. 333, 114-118]. However, the 5'-flanking sequence of the GSTP1 gene does not contain a xenobiotic responsive element, to which arylhydrocarbon receptor binds. Using a chloramphenicol acetyltransferase assay we demonstrate here that the enhancer termed GSTP1 enhancer I (GPEI) is necessary for the stimulation by PenCB of GSTP1 gene expression in primary cultured rat liver parenchymal cells. GPEI is already known to contain a dyad of PMA responsive element-like elements oriented palindromically. It is suggested that a novel signal transduction pathway activated by PenCB contributes to the stimulation of GSTP1 expression. PMID:10051428

  8. Deformation bands and dislocation structures of [1-bar 5 5] coplanar double-slip-oriented copper single crystal under cyclic deformation

    International Nuclear Information System (INIS)

    Li, Y.; Li, S.X.; Li, G.Y.

    2004-01-01

    The features of surface morphology and dislocation structure of [1-bar 5 5] coplanar double-slip-oriented copper single crystal under cyclic deformation at a constant plastic shear strain amplitude of 2x10 -3 were studied using optical microscope (OP) and electron channelling contrast imaging (ECCI) in the scanning electron microscope (SEM). Experimental results show that there are two sets of the secondary type of deformation band (DBII) formed in the specimen. The geometry relationship of the two sets of deformation bands (DBs) and slip band (SB) are given. The habit planes of DBIIs are close to (1-bar 0 1) and (1-bar 1 0) plane, respectively. The surface dislocation structures in the specimen including vein, irregular dislocation cells and dislocation walls were also observed. The typical dislocation structure in DBII is the dislocation walls

  9. Possible Outcomes of Coplanar High-eccentricity Migration: Hot Jupiters, Close-in Super-Earths, and Counter-orbiting Planets

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Yuxin; Masuda, Kento; Suto, Yasushi, E-mail: yuxin@utap.phys.s.u-tokyo.ac.jp [Department of Physics, The University of Tokyo, Tokyo 113-0033 (Japan)

    2017-02-01

    We investigate the formation of close-in planets in near-coplanar eccentric hierarchical triple systems via the secular interaction between an inner planet and an outer perturber (Coplanar High-eccentricity Migration; CHEM). We generalize the previous work on the analytical condition for successful CHEM for point masses interacting only through gravity by taking into account the finite mass effect of the inner planet. We find that efficient CHEM requires that the systems should have m {sub 1}≪m {sub 0} and m {sub 1} ≪ m {sub 2}. In addition to the gravity for point masses, we examine the importance of the short-range forces, and provide an analytical estimate of the migration timescale. We perform a series of numerical simulations in CHEM for systems consisting of a Sun-like central star, giant gas inner planet, and planetary outer perturber, including the short-range forces and stellar and planetary dissipative tides. We find that most of such systems end up with a tidal disruption; a small fraction of the systems produce prograde hot Jupiters (HJs), but no retrograde HJ. In addition, we extend CHEM to super-Earth mass range, and show that the formation of close-in super-Earths in prograde orbits is also possible. Finally, we carry out CHEM simulation for the observed hierarchical triple and counter-orbiting HJ systems. We find that CHEM can explain a part of the former systems, but it is generally very difficult to reproduce counter-orbiting HJ systems.

  10. A method for optimization of patient dose estimation in conventional radiology; Un metodo per l'ottimizzazione della stima della dose al paziente nella radiologia tradizionale

    Energy Technology Data Exchange (ETDEWEB)

    Tofani, A.; Del Corona, A. [Azienda Unita' Sanitaria Locale 6, Livorno (Italy). Unita' Ospedaliera di Fisica Sanitaria; Niespolo, A. [Azienda Ospedaliera Pisana, Pisa (Italy). Unita' Ospedaliera di Fisica Sanitaria

    2000-05-01

    found to depend on the average body surface, a parameter which takes into account both patient height and mass. Thus, determining the normalization factor for each projection and each view allows to estimate the absorbed dose under different geometrical conditions. The method has been verified by considering four of the most common X-ray procedures (chest AP, cervical spine LAT, lumbar spine AP and head LAT). The average error on dose estimation is about 13 %. In the very next future the method will be extended to all the projections and views of ICRP Report no. 34, and we plant to integrate the described algorithm in a computer program devoted to the automatic computation of patient dose. [Italian] Il metodo raccomandato dalla International Commission on Radiological Protection (ICRP) nel suo Report n. 34(1982) per il calcolo della dose al paziente negli esami di radiodiagnostica e' basato su dati dosimetrici tabulati ottenuti mediante simulazioni Monte Carlo su fantocci antropomorfi descritti da semplici funzioni matematiche. Nel caso del calcolo della dose per un paziente adulto, le limitazioni principali di questo metodo sono due: in primo luogo i parametri geometrici dell'esame - e in particolare la distanza fuoco-pellicola e il formato della pellicola- sono fissi, e questo rende problematico l'utilizzo dei dati dosimetrici nelle condizioni effettive in cui si e' svolto l'esame, che in genere non coincideranno con quelle standard ICRP. Inoltre quando le dimensioni e la massa del paziente differiscono sensibilmente da quelle del fantoccio utilizzato nelle simulazioni (il cosidetto uomo di riferimento, di altezza pari a 174 cm e massa di 70,9 Kg) il metodo ICRP puo' portare a errori considerevoli nella stima della dose. Lo scopo del presente lavoro e' quello di indicare una possibile via di uscita per superare queste limitazioni. L'algoritmo proposto in questo lavoro si basa sull'applicazione del metodo suggerito da Huda e

  11. Fundamentos del metodo cientifico

    Directory of Open Access Journals (Sweden)

    Badii, M. H.

    2004-01-01

    Full Text Available El objetivo de esta obra no radica en realizar una búsqueda exhaustiva de la literatura en el tema, sino, sentar las bases del método científico, notando los aspectos filosóficos e éticos de la ciencia. Se presentan los conceptos y definiciones fundamentales relacionados con la metodología de la investigación científica. Se maneja el concepto de la toma de los datos válidos como un requisito básico en cualquier trabajo científico. Se pone a disposición del lector un modelo denominado el ECOEE que es una herramienta poderosa para establecer puntos de comparación e discusión entre los resultados de diferentes trabajos científicos. Finalmente, ofrece unas sugerencias de que hacer o no hacer en cuanto a realizar un trabajo de investigación.

  12. Diagnostics of pre-breakdown light emission in a helium coplanar barrier discharge: the presence of neutral bremsstrahlung

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Z.; Morávek, T.; Ráhel’, J.; Čech, J.; Lalinský, Ondřej; Trunec, D.

    2017-01-01

    Roč. 26, č. 5 (2017), s. 1-10, č. článku 055025. ISSN 0963-0252 Institutional support: RVO:68081731 Keywords : dielectric barrier discharge * helium * single photon counting * bremsstrahlung * electric field * backward discharge * surface charge Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 3.302, year: 2016

  13. Ultra-high-speed oscillographic techniques; Techniques d'oscillographie ultra-rapide; Metody sverkhskorostnoj ostsillografii; Metodos oscilograficos ultrarrapidos

    Energy Technology Data Exchange (ETDEWEB)

    Abercrombie, S; Elphick, B; Foster, H [Atomic Weapons Research Establishment, Aldermaston (United Kingdom)

    1962-04-15

    100 {Omega}; e) Des resistances de complement a large bande, destinees a l'extraction des signaux de declenchement de la base de temps; / ) Des bases de temps fournissant des signaux de l'ordre de quelques nanosecondes et comportant des dispositifs de declenchement et de suppression du faisceau; g) Un appareil de prise de vues a grande ouverture. En conclusion, le memoire examine certaines applications de l'electronique nucleaire. (author) [Spanish] Despues de un resumen historico de los metodos de utilizacion de oscilografos para senales transitorias de alta velocidad, los autores examinan sus limites de aplicacion practica. En la memoria se pasa revista a los tubos de rayos catodicos apropiados para estos oscilografos, tomando en cuenta especialmente los tipos de deflexion por onda progresiva. En la memoria se estudian los siguientes componentes de un oscilografo completo para senales transitorias: a) Un tubo de rayos catodicos con deflexion por onda progresiva con conexion coaxial balanceada y una anchura de banda de 2 GHz; b) Un transformador inversor de fase con una impedancia caracteristica de 100 y 50 {Omega} y una anchura de banda de 1,5 kHz a 1,5 GHz; c) Resistencias de terminacion coaxial para frecuencias del orden de los GHz; d) Condensadores de acoplamiento compensados para usarlos en lineas coaxiales con frecuencias comprendidas entre 5 kHz y 3 GHz y 100 {Omega} de impedancia caracteristica; e) Atenuadores resistivos de banda ancha, para la extraccion de senales de disparo de base de tiempos; f) Bases de tiempo del orden de los nanosegundos, con dispositivos disparadores y supresores ; g) Una camara de gran apertura. Finalmente, los autores examinan las aplicaciones de estos oscilografos en la electronica nuclear. (author) [Russian] Posle kratkogo opisaniya ostsillograficheskogo metoda izucheniya sverkhskorostnykh perekhodnykh izluchenij obsuzhdayutsya prakticheskie vozmozhnosti ehtogo apparata. Daetsya obzor podkhodyashchikh katodnykh ehlektronnykh lamp

  14. 10 GHz Standing-Wave Coplanar Stripline on LiNbO3 Crystal for Radio to Optical-Wave Conversion

    Science.gov (United States)

    Darwis, F.; Wijayanto, Y. N.; Setiawan, A.; Mahmudin, D.; Rahman, A. N.; Daud, P.

    2018-04-01

    Recently, X-band radar systems are used widely for surveillance and navigation applications. Especially in archipelago or maritime country, the surveillance/navigation radar systems are required to monitoring critical areas and managing marine traffic. Accurate detection and fast analysis should be improved furthermore to provide security and safety condition. Therefore, several radar systems should be installed in many places to coverage the critical areas within radar networks. The radar network can be connected using optical fibers since it has extremely low propagation loss with optical-wave to carry-out the radar-wave. One important component in the scenario is a radio to optical-wave conversion component. In this paper, we report a 10 GHz radio to optical-wave conversion component using standing-wave coplanar stripline (CPS) on LiNbO3 optical crystal as the substrate. The standing-wave CPS electrodes with narrow slot are arranged in an array structure. An optical waveguide is located close to the narrow slot. The CPS electrodes were analysed using electromagnetic analysis software for 10 GHz operational frequency. Responses for slot width and electrode length variation are reported. As results, return loss of -14.580 dB and -19.517 dB are obtained for single and array CPS electrodes respectively. Optimization of the designed radio to optical-wave conversion devices was also done.

  15. Evaluation of accuracy about 2D vs 3D real-time position management system based on couch rotation when non-coplanar respiratory gated radiation therapy

    International Nuclear Information System (INIS)

    Kwon, Kyung Tae; Kim, Jung Soo; Sim, Hyun Sun; Min, Jung Whan; Son, Soon Yong; Han, Dong Kyoon

    2016-01-01

    Because of non-coplanar therapy with couch rotation in respiratory gated radiation therapy, the recognition of marker movement due to the change in the distance between the infrared camera and the marker due to the rotation of the couch is called RPM (Real-time The purpose of this paper is to evaluate the accuracy of motion reflections (baseline changes) of 2D gating configuration (two dot marker block) and 3D gating configuration (six dot marker block). The motion was measured by varying the couch angle in the clockwise and counterclockwise directions by 10° in the 2D gating configuration. In the 3D gating configuration, the couch angle was changed by 10° in the clockwise direction and compared with the baseline at the reference 0°. The reference amplitude was 1.173 to 1.165, the couch angle at 20° was 1.132, and the couch angle at 1.0° was 1.083. At 350° counterclockwise, the reference amplitude was 1.168 to 1.157, the couch angle at 340° was 1.124, and the couch angle at 330° was 1.079. In this study, the phantom is used to quantitatively evaluate the value of the amplitude according to couch change

  16. Evaluation of accuracy about 2D vs 3D real-time position management system based on couch rotation when non-coplanar respiratory gated radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Kyung Tae; Kim, Jung Soo [Dongnam Health University, Suwon (Korea, Republic of); Sim, Hyun Sun [College of Health Sciences, Korea University, Seoul (Korea, Republic of); Min, Jung Whan [Shingu University College, Sungnam (Korea, Republic of); Son, Soon Yong [Wonkwang Health Science University, Iksan (Korea, Republic of); Han, Dong Kyoon [College of Health Sciences, EulJi University, Daejeon (Korea, Republic of)

    2016-12-15

    Because of non-coplanar therapy with couch rotation in respiratory gated radiation therapy, the recognition of marker movement due to the change in the distance between the infrared camera and the marker due to the rotation of the couch is called RPM (Real-time The purpose of this paper is to evaluate the accuracy of motion reflections (baseline changes) of 2D gating configuration (two dot marker block) and 3D gating configuration (six dot marker block). The motion was measured by varying the couch angle in the clockwise and counterclockwise directions by 10° in the 2D gating configuration. In the 3D gating configuration, the couch angle was changed by 10° in the clockwise direction and compared with the baseline at the reference 0°. The reference amplitude was 1.173 to 1.165, the couch angle at 20° was 1.132, and the couch angle at 1.0° was 1.083. At 350° counterclockwise, the reference amplitude was 1.168 to 1.157, the couch angle at 340° was 1.124, and the couch angle at 330° was 1.079. In this study, the phantom is used to quantitatively evaluate the value of the amplitude according to couch change.

  17. High-temperature superconducting coplanar-waveguide quarter-wavelength resonator with odd- and even-mode resonant frequencies for dual-band bandpass filter

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, Kei; Takagi, Yuta; Narahashi, Shoichi [Research Laboratories, NTT DOCOMO, INC., 3-6 Hikari-no-oka Yokosuka, Kanagawa 239-8536 Japan (Japan); Nojima, Toshio, E-mail: satokei@nttdocomo.co.j [Graduate School of Information Science and Technology, Hokkaido University, Kita 14, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0814 Japan (Japan)

    2010-06-01

    This paper presents a high-temperature superconducting coplanar-waveguide quarter-wavelength resonator that has two different resonant modes for use in a dual-band bandpass filter (DBPF). An RF filter with multiple passbands such as the DBPF is a basic element that is expected to achieve broadband transmission by using separated frequency bands aggregately and simultaneously in future mobile communication systems. The proposed resonator has a folded center conductor and two open stubs that are aligned close to it. The odd- and even-mode resonant frequencies are configured using the space between the folded center conductor and the open stubs. It is easy to configure the odd- and even-mode coupling coefficients independently because the two resonant modes have different current density distributions. Consequently, a DBPF with two different bandwidths can be easily designed. This paper presents three design examples for a four-pole Chebyshev DBPF with different combinations of fractional bandwidths in order to investigate the validity of the proposed resonator. This paper also presents measured results of the DBPF based on the design examples from the standpoint of experimental investigation. The designed and measured frequency responses confirm that the proposed resonator is effective in achieving DBPFs not only with two of the same bandwidths but also with two different bandwidths.

  18. Cross-validation of two commercial methods for volumetric high-resolution dose reconstruction on a phantom for non-coplanar VMAT beams

    International Nuclear Information System (INIS)

    Feygelman, Vladimir; Stambaugh, Cassandra; Opp, Daniel; Zhang, Geoffrey; Moros, Eduardo G.; Nelms, Benjamin E.

    2014-01-01

    Background and purpose: Delta 4 (ScandiDos AB, Uppsala, Sweden) and ArcCHECK with 3DVH software (Sun Nuclear Corp., Melbourne, FL, USA) are commercial quasi-three-dimensional diode dosimetry arrays capable of volumetric measurement-guided dose reconstruction. A method to reconstruct dose for non-coplanar VMAT beams with 3DVH is described. The Delta 4 3D dose reconstruction on its own phantom for VMAT delivery has not been thoroughly evaluated previously, and we do so by comparison with 3DVH. Materials and methods: Reconstructed volumetric doses for VMAT plans delivered with different table angles were compared between the Delta 4 and 3DVH using gamma analysis. Results: The average γ (2% local dose-error normalization/2mm) passing rate comparing the directly measured Delta 4 diode dose with 3DVH was 98.2 ± 1.6% (1SD). The average passing rate for the full volumetric comparison of the reconstructed doses on a homogeneous cylindrical phantom was 95.6 ± 1.5%. No dependence on the table angle was observed. Conclusions: Modified 3DVH algorithm is capable of 3D VMAT dose reconstruction on an arbitrary volume for the full range of table angles. Our comparison results between different dosimeters make a compelling case for the use of electronic arrays with high-resolution 3D dose reconstruction as primary means of evaluating spatial dose distributions during IMRT/VMAT verification

  19. Development of an analytic method for arsenic's determination in lime and tortilla; Desarrollo de un metodo analitico para determinacion de arsenico en cal y tortilla

    Energy Technology Data Exchange (ETDEWEB)

    Huato Soberanis, Julio; Ogura, Tetsuya [Universidad Autonoma de Guadalajara, Guadalajara, Jalisco (Mexico)

    1995-02-01

    A spectrophotometric method to determine As in tortilla and lime has been optimized, modifying the AsH{sub 3} generator. The reaction between arsin (AsH{sub 3}){sub 4} and diethyldithiocarbamate of Ag (AgDDC); was followed spectrophotometrically. The conditions under which the As remains in the ash during the calcination of the tortillas were studied. It was found that when they were heated in a quartz tube with a careful control of the air flow and oxygen, as well as the heating temperature, the arsenic loss in minimized. [Spanish] Se ha optimizado el metodo para determinar As en la tortilla y cal mediante espectrometria en el visible del color producido en la reaccion entre Arsina (AsH{sub 3}){sub 4} y dietilditiocarbamato de plata (AgDDC); modificando el generador de AsH{sub 3}. Se han buscado las condiciones en las que el arsenico permanece en las cenizas de la calcinacion de las tortillas; encontrandose que las tortillas deben calentarse en un tubo de cuarzo con control del flujo de aire y oxigeno asi como de la temperatura de calentamiento.

  20. Application of the identification methods from Hilbert and Prony to the study of oscillatory phenomena in electrical power systems; Aplicacion de los metodos de identificacion de Hilbert y Prony al estudio de fenomenos oscilatorios en sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Andrade Soto, Manuel Antonio

    2002-10-15

    In the present thesis work the application of identification techniques is investigated based on methods of spectral analysis to the study of the instantaneous characteristics of signals obtained by means of digital simulation of the dynamic behavior of the power system. The study focuses on the perspectives developed from two different approaches of analysis: the use of lineal methods of spectral analysis and the use of methods of non-lineal analysis, based on the concept of an analytical signal. The developed tools are applied to the study of two phenomena of electromechanical origin of different characteristics in complex power systems. A comparison between the results obtained is performed for these techniques and the possibility of its application is discussed for the problem of on-line identification in power systems. [Spanish] En el presente trabajo de tesis se investiga la aplicacion de tecnicas de identificacion basadas en metodos de analisis espectral al estudio de las caracteristicas instantaneas de senales obtenidas mediante simulacion digital del comportamiento dinamico del sistema de potencia. El estudio se centra en las aproximaciones desarrolladas desde dos enfoques distintos de analisis: la utilizacion de metodos lineales de analisis espectral y la utilizacion de metodos de analisis no lineal, basados en el concepto de una senal analitica. Las herramientas desarrolladas se aplican al estudio de dos fenomenos de origen electromecanico de caracteristicas distintas en sistemas complejos de potencia. Se hace una comparacion entre los resultados obtenidos por estas tecnicas y se discute la posibilidad de su aplicacion al problema de identificacion en linea en sistemas de potencia.

  1. Effects of in ovo exposure to PCBs (coplanar congener, kanechlor mixture, hydroxylated metabolite) on the developing cell-mediated immunity in chickens

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, J.; Matsuda, M.; Kawano, M.; Wakimoto, T. [Faculty of Agriculture, Ehime Univ., Matsuyama, Ehime (Japan); Kashima, Y. [Dept. of Hygiene, Yokohama City Univ. School of Medicine, Yokohama (Japan)

    2004-09-15

    Polychlorinated biphenyls (PCBs) are wide spread environmental contaminants and known to cause various adverse effects on health of human and wildlife. Immune system is one of the several targets for toxic effects of PCBs and its normal balance is often disrupted by the exposure of the compounds. For example, PCBs may induce immune suppression and result in increased susceptibility to bacterial and viral infections, or conversely, excessive immune enhancement may cause adverse outcomes including as autoimmune disease and anergy. Therefore immune function is regarded as one of an important endpoint in toxicological risk assessment. There are a number of studies shown that neonatal organisms perinatally exposed to polyhalogenated aromatic hydrocarbons (PHAHs) such as PCBs have severer effects on their immune system than adult. Dioxins and coplanar PCB congeners, structurally planar PHAHs are known to have high affinity for aryl hydrocarbon receptor (AhR). 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (TCDD) have the strongest affinity among such compounds and these are considered to act on immune system through AhR. On the other hand, such as non-planar PCB congeners with low affinity for AhR, which are abundantly contained in commercial PCB preparations have non-additive (antagonistic) effects on immune function. Prenatal exposure of TCDD to rodent induced abnormal lymphoid development in the thymus and thymus-dependent immune functions were remarkably disturbed. Although several experimental studies in mammals have been carried out on the developmental immunotoxicity of PCBs, there are still limited information available on avian species. Thus in this study, prenatal exposure to low level of PCBs and the effects on the developing immune system were investigated with chicken as a model animal of avian species, especially it is focused on the cell-mediated immune function.

  2. Esterification and hydrolysis of vitamin A in the liver of brook trout (Salvelinus fontinalis) and the influence of a coplanar polychlorinated biphenyl

    International Nuclear Information System (INIS)

    Ndayibagira, A.; Spear, P.A.

    1999-01-01

    Recent reports of extremely low retinoid stores in fish living in contaminated river systems prompted an initial investigation of the mechanisms of hepatic storage and mobilization in brook trout. Enzyme characterization in microsomes revealed a lecithin:retinol acyltransferase activity (LRAT) optimum in the alkaline range (pH 9.0; V max =0.6 nmol per mg prot. h -1 ; K m =10.2 μM) which is not known to occur in mammals, in addition to a secondary optimum at pH 6.5 typical of mammals. Acyl CoA:retinol acyltransferase (ARAT) kinetic parameters were quite different to those of mammals. The substrate affinity of trout ARAT (K m =1.6 μM) was approximately 22-fold greater than that of the rat while maximal velocity (V max =0.2 nmol per mg prot. h -1 ) was 18-fold less. Retinyl ester hydrolase activity (REH) was optimal under acid conditions (pH 4.2; V max =6.6 nmol per mg prot. h -1 ; K m =0.6 mM), was inhibited by a bile salt analogue and was greater in males than females. This REH was tentatively categorized as a bile salt-independent, acid retinyl ester hydrolase (BSI-AREH). REH was inhibited in a dose-dependent manner following in vivo exposure to a representative environmental contaminant the coplanar polychlorinated biphenyl (PCB), 3,3minutes or feet,4,4minutes or feet-tetrachlorobiphenyl (TCBP). Inhibition may be an indirect effect because enzyme activity was not affected by in vitro exposure of control microsomes. REH inhibition in the brook trout may affect the uptake of retinyl esters (REs) from chylomicron remnants as well as the mobilization of stored REs. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  3. Coligand-regulated assembly, fluorescence, and magnetic properties of Co(II) and Cd(II) complexes with a non-coplanar dicarboxylate

    Energy Technology Data Exchange (ETDEWEB)

    Xin, Ling-Yun [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Liu, Guang-Zhen, E-mail: gzliuly@126.com [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Ma, Lu-Fang [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Wang, Li-Ya [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang 473061 (China)

    2013-10-15

    A non-coplanar dicarboxylate ndca (H{sub 2}ndca=5-norbornene-2,3-dicarboxylic acid), combining with various dipyridyl-typed tectons, constructs six Cd(II)/Co(II) coordination polymers under hydrothermal conditions, namely [Co(ndca)(H{sub 2}O)]{sub n} (1), ([Co(ndca)(bpe)(H{sub 2}O)]·H{sub 2}O){sub n} (2), [Co(ndca)(bpa){sub 0.5}(H{sub 2}O)]{sub n} (3), [Cd(ndca)(bpe)(H{sub 2}O)]{sub n} (4), ([Cd(ndca)(bpa)(H{sub 2}O)]·0.5H{sub 2}O){sub n} (5), and ([Cd(ndca)(bpp) (H{sub 2}O)]·H{sub 2}O){sub n} (6) (bpe=1,2-di(4-pyridyl)ethylene, bpa=1,2-bi(4-pyridyl)ethane, and bpp=1,3-bis(4-pyridyl)propane). All these compounds contain various metal(II)–carboxylate motifs, including carboxylate binuclear (2, 4, 5), carboxylate chain (1, 6) and carboxylate layer (3), which are further extended by dipyridyl-typed coligands to afford a vast diversity of the structures with 2D pyknotic layers (1, 6), 2D open layer (5), 2D→3D interpenetrated networks (2,4), and 3D pillared-layer framework (3), respectively. In addition, fluorescent spectra of Cd(II) complexes and magnetic properties of Co(II) complexes are also given. - Graphical abstract: Six various cadmium(II)/cobalt(II)–organic frameworks were constructed by 5-norbornene-2,3-dicarboxylic acid and different bis(pyridine) rod-like tectons, and Cd (II) complexes exhibit blue–violet emissions, whereas Co (II) complexes show antiferromagnetic behaviours. Display Omitted.

  4. Coligand-regulated assembly, fluorescence, and magnetic properties of Co(II) and Cd(II) complexes with a non-coplanar dicarboxylate

    International Nuclear Information System (INIS)

    Xin, Ling-Yun; Liu, Guang-Zhen; Ma, Lu-Fang; Wang, Li-Ya

    2013-01-01

    A non-coplanar dicarboxylate ndca (H 2 ndca=5-norbornene-2,3-dicarboxylic acid), combining with various dipyridyl-typed tectons, constructs six Cd(II)/Co(II) coordination polymers under hydrothermal conditions, namely [Co(ndca)(H 2 O)] n (1), ([Co(ndca)(bpe)(H 2 O)]·H 2 O) n (2), [Co(ndca)(bpa) 0.5 (H 2 O)] n (3), [Cd(ndca)(bpe)(H 2 O)] n (4), ([Cd(ndca)(bpa)(H 2 O)]·0.5H 2 O) n (5), and ([Cd(ndca)(bpp) (H 2 O)]·H 2 O) n (6) (bpe=1,2-di(4-pyridyl)ethylene, bpa=1,2-bi(4-pyridyl)ethane, and bpp=1,3-bis(4-pyridyl)propane). All these compounds contain various metal(II)–carboxylate motifs, including carboxylate binuclear (2, 4, 5), carboxylate chain (1, 6) and carboxylate layer (3), which are further extended by dipyridyl-typed coligands to afford a vast diversity of the structures with 2D pyknotic layers (1, 6), 2D open layer (5), 2D→3D interpenetrated networks (2,4), and 3D pillared-layer framework (3), respectively. In addition, fluorescent spectra of Cd(II) complexes and magnetic properties of Co(II) complexes are also given. - Graphical abstract: Six various cadmium(II)/cobalt(II)–organic frameworks were constructed by 5-norbornene-2,3-dicarboxylic acid and different bis(pyridine) rod-like tectons, and Cd (II) complexes exhibit blue–violet emissions, whereas Co (II) complexes show antiferromagnetic behaviours. Display Omitted

  5. Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like coplanar polychlorinated biphenyls in mackerel obtained from the Japanese market, 1999-2003.

    Science.gov (United States)

    Nakatani, Tadashi; Yamano, Testuo

    2017-09-01

    This study analysed the concentrations and toxic-equivalent (TEQ) levels of dioxin congeners in mackerel commercially available in Japan in early 2000s. The content of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like coplanar polychlorinated biphenyls (DL-PCBs) was determined in 17 mackerel samples from different areas. TEQ levels in mackerel muscle were 0.78 pg TEQ g - 1 wet weight (wt) on average (range = 0.21-2.26 pg TEQ g - 1 wet wt) for PCDD/Fs (PCDDs plus PCDFs), 2.81 pg TEQ g - 1 wet wt on average (range = 1.02-8.5 pg TEQ g - 1 wet wt) for DL-PCBs, and 3.59 pg TEQ g - 1 wet wt on average (range = 1.24-10.8 pg g - 1 wet wt) for dioxins (PCDD/Fs plus DL-PCBs). The results revealed somewhat higher TEQ levels for dioxins compared with the other data for fish and shellfish in the Japanese market. TEQ levels were well correlated with mackerel body weight; the main contributors were tetra- and penta-CDD/Fs, some hexa-CDD/Fs, and all 12 DL-PCBs, which are known to have high bioaccumulation potential. In particular, PCB 126 was mostly responsible for the observed correlation of DL-PCB and dioxins-TEQ levels with mackerel body weight. The average daily intake of dioxins in terms of TEQ through mackerel consumption was estimated to be 4.81 pg TEQ/person/day, accounting for 7% of the total intake of dioxins-TEQ through fish and shellfish in Japan.

  6. The Comparative Accuracy of the 4 {pi} Liquid Scintillation Counting Method of Radioisotope Standardization; L'exactitude comparee de la methode de comptage 4 {pi} a scintillateurs liquides pour l'etalonnage des radioisotopes; Sravnitel'naya tochnost' 4 {pi} zhidkogo stsintillatsionnogo metoda podscheta standartiziruemykh radioizotopov; Exactitud del metodo de recuento con centelleador liquido 4 {pi} para normalizar radioisotopos, comparada con la de otros metodos

    Energy Technology Data Exchange (ETDEWEB)

    Steyn, J [National Physical Research Laboratory, Pretoria (South Africa)

    1960-06-15

    The accuracy of the 4 {pi} liquid scintillation counting method of standardizing {beta} emitters was compared to 4 l{pi} {beta}-{gamma} coincidence counting for the nuclides Co{sup 60}, I{sup 131} and Au{sup 198}. For P{sup 32} the liquid counting results were compared to 4 {pi} proportional counting. The efficiency of the liquid scintillation counting method was found to be energy dependent, dropping to about 97.5% for Co{sup 60} which was the lowest energy {beta} emitter investigated. (author) [French] La precision de la methode de comptage 4 {pi} a scintillateurs liquides pour l'etalonnage des emetteurs {beta} a ete comparee au comptage par coincidences 4 {pi} {beta}-{gamma} pour le So{sup 60}, le I{sup 131} et le Au{sup 198}. Dans le cas du P{sup 32}, les resultats du comptage au liquide ont ete compares a ceux du comptage 4 {pi} proportionnel. On a constate que le rendement de la methode de comptage a scintillateurs liquides variait en fonction de l'energie emise et qu'il descendait a environ 97.5% pour le Co{sup 60} qui, de tous les emetteurs {beta} etudies, emet l'energie la plus faible. (author) [Spanish] El autor compara la precision del metodo de recuento con centelleador iquido 4 {pi} para normalizar emisores {beta} con la del metodo de coincidencias {beta}-{gamma} 4 {pi}, para los siguientes nuclidos: So{sup 60}, I{sup 131} y Au{sup 198}. En el caso del P{sup 32}, confronta los resultados del primer metodo con los obtenidos mediante el recuento proporcional 4 {pi}. Comprueba que la eficacia del metodo de recuento con centelleador liquido depende de la energia y desciende al 97.5%, aproximadamente, para el Co{sup 60}, que fue el emisor {beta} mas debil que se investigo. (author) [Russian] Tochnost' 4 {pi} zhidkogo stsintillyatsionnog o metoda podscheta standartiziruemogo {beta}-izluchatelya sravnivalas' s 4 {pi} {beta}-{gamma} metodom podscheta na sovpadeniyakh dlya izotopov So{sup 60}, I{sup 131} i Au{sup 198}. Dlya R{sup 32} rezultaty zhidkogo

  7. White noise of Nb-based microwave superconducting quantum interference device multiplexers with NbN coplanar resonators for readout of transition edge sensors

    Science.gov (United States)

    Kohjiro, Satoshi; Hirayama, Fuminori; Yamamori, Hirotake; Nagasawa, Shuichi; Fukuda, Daiji; Hidaka, Mutsuo

    2014-06-01

    White noise of dissipationless microwave radio frequency superconducting quantum interference device (RF-SQUID) multiplexers has been experimentally studied to evaluate their readout performance for transition edge sensor (TES) photon counters ranging from near infrared to gamma ray. The characterization has been carried out at 4 K, first to avoid the low-frequency fluctuations present at around 0.1 K, and second, for a feasibility study of readout operation at 4 K for extended applications. To increase the resonant Q at 4 K and maintain low noise SQUID operation, multiplexer chips consisting of niobium nitride (NbN)-based coplanar-waveguide resonators and niobium (Nb)-based RF-SQUIDs have been developed. This hybrid multiplexer exhibited 1 × 104 ≤ Q ≤ 2 × 104 and the square root of spectral density of current noise referred to the SQUID input √SI = 31 pA/√Hz. The former and the latter are factor-of-five and seven improvements from our previous results on Nb-based resonators, respectively. Two-directional readout on the complex plane of the transmission component of scattering matrix S21 enables us to distinguish the flux noise from noise originating from other sources, such as the cryogenic high electron mobility transistor (HEMT) amplifier. Systematic noise measurements with various microwave readout powers PMR make it possible to distinguish the contribution of noise sources within the system as follows: (1) The achieved √SI is dominated by the Nyquist noise from a resistor at 4 K in parallel to the SQUID input coil which is present to prevent microwave leakage to the TES. (2) The next dominant source is either the HEMT-amplifier noise (for small values of PMR) or the quantization noise due to the resolution of 300-K electronics (for large values of PMR). By a decrease of these noise levels to a degree that is achievable by current technology, we predict that the microwave RF-SQUID multiplexer can exhibit √SI ≤ 5 pA/√Hz, i.e., close to √SI of

  8. White noise of Nb-based microwave superconducting quantum interference device multiplexers with NbN coplanar resonators for readout of transition edge sensors

    International Nuclear Information System (INIS)

    Kohjiro, Satoshi; Hirayama, Fuminori; Yamamori, Hirotake; Nagasawa, Shuichi; Fukuda, Daiji; Hidaka, Mutsuo

    2014-01-01

    White noise of dissipationless microwave radio frequency superconducting quantum interference device (RF-SQUID) multiplexers has been experimentally studied to evaluate their readout performance for transition edge sensor (TES) photon counters ranging from near infrared to gamma ray. The characterization has been carried out at 4 K, first to avoid the low-frequency fluctuations present at around 0.1 K, and second, for a feasibility study of readout operation at 4 K for extended applications. To increase the resonant Q at 4 K and maintain low noise SQUID operation, multiplexer chips consisting of niobium nitride (NbN)-based coplanar-waveguide resonators and niobium (Nb)-based RF-SQUIDs have been developed. This hybrid multiplexer exhibited 1 × 10 4  ≤ Q ≤ 2 × 10 4 and the square root of spectral density of current noise referred to the SQUID input √S I  = 31 pA/√Hz. The former and the latter are factor-of-five and seven improvements from our previous results on Nb-based resonators, respectively. Two-directional readout on the complex plane of the transmission component of scattering matrix S 21 enables us to distinguish the flux noise from noise originating from other sources, such as the cryogenic high electron mobility transistor (HEMT) amplifier. Systematic noise measurements with various microwave readout powers P MR make it possible to distinguish the contribution of noise sources within the system as follows: (1) The achieved √S I is dominated by the Nyquist noise from a resistor at 4 K in parallel to the SQUID input coil which is present to prevent microwave leakage to the TES. (2) The next dominant source is either the HEMT-amplifier noise (for small values of P MR ) or the quantization noise due to the resolution of 300-K electronics (for large values of P MR ). By a decrease of these noise levels to a degree that is achievable by current technology, we predict that the microwave RF-SQUID multiplexer can exhibit

  9. TH-EF-BRB-03: Significant Cord and Esophagus Dose Reduction by 4π Non-Coplanar Spine Stereotactic Body Radiation Therapy and Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Yu, V; Tran, A; Nguyen, D; Woods, K; Cao, M; Kaprealian, T; Chin, R; Low, D; Sheng, K [UCLA, Los Angeles, CA (United States)

    2016-06-15

    Purpose: To demonstrate significant organ-at-risk (OAR) sparing achievable with 4π non-coplanar radiotherapy on spine SBRT and SRS patients. Methods: Twenty-five stereotactic spine cases previously treated with VMAT (n = 23) or IMRT (n = 2) were included in this study. A computer-aided-design model of a Linac with a 3D-scanned human surface was utilized to determine the feasible beam space throughout the 4π steradian and beam specific source-to-target-distances (STD) required for collision avoidance. 4π radiotherapy plans integrating beam orientation and fluence map optimization were then created using a column-generation algorithm. Twenty optimal beams were selected for each case. To evaluate the tradeoff between dosimetric benefit and treatment complexity, 4π plans including only isocentrically deliverable beams were also created. Beam angles of all standard and isocentric 4π plans were imported into Eclipse to recalculate the dose using the same calculation engine as the clinical plans for unbiased comparison. OAR and PTV dose statistics for the clinical, standard-4π, and isocentric-4π plans were compared. Results: Comparing standard-4π to clinical plans, particularly significant average percent reduction in the [mean, maximum] dose of the cord and esophagus of [41%, 21.7%], and [38.7%, 36.4%] was observed, along with global decrease in all other OAR dose statistics. The average cord volume receiving more than 50% prescription dose was substantially decreased by 76%. In addition, improved PTV coverage was demonstrated with a maximum dose reduction of 0.93% and 1.66% increase in homogeneity index (D95/D5). All isocentric-4π plans achieved dosimetric performance equivalent to that of the standard-4π plans with higher delivery complexity. Conclusion: 4π radiotherapy significantly improves stereotactic spine treatment dosimetry. With the substantial OAR dose sparing, PTV dose escalation is considerably safer. Isocentric-4π is sufficient to achieve the

  10. Channel-closing effects in strong-field ionization by a bicircular field

    Science.gov (United States)

    Milošević, D. B.; Becker, W.

    2018-03-01

    Channel-closing effects, such as threshold anomalies and resonantlike intensity-dependent enhancements in strong-field ionization by a bicircular laser field are analyzed. A bicircular field consists of two coplanar corotating or counter-rotating circularly polarized fields having different frequencies. For the total detachment rate of a negative ion by a bicircular field we observe threshold anomalies and explain them using the Wigner threshold law and energy and angular momentum conservation. For the corotating bicircular case, these effects are negligible, while for the counter-rotating case they are pronounced and their position depends on the magnetic quantum number of the initial state. For high-order above-threshold ionization of rare-gas atoms by a counter-rotating bicircular laser field we observe very pronounced intensity-dependent enhancements. We find all four types of threshold anomalies known from collision theory. Contrary to the case of linear polarization, channel-closing effects for a bicircular field are visible also in the cutoff region of the electron energy spectrum, which is explained using quantum-orbit theory.

  11. Pipeline integrity management using Monte Carlo simulation; A aplicacao do metodo de Monte Carlo no gerenciamento da integridade de dutos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Claudio; Costa, Artur; Bittencourt, Euclides [TRANSPETRO - PETROBRAS Transporte, Rio de Janeiro, RJ (Brazil)

    2005-07-01

    Due to the growing relevance of safety and environmental protection policies in PETROBRAS and its subsidiaries, as well as official regulatory agencies and population requirements, integrity management of oil and gas pipelines became a priority activity in TRANSPETRO, involving several sectors of the company's Support Management Department. Inspection activities using intelligent PIGs, field correlations and replacement of pipeline segments are known as high cost operations and request complex logistics. Thus, it is imperative the adoption of management tools that optimize the available resources. This study presents Monte Carlo simulation method as an additional tool for evaluation and management of pipeline structural integrity. The method consists in foreseeing future physical conditions of most significant defects found in intelligent PIG In Line Inspections based on a probabilistic approach. Through Monte Carlo simulation, probability functions of failure for each defect are produced, helping managers to decide which repairs should be executed in order to reach the desired or accepted risk level. The case that illustrates this study refers to the reconditioning of ORSOL 14'' (35,56 mm) pipeline. This pipeline was constructed to transfer petroleum from Urucu's production fields to Solimoes port, in Coari, city in Brazilian Amazon Region. The result of this analysis indicated critical points for repair, in addition to the results obtained by the conventional evaluation (deterministic ASME B-31G method). Due to the difficulties to mobilize staff and execute necessary repairs in remote areas like Amazon forest, the probabilistic tool was extremely useful, improving pipeline integrity level and avoiding future additional costs. (author)

  12. Modern analytic methods applied to the art and archaeology; Metodos analiticos modernos aplicados al arte y la arqueologia

    Energy Technology Data Exchange (ETDEWEB)

    Tenorio C, M. D.; Longoria G, L. C., E-mail: dolores.tenorio@inin.gob.m [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-07-01

    The interaction of diverse areas as the analytic chemistry, the history of the art and the archaeology has allowed the development of a variety of techniques used in archaeology, in conservation and restoration. These methods have been used to date objects, to determine the origin of the old materials and to reconstruct their use and to identify the degradation processes that affect the integrity of the art works. The objective of this chapter is to offer a general vision on the researches that have been realized in the Instituto Nacional de Investigaciones Nucleares (ININ) in the field of cultural goods. A series of researches carried out in collaboration with national investigators and of the foreigner is described shortly, as well as with the great support of degree students and master in archaeology of the National School of Anthropology and History, since one of the goals that have is to diffuse the knowledge of the existence of these techniques among the young archaeologists, so that they have a wider vision of what they could use in an in mediate future and they can check hypothesis with scientific methods. (Author)

  13. Influence of the drying method in chitosans purification step; Influencia do metodo de secagem na etapa de purificacao de quitosanas

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Ana C.M.; Batista, Jorge G.S.; Bettega, Antonio; Lima, Nelson B. de, E-mail: acmfonseca.acf@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Currently, the study of extracellular biopolymers properties has received prominence for being easy extraction and purification. Chitosan has been an attractive proposition for applications in various fields such as engineering, biotechnology, medicine and pharmacology. For such applications, it is necessary purification of chitosan to obtain a product more concentrated and free of undesirable impurities. However, at this stage of the process of obtaining the biopolymer may occur morphological and physicochemical changes. This study evaluated the influence of the drying process after purification of a commercial chitosan sample and the importance of this step and its cost/benefit in applications requiring a high degree of purity. The method of drying influenced in the organoleptic properties and in the main characteristics of material. Analysis of the crystal structure by X-ray diffraction showed that the degree of crystallinity, X (%), in the purified chitosan samples was lower when compared with the unpurified sample. The degree of acetylation, DA (%), was analyzed by spectroscopy infrared with no significant changes on the three drying methods assessed, unlike the viscosimetric molecular weight, M{sub v}, determined by capillary viscometry. (author)

  14. The Brazilian dilution method for ballast water exchange; O metodo de diluicao brasileiro para troca de agua de lastro

    Energy Technology Data Exchange (ETDEWEB)

    Mauro, Celso Alleluia [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Avaliacao e Monitoramento Ambiental]. E-mail: celso@cenpes.petrobras.com.br; Land, Claudio Goncalves [PETROBRAS, Rio de Janeiro, RJ (Brazil). Abastecimento, Logistica e Planejamento]. E-mail: cgland@petrobras.com.br; Pimenta, Jose Maria Hollanda Alvares; Barreto, Francisco Carlos Peixoto [PETROBRAS, Rio de Janeiro, RJ (Brazil). Engenharia; Brandao, Marcus Vinicius Lisboa; Marroig, Nilton Lemos [Transpetro, Rio de Janeiro, RJ (Brazil). Frota Nacional de Petroleiros. Inspetoria Geral; Tristao, Maria Luiza Braganca [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Quimica; Fadel, Andre Luiz da Fonseca [PETROBRAS, Rio de Janeiro, RJ (Brazil). Financas Corporativa e Tesouraria; Villac, Maria Celia; Fernandes, Lohengrin; Paranhos, Rodolfo; Dias, Cristina; Bonecker, Sergio; Denise Tenenbaum [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Biologia; Persich, Graziela; Garcia, Virginia; Odebrecht, Clarisse [Fundacao Universidade do Rio Grande, RS (Brazil). Dept. de Oceanografia

    2002-12-01

    In a precautionary approach and dealing with the coming International Maritime Organization (IMO) regulations on ballast water, PETROBRAS developed a new method for ballast water exchange in tankers. Differently from ordinary methods PETROBRAS method which have been called Brazilian Dilution Method (BDM) or Dilution Method involves ballast loading through the top with simultaneous unloading from the bottom of the tanks. The method proposal was firstly presented to IMO, which encouraged PETROBRAS to carry out a field trial. PETROBRAS in June 1998 carried out a trial in the product carrier M/V Lavras. A simulation study was useful to plan the trial assessing the theoretical efficiency of the method, establishing the best sampling points and comparing the BDM with the Tank Overfilling Method (TOM). Simulation showed that for the same tank shape, the water renewal in BDM is more effective than in TOM and that 90 % of water renewal could be obtained by BDM. A dye concentration variation monitoring and a biological assessment were performed and the results confirmed that over than 90 % of the ballast water was renewed after three exchanges. The method was proved safe, practical, economical and suitable to minimize the risk of exotic species transport between ports. (author)

  15. Some Non-Destructive Testing Methods Applicable to Sintered Materials; Quelques Methodes d'Essais Non Destructifs Applicables aux Materiaux Frittes; Nekotorye metody nedestruktivnykh ispytanii, primenimye k spechennym materialam; Algunos Metodos de Ensayo No Destructivo Aplicables a los Materiales Sinterizados

    Energy Technology Data Exchange (ETDEWEB)

    Labusca, Elena; Mirion, I.; Andreescu, N.; Alecu, M.; Biscoveanu, I. [Institut de Physique Atomique, Bucarest (Romania)

    1965-10-15

    solides frittes, a l'aide de la metallographie et de la microscopie electronique. Ces methodes mettent en evidence l'homogeneite de la structure, les dimensions et l'orientation des grains, la presence de defauts divers (inclusions, pores) et revolution meme du processus de frittage, y compris la formation des cristaux, la croissance granulaire, etc. Dans quelques cas, on peut combiner l'examen microscopique a des essais de microdurete. Cet examen de la structure microcristalline represente l'une des methodes principales de controle qualitatif des materiaux frittes, et ne peut etre remplace par aucun autre moyen d'investigation. 2. Controle du degre de consolidation, qui determine essentiellement la qualite des materiaux frittes. Ce controle est effectue par la mesure de quelques proprietes, telles que la conductibilite electrique et thermique, en correlation avec la densite, etant donne que la conductibilite des materiaux frittes est directement porportionnelle au degre de frittage. On a essaye aussi une methode adequate de controle de la porosite; on a obtenu des donnees experimentales interessantes, surtout au point de vue de la porosite libre, laquelle est susceptible aux inclusions gazeuses. Le memoire contient des donnees experimentales concernant l'application de ces methodes de controle a quelques materiaux frittes interessants pour la technologie nucleaire. (author) [Spanish] Teniendo en cuenta la estructura granular especifica de los materiales sinterizados, elaborados a partir de polvos, cuyo proceso de consolidacion se desarrolla en funcion del tratamiento de sinterizacion, los autores han estudiado algunos metodos para verificar el grado de sinterizacion y controlar ciertas propiedades. Entre los metodos no destructivos utilizados, se mencionan en la presente memoria: 1. Examen de la estructura cristalina de los solidos sinterizados por metalografia y microscopfa electronica. Estos metodos ponen de manifiesto el giado de homogeneidad estructural, la dimension

  16. The relative biological effectiveness of out-of-field dose

    International Nuclear Information System (INIS)

    Balderson, Michael; Koger, Brandon; Kirkby, Charles

    2016-01-01

    Purpose: using simulations and models derived from existing literature, this work investigates relative biological effectiveness (RBE) for out-of-field radiation and attempts to quantify the relative magnitudes of different contributing phenomena (spectral, bystander, and low dose hypersensitivity effects). Specific attention is paid to external beam radiotherapy treatments for prostate cancer. Materials and methods: using different biological models that account for spectral, bystander, and low dose hypersensitivity effects, the RBE was calculated for different points moving radially out from isocentre for a typical single arc VMAT prostate case. The RBE was found by taking the ratio of the equivalent dose with the physical dose. Equivalent doses were calculated by determining what physical dose would be necessary to produce the same overall biological effect as that predicted using the different biological models. Results: spectral effects changed the RBE out-of-field less than 2%, whereas response models incorporating low dose hypersensitivity and bystander effects resulted in a much more profound change of the RBE for out-of-field doses. The bystander effect had the largest RBE for points located just outside the edge of the primary radiation beam in the cranial caudal (z-direction) compared to low dose hypersensitivity and spectral effects. In the coplanar direction, bystander effect played the largest role in enhancing the RBE for points up to 8.75 cm from isocentre. Conclusions: spectral, bystander, and low dose hypersensitivity effects can all increase the RBE for out-of-field radiation doses. In most cases, bystander effects seem to play the largest role followed by low dose hypersensitivity. Spectral effects were unlikely to be of any clinical significance. Bystander, low dose hypersensitivity, and spectral effect increased the RBE much more in the cranial caudal direction (z-direction) compared with the coplanar directions. (paper)

  17. Factors application of MW-mile method and participation in the allocation of charges by the drills use in electricity markets; Aplicacion de los factores de participacion y del metodo de MW-milla en la asignacion de cargos por uso de redes de transmision en mercados de electricidad

    Energy Technology Data Exchange (ETDEWEB)

    Alba-Gomez, L; Tovar-Hernandez, J. H; Gutierrez-Alcaraz, G [Instituto Tecnologico de Morelia, Michoacan (Mexico)]. E-mail: horaciotovar@mexico.com; ggutier@itmorelia.edu.mx

    2007-04-15

    Use of network allocation costs by shift factors and MW-Mile method is reported in this paper. Conventional shift factors are computed based on DC power flow. DC power flow requires to selecting a slack bus in order to avoid matrix singularity. Therefore, shift factors are slack bus dependent. In order to evade slack bus dependency, two approaches are considered. [Spanish] Este trabajo presenta la asignacion de costos por uso de red mediante la aplicacion de Factores de Participacion (FP) y el metodo de MW-Milla. Los FP clasicos son calculados a partir del modelo lineal de flujos de potencia para lo que se requiere de establecer un nodo de referencia a fin de eliminar la singularidad de la matriz de coeficientes. Por lo tanto, los FP son dependientes de la asignacion del nodo de referencia. Dos metodos alternativos para evitar la dependencia del nodo compensador en la obtencion de los factores de participacion son presentados.

  18. Initial temperature distribution in Los Humeros, Mexico, geothermal field; Distribucion de temperatura inicial en el campo geotermico de Los Humeros, Puebla

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, A; Arellano, V; Aragon, A; Barragan, R.M; Izquierdo, G [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico); Pizano, A [Comision federal de Electricidad, Los Humeros, Puebla (Mexico)

    2000-12-01

    The initial formation temperatures surrounding 40 wells from the Los Humeros geothermal field are presented. These temperatures were estimated using the Horner and the sphere methods. A brief discussion on the applicability of each method is presented and previous applications are detailed. Then the more likely reservoir temperature of each well versus elevation is plotted based on the estimations about the main feed zone and the temperature of each well. The boiling with depth curve for pure water is also included. Two longitudinal and one traverse geological sections are presented to illustrate the field initial temperature distribution, the lithology and layers thickness, the basement topography and the wells traversed along each sections. Also, the main feed zones of the wells are indicated. Finally, the last series of measured temperature logs in well H-26 are produced by numerical simulation. This considers the well circulation losses and an assumed initial temperature profile. This profile iteratively modified until the computed profiles match the measured temperature profiles. The last assumed temperature profile is then considered as the best approximation to the undisturbed formation temperature around well H-26 and it is then compared with the stabilized temperatures obtained via the Horner and Sphere methods. [Spanish] Se presentan las temperaturas iniciales o estabilizadas de la formacion circundante a 40 pozos del campo geotermico Los Humeros, las cuales se estimaron mediante los metodos de Horner y el metodo de la esfera. Se presenta una discusion sobre la aplicacion de cada metodo y se detallan las aplicaciones previas del metodo de la esfera. Posteriormente y con base en las estimaciones de las principales zonas de aporte de cada pozo y sus correspondientes temperaturas se grafican las temperaturas mas probables de yacimiento para cada pozo contra la elevacion y se incluye en la misma grafica la curva de ebullicion del agua contra la elevacion. Se

  19. Noncoplanar magnetic fields at collisionless shocks: A test of a new approach

    International Nuclear Information System (INIS)

    Gosling, J.T.; Winske, D.; Thomsen, M.F.

    1988-01-01

    Within the foot and ramp of a fast mode collisionless shock the magnetic field rotates out of the plane of coplanarity defined by the upstream magnetic field and the shock normal. As previously noted (Goodrich and Scudder, 1984), the sense of this rotation is such as to reduce the cross-shock potential drop when measured in the deHoffman-Teller frame relative to that measured in the normal incidence frame. From a consideration of the requirement that there be zero current in the coplanarity plane downstream of the shock, Jones and Ellison (1987) have argued that the field rotation and potential drop difference are a consequence of unequal ion and electron masses, and have derived an expression for the spatial integral of the noncoplanar field component in terms of the electron current within the shock layer. Moreover, by assuming that the ion current within the shock layer is negligible compared to the electron current, they derive equations which predict the magnitude of both the field rotation and the potential drop difference in terms of upstream quantities and the field jump at the shock. We have tested their equations with ISEE 1 and 2 plasma and field measurements at the Earth's bow shock and by means of numerical simulations. We find substantial support for their suggestion that the field rotation and thus also the frame dependence of the potential drop are fundamentally a consequence of unequal ion and electron masses. Further, for subcritical shocks (low Mach number) one can neglect the ion current to predict both the sign and the magnitude of the field rotation and potential drop difference. However, at supercritical shocks (high Mach numbers) the ion current associated with reflected, gyrating ions cannot be neglected, and the final equations of Jones and Ellison seriously underestimate the magnitude of the field rotation and the potential drop difference at these shocks

  20. Strong-field ionization of linear molecules by a bicircular laser field: Symmetry considerations

    Science.gov (United States)

    Gazibegović-Busuladžić, A.; Busuladžić, M.; Hasović, E.; Becker, W.; Milošević, D. B.

    2018-04-01

    Using the improved molecular strong-field approximation, we investigate (high-order) above-threshold ionization [(H)ATI] of various linear polyatomic molecules by a two-color laser field of frequencies r ω and s ω (with integer numbers r and s ) having coplanar counter-rotating circularly polarized components (a so-called bicircular field). Reflection and rotational symmetries for molecules aligned in the laser-field polarization plane, analyzed for diatomic homonuclear molecules in Phys. Rev. A 95, 033411 (2017), 10.1103/PhysRevA.95.033411, are now considered for diatomic heteronuclear molecules and symmetric and asymmetric linear triatomic molecules. There are additional rotational symmetries for (H)ATI spectra of symmetric linear molecules compared to (H)ATI spectra of the asymmetric ones. It is shown that these symmetries manifest themselves differently for r +s odd and r +s even. For example, HATI spectra for symmetric molecules with r +s even obey inversion symmetry. For ATI spectra of linear molecules, reflection symmetry appears only for certain molecular orientation angles ±90∘-j r 180∘/(r +s ) (j integer). For symmetric linear molecules, reflection symmetry appears also for the angles -j r 180∘/(r +s ) . For perpendicular orientation of molecules with respect to the laser-field polarization plane, the HATI spectra are very similar to those of the atomic targets, i.e., both spectra are characterized by the same type of the (r +s )-fold symmetry.

  1. Effect of magnetic field on noncollinear magnetism in classical bilinear-biquadratic Heisenberg model

    Energy Technology Data Exchange (ETDEWEB)

    Pasrija, Kanika, E-mail: kanikapasrija@iisermohali.ac.in; Kumar, Sanjeev, E-mail: sanjeev@iisermohali.ac.in [Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, S. A. S. Nagar, Manauli PO 140306 (India)

    2016-05-06

    We present a Monte Carlo simulation study of a bilinear-biquadratic Heisenberg model on a two-dimensional square lattice in the presence of an external magnetic field. The study is motivated by the relevance of this simple model to the non-collinear magnetism and the consequent ferroelectric behavior in the recently discovered high-temperature multiferroic, cupric oxide (CuO). We show that an external magnetic field stabilizes a non-coplanar magnetic phase, which is characterized by a finite ferromagnetic moment along the direction of the applied magnetic field and a spiral spin texture if projected in the plane perpendicular to the magnetic field. Real-space analysis highlights a coexistence of non-collinear regions with ferromagnetic clusters. The results are also supported by simple variational calculations.

  2. Micromachined silicon cantilevers with integrated high-frequency magnetoimpedance sensors for simultaneous strain and magnetic field detection

    Science.gov (United States)

    Buettel, G.; Joppich, J.; Hartmann, U.

    2017-12-01

    Giant magnetoimpedance (GMI) measurements in the high-frequency regime utilizing a coplanar waveguide with an integrated Permalloy multilayer and micromachined on a silicon cantilever are reported. The fabrication process is described in detail. The aspect ratio of the magnetic multilayer in the magnetoresistive and magnetostrictive device was varied. Tensile strain and compressive strain were applied. Vector network analyzer measurements in the range from the skin effect to ferromagnetic resonance confirm the technological potential of GMI-based micro-electro-mechanical devices for strain and magnetic field sensing applications. The strain-impedance gauge factor was quantified by finite element strain calculations and reaches a maximum value of almost 200.

  3. Gas geochemistry of Los Humeros geothermal field, Mexico; Geoquimica de gases del campo geotermico de Los Humeros, Puebla, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Barragan R, Rosa Maria; Arellano G, Victor M; Nieva G, David; Portugal M, Enrique; Garcia G, Alfonso; Aragon A, Alfonso [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico); Torres A, Ignasio S [Centro de Investigacion en Energia, Temixco, Morelos (Mexico); Tovar A, Rigoberto [Comision Federal de Electricidad, Los Humeros, Puebla (Mexico)

    1999-12-01

    Gas data of Los Humeros geothermal field were analyzed. A new method, which is based on the Fischer-Tropch reactions and on the combined pyrite-magnetite mineral equilibrium, was used. Reservoir temperature and reservoir excess steam were estimated for the starting stage of the field by using early data taken from producing wells at controlled conditions. The same parameters were also obtained for the present stage by using 1997 gas data. Reservoir temperatures ranged from 275 and 337 Celsius degrees and positive values for reservoir excess steam fractions were obtained for the starting stage. For well H-1 no excess steam was found since this well was fed by the shallower liquid-dominated reservoir. Results for 1997 showed lower scattering compared to early data and the possible occurrence of a heating process in the shallower stratum which could due to exploitation. [Spanish] En este articulo se presenta un analisis de datos de la fase gaseosa producida por pozos productores del campo geotermico de Los Humeros mediante un metodo que considera el equilibrio de la reaccion de Fischer-Tropsh y el equilibrio de minerales pirita-hematia y pirita-magnetita. Este metodo provee la temperatura del yacimiento y el exceso de vapor presente en la descarga total de los pozos. Los resultados se discuten tanto para el estado inicial del yacimiento utilizando los primeros datos de produccion en los que el flujo del pozo estuvo controlado y los obtenidos en 1997 que representan el estado actual del yacimiento. En el estado inicial se estimaron temperaturas de yacimiento de entre 275 y 337 grados Celsius y excesos de vapor positivos, con excepcion del pozo H-1 que se alimenta del estrato somero dominado por liquido. Los resultados obtenidos para 1997 muestran una dispersion menor y la probable ocurrencia de un proceso de calentamiento del estrato somero propiciado por la explotacion.

  4. Effects of the reconnection electric field on crescent electron distribution functions in asymmetric guide field reconnection

    Science.gov (United States)

    Bessho, N.; Chen, L. J.; Hesse, M.; Wang, S.

    2017-12-01

    In asymmetric reconnection with a guide field in the Earth's magnetopause, electron motion in the electron diffusion region (EDR) is largely affected by the guide field, the Hall electric field, and the reconnection electric field. The electron motion in the EDR is neither simple gyration around the guide field nor simple meandering motion across the current sheet. The combined meandering motion and gyration has essential effects on particle acceleration by the in-plane Hall electric field (existing only in the magnetospheric side) and the out-of-plane reconnection electric field. We analyze electron motion and crescent-shaped electron distribution functions in the EDR in asymmetric guide field reconnection, and perform 2-D particle-in-cell (PIC) simulations to elucidate the effect of reconnection electric field on electron distribution functions. Recently, we have analytically expressed the acceleration effect due to the reconnection electric field on electron crescent distribution functions in asymmetric reconnection without a guide field (Bessho et al., Phys. Plasmas, 24, 072903, 2017). We extend the theory to asymmetric guide field reconnection, and predict the crescent bulge in distribution functions. Assuming 1D approximation of field variations in the EDR, we derive the time period of oscillatory electron motion (meandering + gyration) in the EDR. The time period is expressed as a hybrid of the meandering period and the gyro period. Due to the guide field, electrons not only oscillate along crescent-shaped trajectories in the velocity plane perpendicular to the antiparallel magnetic fields, but also move along parabolic trajectories in the velocity plane coplanar with magnetic field. The trajectory in the velocity space gradually shifts to the acceleration direction by the reconnection electric field as multiple bounces continue. Due to the guide field, electron distributions for meandering particles are bounded by two paraboloids (or hyperboloids) in the

  5. Cluster magnetic field observations of the bowshock: Orientation, motion and structure

    Directory of Open Access Journals (Sweden)

    T. S. Horbury

    Full Text Available Four spacecraft Cluster magnetic field observations of the low quasi-perpendicular terrestrial bowshock are presented for the first time. Multiple quasi-perpendicular crossings on 25 December 2000 are analysed. By combining data from the four spacecraft, bowshock orientations and velocities can be calculated. It is shown that, even while in rapid motion, the bowshock normal direction remains remarkably constant, and that coplanarity estimates are accurate to, typically, around 20°. Magnetic field magnitude profiles are shown to be very well correlated between spacecraft although downstream waves with fluctuations perpendicular to the local field, while statistically similar at all four spacecraft, are poorly correlated on separation scales of several hundred km. Examples are shown of a number of bowshock phenomena, including non-standing fluctuations in the shock foot and the shock interacting with changing solar wind conditions.

    Key words. Interplanetary physics (planetary bow shocks Space plasma physics (shock waves; waves and instabilities

  6. Cluster magnetic field observations of the bowshock: Orientation, motion and structure

    Directory of Open Access Journals (Sweden)

    T. S. Horbury

    2001-09-01

    Full Text Available Four spacecraft Cluster magnetic field observations of the low quasi-perpendicular terrestrial bowshock are presented for the first time. Multiple quasi-perpendicular crossings on 25 December 2000 are analysed. By combining data from the four spacecraft, bowshock orientations and velocities can be calculated. It is shown that, even while in rapid motion, the bowshock normal direction remains remarkably constant, and that coplanarity estimates are accurate to, typically, around 20°. Magnetic field magnitude profiles are shown to be very well correlated between spacecraft although downstream waves with fluctuations perpendicular to the local field, while statistically similar at all four spacecraft, are poorly correlated on separation scales of several hundred km. Examples are shown of a number of bowshock phenomena, including non-standing fluctuations in the shock foot and the shock interacting with changing solar wind conditions.Key words. Interplanetary physics (planetary bow shocks Space plasma physics (shock waves; waves and instabilities

  7. Low-power-consumption and high-sensitivity NO2 micro gas sensors based on a co-planar micro-heater fabricated by using a CMOS-MEMS process

    International Nuclear Information System (INIS)

    Moon, S. E.; Lee, J. W.; Park, S. J.; Park, J.; Park, K. H.; Kim, J.

    2010-01-01

    Small-scale, low-power-consumption, and high-sensitivity NO 2 gas sensors based on ZnO nanorods are reported in this work. To activate the chemical absorption and desorption for NO 2 gas, we embedded co-planar micro-heater in a micro gas sensor, that was made by using a Complementary Metal-oxide-semiconductor compatible Microelectromechanical Systems(CMOS-MEMS) process. To acquire simple fabrication and low fabrication cost, we located the micro-heater and the sensing electrode in the same plane. High-quality single-crystalline ZnO nanorods were selectively grown by using photolithography and a hydrothermal method. Their structural properties were confirmed by using X-ray diffractometry (XRD), energy dispersive X-ray spectroscopy microanalysis (EDAX), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The temperature-dependent current-voltage characteristics were measured to optimize the operating temperature of the fabricated devices as a chemical gas sensor. To test the possibility for use as chemical sensor, we measured the NO 2 gas response.

  8. A 40 GHz fully integrated circuit with a vector network analyzer and a coplanar-line-based detection area for circulating tumor cell analysis using 65 nm CMOS technology

    Science.gov (United States)

    Nakanishi, Taiki; Matsunaga, Maya; Kobayashi, Atsuki; Nakazato, Kazuo; Niitsu, Kiichi

    2018-03-01

    A 40-GHz fully integrated CMOS-based circuit for circulating tumor cells (CTC) analysis, consisting of an on-chip vector network analyzer (VNA) and a highly sensitive coplanar-line-based detection area is presented in this paper. In this work, we introduce a fully integrated architecture that eliminates unwanted parasitic effects. The proposed analyzer was designed using 65 nm CMOS technology, and SPICE and MWS simulations were used to validate its operation. The simulation confirmed that the proposed circuit can measure S-parameter shifts resulting from the addition of various types of tumor cells to the detection area, the data of which are provided in a previous study: the |S 21| values for HepG2, A549, and HEC-1-A cells are -0.683, -0.580, and -0.623 dB, respectively. Additionally, the measurement demonstrated an S-parameters reduction of -25.7% when a silicone resin was put on the circuit. Hence, the proposed system is expected to contribute to cancer diagnosis.

  9. Electric field measurements at subcritical, oblique bow shock crossings

    International Nuclear Information System (INIS)

    Wygant, J.R.; Bensadoun, M.; Mozer, F.S.

    1987-01-01

    Electric field measurements at oblique, subcritical bow shock crossings are presented from the ISEE 1 University of California, Berkeley, double-probe electric field experiment. The measurements averaged over the 3-s spin period of the spacecraft provide the first observations of the large-scale (100 km) laminar oscillations in the longitudinal component of the electric field associated with the whistler precursor which is characteristic of these dispersive shocks. The amplitude of the oscillations increases from ∼0.5 mV/m to a maximum of 6 mV/m across the magnetic ramp of the shock (directed along the shock normal). The calculated electric potential drops across the shocks varied from 340 to 550 volts, which is 40-60% of the observed loss of kinetic energy associated with the bulk flow of the ions. These measurements suggest that at these shocks the additional deceleration of incident ions is due to the Lorentz force. The contributions to the normal component of the large-scale electric field at the shock due to the parallel and perpendicular components (relative to the magnetic field) of the electric field are evaluated. It is shown that the perpendicular component of the electric field dominates, accounting for most of the cross-shock potential, but that there is a nonnegligible parallel component. This large-scale parallel component has a magnitude of 1-2 mV/m which sometimes results in a potential well for electrons with a depth of ∼150 eV. It is experimentally demonstrated that the dominance of the perpendicular over the parallel component of the electric field resulted in a correlation between the longitudinal component of the large-scale electric field and the fluctuations in the magnetic field component perpendicular to the coplanarity plane

  10. Quantum incommensurate skyrmion crystals and commensurate to in-commensurate transitions in cold atoms and materials with spin-orbit couplings in a Zeeman field

    Science.gov (United States)

    Sun, Fadi; Ye, Jinwu; Liu, Wu-Ming

    2017-08-01

    In this work, we study strongly interacting spinor atoms in a lattice subject to a two dimensional (2d) anisotropic Rashba type of spin orbital coupling (SOC) and an Zeeman field. We find the interplay between the Zeeman field and the SOC provides a new platform to host rich and novel classes of quantum commensurate and in-commensurate phases, excitations and phase transitions. These commensurate phases include two collinear states at low and high Zeeman field, two co-planar canted states at mirror reflected SOC parameters respectively. Most importantly, there are non-coplanar incommensurate Skyrmion (IC-SkX) crystal phases surrounded by the four commensurate phases. New excitation spectra above all the five phases, especially on the IC-SKX phase are computed. Three different classes of quantum commensurate to in-commensurate transitions from the IC-SKX to its four neighboring commensurate phases are identified. Finite temperature behaviors and transitions are discussed. The critical temperatures of all the phases can be raised above that reachable by current cold atom cooling techniques simply by tuning the number of atoms N per site. In view of recent impressive experimental advances in generating 2d SOC for cold atoms in optical lattices, these new many-body phenomena can be explored in the current and near future cold atom experiments. Applications to various materials such as MnSi, {Fe}}0.5 {Co}}0.5Si, especially the complex incommensurate magnetic ordering in Li2IrO3 are given.

  11. Poster — Thur Eve — 65: A dosimetric comparison of isocentric and non-isocentric coplanar SBRT VMAT plans for peripheral lung tumours

    International Nuclear Information System (INIS)

    Conroy, L; Liu, HW; Lau, H; Smith, WL

    2014-01-01

    Volumetric modulated arc therapy (VMAT) delivers lung sterotactic body radiotherapy (SBRT) in shorter treatment time and less monitor units with comparable coverage and organ at risk sparing compared to conventional SBRT treatments. Isocentric VMAT treatment of peripheral lung tumours occasionally requires couch shifts that can inhibit 360° gantry rotation, resulting in additional imaging shifts for each treatment session, and increased potential for involuntary in-fraction motion. Here, we investigate whether non-isocentric VMAT plans can achieve comparable plan quality to isocentric plans for peripheral lung tumours. Three patient plans were selected with targets displaced > 8.5 cm (range: 8.8 – 9.9 cm) laterally from patient midline. For each patient, a plan with isocentre placed within the target volume (isocentric plan) was created and optimized. The same optimization parameters were then used to create a plan with the isocentre at patient midline (non-isocentric plan). Plan quality was evaluated and compared based on planning target volume (PTV) coverage, high dose spillage, dose homogeneity, intermediate dose spillage, dose fall-off gradient, and organ at risk contraints. Non-isocentric plans of equivalent plan quality to isocentric plans were achieved for all patients by optimizing collimator rotations. Field isocentres can be placed at patient midline, as opposed to inside the target volume, with no significant degradation in VMAT plan quality for lateral tumour displacements up to 10 cm. Non-isocentric treatment of peripheral lung tumours could result in decreased overall treatment session time and eliminate the need for imaging shifts prior to VMAT treatment

  12. Development of a chromatographic method for the study of the stability and compatibility of Mexican fuel oils; Desarrollo de un metodo cromatografico para el estudio de estabilidad y compatibilidad de combustoleos mexicanos

    Energy Technology Data Exchange (ETDEWEB)

    Blass Amador, Georgina; Panama Tirado, Luz Angelica [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1992-11-01

    compatibility of fuel oil mixes. [Espanol] En Mexico, la mayoria de la energia electrica producida proviene del uso de combustibles residuales pesados conocidos como combustoleos los cuales han sufrido disminuciones en la calidad debido a una combinacion de factores, entre los que destaca el de los cambios en el proceso de refinacion. Es necesario desarrollar metodos que sean capaces de indicar la inestabilidad (formacion de sedimento o incremento en viscosidad durante el almacenamiento o calentamiento) o incompatibilidad (formacion de sedimento al mezclar dos o mas) de los combustoleos utilizados en las centrales termoelectricas. El objetivo de este trabajo fue el desarrollar una prueba alternativa para el estudio de la compatibilidad y/o estabilidad de combustoleos mexicanos empleando cromatografia de liquidos de alta resolucion (CLAR) y asi poder determinar aspectos estructurales del combustoleo que determinan su estabilidad. Dado que la formacion de sedimentos ocurre cuando el poder disolvente del combustible es inadecuado para mantener los asfaltenos en solucion, es importante conocer la medida del poder disolvente o aromaticidad del diluyente; asi pues, la primera parte de este trabajo se centro en la determinacion del perfil de compuestos aromaticos de los diluyentes de los combustoleos, la otra parte se dedico a la determinacion del perfil de distribucion de los pesos moleculares de los asfaltenos presentes en los combustoleos. Los perfiles de la fraccion aromatica, asi como los de distribucion de pesos moleculares se determinaron empleando cromatografia de liquidos, en la que se empleo una variedad de columnas y de disolventes. Se efectuo una combinacion de pruebas de rutina tales como contenido de asfaltenos, equivalencia de tolueno, viscosidad, etcetera con el fin de obtener correlaciones con el metodo cromatografico desarrollado. En este articulo se discute solo la seccion correspondiente a la obtencion del perfil de contenidos de aromaticos de los combustoleos. Se

  13. Sizing an isolated wind-solar-fuel cell generation system based on the particle swarm optimization method; Dimensionamiento de un sistema de generacion aislado eolico-solar-celda de combustible basado en el metodo de optimizacion de enjambre de particulas

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Huerta, V; Ramirez-Arredondo, Juan M. [Universidad de Quintana Roo, Chetumal, Quintana Roo (Mexico)]. E-mail: vsanchez@gdl.cinvestav.mx; Arriaga-Hurtado, L. G. [CIDETEQ, Queretaro (Mexico)

    2009-09-15

    Sizing an electric energy system requires an analysis of investment, maintenance and operating costs. In the case of a generation system that uses renewable sources, optimal capacity becomes more complex compared to a conventional system, because of the randomness of renewable resources (wind, solar) and the still high costs of wind and photovoltage generator modules. This work presents the optimal sizing of a wind-solar-fuel cell generation system, minimizing the costs of the system while satisfying the energy demands of an isolated charge. The optimization method used is based on an evolutionary programming technique known as particle swarms (PSO-particle swarm optimization). The generation of energy with a hybrid system is discussed, based on the profile of insolation and wind availability at the site, with the objective of satisfying a specific electric demand. [Spanish] El dimensionamiento de un sistema de generacion de energia electrica requiere un analisis de los costos de inversion, mantenimiento y operacion. En el caso de un sistema de generacion que utiliza fuentes renovables la capacidad optima resulta mas compleja con respecto a un sistema convencional, debido a la aleatoriedad de los recursos renovables (eolico, solar), y a los aun altos costos de generadores eolicos y modulos fotovoltaicos. En este trabajo se presenta el dimensionamiento optimo de un sistema de generacion eolico-solar-celda de combustible minimizando los costos del sistema que satisfaga la energia demandada por una carga aislada. El metodo de optimizacion utilizado esta basado en una tecnica de programacion evolutiva conocida como enjambre de particulas (PSO por sus siglas en ingles: particle swarm optimization). Se plantea la generacion de energia del sistema hibrido con base a la insolacion y el perfil del viento disponible en sitio, con objeto de satisfacer una demanda electrica determinada.

  14. A review of calculation methods for fast and intermediate reactors; Expose des methodes pour le calcul de reacteurs a neutrons rapides et intermediaires; Obzor metodov rascheta reaktorov na promezhutochnykh i bystrykh nejtronakh; Estudio panoramico de los metodos de calculo de los reactores rapidos e intermedios

    Energy Technology Data Exchange (ETDEWEB)

    Marchuk, G I [Akademiya Nauk, Moskva, Union of Soviet Socialist Republics (Russian Federation)

    1962-03-15

    This paper discusses the development of methods for calculating intermediate and fast reactors. It deals with various approaches to the problems of physical calculation. The calculation of resonance effects is discussed. Consideration is given to multi-group systems of fundamental and conjugate equations, various applications of perturbation theory to the problems of physical reactor calculation, and numerical methods of solving fundamental and conjugate reactor equations, which approximate the method of spherical harmonics. The paper describes an application of the response method to the solution of critical-mass problems, and methods of calculating reactors with hydrogeneous moderators. The fundamental features of an effective one-group reactor model are described. (author) [French] L'auteur examine la mise au point de methodes pour le calcul de reacteurs a neutrons rapides et intermediaires . Il decrit diverses manieres d'aborder les problemes des calculs sur la physique des reacteurs, notamment le calcul des effets de resonance. Il s'attache particulierement aux points suivants: systemes d'equations fondamentales et conjuguees a plusieurs groupes; diverses applications de la theorie des perturbations aux problemes de calculs sur la physique des reacteurs; methodes numeriques pour resoudre les equations fondamentales et conjuguees, voisines de la methode des harmoniques spheriques. L'auteur decrit ensuite une maniere d'appliquer la methode de la reponse aux problemes de la masse critique ainsi que des methodes pour le calcul de reacteurs ralentis a l'hydrogene. Il decrit les caracteristique s fondamentale s d'un modele de reacteur a un groupe effectif. (author) [Spanish] El autor analiza el desarrollo de los metodos de calculo de los reactores nucleares que trabajan con neutrones rapidos y con neutrones intermedios. Examina diversos planteos de los problemas del calculo fisico. Indica la forma de tomar en cuenta los efectos de resonancia y menciona los sistemas

  15. Rapid Methods of Determining Internal Radioactive Contamination; Methodes Rapides Permettant d'Evaluer la Contamination Radioactive Interne; 0411 042b 0414 ; Metodos Rapidos para Determinar la Contaminacion Radiactiva Interna

    Energy Technology Data Exchange (ETDEWEB)

    Sedlet, J.; Fairman, W. D.; Robinson, J. J. [Industrial Hygiene and Safety Division, Argonne National Laboratory, Argonne, IL (United States)

    1965-06-15

    , il est possible de l'atteindre. Les emetteurs alpha et les emetteurs beta purs de faible energie presentent la plus grande difficulte du fait que les charges corporelles de ces nucleides doivent ordinairement etre evaluees par une analyse radiochimique du sang ou des excreta. Les auteurs decrivent les separations radiochimiques qui ont ete mises au point et appliquees au Laboratoire national d*Argonne pour doser rapidement ces emetteurs. Le memoire examine d'autre part certains problemes que pose l'obtention de charges corporelles a partir des taux d'excretion, peu apres l'absorption. Pendant ce laps de temps, l'excretion se modifie rapidement et, pour beaucoup de nucleides importants en l'occurrence, a un taux inconnu. Pour les taux d'absorption tres eleves ou tres bas, il n'est pas necessaire de connaitre immediatement la mesure precise des charges corporelles. Cependant, il existe pour chaque radionucleide une dose d'absorption intermediaire pour laquelle il faut pouvoir -determiner sans trop tarder la charge corporelle avec une precision relative, ce qui permet de decider ou non le traitement. Les auteurs examinent les proprietes et les facteurs qui rendent le dosage des elements osteotropes particulierement difficile dans les cas d'accident. (author) [Spanish] Los metodos aplicables en casos de accidente o en situaciones excepcionales tienen que ser suficientemente rapidos y sensibles para proporcionar resultados en plazos que faciliten el tratamiento eficaz de las personas sobreexpuestas. Los plazos disponibles dependeran, en parte, del numero de individuos irradiados. Si se logra obtener en pocas horas resultados utiles, se habra cumplido la funcion primaria de las mediciones rapidas de la carga corporal, que es la de contribuir en toda la medida de lo posible a reducir los danos debidos .a radionuclidos depositados internamente. Los metodos que se citan a continuacion pueden servir para evaluar la contaminacion interna en casos de accidente: recuento gamma y

  16. A Comparison of Radioisotope Methods for River Flow Measurement; Comparaison de methodes radioisotopiques de mesure du debit des cours d'eau; Sravnenie radioizotopnykh metodov izmereniya rechnykh stokov; Comparacion de los metodos radioisotopicos para medir el caudal de los rios

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, C. G.; Smith, D. B. [Wantage Research Laboratory Atomic Energy Research Establishment Wantage, Berks (United Kingdom)

    1963-08-15

    consequent d'aucune utilite comme indicateur dans la mesure du debit d'un cours d'eau s'il n'est pas employe avec un entraineur; mais avec un entraineur, on observe une amelioration marquee de l'exactitude des resultats. {sup 24}Na et {sup 82}Br n'ont accuse aucune adsorption a des distances bien superieures a celles qui sont necessaires pour assurer une brassage lateral; dans la riviere la plus lente, toutefois, on a note, a plus de 660 m du point d'injection, une certaine diminution de {sup 24}Na. Le memoire contient quelques observations sur la dispersion laterale et longitudinale qui, a une certain degre, influe sur l'application generale des methodes radioisotopiques a la mesure du debit des cours d'eau. Les auteurs parviennent a la conclusion que les trois methodes donnent des resultats satisfaisants. Ils preferent, en fin'de compte, la methode d'echantillonnage continue, car elle donne les resultats les plus exacts pour, la quantite minimum d'indicateur. (author) [Spanish] Los autores han empleado los procedimientos de dilucion, muestreo continuo y recuento total en un estudio comparativo de los metodos radioisotopicos de medicion de caudales fluviales en el arroyo Aylburton, en Gloucestershire, y en los rios Usway Burn y Alwin, en Northumberland. Se trata de tres tios de caracteristicas geologicas diferentes, cuyos caudales oscilan entre 2,5 1/s y 3 m{sup 3}/s. En todos los metodos de medicion de caudales que emplean indicadores, la distancia entre el punto en que se efectua la medicion y el punto en que se anade el indicador tiene que ser suficientemente grande para que se produzca una mezcla lateral completa. Por otra parte, no debe ser excesiva para evitar que la dipersion longitudinal supere cierto valor o que se pierda parte del indicador por adsorcion en el lecho fluvial. La dispersion depende de las caracteristicas hidraulicad de la corriente y es inherente al metodo. Por su parte, la adsorcion depende del indicador elegido y de las caracteristicas geologicas

  17. Field transformations to multivalued fields

    Energy Technology Data Exchange (ETDEWEB)

    Kleinert, H [Institut fuer Theoretische Physik, Arnimallee 14, D-14195 Berlin (Germany)

    2007-05-15

    Changes of field variables may lead to multivalued fields which do not satisfy the Schwarz integrability conditions. Their quantum field theory needs special care as is shown in an application to the superfluid and superconducting phase transitions.

  18. Las historias de la narrativa hispanoamericana: Criterios, metodos y ausencias. (Histories of the Latin-American Narrative: Criteria, Methods, and Absences).

    Science.gov (United States)

    Zavalo, Lauro

    This paper explains that materials on the teaching of Latin-American literature are sparse, even though most researchers in the field will dedicate much of their time to teaching. The paper adds that, in scholarly journals, little attention is given to teaching literature, and the topic is also absent from most academic congresses. The paper then…

  19. Risk assessment methods in radiotherapy: Probabilistic safety assessment (PSA); Los metodos de analisis de riesgo en radioterapia: Analisis Probabilistico de seguridad (APS)

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Vera, M. L.; Perez Mulas, A.; Delgado, J. M.; Barrientos Ontero, M.; Somoano, F.; Alvarez Garcia, C.; Rodriguez Marti, M.

    2011-07-01

    The understanding of accidents that have occurred in radiotherapy and the lessons learned from them are very useful to prevent repetition, but there are other risks that have not been detected to date. With a view to identifying and preventing such risks, proactive methods successfully applied in other fields, such as probabilistic safety assessment (PSA), have been developed. (Author)

  20. Vinyl Flanked Difluorobenzothiadiazole-Dithiophene Conjugated Polymer for High Performance Organic Field-Effect Transistors.

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Xianfeng; Sun, Wandong; Chen, Yanlin; Tan, Luxi; Cai, Zheng-Xu; Liu, Zitong; Wang, Lin; Li, Jing; Chen, Wei; Dong, Lichun

    2018-02-21

    Fluorine containing conjugated polymers have been widely applied in high performance organic solar cells, but their use in field-effect transistors is still quite limited. In this work, a conjugated polymer PTFBTV based on difluorobenzothiadiazole (DFBT) and dithiophene was synthesized, utilizing multiple vinylene as linkers. The polymer exhibits a relatively high hole mobility up to 2.0 cm(2) V-1 s(-1) compared with the reported DFBT-oligothiophene based polymers, yet its structural complexity is much simpler. The polymer thin film exhibits a typical 'face on' molecular orientation. A single crystal of its monomer revealed a non-covalent intramolecular contact between fluorine and the neighbouring proton, which strengthens the backbone co-planarity. Meanwhile an intermolecular F...F contact was also observed, which might cause rather scattered lamellar crystallinity for PTFBTV in the solid state.

  1. The effect of cathode bias (field effect) on the surface leakage current of CdZnTe detectors

    International Nuclear Information System (INIS)

    Bolotnikov, A.E.; Hubert Chen, C.M.; Cook, W.R.; Harrison, F.A.; Kuvvetli, I.; Schindler, S.M.; Stahle, C.M.; Parker, B.H.

    2003-01-01

    Surface resistivity is an important parameter of multi-electrode CZT detectors such as coplanar-grid, strip, or pixel detectors. Low surface resistivity results in a high leakage current and affects the charge collection efficiency in the areas near contacts. Thus, it is always desirable to have the surface resistivity of the detector as high as possible. In the past the most significant efforts were concentrated to develop passivation techniques for CZT detectors. However, as we found, the field-effect caused by a bias applied on the cathode can significantly reduce the surface resistivity even though the detector surface was carefully passivated. In this paper we illustrate that the field-effect is a common feature of the CZT multi-electrode detectors, and discuss how to take advantage of this effect to improve the surface resistivity of CZT detectors

  2. Statistical method for the control of the electric power service interruptions (second part); Metodo de control estadistico de las interrupciones del servicio electrico (2a. parte)

    Energy Technology Data Exchange (ETDEWEB)

    Issouribehere, Pedro E.; Barbero, Juan C. [Universidad Nacional de La Plata (UNLP), Buenos Aires (Argentina). Facultad de Ingenieria. Inst. de Investigaciones Tecnologicas para Redes y Equipos Electricos (IITREE-LAT)]. E-mail: iitree@.ing.unlp.edu.ar; Martinez, Jorge L.; Galinski, Alejandro [Ente Nacional Regulador de la Electricidad (ENRE), Buenos Aires (Argentina)

    2001-07-01

    This paper presents the register of interruptions in application points of the concession areas of three concessionaires. The reliability indexes are presented of the controlled sites: interruption ratio {lambda}, time of average reposition r and unavailability Q obtained with the field information recompiled during three years from June 2000. The paper also obtains by concessionaire, the ratios of brief interruptions occurrence which constitutes another indicator of the Electric Service Quality.

  3. Fabrication of coplanar HF analog devices

    International Nuclear Information System (INIS)

    Schulz, G.; Kratz, H.

    1993-01-01

    A thin film technology has to be built up, which allows the reliable and reproducible production of such devices. This technology has to fulfill some general requirements and many specific ones due to the difference of the devices. The general requirements concern the suitability of the technology for industrial production. That means, that the production processes should be reliable, they should allow a high trough-put, and up-scaling should be possible. Processes as passivation or cryo-packaging of the devices belong to this group of requirements as well. The technology for fabrication of the devices splits up into three well distinguishable techniques: deposition of thin films, control of the quality of the deposited layers and patterning of the device structures and contacts. (orig.)

  4. Visual field

    Science.gov (United States)

    ... your visual field. How the Test is Performed Confrontation visual field exam. This is a quick and ... to achieve this important distinction for online health information and services. Learn more about A.D.A. ...

  5. Survey of Pulsed Neutron Source Methods for Multiplying Media; Methodes des Neutrons Pulses Pour l'Etude des Milieux Multiplicateurs; Obzor metodov s ispol'zovaniem istochnikov impul'snykh nejtronov dlya razmnozhayushchej sredy; Estudio Panoramico de los Metodos de Empleo de Fuentes de Neutrons Pulsados en Medios Multiplicadores

    Energy Technology Data Exchange (ETDEWEB)

    Garelis, E. [General Electric Company, Vallecitos Atomic Laboratory, Pleasanton, CA (United States)

    1965-10-15

    -Small-L ). Il discute en outre l'emploi des methodes qui sont fondees sur la reponse a des impulsions pseudoaleatoires et utilisent une correlation entre l'entree et la sortie, pour la determination de la fonction de Green d'un milieu multiplicateur. H montre que les renseignements obtenus par ces methodes sont identiques a ceux fournis par les methodes de la source puisee a repetition, ce qui permet d'appliquer aux premieres les procedes qui ont ete mis au point pour les secondes. (author) [Spanish] En los ultimos afios ha habido dos tendencias principales acerca de la manera mas eficaz de medir la reactividad de parada, empleando fuentes de neutrones pulsados: la primera preconizaba el empleo de metodos tradicionales de medicion con fuentes neutronicas reiteradamente pulsadas, y la segunda propugnaba la aplicacion de metodos basados en una tecnica seudoaleatoria de respuesta a los impulsos, utilizando una correlacion entre los datos de entrada y los de salida. La informacion obtenida con una y otra tecnica es la misma; en teoria, ambos metodos sirven para determinar la funcion de respuesta. Se resefia el desarrollo de las tecnicas de empleo de fuentes de neutrones pulsados aplicadas a sistemas termicos con miras a medir la reactividad, desde los primeros intentos de Sjoestrand hasta el reciente metodo (k{beta}/ Script-Small-L ). Con el metodo usual de empleo de estas fuentes, la propiedad que se procuia determinar es la funcion de Green del conjunto subercritico empleado, es decir, la respuesta del reactor a una fuente de neutrones de funcion delta. El decrecimiento exponencial (e{sup {alpha}t}) de la funcion de Green proporciona una constante de decrecimiento de los neutrones instantaneos que es independiente del espacio. El autor examina los metodos para obtener el valor de la reactividad partiendo de la medida de a, como por ejemplo el metodo de la medicion de la criticidad por neutrones retardados a y el reciente metodo (k{beta}/ Script-Small-L ). Seguidamente examina el

  6. The Marine Magnetotelluric Method (MMT) applied of hydrocarbons exploration in Brazilian waters; Aplicacao do Metodo Magnetotelurico Marinho (MMT) na exploracao de hidrocarbonetos em aguas brasileiras

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Vinicius R.; Flexor, Jean M.; La Terra, Emanuele F.; Fontes, Sergio L. [Observatorio Nacional do Brasil, Rio de Janeiro, RJ (Brazil); Lugao, Patricia P. [Schlumberger, Rio de Janeiro, RJ (Brazil). Western-Geco

    2008-07-01

    Magnetotellurics (MT) is a natural-source, electromagnetic geophysical method of imaging structures below the earth's surface. It is used to map the subsurface Earth's resistivity by measuring the naturally occurring electric and magnetic fields at the Earth's surface. These natural EM fields are generated in the Earth's atmosphere mainly by lightning strokes and by interactions between the solar wind and the ionosphere. Natural variations in the earth's magnetic field induce electric currents (or telluric currents) under the earth's surface. Concurrent measurements of orthogonal components of the electric and magnetic fields allow for the calculation of the impedance tensor, which is complex and frequency-dependent and from which it is possible to gain insight into the resistivity structure of the surrounding material. The marine magnetotelluric method (MMT) is the application of MT method to investigate the sea-floor resistivity's distribution. A MMT sounding with 96 stations was realized in the region of Santos Basin on a subsalt section to assist the interpretation of seismic data in order to estimate the depth of base of the salt (subsalt) since this imaging in general is problematic. The high contrast of the electrical resistivity between the salt and the surrounding sediments is an excellent objective and it constitutes a great opportunity to test the applicability of the MMT method in oil exploration studies. The geological interpretation of the seismic profile of the studied area shows the existence of several bodies of salt with depths of the base that could vary more from 7000 m to more than 9000 m. The top of the body of more important salt of the profile begins to the 3500 m and your base is not solved by the seismic sign that it reaches a maximum depth of 9000 m. The MMT data of the central profile were submitted an inversion procedure - 2D by using the non linear conjugate gradients that produces smooth models for

  7. Torpedo Base - a new method for installation of a conductor casing; Base Torpedo - um novo metodo para instalacao do revestimento condutor

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Emmanuel Franco; Borges, Alexandre Thomaz [PETROBRAS. E and P Engenharia de Producao. Gerencia de Perfuracao e Operacoes Especiais (Brazil)], e-mails: efranco@petrobras.com.br, atborges@petrobras.com.br; Medeiros Junior, Cipriano Jose de [PETROBRAS. Engenharia. Gerencia de Geociencias (Brazil)], e-mail: cipri.intec@petrobras.com.br; Machado, Rogerio Diniz; Souza, Ebenezer Viana de [PETROBRAS. E and P - SERV. Gerencia de Ancoragem (Brazil)], e-mail: rogeriodm@petrobras.com.br, ebnezer_souza@petrobras.com.br

    2008-12-15

    In the last years, PETROBRAS has been optimizing and reducing the cost of the mooring systems through the use of torpedo anchors. It consists of a tubular pile with heavy weight ballast, installed by a process that uses the energy generated by the free fall of the pile from a supply vessel. It is a low cost anchoring concept, with simple fabrication and installation. More than two hundred torpedo anchors were installed offshore Brazil in the last four years. Based on the success of the torpedo anchors for mooring purposes PETROBRAS Exploration and Production department decided to employ the same idea for installing the conductor casing. The benefit was that this installation could be accomplished from an anchor-handling vessel saving important rig time. Another advantage with this installation method is a better foundation provided since no soil is removed during this process. The paper will provide an overview of PETROBRAS Torpedo Base experience in the Albacora Leste field as well as a few other applications of this technology for the production side. After the final installation of two prototypes in the Albacora Leste Field, in Campos Basin, at the end of 2004, the Torpedo Base project was approved by the clients and by PETROBRAS's technological area, having its acquisition requested by five assets (management areas responsible for oil fields located in that basin), in a total of 18 Torpedo Base. The difficulties related to the hiring of services and logistics faced in order to make the installation of the equipment feasible made the E and P technological area to choose to monitor the acquisition and installation of these 18 bases, so as to ensure a smooth transition between the project authors and the technicians in charge of operation of the equipment, ensuring, therefore, the consolidation of the technology. This paper reports PETROBRAS's experience with Torpedo Bases during the installation of these 18 bases in several fields in Campos Basin

  8. Implementation of the Bee Colony Optimization method for the design of fuel cells; Implementacion del metodo Bee Colony Optimization para el diseno de celdas de combustible

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel E, J.; Ortiz S, J. J., E-mail: jaime.esquivel@fi.uaemex.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    The present work shows the results obtained after applying the Bee Colony Optimization algorithm in the design of fuel cells for a BWR. The algorithm that is implemented, works following the behavior that have the bees when pollinating a flowers field. The bees carry out an exhaustive analysis in the cell, so they leave generating diverse configurations where different fuel bars are placed with different uranium enrichments to reach a value mean, with a specific number of gadolinium bars. The behavior of the generated cell is evaluated by means of the use of the commercial code CASMO-4, which shows the variables that allow fixing if the cell fulfills the requirements. Such variables are the local potential peak factor and the neutrons multiplication factor in an infinite medium. (Author)

  9. Calibration methods of plane-parallel ionization chambers used in electron dosimetry; Metodos de calibracao de camaras de ionizacao de placas paralelas para dosimetria de feixes de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Bulla, Roseli Tadeu

    1999-07-01

    The use of linear accelerators in radiotherapy is of great importance in Medicine, and according to international recommendations the electron beam dosimetry has to be performed using plane-parallel ionization chambers, previously calibrated in standard gamma radiation fields at accredited laboratories. In this work, calibration methods of plane-parallel ionization chambers used in dosimetry procedures of high energy electron beams of clinical accelerators were presented, tested and intercompared. The experiments were carried out using gamma radiation beams of {sup 60} Co at the Calibration Laboratory of Clinical Dosemeters at IPEN and electron beams od 4 to 16 MeV at the Radiotherapy Department of Hospital Israelita Albert Einstein, Sao Paulo. A method was chosen to be established at IPEN. Proposals of the calibration procedure, calibration certificate and data sheets are presented. (author)

  10. Method for radon measurement in the subsoil in geothermal prospectus; Metodos de medicion de radon en el subsuelo en prospeccion geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar G, M

    1991-02-15

    The present formless describe the technique for radon measurement in the underground, being able to be used as an additional study in the geothermal prospecting. This methodology has been developed in the National Institute of Nuclear Research of Mexico using a film of cellulose nitrate to detect those emanated alpha particles, by the Rn (222). By means of the trace account in this films its settle down the present radon levels in the underground. The present method thinks about as an alternating one to overcome in it leaves the limitations found in the development of the methodology using a radon emanometer ETR-1, of the trade mark SCINTREX. The radon detected by plastics is also an integral method of measuring in a geothermal field that avoids the problems of variations of radon to pluvial precipitations and barometric variations. These variations affect the results strongly when it is used the punctual sampler as it is the ETR-1. (Author)

  11. Magnetic Field

    DEFF Research Database (Denmark)

    Olsen, Nils

    2015-01-01

    he Earth has a large and complicated magnetic field, the major part of which is produced by a self-sustaining dynamo operating in the fluid outer core. Magnetic field observations provide one of the few tools for remote sensing the Earth’s deep interior, especially regarding the dynamics...... of the fluid flow at the top of the core. However, what is measured at or near the surface of the Earth is the superposition of the core field and fields caused by magnetized rocks in the Earth’s crust, by electric currents flowing in the ionosphere, magnetosphere, and oceans, and by currents induced...... in the Earth by time-varying external fields. These sources have their specific characteristics in terms of spatial and temporal variations, and their proper separation, based on magnetic measurements, is a major challenge. Such a separation is a prerequisite for remote sensing by means of magnetic field...

  12. Phase field

    International Nuclear Information System (INIS)

    Radhakrishnan, B.; Gorti, S.B.; Clarno, K.; Tonks, M.R.

    2015-01-01

    In this work, the phase-field method and its application to microstructure evolution in reactor fuel and clad are discussed. The examples highlight the capability of the phase-field method to capture evolution processes that are influenced by both thermal and elastic stress fields that are caused by microstructural changes in the solid-state. The challenges that need to be overcome before the technique can become predictive and material-specific are discussed. (authors)

  13. S,N-Heteroacene-Based Copolymers for Highly Efficient Organic Field Effect Transistors and Organic Solar Cells: Critical Impact of Aromatic Subunits in the Ladder π-System.

    Science.gov (United States)

    Chung, Chin-Lung; Chen, Hsieh-Chih; Yang, Yun-Siou; Tung, Wei-Yao; Chen, Jian-Wei; Chen, Wen-Chang; Wu, Chun-Guey; Wong, Ken-Tsung

    2018-02-21

    Three novel donor-acceptor alternating polymers containing ladder-type pentacyclic heteroacenes (PBo, PBi, and PT) are synthesized, characterized, and further applied to organic field effect transistors (OFETs) and polymer solar cells. Significant aspects of quinoidal characters, electrochemical properties, optical absorption, frontier orbitals, backbone coplanarity, molecular orientation, charge carrier mobilities, morphology discrepancies, and the corresponding device performances are notably different with various heteroarenes. PT exhibits a stronger quinoidal mesomeric structure, linear and coplanar conformation, smooth surface morphology, and better bimodal crystalline structures, which is beneficial to extend the π-conjugation and promotes charge transport via 3-D transport pathways and in consequence improves overall device performances. Organic photovoltaics based on the PT polymer achieve a power conversion efficiency of 6.04% along with a high short-circuit current density (J SC ) of 14.68 mA cm -2 , and a high hole mobility of 0.1 cm 2 V -1 s -1 is fulfilled in an OFET, which is superior to those of its counterparts, PBi and PBo.

  14. Characterization of the K2-18 multi-planetary system with HARPS. A habitable zone super-Earth and discovery of a second, warm super-Earth on a non-coplanar orbit

    Science.gov (United States)

    Cloutier, R.; Astudillo-Defru, N.; Doyon, R.; Bonfils, X.; Almenara, J.-M.; Benneke, B.; Bouchy, F.; Delfosse, X.; Ehrenreich, D.; Forveille, T.; Lovis, C.; Mayor, M.; Menou, K.; Murgas, F.; Pepe, F.; Rowe, J.; Santos, N. C.; Udry, S.; Wünsche, A.

    2017-12-01

    Aims: The bright M2.5 dwarf K2-18 (Ms = 0.36 M⊙, Rs = 0.41 R⊙) at 34 pc is known to host a transiting super-Earth-sized planet orbiting within the star's habitable zone; K2-18b. Given the superlative nature of this system for studying an exoplanetary atmosphere receiving similar levels of insolation as the Earth, we aim to characterize the planet's mass which is required to interpret atmospheric properties and infer the planet's bulk composition. Methods: We have obtained precision radial velocity measurements with the HARPS spectrograph. We then coupled those measurements with the K2 photometry to jointly model the observed radial velocity variation with planetary signals and a correlated stellar activity model based on Gaussian process regression. Results: We measured the mass of K2-18b to be 8.0 ± 1.9M⊕ with a bulk density of 3.3 ± 1.2 g/cm3 which may correspond to a predominantly rocky planet with a significant gaseous envelope or an ocean planet with a water mass fraction ≳50%. We also find strong evidence for a second, warm super-Earth K2-18c (mp,csinic = 7.5 ± 1.3 M⊕) at approximately nine days with a semi-major axis 2.4 times smaller than the transiting K2-18b. After re-analyzing the available light curves of K2-18 we conclude that K2-18c is not detected in transit and therefore likely has an orbit that is non-coplanar with the orbit of K2-18b although only a small mutual inclination is required for K2-18c to miss a transiting configuration; | Δi| 1-2°. A suite of dynamical integrations are performed to numerically confirm the system's dynamical stability. By varying the simulated orbital eccentricities of the two planets, dynamical stability constraints are used as an additional prior on each planet's eccentricity posterior from which we constrain eb multi-planet systems around M dwarfs. The characterization of the density of K2-18b reveals that the planet likely has a thick gaseous envelope which, along with its proximity to the solar

  15. Control Methods Used in the Department of Metallurgy for Structure and Fuel Elements; Methodes de Controle Utilisees au Departement de Metallurgie pour les Elements de Structure et les Elements Combustibles; Metody kontrolya struktury toplivnykh ehlementov v departamente metallurgii; Metodos de Control Utilizados en el Departamento de Metalurgia para los Elementos Estructurales y Combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Destribats, Marie-Therese; Allain, C.; Prot, A.; Thome, P. [Centre d' Etudes Nucleaires de Saclay (France)

    1965-09-15

    reactores indujeron a utilizar y a perfeccionar numersos metodos no destructivos destinados a inspeccionar los distintos materiales que intervienen en la construccion de esos reactores; en particular radiografia y gamma- grafia, metodos ultrasonicos y empleo de corrientes de Foucault.. A continuacion se enumeran las operaciones de control llevadas a cabo durante la construccion de reactores pertenecientes a las familias EdF (grafito-gas) y EL 4 (agua pesada), y de elementos colaminados; se hace hincapie en ciertos aspectos caracteristicos de estos metodos, algunos de los cuales son ya bien conocidos. Familia EdF: metodos ultrasonicos para medir el espesor de las paredes de tubos de uranio o aleacion de uranio ; localizacion de las cavidades en esos tubos por gammagraffa; empleo de medios ultrasonicos para control de los tratamientos termicos a que se someten los tubos; empleo de procedimientos ultrasonicos para buscar fallas (inclusiones, grietas) en las palanquillas y barras con que se elaboran las vainas de Mg-Zr; control de la estanqueidad de los elementos mediante exudacion de helio. EL4: uso de metodos ultrasonicos y corrientes de Foucault para medir espesores de pared en tubos de Zircaloy, sean de fuerza o de guia; empleo de metodos ultrasonicos para inspeccionar tubos de fuerza de Zircaloy y vainas de acero inoxidable; radiografia al vacio de vainas de Be; control de la estanqueidad de barras huecas mediante exudacion de helio. Elementos colimados: medida del espesor de vainas mediante el empleo de corrientes de Foucault pulsadas; verificacion de la posicion del alma en tubos y placas mediante radiografia, recuento gamma y aplicacion de corrientes de Foucault pulsadas; control de la homogeneidad del combustible por recuento gamma; deteccion de defectos en barras de Zr-U mediante procedimientos ultrasonicos y gammagraficos; determinacion de las zonas despegadas en placas, empleando metodos ultrasonicos, corrientes de Foucault pulsadas y medicion de resistividad. Estos

  16. Synthesis of barium titanate crystalline nanoparticles using hydrothermal microwave method; Obtencao de nanoparticulas cristalinas de titanato de bario usando metodo hidrotermal assistido por microondas

    Energy Technology Data Exchange (ETDEWEB)

    Souza, A.E.; Silva, R.A.; Teixeira, S.R. [Universidade Estadual Paulista (DFQB/FCT/UNESP), Presidente Prudente, SP (Brazil). Dept. de Fisica, Quimica e Biologia. Lab. de Compositos e Ceramicas Funcionais; Moreira, M.L. [Universidade Federal de Sao Carlos (LiEC/UFSCAR), SP (Brazil). Lab. Interdisciplinar de Eletroquimica e Ceramica; Volanti, D.P.; Longo, E. [Universidade Estadual Paulista (LiEC/UNESP), Araraquara, SP (Brazil). Lab. Interdisciplinar de Eletroquimica e Ceramica

    2009-07-01

    The hydrothermal microwave method (HTMW) was used in the synthesis of barium titanate (BaTiO{sub 3}) nanoparticles. The solution was prepared in deionized water by using titanium (IV) isopropoxide (C{sub 12}H{sub 28}O{sub 4}Ti), barium chloride (BaCl{sub 2}.2H{sub 2}O) and potassium hydroxide (KOH). Afterwards it was heated in an adapted conventional microwave oven. The system is composed of a temperature controller with thermocouple, a hermetic camera of reaction made of teflon, a manometer and a safety valve. The solution was heated to 140 deg C, at a 140 deg C/min heating rate, and maintained at this temperature for 40 minutes. The obtained ceramic powder was characterized by using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The XRD data confirms the formation of a high crystalline ceramic material with perovskite structure. The FE-SEM images reveal morphologies with dimensions varying from 27 to 54 nm. (author)

  17. Hydrocarbons thermal maturation: Leopatin method applied to the Parana basin; Maturacao termica de hidrocarbonetos: aplicacao do metodo de Lopatin a Bacia do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Eston, Sergio Medici de; Jardim, Niza S

    1987-12-31

    One of the requirements for the existent of economic deposits of hydrocarbons is that the organic matter has undergone adequate thermal maturation. Several techniques have been proposed in order to quantity the catagenetic state of kerogen, and the Lopatin-Waples methodology permits quantification at any past time and does not require laboratory tests on samples of the material. For this reason it is an useful techniques for predicting mature zones using as basic information the thermal and subsidence histories of each stratum. Lopatin`s technique was applied to the Parana basin, with McKenzie`s crustal stretching model fitted to the data of 18 wells, and the areas predicted as mature for oil and/or gas were in good agreement with the field results. The technique predicted oil phone areas at the east border of the basin for the Ponta Grossa and Irati formation, and also that most of the thermal maturation occurred after the basalt flows of the Cretaceous period. (author) 41 refs., 6 figs., 6 tabs.

  18. Hydrocarbons thermal maturation: Leopatin method applied to the Parana basin; Maturacao termica de hidrocarbonetos: aplicacao do metodo de Lopatin a Bacia do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Eston, Sergio Medici de; Jardim, Niza S.

    1986-12-31

    One of the requirements for the existent of economic deposits of hydrocarbons is that the organic matter has undergone adequate thermal maturation. Several techniques have been proposed in order to quantity the catagenetic state of kerogen, and the Lopatin-Waples methodology permits quantification at any past time and does not require laboratory tests on samples of the material. For this reason it is an useful techniques for predicting mature zones using as basic information the thermal and subsidence histories of each stratum. Lopatin`s technique was applied to the Parana basin, with McKenzie`s crustal stretching model fitted to the data of 18 wells, and the areas predicted as mature for oil and/or gas were in good agreement with the field results. The technique predicted oil phone areas at the east border of the basin for the Ponta Grossa and Irati formation, and also that most of the thermal maturation occurred after the basalt flows of the Cretaceous period. (author) 41 refs., 6 figs., 6 tabs.

  19. Scanning Study of 700 Livers Evaluation of Existing Diagnostic Procedures; Etude Scintigraphique de 700 Foies (Evaluation des Procedures Actuelles de Diagnostic); Issledovanie pecheni 700 bol'nykh s pomoshch'yu skennirovaniya; Exploracion Hepatica de 700 Pacientes (Evaluacion de los Metodos Actuales De Diagnostico); Exploracion Hepatica de 700 Pacientes (Evaluacion de los Metodos Actuales de Diagnostico)

    Energy Technology Data Exchange (ETDEWEB)

    Czerniak, P. [Radium and Isotope Institute, Government Hospital, Tel-Hashomer (Israel)

    1964-10-15

    regeneracion completa. 3. Despues de una derivacion porta-cava, la imagen del higado es mas pequena y la del bazo mas grande, incluso cuando el estado general es satisfactorio. 4. Los agentes citostaticos pueden ser momentaneamente eficaces para ciertas lesiones hepaticas difusas. 5. Ha ocurrido a veces que al explorar de nuevo una lesion dudosa esta ha aparecido como una lesion macroscopica o ha desaparecido totalmente. Por tanto, la epoca en que se efectua la exploracion puede afectar al diagnostico, . Conclusiones: 1. La exploracion hepatica puede considerarse como metodo muy util para el diagnostico clfnico, morfologico y topografico en hepatopatologia. 2. Los resultados pueden mejorarse: a) utilizando aparatos perfeccionados o tecnicas de exploracion estereoscopica, y b) estableciendo una eficaz colaboracion entre el clinico y el cirujano. (author) [Russian] Provodilis' klinicheskie issledovanija, laboratornye analizy, rentgenograficheskoe obsledovanie i skennirovanie pecheni 700 bol'nyh. Za bol'nymi bylo ustanovleno nabljudenie, i v bol'shinstve sluchaev v konechnom itoge diagnoz podtverdilsja. Takim obrazom byla dana ocenka provedennym issledovanijam. Skennirovanie pecheni proizvodilos' s pomoshh'ju bengal'skoj rozy i polivinilpirolidona, mechennyh zolotom-198 i jodom-131 . Pomimo klassicheskogo AR-metoda dlja opredelenija ra- dioizotopnyh kojefficientov pecheni primenjalis' special'nye metody, takie kak treh ili dvuhploskostnoe stereoskennirovanie i kombinirovannoe izotopnoe issledovanie s pomoshh'ju mechennoj zolotom-198 i jodom-131 bengal'skoj rozy. Bol'nye byli razdeleny na vosem' klinicheskih grupp, i sootvetstvenno proizvodilsja sbor i ocenka diagnosticheskih dannyh. Daetsja kratkoe izlozhenie rezul'tatov jetogo issledovanija. V kazhdoj klinicheskoj gruppe analizy provodilis' otdel'no. Naprimer, v 95%iz 65 sluchaev jehinokokkovoj bolezni byl obnaruzhen ogranichennyj uchastok porazhenija. Rentgenovskoe obsledovanie vyjavilo obizvestvlenie tol'ko v 35%jetih sluchaev

  20. Field Report

    DEFF Research Database (Denmark)

    Gorm Hansen, Louise Lyngfeldt

    2012-01-01

    This field report expresses perfectly the kind of confusion almost all of us experience when entering the field. How do we know whether what we’re doing is “right” or not? What in particular should we record when we don’t have time to write down everything among all the myriad impressions thrusting...

  1. Application of Monte Carlo simulation to the standardization of positron emitting radionuclides; Aplicacao do metodo de Monte Carlo na padronizacao de radionuclideos emissores de positrons

    Energy Technology Data Exchange (ETDEWEB)

    Tongu, Margareth Lika Onishi

    2009-07-01

    Since 1967, the Nuclear Metrology Laboratory (LNM) at the Nuclear and Energy Research (IPEN) in Sao Paulo, Brazil, has developed radionuclide standardization methods and measurements of the Gamma-ray emission probabilities per decay by means of 4{pi}{beta}-{gamma} coincidence system, a high accuracy primary method for determining disintegration rate of radionuclides of interest. In 2001 the LNM started a research field on modeling, based on Monte Carlo method, of all the system components, including radiation detectors and radionuclide decay processes. This methodology allows the simulation of the detection process in a 4{pi}{beta}-{gamma} system, determining theoretically the observed activity as a function of the 4{pi}{beta} detector efficiency, enabling the prediction of the behavior of the extrapolation curve and optimizing a detailed planning of the experiment before starting the measurements. One of the objectives of the present work is the improvement of the 4{pi} proportional counter modeling, presenting a detailed description of the source holder and radioactive source material, as well as absorbers placed around the source. The simulation of radiation transport through the detectors has been carried out using code MCNPX. The main focus of the present work is on Monte Carlo modeling of the standardization of positron emitting radionuclides associated (or not) with electron capture and accompanied (or not) by the emission of Gamma radiation. One difficulty in this modeling is to simulate the detection of the annihilation Gamma ray, which arise in the process of positron absorption within the 4{pi} detector. The methodology was applied to radionuclides {sup 18}F and {sup 22}Na. (author)

  2. Impact of field number and beam angle on functional image-guided lung cancer radiotherapy planning

    Science.gov (United States)

    Tahir, Bilal A.; Bragg, Chris M.; Wild, Jim M.; Swinscoe, James A.; Lawless, Sarah E.; Hart, Kerry A.; Hatton, Matthew Q.; Ireland, Rob H.

    2017-09-01

    To investigate the effect of beam angles and field number on functionally-guided intensity modulated radiotherapy (IMRT) normal lung avoidance treatment plans that incorporate hyperpolarised helium-3 magnetic resonance imaging (3He MRI) ventilation data. Eight non-small cell lung cancer patients had pre-treatment 3He MRI that was registered to inspiration breath-hold radiotherapy planning computed tomography. IMRT plans that minimised the volume of total lung receiving  ⩾20 Gy (V20) were compared with plans that minimised 3He MRI defined functional lung receiving  ⩾20 Gy (fV20). Coplanar IMRT plans using 5-field manually optimised beam angles and 9-field equidistant plans were also evaluated. For each pair of plans, the Wilcoxon signed ranks test was used to compare fV20 and the percentage of planning target volume (PTV) receiving 90% of the prescription dose (PTV90). Incorporation of 3He MRI led to median reductions in fV20 of 1.3% (range: 0.2-9.3% p  =  0.04) and 0.2% (range: 0 to 4.1%; p  =  0.012) for 5- and 9-field arrangements, respectively. There was no clinically significant difference in target coverage. Functionally-guided IMRT plans incorporating hyperpolarised 3He MRI information can reduce the dose received by ventilated lung without comprising PTV coverage. The effect was greater for optimised beam angles rather than uniformly spaced fields.

  3. Method and apparatus for balancing the magnetic field detecting loops of a cryogenic gradiometer using trimming coils and superconducting disks

    International Nuclear Information System (INIS)

    Lutes, C.L.

    1982-01-01

    An apparatus for and a method of measuring the difference in intensity between two coplanar magnetic field vector components at two different points in space. The device is comprised of two interconnected, relatively large, loop patterns of opposite, flux cancelling, winding sense. One or both loops include a trimming element that is itself formed of two interconnected, relatively small, loop patterns of opposite, flux cancelling, winding sense. The device is analyzed for imbalance between the two large loops and is then balanced by placing a balancing superconducting disk of the proper characteristic in or near one of the two small loops of the trimming element. The so-trimmed apparatus forms a gradiometer of substantially improved mensuration

  4. Field Notes

    Data.gov (United States)

    US Agency for International Development — This is a mobile application for capturing images , data, and geolocation for USAID projects in the field. The data is then stored on a server in AllNet. The...

  5. External individual monitoring: experiments and simulations using Monte Carlo Method; Monitoracao individual externa: experimentos e simulacoes com o metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Carla da Costa

    2005-07-01

    In this work, we have evaluated the possibility of applying the Monte Carlo simulation technique in photon dosimetry of external individual monitoring. The GEANT4 toolkit was employed to simulate experiments with radiation monitors containing TLD-100 and CaF{sub 2}:NaCl thermoluminescent detectors. As a first step, X ray spectra were generated impinging electrons on a tungsten target. Then, the produced photon beam was filtered in a beryllium window and additional filters to obtain the radiation with desired qualities. This procedure, used to simulate radiation fields produced by a X ray tube, was validated by comparing characteristics such as half value layer, which was also experimentally measured, mean photon energy and the spectral resolution of simulated spectra with that of reference spectra established by international standards. In the construction of thermoluminescent dosimeter, two approaches for improvements have. been introduced. The first one was the inclusion of 6% of air in the composition of the CaF{sub 2}:NaCl detector due to the difference between measured and calculated values of its density. Also, comparison between simulated and experimental results showed that the self-attenuation of emitted light in the readout process of the fluorite dosimeter must be taken into account. Then, in the second approach, the light attenuation coefficient of CaF{sub 2}:NaCl compound estimated by simulation to be 2,20(25) mm{sup -1} was introduced. Conversion coefficients C{sub p} from air kerma to personal dose equivalent were calculated using a slab water phantom with polymethyl-metacrilate (PMMA) walls, for reference narrow and wide X ray spectrum series [ISO 4037-1], and also for the wide spectra implanted and used in routine at Laboratorio de Dosimetria. Simulations of backscattered radiations by PMMA slab water phantom and slab phantom of ICRU tissue-equivalent material produced very similar results. Therefore, the PMMA slab water phantom that can be easily

  6. Inventory Methods in a Conversion Plant; Methodes d'Inventaire dans un Etablissement de Transformation; Metody inventarizatsij na predpriyatii po pererabotke yadernykh materialov; Metodos de Inventario en una Planta de Transformacion

    Energy Technology Data Exchange (ETDEWEB)

    Billy, G. [Commissariat a l' Energie Atomique, Paris (France)

    1966-02-15

    inventarios es la de salvaguardar los intereses de la Comision, evaluar la cuantia de las perdidas y controlar las medidas adoptadas para el almacenaje de los desechos. Para el recuento de las existencias el inspector puede efectuar materialmente el inventario, participar en el o comprobarlo. Este ultimo procedimiento es el que da mejores resultados. Las operaciones de recuento, precedidas de una reunion preparatoria para fijar las modalidades, se efectuan en dos tiempos: la comprobacion del inventario ponderal y la comprobacion de la contabilidad fisica. Las cuestiones que pueden plantearse durante el inventario se refieren a las discrepancias en el peso y el contenido, la eleccion del equipo de pesada, los residuos y la evaluacion de las perdidas. Los metodos de inventario no deben diferir de un pais a otro. Parece preferible subrayar las dificultades que se presentan durante las operaciones y estudiar en comun los medios para evitarlas. (author) [Russian] Osnovnymi zadachami inventarizacii javljajutsja: sobljudenie interesov Komissariata; opredelenie razmerov poter'; kontrol' mer, prinimaemyh dlja hranenija othodov. Inspektirujushhee lico mozhet provodit' fakticheskuju inventarizaciju, uchastvovat' v nej ili proverjat' ee. Jetot poslednij metod daet nailuchshie rezul'taty. Operacii po uchetu, kotorym predshestvuet podgotovitel'noe soveshhanie dlja opredelenija sposobov ucheta, provodjatsjav dva jetapa: snachala proverjaetsja nalichie po vesu, azatemdoku mentacija. Voprosy, voznikajushhie v svjazi s inventarizaciej i kasajushhiesja vesa, soderzhanija poko- vok, vybora vesov dlja vzveshivanija, normy othodov i ocenki poter', razreshajutsja otpravite- lem i poluchatelem. Metody inventarizacii v odnom gosudarstve ne dolzhny sil'no otlichat'sja ot takovyh v drugom gosudarstve. Neobhodimo podcherknut' trudnosti, voznikajushhie v processe inven- tarizacii, i zhelatel'nost' otyskanija sovmestnyh putej ih preodolenija. (author)

  7. Selfdecomposable Fields

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.; Sauri, Orimar; Szozda, Benedykt

    In the present paper we study selfdecomposability of random fields, as defined directly rather than in terms of finite-dimensional distributions. The main tools in our analysis are the master Lévy measure and the associated Lévy-Itô representation. We give the dilation criterion for selfdecomposa......In the present paper we study selfdecomposability of random fields, as defined directly rather than in terms of finite-dimensional distributions. The main tools in our analysis are the master Lévy measure and the associated Lévy-Itô representation. We give the dilation criterion...... for selfdecomposability analogous to the classical one. Next, we give necessary and sufficient conditions (in terms of the kernel functions) for a Volterra field driven by a Lévy basis to be selfdecomposable. In this context we also study the so-called Urbanik classes of random fields. We follow this with the study...... of existence and selfdecomposability of integrated Volterra fields. Finally, we introduce infinitely divisible field-valued Lévy processes, give the Lévy-Itô representation associated with them and study stochastic integration with respect to such processes. We provide examples in the form of Lévy...

  8. Selfdecomposable Fields

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole E.; Sauri, Orimar; Szozda, Benedykt

    In the present paper we study selfdecomposability of random fields, as defined directly rather than in terms of finite-dimensional distributions. The main tools in our analysis are the master L\\'evy measure and the associated L\\'evy-It\\^o representation. We give the dilation criterion for selfdec......In the present paper we study selfdecomposability of random fields, as defined directly rather than in terms of finite-dimensional distributions. The main tools in our analysis are the master L\\'evy measure and the associated L\\'evy-It\\^o representation. We give the dilation criterion...... for selfdecomposability analogous to the classical one. Next, we give necessary and sufficient conditions (in terms of the kernel functions) for a Volterra field driven by a L\\'evy basis to be selfdecomposable. In this context we also study the so-called Urbanik classes of random fields. We follow this with the study...... of existence and selfdecomposability of integrated Volterra fields. Finally, we introduce infinitely divisible field-valued L\\'evy processes, give the L\\'evy-It\\^o representation associated with them and study stochastic integration with respect to such processes. We provide examples in the form of L...

  9. Random Fields

    Science.gov (United States)

    Vanmarcke, Erik

    1983-03-01

    Random variation over space and time is one of the few attributes that might safely be predicted as characterizing almost any given complex system. Random fields or "distributed disorder systems" confront astronomers, physicists, geologists, meteorologists, biologists, and other natural scientists. They appear in the artifacts developed by electrical, mechanical, civil, and other engineers. They even underlie the processes of social and economic change. The purpose of this book is to bring together existing and new methodologies of random field theory and indicate how they can be applied to these diverse areas where a "deterministic treatment is inefficient and conventional statistics insufficient." Many new results and methods are included. After outlining the extent and characteristics of the random field approach, the book reviews the classical theory of multidimensional random processes and introduces basic probability concepts and methods in the random field context. It next gives a concise amount of the second-order analysis of homogeneous random fields, in both the space-time domain and the wave number-frequency domain. This is followed by a chapter on spectral moments and related measures of disorder and on level excursions and extremes of Gaussian and related random fields. After developing a new framework of analysis based on local averages of one-, two-, and n-dimensional processes, the book concludes with a chapter discussing ramifications in the important areas of estimation, prediction, and control. The mathematical prerequisite has been held to basic college-level calculus.

  10. A Monte Carlo simulation for the field theory with quartic interaction

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Sergio Mittmann dos [Instituto Federal de Educacao, Ciencia e Tecnologia do Rio Grande do Sul (IFRS), Porto Alegre, RS (Brazil)

    2011-07-01

    Full text: In the work [1-S. M. Santos, B. E. J. Bodmann and A. T. Gomez, Um novo metodo computacional para a teoria de campos na rede: resultados preliminares, IV Escola do Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, 2002; and 2-S. M. Santos and B. E. J. Bodmann, Simulacao na rede de teorias de campos quanticos, XXVIII Congresso Nacional de Matematica Aplicada e Computacional (CNMAC), Sao Paulo, 2005], a computational method on the lattice was elaborated for the problem known as scalar field theory with quartic interaction (for instance, see: J. R. Klauder, Beyound conventional quantization, Cambridge: Cambridge University Press, 2000). This one introduced an algorithm, which allows the simulation of a given field theory and is independent of the lattice spacing, by redefining the fields and the parameters (the mass m and the coupling constant g). This kind of approach permits varying the dimension of the lattice without changing the computational complexity of the algorithm. A simulation was made using the Monte Carlo method, where the renormalized mass m{sub R}, the renormalized coupling constant g{sub R} and the two point correlation function were determined with success. In the present work, the genuine computational method is used for new simulations. Now, the Monte Carlo method is not used just for the simulation of the algorithm, like in [1, 2], but also for defining the adjust parameters (the mass and the coupling constant), introduced ad hoc in [1, 2]. This work presents the first simulations' outcomes, where best results that [1, 2] were determined, for the renormalized mass and the renormalized coupling constant. (author)

  11. Kinetic equilibrium for an asymmetric tangential layer with rotation of the magnetic field

    Science.gov (United States)

    Belmont, Gérard; Dorville, Nicolas; Aunai, Nicolas; Rezeau, Laurence

    2015-04-01

    Finding kinetic equilibria for tangential current layers is a key issue for modeling plasma phenomena such as magnetic reconnection instabilities, for which theoretical and numerical studies have to start from steady-state current layers. Until 2012, all theoretical models -starting with the most famous "Harris" one- relied on distribution functions built as mono-valued functions of the trajectories invariants. For a coplanar anti-symmetric magnetic field and in absence of electric field, these models were only able to model symmetric variations of the plasma, so precluding any modeling of "magnetopause-like'' layers, which separate two plasmas of different densities and temperatures. Recently, the "BAS" model was presented (Belmont et al., 2012), where multi-valued functions were taken into account. This new tool is made necessary each time the magnetic field reversal occurs on scales larger than the particle Larmor radii, and therefore guaranties a logical transition with the MHD modeling of large scales. The BAS model so provides a new asymmetric equilibrium. It has been validated in a hybrid simulation by Aunai et al (2013), and more recently in a fully kinetic simulation as well. For this original equilibrium to be computed, the magnetic field had to stay coplanar inside the layer. We present here an important generalization, where the magnetic field rotates inside the layer (although restricted to a 180° rotation hitherto). The tangential layers so obtained are thus closer to those encountered at the real magnetopause. This will be necessary, in the future, for comparing directly the theoretical profiles with the experimental ones for the various physical parameters. As it was done previously, the equilibrium is presently tested with a hybrid simulation. Belmont, G.; Aunai, N.; Smets, R., Kinetic equilibrium for an asymmetric tangential layer, Physics of Plasmas, Volume 19, Issue 2, pp. 022108-022118-10, 2012 Aunai, N.; Belmont, G.; Smets, R., First

  12. Field theories with subcanonical fields

    International Nuclear Information System (INIS)

    Bigi, I.I.Y.

    1976-01-01

    The properties of quantum field theories with spinor fields of dimension less than the canonical value of 3/2 are studied. As a starting point for the application of common perturbation theory we look for the linear version of these theories. A gange-interaction is introduced and with the aid of power counting the renormalizability of the theory is shown. It follows that in the case of a spinor-field with negative dimension renormalization can only be attained if the interaction has a further symmetry. By this symmetry the theory is determined in an unequivocal way. The gange-interaction introduced in the theory leads to a spontaneous breakdown of scale invariance whereby masses are produced. At the same time the spinor-field operators can now be separated in two orthogonal sections with opposite norm. It is proposed to use the section with negative (positive) norm to describe hadrons (leptons) respectively. (orig./WL) [de

  13. Design and construction of a broad-band electric field probe

    International Nuclear Information System (INIS)

    Bahrami, A.; Sohrabi, M.; Farvadin, D.

    1996-01-01

    The design of a broad-band electric field probe based on a resistive film diode antenna on RT/Duroid substrate to measure the electric RF/MW fields as constructed at the National Radiation Protection Department (NRPD) of the Atomic Energy Organization of Iran (AEOI) are described in this paper. A square law diode detector with a matching circuit and also low pass filter have been used to produce a dc current proportional to the square RF voltage across the resistive antenna gap. A double-strip coplanar waveguide has also been designed to transfer this dc current to an amplifier with an output signal showing the electric field intensity in one direction. By using three mutually orthogonal resistive antennas, an isotropic electric field probe was made. All parts of this probe have been completely modeled and solved by the MATLAB computer program to determine the optimum values of the elements of the probe. The frequency response of the probe has also been theoretically found to be flat in the range 0.8 to 3 GHz. It was found to be quite satisfactory compared with those of similar probes commercially available. The probe is being used routinely in practice. (author)

  14. Gauge fields

    International Nuclear Information System (INIS)

    Itzykson, C.

    1978-01-01

    In these notes the author provides some background on the theory of gauge fields, a subject of increasing popularity among particle physicists (and others). Detailed motivations and applications which are covered in the other lectures of this school are not presented. In particular the application to weak interactions is omitted by referring to the introduction given by J. Ilipoulos a year ago (CERN Report 76-11). The aim is rather to stress those aspects which suggest that gauge fields may play some role in a future theory of strong interactions. (Auth.)

  15. Comparative Study of the Methods Used for the Computer Resolution of Composite Gamma-Ray Spectra; Etude Comparative des Methodes Utilisees pour la Resolution de Spectres Gamma Complexes au Moyen d'un Ordinateur; Sravnitel'noe izuchenie metodov razresheniya sostavnykh gamma-spektrov pri pomoshchi schetno-reshayushchego ustrojstva; Estudio Comparativo de los Metodos Aplicados para Resolver Espectros Gamma Complejos Mediante Calculadoras

    Energy Technology Data Exchange (ETDEWEB)

    DeHaan, A. Jr.; Leventhal, L.; Benson, P. [Tracerlab, Richmond, CA (United States)

    1965-10-15

    'a resolution; 2. Resolution du pic sans elimination; 3. Etablissement d'un ensemble d'equ'ations lineaires simultanees du meme ordre que le nombre de radionucleides presents dans le melange et solution de ces equations; 4. Evaluation des concentrations non connues par la methode des moindres carres, classique ou ponderee; 5. Combinaison des methodes statistiques et des methodes des moindres carres utilisant la regression lineaire multiple progressive, en s'efforcant d'integrer des processus decisifs dans l'analyse. Pour chaque methode d'analyse appliquee a des melanges de radionucleides, les auteurs fournissent une estimation statistique des erreurs de mesure de la concentration des radionucleides. (author) [Spanish] La resolucion de mezclas complejas de emisores gamma se ha simplificado gracias al empleo de espectrometros gamma muy perfeccionados en asociacion con calculadoras numericas. En la actualidad, los laboratorios pueden en general disponer de estos instrumentos o tener facilmente acceso a ellos. En la memoria se examinan los metodos seguidos en el laboratorio de los autores para determinar la concentracion de cada radionuclido emisor gamma contenido en muestras de precipitaciones radiactivas, y se comparan los resultados obtenidos por los diferentes metodos matematicos aplicables a las muestras compuestas. Los datos proporcionados por las calculadoras se comparan con los resultados obtenidos por analisis radioquimico de la muestra. Se han analizado muestras binarias por los metodos mencionados, operacion que se extendio despues a las mezclas integradas por muchos componentes. Se ha elaborado un metodo de computo que normaliza los espectros gamma para reducir al mfnimo el efecto de la deriva del espectrometro a largo plazo, y representa el espectro segun un sistema de coordenadas, una de las cuales es la energia. Se han investigado los efectos de un 'fotopico imprevisto', de una componente de intensidad cero y de picos superpuestos en la resolucion segun los

  16. Uses and updating of the Benders method in the integer-mixed programming in the planning of the electric power systems expansion; Usos y actualizacion del metodo de Benders en la programacion entera-mixta y en la planeacion de la expansion de los sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    De la Torre Vega, Eli

    1997-04-01

    of some potential improvements that the proposed method has. [Espanol] En el primer capitulo se presenta la deduccion de los cortes de Benders partiendo de las propiedades de la dualidad. Tambien se presentan las propiedades de los cortes de Benders asi como el algoritmo inicial de Benders para resolver cualquier problema de programacion lineal entera-mixta. En el segundo capitulo, se presenta el problema de la planeacion de la expansion de los medios de generacion y transmision en un sistema electrico de potencia, las distintas estructuras de la programacion matematica a que da lugar y como se puede adaptar el metodo de Benders a estas. En el tercer capitulo se presentan las aportaciones teoricas de este trabajo: a) Como inicializar el problema maestro para aprovechar la experiencia adquirida despues de haber resuelto un problema similar, de modo que se pueda resolver mas eficientemente, la sucesion de problemas de programacion lineal entero-mixtos que surgen al resolver el problema de la planeacion de la expansion de los medios de generacion y transmision en un sistema electrico de potencia. b) Como generar un problema maestro cuya solucion optima continua corresponda al optimo continuo del problema entero-mixto, de modo que la busqueda de soluciones enteras se realice en la vecindad del optimo continuo. c) Como generar una solucion entera, cercana al optimo continuo del problema entero-mixto, que tenga mucha probabilidad de ser factible, y que quizas sea la solucion optima entera, en un tiempo menor al que se requiere para resolverlo en forma exacta. Ademas, se presentan otras ideas que se le pueden incorporar al metodo de Benders. A fin de mostrar la efectividad de las ideas propuestas, en el capitulo 4 se presentan los resultados obtenidos al resolver varios problemas usando: 1. El metodo de Benders in actualizacion, 2. El metodo de Ramificacion y Acotamiento, 3. La actualizacion de Benders al agregar restricciones y 4. La actualizacion de Benders al considerar

  17. Initial thermal state of the Los Humeros, Puebla, Mexico, geothermal field; Estado termico inicial del campo geotermico de Los Humeros, Puebla, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Gutierrez, Alfonso [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: aggarcia@iie.org.mx

    2009-01-15

    The initial temperatures field is presented for 40 wells in the Los Humeros geothermal reservoir, along with an elevation curve based on the formation temperature or the most probable reservoir temperature. Stabilized temperatures were estimated using the Radial Spherical Heat Flow method, chosen over the Horner method based on the numerical simulation of the circulation and stop processes of well H-26. In this well, the last temperature log series was reproduced, considering circulation losses. The temperatures were used to produce isothermal curves over three geological sections of the field, which represent the initial distribution of temperatures in the reservoir and show the thermal characteristics and the relationships among thermal anomalies and faults in the reservoir. The elevation curve plotted against the initial temperature of the formation was generated based on detection of the main feed zones at each well, which in turn was developed using detailed analyses of diverse information, such as temperature logs, circulation losses, lithology, well completion, and heat velocities. Based on the results, two groups of wells may be distinguished: one between 1000 and 1600 masl with temperatures from 290 to 330 degrees Celsius, and one between 900 and 0 masl with temperatures from 300 to 400 degrees Celsius. [Spanish] En este trabajo se presenta el campo de temperatura inicial del yacimiento geotermico de Los Humeros y una curva de elevacion contra la temperatura de formacion o temperatura mas probable del yacimiento, obtenida para 40 pozos del campo. Las temperaturas estabilizadas se estimaron mediante el metodo de Flujo de Calor Esferico Radial, y su eleccion sobre las temperaturas del metodo de Horner se soporta con simulacion numerica de los procesos de circulacion y paro del pozo H-26, en la cual la ultima serie de registros se reprodujo considerando perdidas de circulacion. Con estas temperaturas se generaron curvas isotermicas para tres secciones

  18. Il metodo mitico e i cattivi pensieri

    Directory of Open Access Journals (Sweden)

    Elio Franzini

    2012-05-01

    Full Text Available Moving from a definition of his « mythical method», the essay aims to outline the so-called «Philosophy of Art» of Paul Valéry. It sketches a portrait of the French author as an authentic philosopher of phenomenology able to define in a non-abstract way what must be intended with «aesthetics».

  19. Le narrazioni come metodo di indagine sociologica

    Directory of Open Access Journals (Sweden)

    Rita Bichi

    2012-04-01

    Full Text Available L'incontro trentino ha dimostrato l'interesse crescente dei giovani sociologi per lo sviluppo dei metodi narrativi e la capacità che questi hanno di essere efficaci nell'analisi di svariati temi, dai racconti di malattia alle narrazioni identitarie, dallo studio di lavoro e organizzazioni a quello delle migrazioni, di genere e memoria. Tuttavia, l'interesse della sociologia italiana va visto in un quadro di sviluppo più ampio a livello europeo e americano dove, a partire dagli anni '90, l'intervento di alcuni autori come Lyotard, Bruner e Macintyre, ha sancito quella che alcuni autori hanno definito svolta narrativa. La sociologia, infatti, tende sempre più a valorizzare la narrazione come processo di conoscenza peculiare che è attivato costantemente nella vita quotidiana; la "rivoluzione" risiede nel fatto che la narrazione diventa oggetto della sociologia e la disciplina stessa valorizza il suo uso sia come strumento di indagine scientifica, sia come modo di conoscere che come modo di comunicare, rivendicando la legittimità scientifica all'ascolto della parola diretta degli individui coinvolti all'interno delle ricerche di stampo sociologico.

  20. Il metodo storico nella critica testuale

    OpenAIRE

    Giangrande, Giusseppe

    2008-01-01

    Se ofrecen ejemplos de cómo es posible explicar por medio de un enfoque histórico pasajes controvertidos de autores griegos y latinos. Passages of Greek and Latin authors which many a critic cannot understand can often be explained by placing them in the proper historical perspective.

  1. Recent Radiochemical Procedures for Bio-Assay Studies at Trombay; Methodes Radiochimiques d'Analyse Biologique Employees a Trombay; Nedavno razrabotannye v trombee radiokhimicheskie metody dlya biologicheskikh issledovanij; Regientes Metodos Radioquimicos Aplicados al Analisis Biologico en Trombay

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, P. R.; Bhat, I. S.; Rudran, Kamala; Iyengar, M. A.R.; Koshy, Elizabeth; Waingankar, Urmila S.; Khanolkar, Vasanti S. [Health Physics Division, Atomic Energy Establishment Trombay, Bombay (India)

    1964-10-15

    travaux accomplis au laboratoire d'analyses biologiques depuis 1958. (author) [Spanish] El laboratorio de analisis biologicos de Trombay efectua anualmente cerca de dos mil analisis de orina para determinar diferentes radionuclidos, siendo los isotopos de mayor interes el {sup 232}Th, {sup 228}Th, {sup 226}Ra, {sup 224}Ra, {sup 228}Ra, U natural, productos de fision y {sup 239}Pu, asip como el {sup 60}Co, {sup 32}P, {sup 131}I, {sup 32}P, {sup 137}Cs, {sup 3}H, {sup 90}Sr, etc. El analisis rapido de un gran numero de muestras de baja actividad exige el perfeccionamiento de tecnicas especiales, sobre todo cuando se desea un alto grado de especificidad, unido a un elevado rendimiento. La' orina presenta una matriz muy complicada, con una elevada proporcion de sustancias organicas complejantes y contenido variable de sales. Los procedimientos de calcinacion por via humeda exigen un tiempo considerable y resultan engorrosos cuando se han de destruir muestras de aproximadamente 1 a 1,5 l. El trabajo deseribe algunos metodos recientemente desarrollados en el laboratorio de los autores y proporciona detalles de estudios sobre indicadores que han intervenido en el desarrollo de aquellos metodos. Radio-228: Se mide el mesotorio contenido en la orina despues de separar el {sup 228}Ac en equilibrio radiactivo. El radio presente en la orina se coprecipita con BaSO{sub 4}, teniendose en cuenta que sigue formandose {sup 228}Ac. El precipitado se disuelve en acido perclorico despues de anadir como portadores Pb, Bi y La. Los sulfatos insolubles se precipitan con H{sub 2}SO{sub 4} diluido y el {sup 228}Ac que permanece en solucion, despues de ser arrastrado con F{sub 3}La, se somete a recuento de actividad beta y se comprueba la disminucion de actividad. La cantidad de {sup 228}Ra se calcula a partir de la actividad observada en el {sup 228}Ac despues de introducir la oportuna correccion para tener en cuenta la desintegracion y el rendimiento de la recuperacion quimica. Torio: El trabajo

  2. Field theory

    CERN Multimedia

    1999-11-08

    In these lectures I will build up the concept of field theory using the language of Feynman diagrams. As a starting point, field theory in zero spacetime dimensions is used as a vehicle to develop all the necessary techniques: path integral, Feynman diagrams, Schwinger-Dyson equations, asymptotic series, effective action, renormalization etc. The theory is then extended to more dimensions, with emphasis on the combinatorial aspects of the diagrams rather than their particular mathematical structure. The concept of unitarity is used to, finally, arrive at the various Feynman rules in an actual, four-dimensional theory. The concept of gauge-invariance is developed, and the structure of a non-abelian gauge theory is discussed, again on the level of Feynman diagrams and Feynman rules.

  3. Electronic methods for discriminating scintillation shapes; Methodes electroniques de discrimination des formes des impulsions issues de scintillateurs; Ehlektronnye metody diskriminatsii form stsintillyatsii; Metodos electronicos de discriminacion de forma de impulsos de centelleo

    Energy Technology Data Exchange (ETDEWEB)

    Forte, M; Konsta, A; Maranzana, C [European Atomic Energy Community, CCR, ISPRA (Italy)

    1962-04-15

    ne doit se faire qu'entre deux types d'impulsions seulement (neutrons et rayons gamma, par exemple), on a egalement envisage l'emploi de reseaux passifs qu'il serait possible d'ameliorer et de simplifier. Les auteurs ont fait l'essai de quelques reseaux; ils sont notamment parvenus, en presence d'un bruit de fond du a des rayons gamma, a realiser la discrimination dans des scintillateurs liquides de protons de recul ne delivrant que de faibles impulsions (quelques dizaines de photo-electrons) et celle de fragments de capture de neutrons dans des scintillateurs liquides contenant du bore. Certains de ces reseaux ont pu fonctionner avec des impulsions de meme polarite issues de deux des dernieres dynodes, et meme avec les impulsions de sortie delivrees par une seule electrode. Il y a la une possibilite interessante pour les cas ou il est indique d'utiliser l'anode separement, par exemple pour le cycle de synchronisation. (author) [Spanish] Como ya se ha senalado, la forma de los impulsos emitidos por un centelleador, que es caracteristica del tipo de particula excitante (electron, proton, particulas alfa, etc.), puede convertirse en una amplitud de impulso como parametro independiente. Ello permite determinar, utilizando un analizador multicanal, la composicion de un haz mixto de particulas que excite el centelleador. Este metodo se ha aplicado con exito empleando varios centelleadores de tipo organico e inorganico. Los autores describen con detalle las tecnicas electronicas utilizadas para convertir la forme de los impulsos. En el caso mas sencillo de discriminacion entre solo dos clases de impulsos (por ejemplo, discriminacion de neutrones y rayos gamma), se ha estudiado la conveniencia de utilizar redes pasivas, susceptibles de nuevos perfeccionamientos y simplificaciones. Se han ensayado varios tipos de redes y el principal resultado obtenido consiste en la discriminacion, en presencia de un fondo gamma, de los protones de retrocesco en centelleadores liquidos

  4. Gauge fields

    International Nuclear Information System (INIS)

    Mills, R.

    1989-01-01

    This article is a survey of the history and ideas of gauge theory. Described here are the gradual emergence of symmetry as a driving force in the shaping of physical theory; the elevation of Noether's theorem, relating symmetries to conservation laws, to a fundamental principle of nature; and the force of the idea (''the gauge principle'') that the symmetries of nature, like the interactions themselves, should be local in character. The fundamental role of gauge fields in mediating the interactions of physics springs from Noether's theorem and the gauge principle in a remarkably clean and elegant way, leaving, however, some tantalizing loose ends that might prove to be the clue to a future deeper level of understanding. The example of the electromagnetic field as the prototype gauge theory is discussed in some detail and serves as the basis for examining the similarities and differences that emerge in generalizing to non-Abelian gauge theories. The article concludes with a brief examination of the dream of total unification: all the forces of nature in a single unified gauge theory, with the differences among the forces due to the specific way in which the fundamental symmetries are broken in the local environment

  5. Autoblocking dose-limiting normal structures within a radiation treatment field: 3-D computer optimization of 'unconventional' field arrangements

    International Nuclear Information System (INIS)

    Bates, Brian A.; Cullip, Timothy J.; Rosenman, Julian G.

    1995-01-01

    Purpose/Objective: To demonstrate that one can obtain a homogeneous dose distribution within a specified gross tumor volume (GTV) while severely limiting the dose to a structure surrounded by that tumor volume. We present three clinical examples below. Materials and Methods: Using planning CT scans from previously treated patients, we designed variety of radiation treatment plans in which the dose-critical normal structure was blocked, even if it meant blocking some of the tumor. To deal with the resulting dose inhomogeneities within the tumor, we introduced 3D compensation. Examples presented here include (1) blocking the spinal cord segment while treating an entire vertebral body, (2) blocking both kidneys while treating the entire peritoneal cavity, and (3) blocking one parotid gland while treating the oropharynx in its entirety along with regional nodes. A series of multiple planar and non-coplanar beam templates with automatic anatomic blocking and field shaping were designed for each scenario. Three-dimensional compensators were designed that gave the most homogeneous dose-distribution for the GTV. For each beam, rays were cast from the beam source through a 2D compensator grid and out through the tumor. The average tumor dose along each ray was then used to adjust the compensator thickness over successive iterations to achieve a uniform average dose. DVH calculations for the GTV, normal structures, and the 'auto-blocked' structure were made and used for inter-plan comparisons. Results: These optimized treatment plans successfully decreased dose to the dose-limiting structure while at the same time preserving or even improving the dose distribution to the tumor volume as compared to traditional treatment plans. Conclusion: The use of 3D compensation allows one to obtain dose distributions that are, theoretically, at least, far superior to those in common clinical use. Sensible beam templates, auto-blocking, auto-field shaping, and 3D compensators form a

  6. Proposed method for the hydraulic design of ski-jump energy dissipators in dam spillways considering the occurrence of scour holes downstream of the structure; Metodo propuesto para el diseno hidraulico de trampolines empleados como disipadores de energia en aliviaderos para presas, considerando la ocurrencia del cono de socavacion al pie del mismo

    Energy Technology Data Exchange (ETDEWEB)

    Pardo-Gomez, Rafael [Centro de Investigaciones Hidraulicas (Cuba)

    2008-04-15

    Ski-jump energy dissipators are widely used in hydraulic engineering because of their well-known effectiveness. Nevertheless, some uncertainty exits associated with the dimensions of the scour hole appearing downstream of the structure. This paper presents a new method for solving this problem. This method includes spillway stability checking as part of the design process and also stability checking of any other construction near the energy dissipation zone. [Spanish] Los disipadores de energia tipo trampolin tienen amplia utilizacion en la practica de la ingenieria hidraulica por su probada eficacia; sin embargo, su diseno esta sujeto a cierto grado de incertidumbre en cuanto a la prediccion de las dimensiones del cono de socavacion que habra de producirse aguas abajo de la estructura. En el presente trabajo se muestra un metodo novedoso, mediante el cual el autor soluciona el aspecto antes referido, toda vez que se incluye como parte del proceso de diseno la comprobacion de la estabilidad del propio aliviadero o de cualquier otra obra cercana a la zona de disipacion de energia.

  7. Double-Sampling Method for Carrying Out Quality Control of a Fabrication Process; Methode du Double Echantillonnage pour le Controle de la Qualite d'un Procede de Fabrication; Metod dvukh obraztsov dlya osushchestvleniya kontrolya za kachestvom v protsesse izgotovleniya; Metodo de Muestreo Doble para el Control de Calidad de un Proceso de Fabricacion

    Energy Technology Data Exchange (ETDEWEB)

    Cerrolaza, J. A.; Lago, A.; Montojo, Rosa M. [Junta de Energia Nuclear, Madrid (Spain)

    1966-02-15

    taille des echantillons et le degre de controle sont determines en fonction des risques inherents a la premiere et a la deuxieme condition. Bien que cette methode soit applicable, elle est fort peu pratique quand il s'agit de controler des pieces de reacteurs, car les echantillons qu'elle exige sont de dimensions excessives. Le memoire expose une methode analogue a celle de Cave mais qui consiste a etablir un double echantillonnage dans lequel la taille moyenne de l'echantillon est beaucoup plus reduite. (author) [Spanish] La fabricacion de componentes que han de ser empleados en reactores nucleares presenta dos caracteristicas fundamentales que condicionan el proceso: la exigencia de una calidad muy elevada que limita a valores muy bajos el porcentaje de piezas defectuosas admisibles, y el coste muy alto de cada uno de los componentes. Estas dos condiciones obligan a que el control durante la fabricacion posea una curva de operacion con potencia muy elevada, y, por otra parte, a que el numero de piezas destruidas en cada inspeccion sea un pequeno como se pueda, siempre que se cumpla la condicion anterior. Los metodos usuales de control, basados en fijar el riesgo de primera especie, no son aplicables, ya que en general su eficacia no es suficiente. Cave ha desarrollado un metodo en que, tanto el tamano de las muestras como los limites de control, se fijan en funcion de los riesgos de primera y segunda especie. Este metodo, si bien es aplicable, resulta poco practico en el control de componentes para reactores, ya que se necesitan muestras de un tamano excesivamente grande. En el presente trabajo se desarrolla un metodo semejante al de Cave, pero en el que se establece un muestreo doble, con lo que el tamano medio de la muestra es mucho mas reducido. (author) [Russian] Pri izgotovlenii komponentov dlja ispol'zovanija v reaktorah reshajushhee znachenie imejut dva osnovnyh faktora, a imenno: neobhodimost' obespechit' ochen' vysokoe kachestvo, dopuskajushhee lish' ochen

  8. Lacunarity of geophysical well logs in the Cantarell oil field, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Arizabalo, Ruben Dario [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Oleschko, Klavdia [Centro de Geociencias, Universidad Nacional Autonoma de Mexico, Juriquilla, Queretaro (Mexico); Korvin, Gabor [King Fahd University, Dhahran (Saudi Arabia); Lozada, Manuel [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Castrejon, Ricardo [Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico); Ronquillo, Gerardo [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico)

    2006-04-15

    Lacunarity and fractal variations in geophysical well logs are associated with stratigraphic and petrophysical properties of the naturally fractured Cantarell field in the Gulf of Mexico. Neutron porosity (NPHI), density (RHOB, DRHO, PEF), resistivity (LLD, LLS, MSFL), natural radioactivity (GR, CGR, URAN, POTA, THOR) and caliper (CALI) logs are studied. The resistivity logs yielded remarkably high lacunarity values, especially in the hydrocarbon source- and reservoir rocks. Lacunarity {delta} was found to depend on the resolution and radial depth of penetration of the logging method. It systematically increased in the following order: {delta}(RHOB) < {delta}(CALI) < {delta}(PEF) < {delta}(URAN) < {delta}(GR) < {delta}(NPHI) < {delta}(POTA) < {delta}(CGR) < {delta}(THOR) < {delta}(MSFL) < {delta}(DRHO) < {delta}(LLS) < {delta}(LLD). [Spanish] En este trabajo fueron analizadas las variaciones fractales y de lagunaridad de los registros geofisicos de pozo, con el fin de asociarlos con las propiedades estratigraficas y petrofisicas del yacimiento naturalmente fracturado de Cantarell, en el Golfo de Mexico. Los registros considerados fueron: porosidad neutron (NPHI), densidad (RHOB, DRHO, PEF), resistividad (LLD, LLS, MSFL), radiactividad natural (GR, CGR, URAN, POTA, THOR) y caliper (CALI). Los registros de resistividad produjeron valores de lagunaridad notablemente altos, especialmente en las rocas generadoras y almacenadoras, a diferencia de los demas registros, cuya homogeneidad de traza implico una baja lagunaridad. Los resultados indican que la lagunaridad observada depende de la resolucion y profundidad radial de penetracion del metodo geofisico estudiado y aumenta sistematicamente en el siguiente orden: {delta}(RHOB) < {delta}(CALI) < {delta}(PEF) < {delta}(URAN) < {delta}(GR) < {delta}(NPHI) < {delta}(POTA) < {delta}(CGR) < {delta}(THOR) < {delta}(MSFL) < {delta}(DRHO) < {delta}(LLS) < {delta}(LLD).

  9. Field training

    International Nuclear Information System (INIS)

    Mumford, G.E.; Hadaway, E.H.

    1991-01-01

    Individualized, personal training can be used to increase an employee's awareness of the HSE program. Such training can stimulate personal commitment and provide personal skills that can be utilized for the benefit of the overall HSE effort. But, providing such training within our industry can be a difficult task due to the scheduling, travel arrangements, and cost associated with bringing employees from isolated, remote locations to centrally located training facilities. One method of overcoming these obstacles involves the use of field instructors to provide the training at the many, and varied number of individuals can be reached with minimal disruption to their work scheduling or to their time off. In fact, this type of on-site training is already used by some oil companies and drilling contractors with encouraging results. This paper describes one drilling contractor's experiences with such a training program. The results after eight years how that this program not only can provide and efficient, economical means of employee training, but also can have a direct application to employee motivation regarding a company's HSE effort

  10. Automatic Inspection of Co-Laminated Elements; Controle Automatique d'Elements Colamines; Avtomaticheskij kontrol' ul'trazvukom sovmestno prokatannykh ehlementov; Metodo para la Verificacion Automatica de Elementos Colaminados

    Energy Technology Data Exchange (ETDEWEB)

    Destribats, Marie-Therese [Centre d' Etudes Nucleaires de Saclay (France); Dory, J. [Realisations Ultrasoniques Meaux (S. et M.) (France)

    1965-09-15

    'un disque rotatif. Chaque traducteur est mis en service tous les 1/6 de tour par l'intermediaire de relais commandes par des secteurs aimantes. De la sorte, le pinceau ultrasonore decrit sur la surface de la plaque une serie d'arcs de cercle jointifs. La quantite d'energie transmise a travers la plaque est mesuree avec precision en chaque point. Le resultat de la mesure est applique a un enregistreur special qui donne une reproduction en vraie grandeur de l'element examine (le papier de l'enregistreur est de type ordinaire; l'inscription s'effectue au moyen de papier carbone). Sur l'enregistrement obtenu, les defauts apparaissent sous forme de taches foncees. L'appareillage peut fonctionner, soit en tout ou rien avec un seuil de marquage predetermine, soit en demi-teintes. Les traducteurs, dont la frequence peut varier de 3 a 15 MHz, sont excites par des impulsions breves. Les traducteurs utilisies, en titanate de baryum, ont un diametre de 3 mm. Le pas d'exploration est variable de 0,3 a 0,6 mm, la vitesse lineaire etant de 5 a 20 mm par seconde. L'ensemble peut recevoir des elements ayant les dimensions maximales suivantes: largeur 150 mm, longueur 2000 mm, epaisseur 25 mm. Les essais effectues jusqu'a ce jour ont permis de determiner des zones decollees de 0,5mm diametre dans de elements de 2 mm d'epaisseur. (author) [Spanish] Se describe en esta memoria un aparato automatico destinado a verificar, por un metodo ultrasoniso, la calidad de las vainas fabricadas con elementos colaminados. Estos elementos movidos por rodillos pasan bajo el haz ultrasonico sumergidos en una cuba de acero inoxidable llena de agua. Un reflector auxiliar permite utilizar los mismos transductores para la emision y la recepcion. La exploracion de las placas se lleva a cabo mediante seis transductores dispuestos en la periferia de un disco rotativo. Los transductores entran en funcion uno tras otro, cada 1/6 de vuelta, por intermedio de un sistema reles accionados por sectores imanados. De esta

  11. Research on Wide-field Imaging Technologies for Low-frequency Radio Array

    Science.gov (United States)

    Lao, B. Q.; An, T.; Chen, X.; Wu, X. C.; Lu, Y.

    2017-09-01

    Wide-field imaging of low-frequency radio telescopes are subject to a number of difficult problems. One particularly pernicious problem is the non-coplanar baseline effect. It will lead to distortion of the final image when the phase of w direction called w-term is ignored. The image degradation effects are amplified for telescopes with the wide field of view. This paper summarizes and analyzes several w-term correction methods and their technical principles. Their advantages and disadvantages have been analyzed after comparing their computational cost and computational complexity. We conduct simulations with two of these methods, faceting and w-projection, based on the configuration of the first-phase Square Kilometre Array (SKA) low frequency array. The resulted images are also compared with the two-dimensional Fourier transform method. The results show that image quality and correctness derived from both faceting and w-projection are better than the two-dimensional Fourier transform method in wide-field imaging. The image quality and run time affected by the number of facets and w steps have been evaluated. The results indicate that the number of facets and w steps must be reasonable. Finally, we analyze the effect of data size on the run time of faceting and w-projection. The results show that faceting and w-projection need to be optimized before the massive amounts of data processing. The research of the present paper initiates the analysis of wide-field imaging techniques and their application in the existing and future low-frequency array, and fosters the application and promotion to much broader fields.

  12. Neutron Investigation of Magnon Spectrum in Haematite; Etude du Spectre de Magnons dans l'Hematite, au Moyen des Neutrons; Nejtronnoe issledovanie spektra magnona v gematite; Estudio, por Metodos Neutronicos, del Espectro de Magnones en la Hematita

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrijevic, Z.; Rzany, H.; Todorovic, J.; Wanic, A. [Institute for Nuclear Physics Cracow (Poland)

    1965-04-15

    -Sign y 126 Degree-Sign , respectivamente. Un acuerdo satisfactorio entre la teoria y los datos experimentales disponibles se tiene cuando SJ{sub 1} = SJ{sub 2} = 5,1 meV. Ademas de la rama magnonica acustica, los calculos han revelado la existencia de una rama optica, pero el estudio de esta no pudo llevarse a cabo por el metodo de difraccion neutronica. (author) [Russian] byli provedeny v Vincha na reaktore RA s ispol'zovaniem kristallicheskogo nejtronnogo spektrometra. Rassejanie monohromaticheskih nejtronov ({lambda} = 1.314A) proizvodilos' na krupnom monokristalle gematita ({alpha}-Fe{sub 2}O{sub 3}). Issledovalis' uglovye raspredelenija neuprugo rassejannyh nejtronov. Dlja rjada razlichnyh nepravil'nyh uglov kristalla AO byla izmerena shirina G puchka rassejannyh nejtronov (tak nazyvaemogo konusa rassejanija). Jetot konus rassejanija byl pripisan javleniju poverhnostnogo rassejanija magnona vokrug tochki obratnoj reshetki [1,1,1] . Dlja rjada skorostej magnona byla rasschitana i sravnena s jeksperimental'nymi tochkami zavisimost' G ot nepravil'nogo ugla. Ustanovleno, chto velichina skorosti v napravlenii [111] ravna 25,5 11,0 km/sek. Byla obnaruzhena strukturnaja anizotropija dispersionnogo sootnoshenija magnona. Bylo najdeno, chto skorost' javljaetsja bolee vysokoj v napravlenijah rasprostranenija parallel'nyh osi [111] i chto kachestvenno ona horosho soglasuetsja s bolee rannimi izmerenijami (Riste i dr.) dajushhimi v = 38km/sek. Obnaruzhit' v akusticheskoj oblasti jenergii magnona sushhestvovanie razryva jenergeticheskoj krivoj Eg ne udalos'. Bylo rasschitano, chto velichina E dolzhna byt' nizhe 1 Mjev. Pri pomoshhi formalizma Uollase byli rasschitany dispersionnye sootnoshenija magnona v gematite. Pri jetom ishodili ije predpolozhenija, chto sushhestvujut dva ne stremjashhihsja k nulju integrala obmena J{sub 1} i J{sub 2}. J{sub 1} i J{sub 2} oznachajut svjaz' sverhobmennoj jenergii mezhdu spinami sosednih ionov zheleza, svjazannyh ionom kisloroda. Ugly svjazi

  13. A full-field transmission x-ray microscope for time-resolved imaging of magnetic nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Ewald, J.; Nisius, T.; Abbati, G.; Baumbach, S.; Overbuschmann, J.; Wilhein, T. [Institute for X-Optics (IXO), Hochschule Koblenz, Joseph-Rovan-Allee 2, 53424 Remagen (Germany); Wessels, P.; Wieland, M.; Drescher, M. [The Hamburg Centre for Ultrafast Imaging (CUI), University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Institut für Experimentalphysik, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Vogel, A. [Institut für Angewandte Physik, University of Hamburg, Jungiusstraße 11, 20355 Hamburg (Germany); Viefhaus, J. [Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, 22607 Hamburg (Germany); Meier, G. [The Hamburg Centre for Ultrafast Imaging (CUI), University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg (Germany)

    2016-01-28

    Sub-nanosecond magnetization dynamics of small permalloy (Ni{sub 80}Fe{sub 20}) elements has been investigated with a new full-field transmission microscope at the soft X-ray beamline P04 of the high brilliance synchrotron radiation source PETRA III. The soft X-ray microscope generates a flat-top illumination field of 20 μm diameter using a grating condenser. A tilted nanostructured magnetic sample can be excited by a picosecond electric current pulse via a coplanar waveguide. The transmitted light of the sample plane is directly imaged by a micro zone plate with < 65 nm resolution onto a 2D gateable X-ray detector to select one particular bunch in the storage ring that probes the time evolution of the dynamic information successively via XMCD spectromicroscopy in a pump-probe scheme. In the experiments it was possible to generate a homogeneously magnetized state in patterned magnetic layers by a strong magnetic Oersted field pulse of 200 ps duration and directly observe the recovery to the initial flux-closure vortex patterns.

  14. An Appraisal of Analytical Methods for Plutonium and their Applications to the Analysis of Nuclear Materials; Evaluation des Methodes Analytiques de Dosage du Plutonium et de Leur Application a l'Analyse des Matieres Nucleaires; Otsenka analiticheskikh metodov opredeleniya plutoniya i ikh primenenie dlya analiza yadernykh materialov; Metodos Analiticos de Determinacion del Plutonio y su Empleo en el Analisis de Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Milner, G. W.C.; Phillips, G. [Atomic Energy Research Establishment, Harwell, Berks. (United Kingdom)

    1966-02-15

    respectifs de la dissolution dans des melanges d'acides mineraux courants et de la dissolution faisant appel a des procedes de fusion, avec des exemples a l'appui. Les auteurs decrivent aussi les procedes utilises et les resultats obtenus, pour l'analyse des alliages Pu-U, Pu-Ce-Co et Pu-U-Mo, des oxydes et carbures de Pu-U, et des cermets de carbure de Pu-U contenant Fe, Mo et Cr. Ces matieres sont l'aboutissement de recherches metallurgiques destinees a mettre au point des combustibles nucleaires. (author) [Spanish] Para determinar el contenido de plutonio de los materiales nucleares existen diversos metodos. Si se trata de cantidades del orden del miligramo se pueden emplear la espectrofotometria diferencial por el color del Pu (III), la gravimetria basada en el PuO2{sub ,} si recuento gamma y metodos de oxidorreduccion como las valoraciones potenciometricas o amperimetricas y la culombiometria de potencial controlado. Si se trata de microgramos son preferibles el recuento alfa, la dilucion isotopica o las tecnicas polarograficas. Teniendo en cuenta que unos metodos son mas adecuados que otros para ciertos tipos de muestra, el analista tiene que resolver un dificil problema de seleccion a fin de obtener ios mejores resultados posibles. Los autores exponen las ventajas y las limitaciones puestas de manifiesto por los anos de experiencia en la A.E.R.E. y formulan observaciones acerca de la exactitud y la precision de los metodos, su sensibilidad y otras cuestiones de especial interes. Como algunos de esos metodos exigen la separacion previa del plutonio, los autores estudian el empleo de las tecnicas de intercambio anionico y de cromatografia en fase inversa, y en particular su conveniencia para el analisis de muestras radiactivas. Examinan los muchos problemas que han surgido al analizar por estos metodos, aleaciones, productos ceramicos y cermets de plutonio en diversos sistemas que contenian uranio, torio, hierro, cromo, molibdeno, cerio y cobalto. La memoria trata

  15. The Application of Various Nondestructive Testing Methods to Fuel Elements of the Orgel Type; Application des Differentes Methodes d'Essais Non Destructifs aux Elements Combustibles du Type Orgel; Primenenie razlichnykh nedestruktivnykh metodov ispytanij k toplivnym ehlementam tipa ''orgel''; Aplicacion de Distintos Metodos de Ensayo No Destructivo a los Elementos Combustibles de Tipo Orgel

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, P.; Jansen, J. [EURATOM, C.C.R., Ispra (Italy)

    1965-09-15

    methode a un capteur montre quelles sont les limites d'utilisation de ces deux methodes. Defauts transversaux; La methode a un capteur appliquee a cette recherche fait l'objet d'une breve description. Entrainement mecanique: Le memoire fait etat d'un banc mecanique, type laboratoire, pour la recherche des criteres d'essais et d'un banc de passage des tubes, de type semi-industriel, pour l'examen en continu avec enregistrement des defauts. Les difficultes rencontrees et les moyens misenceuvrepoury remediersont evoques. c) Tests par radiographie. Cette methode fera l'objet d'un memoire special; seuls sont indiques les resultats obtenus sur tubes de force ou sur tubes de gaines. d) Test divers Les test finaux sur elements combustibles complets peuvent se resumer en deux parties. Tests d'etancheite au moyen du test a l'helium developpe par la SOGEV. Un dispositif permet d'examiner simultanement 4 ou 6 elements combustibles ou separement 2 ou 3. Tests classiques de radiographie; l'accent est mis plus particulierement sur l'etude des soudures; on donne la marge des conditions experimentales pour obtenir une bonne definition. En conclusion, les auteurs presentent un projet de chaine de controle semi-industrielle avec les differentes possibilites de traitements et essaient de degager une certaine philosophie des tests non destructifs appliques aux elements combustibles. (author) [Spanish] La memoria presenta los distintos metodos empleados para deteccion de fallas (de tipo dimensional o estructural) en vainas de elementos combustibles. Los autores describen, asimismo, los ensayos finales con elementos combustibles completos, en particular radiografia de las soldaduras y pruebas de estanqueidad. Este tema se ha tratado ya en forma parcial. El estudio de las caracteristicas dimensionales de las vainas lisas de SAP (producto de aluminio sinterizado) ha sido objeto de trabajos bastante avanzados. La memoria examina en particular los siguientes temas: 1. Medicion de diametros internos

  16. An electric field in a gravitational field

    International Nuclear Information System (INIS)

    Harpaz, Amos

    2005-01-01

    The behaviour of an electric field in a gravitational field is analysed. It is found that due to the mass (energy) of the electric field, it is subjected to gravity and it falls in the gravitational field. This fall curves the electric field, a stress force (a reaction force) is created, and the interaction of this reaction force with the static charge gives rise to the creation of radiation

  17. Analysis of Radiation Field and Block Pattern for Optimal Size in Multileaf Collimator

    International Nuclear Information System (INIS)

    Ahn, Seoung Do; Yang, Kwang Mo; Yi, Byong Yong; Choi, Eun Kyong; Chang, Hye Sook

    1994-01-01

    The patterns of the conventional radiation treatment fields and their shielding blocks are analysed to determine the optimal dimension of the MultiLeaf Collimator (MLC) which is considered as an essential tool for conformal therapy. Total 1169 radiation fields from 303 patients (203 from Asan Medical center, 50 from Baek Hosp and 50 from Hanyang Univ. Hosp.) were analysed for this study. Weighted case selection treatment site (from The Korean Society of Therapeutic Radiology 1003). Ninety one percent of total fields have shielding blocks. Y axis is defined as leaf movement direction and it is assumed that MLC is installed on the cranial-caudal direction. The length of X axis were distributed from 4cm to 40cm (less than 21cm for 95% of cases), and Y axis from 5cm to 38cm (less than 22cm for 95% of cases). The shielding blocks extended to less than 6cm from center of the filed for 95% of the cases. Start length for ninety five percent of block is less than 10cm for X axis and 11cm for Y axis. Seventy six percent of shielding blocks could be placed by either X or Y axis direction, 7.9% only by Y axis, 5.1% only by X axis and it is reasonable to install MLC for Y direction. Ninety five percent of patients can be treated with coplanar rotation therapy without changing the collimator angle. Eleven percent of cases of cases were impossible to replace with MLC. Futher study of shielding should be larger than 21cm X 22cm. The MLC should be designed as a pair of 21 leaves with 1cm wide for an acceptable resolution and 17cm long to enable the leaf to overtravel at least 6cm from the treatment field center

  18. Quantized fields in external field. Pt. 2

    International Nuclear Information System (INIS)

    Bellissard, J.

    1976-01-01

    The case of a charged scalar field is considered first. The existence of the corresponding Green's functions is proved. For weak fields, as well as pure electric or scalar external fields, the Bogoliubov S-operator is shown to be unitary, covariant, causal up-to-a-phase. These results are generalised to a class of higher spin quantized fields, 'nicely' coupled to external fields, which includes the Dirac theory, and in the case of minimal and magnetic dipole coupling, the spin one Petiau-Duffin-Kemmer theory. (orig.) [de

  19. Dosimetric Comparison of Split Field and Fixed Jaw Techniques for Large IMRT Target Volumes in the Head and Neck

    International Nuclear Information System (INIS)

    Srivastava, Shiv P.; Das, Indra J.; Kumar, Arvind; Johnstone, Peter A.S.

    2011-01-01

    Some treatment planning systems (TPSs), when used for large-field (>14 cm) intensity-modulated radiation therapy (IMRT), create split fields that produce excessive multiple-leaf collimator segments, match-line dose inhomogeneity, and higher treatment times than nonsplit fields. A new method using a fixed-jaw technique (FJT) forces the jaw to stay at a fixed position during optimization and is proposed to reduce problems associated with split fields. Dosimetric comparisons between split-field technique (SFT) and FJT used for IMRT treatment is presented. Five patients with head and neck malignancies and regional target volumes were studied and compared with both techniques. Treatment planning was performed on an Eclipse TPS using beam data generated for Varian 2100C linear accelerator. A standard beam arrangement consisting of nine coplanar fields, equally spaced, was used in both techniques. Institutional dose-volume constraints used in head and neck cancer were kept the same for both techniques. The dosimetric coverage for the target volumes between SFT and FJT for head and neck IMRT plan is identical within ±1% up to 90% dose. Similarly, the organs at risk (OARs) have dose-volume coverage nearly identical for all patients. When the total monitor unit (MU) and segments were analyzed, SFT produces statistically significant higher segments (17.3 ± 6.3%) and higher MU (13.7 ± 4.4%) than the FJT. There is no match line in FJT and hence dose uniformity in the target volume is superior to the SFT. Dosimetrically, SFT and FJT are similar for dose-volume coverage; however, the FJT method provides better logistics, lower MU, shorter treatment time, and better dose uniformity. The number of segments and MU also has been correlated with the whole body radiation dose with long-term complications. Thus, FJT should be the preferred option over SFT for large target volumes.

  20. Data Evaluation Problems in the Pulsed Neutron Source Method; Problemes d'Evaluation des Donnees dans les Applications de la Methode de la Source Pulsee; Problemy otsenki dannykh pri primenenii metoda istochnika impul'snykh nejtronov; Problemas de Evaluacion de Datos en el Metodo de la Fuente de Neutrones Pulsados

    Energy Technology Data Exchange (ETDEWEB)

    Pal, L.; Bod, L.; Szatmary, Z. [Central Research Institute for Physics, Hungarian Academy of Sciences, Budapest (Hungary)

    1965-08-15

    moyen de transport dans de nombreuses matieres hydrogenees. (author) [Spanish] Desde hace mas de diez anos se viene empleando el metodo de los neutrones pulsados para determinar los parametros de difusion de los neutrones termicos. Este metodo ha resultado especialmente idoneo para el estudio de los moderadores hidrogenados. Los autores dan los resultados de las mediciones hechas en agua, benceno, tolueno, xileno, ciclohexano, n-hexano y difenilo, y examinan los metodos para evaluar con el minimo error los parametros de difusion de interes partiendo de los datos obtenidos en las mediciones. Se examina detenidamente, tanto en el plano teorico como en el experimental, el efecto de tiempo de vuelo que se manifiesta por razones tecnicas cuando se investigan moderadores a elevadas temperaturas, y que influye en el valor de la constante de desintegracion, y se exponen las condiciones geometricas en que se ha de operar para obtener resultados satisfactorios. Los autores determinan tambien el efecto que sobre la constante de desintegracion ejerce el tiempo muerto del detector neutronico y del amplificador, y demuestran que es despreciable cuando [i(t) {tau}]{sup 2} << 1, siendo i/t/dt el numero de neutrones detectados en el intervalo de tiempo/t, t + dt/, y {tau} el tiempo muerto. Se evaluo la constante de desintegracion empleando el metodo de la maxima probabilidad. Para determinar inequivocamente la funcion de probabilidad, se eligio un analizador multicanal que acumulaba como maximo una sola senal por ciclo de analisis y por canal. Se comprobo que la incorporacion del parametro caracteristico del fondo a la funcion de probabilidad tiene primordial importancia. Los parametros de la funcion de maxima probabilidad se evaluaron en una calculadora aplicando el metodo de iteracion de Newton. Cuando no se tiene debidamente en cuenta el fondo, este puede causar una mayor contaminacion aparente de armonicos, la cual, a su vez, puede interpretarse como un fondo aparente. Por ello es

  1. Gravitation and vacuum field

    International Nuclear Information System (INIS)

    Tevikyan, R.V.

    1986-01-01

    This paper presents equations that describe particles with spins s = 0, 1/2, 1 completely and which also describe 2s + 2 limiting fields as E → ∞. It is shown that the ordinary Hilbert-Einstein action for the gravitation field must be augmented by the action for the Bose vacuum field. This means that one must introduce in the gravitational equations a cosmological term proportional to the square of the strength of the Bose vacuum field. It is shown that the theory of gravitation describes three realities: matter, field, and vacuum field. A new form of matter--the vacuum field--is introduced into field theory

  2. Fractal vector optical fields.

    Science.gov (United States)

    Pan, Yue; Gao, Xu-Zhen; Cai, Meng-Qiang; Zhang, Guan-Lin; Li, Yongnan; Tu, Chenghou; Wang, Hui-Tian

    2016-07-15

    We introduce the concept of a fractal, which provides an alternative approach for flexibly engineering the optical fields and their focal fields. We propose, design, and create a new family of optical fields-fractal vector optical fields, which build a bridge between the fractal and vector optical fields. The fractal vector optical fields have polarization states exhibiting fractal geometry, and may also involve the phase and/or amplitude simultaneously. The results reveal that the focal fields exhibit self-similarity, and the hierarchy of the fractal has the "weeding" role. The fractal can be used to engineer the focal field.

  3. Electric Field Imaging

    Data.gov (United States)

    National Aeronautics and Space Administration — NDE historically has focused technology development in propagating wave phenomena with little attention to the field of electrostatics and emanating electric fields....

  4. How fields vary.

    Science.gov (United States)

    Krause, Monika

    2018-03-01

    Field theorists have long insisted that research needs to pay attention to the particular properties of each field studied. But while much field-theoretical research is comparative, either explicitly or implicitly, scholars have only begun to develop the language for describing the dimensions along which fields can be similar to and different from each other. In this context, this paper articulates an agenda for the analysis of variable properties of fields. It discusses variation in the degree but also in the kind of field autonomy. It discusses different dimensions of variation in field structure: fields can be more or less contested, and more or less hierarchical. The structure of symbolic oppositions in a field may take different forms. Lastly, it analyses the dimensions of variation highlighted by research on fields on the sub- and transnational scale. Post-national analysis allows us to ask how fields relate to fields of the same kind on different scales, and how fields relate to fields on the same scale in other national contexts. It allows us to ask about the role resources from other scales play in structuring symbolic oppositions within fields. A more fine-tuned vocabulary for field variation can help us better describe particular fields and it is a precondition for generating hypotheses about the conditions under which we can expect to observe fields with specified characteristics. © London School of Economics and Political Science 2017.

  5. Magnetic Field Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Calculator will calculate the total magnetic field, including components (declination, inclination, horizontal intensity, northerly intensity,...

  6. Magnetic field reconnexion in a sheared field

    International Nuclear Information System (INIS)

    Ugai, M.

    1981-01-01

    A nonlinear development of the Petschek mode in a sheared magnetic field where there is a field component Bsub(z) along an X line is numerically studied. It is found that finite-amplitude intermediate waves, adjacent to the slow shock, may eventually stand in the quasi-steady configuration; on the other hand, the fundamental characteristics of the Petschek-mode development are scarcely influenced, either qualitatively or quantitatively, by the Bsub(z) field. (author)

  7. Wake fields and wake field acceleration

    International Nuclear Information System (INIS)

    Bane, K.L.F.; Wilson, P.B.; Weiland, T.

    1984-12-01

    In this lecture we introduce the concepts of wake fields and wake potentials, examine some basic properties of these functions, show how they can be calculated, and look briefly at a few important applications. One such application is wake field acceleration. The wake field accelerator is capable of producing the high gradients required for future very high energy e + e - linear colliders. The principles of wake field acceleration, and a brief description of experiments in progress in this area, are presented in the concluding section. 40 references, 27 figures

  8. Boundary element analysis of stress due to thermal shock loading or reactor pressure vessel nozzle; Napetostna analiza pri nestacionarni termicni obremenitvi cevnega prikljucka reaktorske tlacne posode z metodo robnih elementov

    Energy Technology Data Exchange (ETDEWEB)

    Kramberger, J; Potrc, I [Tehniska fakulteta, Maribor (Yugoslavia)

    1989-07-01

    Apart from being exposed to the primary loading of internal pressure and steady temperature field, the reactor pressure vessel is also subject to various thermal transients (thermal shocks). Theoretical and experimental stress analyses show that severe material stresses occur in the nozzle area of the pressure vessel which may lead to defects (cracks). It has been our aim to evaluate these stresses by the use of the Boundary Element method. (author)

  9. On Jacobi-fields

    International Nuclear Information System (INIS)

    Bruening, E.

    1981-01-01

    The concept of a Jacobi-field is introduced as such a field for which the field-operators have the form of a generalized Jacobi-matrix with respect to the n-field-sector decomposition of the state-space. It is argued that the class of Jacobi-fields is of interest for relativistic quantum field theory for two reasons: (a) Jacobi-fields allow a direct association of particles (charges etc.) with fields. The concept of (generalized) creation- and annihilation-operators is thus available. (b) Jacobi-fields belong to that class of fields which can be characterized in terms of finitely many vacuum expectation values. A characterization of Jacobi-fields in terms of continuity and hermiticity properties of their system of vacuum expectation values is derived. Furthermore it is argued that all examples of relativistic quantum fields in a four-dimensional space-time are Jacobi-fields. This is evident for generalized free fields and Wick-powers of free fields, but is also true for a class of generalized Wick-powers of generalized free fields. (Auth.)

  10. Field Trips. Beginnings Workshop.

    Science.gov (United States)

    Cartwright, Sally; Aronson, Susan S.; Stacey, Susan; Winbush, Olga

    2001-01-01

    Five articles highlight benefits and organization of field trips: (1) "Field Trips Promote Child Learning at Its Best"; (2) "Planning for Maximum Benefit, Minimum Risk"; (3) "Coaching Community Hosts"; (4) "The Story of a Field Trip: Trash and Its Place within Children's Learning and Community"; and (5) "Field Trip Stories and Perspectives" (from…

  11. Field Campaign Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Voyles, J. W. [DOE ARM Climate Research Facility, Washington, DC (United States); Chapman, L. A. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-12-01

    This document establishes a common set of guidelines for the Atmospheric Radiation Measurement (ARM) Climate Research Facility for planning, executing, and closing out field campaigns. The steps that guide individual field campaigns are described in the Field Campaign Tracking System and are specifically tailored to meet the scope of each field campaign.

  12. The Galactic magnetic fields

    International Nuclear Information System (INIS)

    Han Jinlin

    2006-01-01

    A good progress has been made on studies of Galactic magnetic fields in last 10 years. I describe what we want to know about the Galactic magnetic fields, and then review we current knowledge about magnetic fields in the Galactic disk, the Galactic halo and the field strengths. I also listed many unsolved problems on this area

  13. Industrial Ultrasonic Inspection of Stainless-Steel Claddings for the EL4 Reactor; Controle Industriel par Ultrasons des Gaines en Acier Inoxydable du Reacteur EL4; Promyshlennyj kontrol' obolochechnykh trub iz nerzhaveyushchej stali reaktora dlya EL4 s pomoshch'yu ul'trazvukovogo metoda; Metodos Ultrasonicos para Control Industrial de las Vainas de Acero Inoxidable del Reactor EL4

    Energy Technology Data Exchange (ETDEWEB)

    Prot, A. C.; Foulquoer, H. E.; Peyrot, J. P. [Centre d' Etudes Nucleaires de Saclay (France)

    1965-09-15

    del metodo a utilizar representa un proceso delicado, cuyas consideraciones fundamentales se exponen en el presente trabajo. Una vez elegido el metodo y puesto a punto en el laboratorio, surgen dos nuevos problemas: Transposicion a escala industrial. Necesidad de tener siempre presente la calidad que puede alcanzarse en la industria, en relacion con normas de aceptacion definidas de manera mas o menos arbitraria. En la practica, ello obliga a realizar un estudio estadistico sobre partidas de tubos de diversos origenes y clasificarlos teniendo en cuenta umbrales de aceptacion de distintos grados de severidad. Como se ve en el trabajo, el numero de tubos a controlar es muy superior al previsto inicialmente. Este hecho indujo a estudiar una maquina de control automatico, capaz de satisfacer al mismo tiempo las exigencias de la cantidad y las propias del tipo de control seleccionado; estas ultimas son por lo general de orden mecanico y requieren una construccion especialmente esmerada. El conjunto de estas consideraciones llevo a concebir una maquina capaz de satisfacer sin dificultad las necesidades de una cadena de fabricacion'de elementos combustibles. Las posibilidades de esta maquina estan estrechamente ligadas a las caracteristicas del material descontrol escogido, sobre todo al rendimiento de los circuitos electronicos correspondientes a los aparatos de control por metodos ultrasonicos y al de los transductores utilizados. Se deduce del presente estudio, por otra parte, que el material corriente no responde al problema sino de manera muy imperfecta, y que se debe encarar desde ya el proyecto de un aparato especial para este tipo de control. (author) [Russian] Uluchshenie rabochih harakteristik reaktorov trebuet primenenija tshhatel'no razrabotannyh i strogo kontroliruemyh materialov. Odnim iz aspektov jetogo kontrolja javljaetsja kachestvo ispol'zuemyh pokrytij dlja trub, mehanicheskoe sostojanie kotoryh predstavljaet soboj sushhestvennyj faktor rentabel

  14. The Role of Non-Destructive Testing in the Los Alamos Reactor Programme; Role des Essais Non Destructifs dans le Programme de Reacteurs de los Alamos; Rol' nedestruktivnykh ispytanij materialov v Los-Alamosskoj reaktornoj programme; Papel de los Metodos de Ensayo No Destructivo en el Programa de Reactores de Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Tenney, G. H. [University of California, Los Alamos Scientific Laboratory, Los Alamos, NM (United States)

    1965-10-15

    temperature UHTREX, actuellement en construction, on a etudie par microiadiogiaphie et au moyen de microscopes electroniques des grains de carbure d'uranium enrobes de carbone pyrolytique, d'un diametre de 150 {mu}m, pour evaluer la translocation de l'uranium en fonction de la temperature. On determine la quantite et l'uniformite de la charge d'uranium dans les elements au graphite d'UHTREX au moyen de compteurs a scintillation specialement concus. Environ 90% des travaux effectues a ce sujet n'ont encore fait l'objet d'aucune publication. (author) [Spanish] El Laboratorio Cientifico de Los Alamos, explotado por la Universidad de California por encargo de la Comision de Energia Atomica de los Estados Unidos, viene ocupandose desde hace mas de veinte afios del proyecto, diseno y construccion de reactores nucleares de cuatro tipos generales; a saber, de investigacion, de potencia, de propulsion espacial y para conjuntos criticos. El llamado Grupo de ensayos no destructivos colabora practicamente en todas las actividades y proyectos del laboratorio. En la presente memoria se exponen algunos de los metodos de ensayo no destructivo y sus aplicaciones, establecidos para uso en el programa de reactores. El programa LAPRE (Los Alamos Power Reactor Experiment) se basa en el empleo de una solucion de fosfato de uranio a alta temperatura. La solucion es muy corrosiva y todas las piezas que entren en contacto con ella deben ir revestidas de oro. Durante el proceso de produccion de chapa de oro laminada a partir de lingotes, se han utilizado procedimientos radiograficos especiales para inspeccionar el metal. Las juntas soldadas se examinaron del mismo modo, y ademas se establecio un metodo para comprobar la presencia de impurezas incrustadas en la superficie de la chapa de oro. El concepto fundamental en que se basa el programa LAMPRE (Los Alamos Molten Plutonium Reactor Experiment) es la utilizacion como combustible de plutonio metalico liquido en vez de solido. El combustible esta

  15. Gauge fields in a torsion field

    International Nuclear Information System (INIS)

    Rosu, Ion

    2004-01-01

    In this paper we analyse the motion and the field equations in a non-null curvature and torsion space. In this 4-n dimensional space, the connection coefficients are γ bc a = 1/2S bc a + 1/2T bc a, where S bc a is the symmetrical part and T bc a are the components of the torsion tensor. We will consider that all the fields depend on x = x α , α = 1,2,3,4 and do not depend on y = y k , k=1,2,...,n. The factor S bc a depends on the components of the metric tensor g αβ (x) and on the gauge fields A ν s 0 (x) and the components of the torsion depend only on the gauge fields A ν s 0 (x). We take into consideration the particular case for which the geodesic equations coincide with the motion equations in the presence of the gravitational and the gauge fields. In this case the field equations are Einstein equations in a 4-n dimensional space. We show that both the geodesic equations and the field equations can be obtained from a variational principle. (author)

  16. Comportamiento de Laminaciones Coplanares y No Coplanares en Acero API5L X52 Simuladas mediante Elementos Finitos Behavior of Coplanar and Non-Coplanar Laminations in API5L X52 Steel Simulated by Finite Elements

    OpenAIRE

    Alberto Servin; Jorge L González; Alfredo Morales

    2009-01-01

    Se determina el comportamiento mecánico de laminaciones simples y escalonadas modeladas por elementos finitos en condiciones no lineales de esfuerzo-deformación, para comprender la secuencia de la interacción de los campos de esfuerzos en los extremos de la grietas. Se estableció una matriz de simulación variando la extensión circunferencial de las laminaciones, con espesor del tubo de 610mm de diámetro, con separación vertical y horizontal para el caso de laminaciones escalonadas. Se determi...

  17. Ultra wideband coplanar waveguide fed spiral antenna for humanitarian demining

    DEFF Research Database (Denmark)

    Thaysen, Jesper; Jakobsen, Kaj Bjarne; Appel-Hansen, Jørgen

    2000-01-01

    to 1 bandwidth with a return loss better than 10 dB from 0.4 to 3.8 GHz is presented. A wideband balun covering the frequency range of the antenna was developed. The constructed spiral antenna is very useful in a stepped frequency ground penetrating radar for humanitarian demining due to the very...

  18. Nonlinearity in superconducting titanium nitride coplanar waveguide resonators

    International Nuclear Information System (INIS)

    Neilinger, P.; Trgala, M.; Hrebikova, I.; Mikula, M.; Zahoran, M.; Truchly, M.; Grajcar, M.; Leporis, M.

    2012-01-01

    In this paper we present fabrication and characterization of superconducting CPW TiN resonator at 20 and 300 nm film thickness. Further we demonstrate strong nonlinearity in thin TiN resonators. (authors)

  19. RESONANCE TRAPPING IN PROTOPLANETARY DISKS. I. COPLANAR SYSTEMS

    International Nuclear Information System (INIS)

    Lee, Aaron T.; Thommes, Edward W.; Rasio, Frederic A.

    2009-01-01

    Mean-motion resonances (MMRs) are likely to play an important role both during and after the lifetime of a protostellar gas disk. We study the dynamical evolution and stability of planetary systems containing two giant planets on circular orbits near a 2:1 resonance and closer. We find that by having the outer planet migrate inward, the two planets can capture into either the 2:1, 5:3, or 3:2 MMR. We use direct numerical integrations of ∼1000 systems in which the planets are initially locked into one of these resonances and allowed to evolve for up to ∼10 7 yr. We find that the final eccentricity distribution in systems which ultimately become unstable gives a good fit to observed exoplanets. Next, we integrate ∼500 two-planet systems in which the outer planet is driven to continuously migrate inward, resonantly capturing the inner planet; the systems are evolved until either instability sets in or the planets reach the star. We find that although the 5:3 resonance rapidly becomes unstable under migration, the 2:1 and 3:2 are very stable. Thus the lack of observed exoplanets in resonances closer than 2:1, if it continues to hold up, may be a primordial signature of the planet formation process.

  20. A Nafion -based co-planar electrode amperometric sensor for ...

    Indian Academy of Sciences (India)

    Administrator

    The methanol detector could be operated both in a nitrogen stream and (in what is essential for practical applications) in an air atmosphere too, with estimated detection limits of 1⋅2 and .... adsorption/desorption are not clear but this is a common finding of the enormous Pt/Nafion. ® litera- ture. For example, Mitsushima et al.

  1. Exterior Companions to Hot Jupiters Orbiting Cool Stars Are Coplanar

    Science.gov (United States)

    Becker, Juliette C.; Vanderburg, Andrew; Adams, Fred C.; Khain, Tali; Bryan, Marta

    2017-12-01

    The existence of hot Jupiters has challenged theories of planetary formation since the first extrasolar planets were detected. Giant planets are generally believed to form far from their host stars, where volatile materials like water exist in their solid phase, making it easier for giant planet cores to accumulate. Several mechanisms have been proposed to explain how giant planets can migrate inward from their birth sites to short-period orbits. One such mechanism, called Kozai-Lidov migration, requires the presence of distant companions in orbits inclined by more than ˜40° with respect to the plane of the hot Jupiter’s orbit. The high occurrence rate of wide companions in hot-Jupiter systems lends support to this theory for migration. However, the exact orbital inclinations of these detected planetary and stellar companions is not known, so it is not clear whether the mutual inclination of these companions is large enough for the Kozai-Lidov process to operate. This paper shows that in systems orbiting cool stars with convective outer layers, the orbits of most wide planetary companions to hot Jupiters must be well aligned with the orbits of the hot Jupiters and the spins of the host stars. For a variety of possible distributions for the inclination of the companion, the width of the distribution must be less than ˜20° to recreate the observations with good fidelity. As a result, the companion orbits are likely well aligned with those of the hot Jupiters, and the Kozai-Lidov mechanism does not enforce migration in these systems.

  2. Engineering field theory

    CERN Document Server

    Baden Fuller, A J

    2014-01-01

    Engineering Field Theory focuses on the applications of field theory in gravitation, electrostatics, magnetism, electric current flow, conductive heat transfer, fluid flow, and seepage.The manuscript first ponders on electric flux, electrical materials, and flux function. Discussions focus on field intensity at the surface of a conductor, force on a charged surface, atomic properties, doublet and uniform field, flux tube and flux line, line charge and line sink, field of a surface charge, field intensity, flux density, permittivity, and Coulomb's law. The text then takes a look at gravitation

  3. Ambient Field Analysis at Groningen Gas Field

    Science.gov (United States)

    Spica, Z.; Nakata, N.; Beroza, G. C.

    2016-12-01

    We analyze continuous ambient-field data at Groningen gas field (Netherlands) through cross-correlation processing. The Groningen array is composed of 75 shallow boreholes with 6 km spacing, which contain a 3C surface accelerometer and four 5-Hz 3C borehole geophones spaced at 50 m depth intervals. We successfully retrieve coherent waves from ambient seismic field on the 9 components between stations. Results show high SNR signal in the frequency range of 0.125-1 Hz, and the ZZ, ZR, RZ, RR and TT components show much stronger wave energy than other components as expected. This poster discuss the different type of waves retrieved, the utility of the combination of borehole and surface observations, future development as well as the importance to compute the 9 components of the Green's tensor to better understand the wave field propriety with ambient noise.

  4. Implementation of a method for patient-specific IMRT treatment verification using dynalog files; Aplicacion de un metodo para la verificacion de tratamientos de imrt sobre la anatomia del paciente utilizando archivos dynalog

    Energy Technology Data Exchange (ETDEWEB)

    Calama Santiago, J. A.; Infante Utrilla, M. A.; Lavado Rodriguez, M. E.

    2011-07-01

    The aim of this work is to implement a simple method of intensity modulated radiation therapy (IMRT) verification on the patient anatomy using dynalog files. Monitor units (MU) fraction and leaf positions, both planned and actually positioned during treatment, are sampled every 55 ms and stored in these files. This information was used in the treatment planning system to reconstruct the given fluence and to recalculate the absorbed dose in the patients CT, comparing absorbed dose distributions and histograms with those initially planned. Differences mainly appeared in areas with high absorbed dose gradients at the beginning and at the end of the radiation fields. These differences were lower than 3% in absorbed dose for most cases. No significant differences were found on dose-volume histograms. With proper linac and multileaf collimator commissioning, and a more stringent linac, treatment planning and record and verify system quality assurance program, this procedure allows patient-specific IMRT treatment verification, unlike conventional methods. (Author) 15 refs.

  5. Use of the 3DVH Software as a complementary method of IMRT pretreatment evaluation; Utilizacao do Software 3DVH como metodo complementar de avaliacao de pre-tratamento de IMRT

    Energy Technology Data Exchange (ETDEWEB)

    Lyra, Jesse G.P.; Bruning, Fabio F.; Funchal, Melissa; Toledo, Hugo V.; Bornatto, Pricila; Fernandes, Tatiane C.O., E-mail: jesse_lyra@hotmail.com [Hospital Erasto Gaertner / Liga Paranaense de Combate ao Cancer (LPCC), Departamento de Radioterapia, Curitiba, PR (Brazil)

    2013-04-15

    The aim of this study is to compare the method of treatment planning evaluation for IMRT using the gamma index to the method of the 3DVH Software. The 3DVH Software was used with the MapCheck2 detector 2D array under a 6MV x-ray beam of linear accelerator equipped with 120 leafs MLC. Nine treatment plans of prostate patients chose randomly and fully anonimatize were performed in the Eclipse planning system, using the AAA calculation algorithm in IMRT sliding window technique. These plans were approved and treated according to the gamma analysis criteria of the institution. The comparisons were made in absolute dose and normalized at maximum dose for each field and then with the 3DVH Software the Dmax, Dmean, D15%, D25%, D35% and D50% parameters for the bladder and rectum, Dmean for the bulb, Dmax for the femur and D95% for the PTV were evaluated. In the planar analysis by field, the plans studied had a minimum of 97.5% approval. The PTV-related differences have relative variation from 1.3 to 2.2%, that is, greater coverage than expected for this structure. For the organs at risk, the relative differences observed were between -5.3 to 25.8%, which could result in a non-approved plan if these variations are close to the clinical tolerances of the OAR. The results show that even a plan compatible with greater than or equal to 95% of the points, the gamma analysis does not give enough information if this plan can or cannot be approved for treatment and that there is a need for more detailed verification of the plan which considers not only the planar evaluation, but also the evaluation of the DVH measured, and the 3DVH Software proved be adequate for this analysis. (author)

  6. New processing techniques for radioisotopes at Oak Ridge National Laboratory; Production de radioisotopes: nouvelles techniques employees au Laboratoire national d'Oak Ridge; Novye tekhnologicheskie metody polucheniya radioizotopov v Okridzhskoj natsional'noj laboratorii; Nuevos metodos de preparacion de radioisotopos aplicados en el Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Butler, T A; Lamb, E; Rupp, A F [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-01-15

    une activite de 235 c/g. La poudre a ete comprimee en pastilles, que l'on a ensuite agglomerees pour leur donner une consistance ceramique. Le prometheum-147 a ete produit en quantites de l'ordre du kilocurie par combinaison des techniques de precipitation et d'echanges d'ions. Un procede d'extraction par solvant pour separer le prometheum-147 d'autres terres rares a ete experimente sur de tres faibles quantites. Quelques grammes de technetium-99 ont ete recuperes dans les produits de fission des effluents par precipitation et extraction par solvant combinees. Le technetium avait une purete chimique superieure a 99,9% et une purete radiochimique superieure a 99,99%. La purification du strontium-90 par elimination des contaminants les plus importants, a l'aide d'un systeme d'extraction continu par solvant, a ete demontree sur de tres petites quantites. En partant d'un produit contenant 95% de calcium inerte, on a obtenu du strontium a 98% de purete. On a ensuite traite le strontium-90 pour obtenir des elements ceramiques de titanate de strontium. (author) [Spanish] Entre los adelantos mas recientes introducidos en el programa de preparacion de radioisotopos del Oak Ridge National Laboratory se cuenta el desarrollo de nuevos metodos y el mejoramiento de procedimientos ya establecidos para la obtencion de cerio-144, promecio-147, tecnecio-99 y estroncio-90. Se ha producido experimentalmente cerio-144 en escala de los kiloeuries. Se recupero mas del 98% de cerio con una pureza superior al 99%. Este cerio se siguio purificando hasta obtener oxido de cerio puro en forma pulverulenta de actividad especifica igual a 235 e/g. Este polvo se comprimio en pastillas y se sinterizo para obtener un material ceramico denso. El promecio-147 se obtuvo en cantidades de kiloeuries aplicando un metodo combinado de precipitacion e intercambio ionico. Se ensayo la extraccion de vestigios de elementos con disolventes para separar el promecio-147 de otras tierras raras. Gracias a una

  7. Covariant Noncommutative Field Theory

    Energy Technology Data Exchange (ETDEWEB)

    Estrada-Jimenez, S [Licenciaturas en Fisica y en Matematicas, Facultad de Ingenieria, Universidad Autonoma de Chiapas Calle 4a Ote. Nte. 1428, Tuxtla Gutierrez, Chiapas (Mexico); Garcia-Compean, H [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN P.O. Box 14-740, 07000 Mexico D.F., Mexico and Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Monterrey Via del Conocimiento 201, Parque de Investigacion e Innovacion Tecnologica (PIIT) Autopista nueva al Aeropuerto km 9.5, Lote 1, Manzana 29, cp. 66600 Apodaca Nuevo Leon (Mexico); Obregon, O [Instituto de Fisica de la Universidad de Guanajuato P.O. Box E-143, 37150 Leon Gto. (Mexico); Ramirez, C [Facultad de Ciencias Fisico Matematicas, Universidad Autonoma de Puebla, P.O. Box 1364, 72000 Puebla (Mexico)

    2008-07-02

    The covariant approach to noncommutative field and gauge theories is revisited. In the process the formalism is applied to field theories invariant under diffeomorphisms. Local differentiable forms are defined in this context. The lagrangian and hamiltonian formalism is consistently introduced.

  8. Covariant Noncommutative Field Theory

    International Nuclear Information System (INIS)

    Estrada-Jimenez, S.; Garcia-Compean, H.; Obregon, O.; Ramirez, C.

    2008-01-01

    The covariant approach to noncommutative field and gauge theories is revisited. In the process the formalism is applied to field theories invariant under diffeomorphisms. Local differentiable forms are defined in this context. The lagrangian and hamiltonian formalism is consistently introduced

  9. Understanding Vector Fields.

    Science.gov (United States)

    Curjel, C. R.

    1990-01-01

    Presented are activities that help students understand the idea of a vector field. Included are definitions, flow lines, tangential and normal components along curves, flux and work, field conservation, and differential equations. (KR)

  10. Magnetic Field Grid Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Properties Calculator will computes the estimated values of Earth's magnetic field(declination, inclination, vertical component, northerly...

  11. Gauge field copies

    International Nuclear Information System (INIS)

    Bollini, C.G.; Giambiagi, J.J.; Tiomno, J.

    1979-01-01

    The construction of field strength copies without any gauge constraint is discussed. Several examples are given, one of which is not only a field strength copy but also (at the same time) a 'current copy'. (author) [pt

  12. Cosmological magnetic fields - V

    Indian Academy of Sciences (India)

    Magnetic fields seem to be everywhere that we can look in the universe, from our own ... The field tensor is observer-independent, while the electric and magnetic .... based on string theory [11], in which vacuum fluctuations of the field are ...

  13. Unified field theory

    International Nuclear Information System (INIS)

    Prasad, R.

    1975-01-01

    Results of researches into Unified Field Theory over the past seven years are presented. The subject is dealt with in chapters entitled: the choice of affine connection, algebraic properties of the vector fields, field laws obtained from the affine connection based on the path integral method, application to quantum theory and cosmology, interpretation of physical theory in terms of geometry. (U.K.)

  14. Politics of aviation fields

    Science.gov (United States)

    Vivent, Jacques

    1922-01-01

    In short, the "politics of aviation" lies in a few propositions: the need of having as large a number of fields as possible and of sufficient area; the utilization of the larger part of the existing military fields; the selection of uncultivated or unproductive fields, whenever technical conditions permit; ability to disregard (save in exceptional cases) objections of an agricultural nature.

  15. Finite discrete field theory

    International Nuclear Information System (INIS)

    Souza, Manoelito M. de

    1997-01-01

    We discuss the physical meaning and the geometric interpretation of implementation in classical field theories. The origin of infinities and other inconsistencies in field theories is traced to fields defined with support on the light cone; a finite and consistent field theory requires a light-cone generator as the field support. Then, we introduce a classical field theory with support on the light cone generators. It results on a description of discrete (point-like) interactions in terms of localized particle-like fields. We find the propagators of these particle-like fields and discuss their physical meaning, properties and consequences. They are conformally invariant, singularity-free, and describing a manifestly covariant (1 + 1)-dimensional dynamics in a (3 = 1) spacetime. Remarkably this conformal symmetry remains even for the propagation of a massive field in four spacetime dimensions. We apply this formalism to Classical electrodynamics and to the General Relativity Theory. The standard formalism with its distributed fields is retrieved in terms of spacetime average of the discrete field. Singularities are the by-products of the averaging process. This new formalism enlighten the meaning and the problem of field theory, and may allow a softer transition to a quantum theory. (author)

  16. ZEPHYR - poloidal field system

    International Nuclear Information System (INIS)

    Seidel, U.

    1982-04-01

    The basics of the poloidal field system of the ZEPHYR experiment are considered. From the physical data the requirements for the poloidal field are derived. Hence an appropriate coil configuration consisting of coil locations and corresponding currents is obtained. A suitable electrical circuit feeding the coils is described. A preliminary assessment of the dynamic control of the poloidal field system is given. (orig.)

  17. Magnetic field line Hamiltonian

    International Nuclear Information System (INIS)

    Boozer, A.H.

    1985-02-01

    The basic properties of the Hamiltonian representation of magnetic fields in canonical form are reviewed. The theory of canonical magnetic perturbation theory is then developed and applied to the time evolution of a magnetic field embedded in a toroidal plasma. Finally, the extension of the energy principle to tearing modes, utilizing the magnetic field line Hamiltonian, is outlined

  18. Omnigenous magnetic fields

    International Nuclear Information System (INIS)

    Stupakov, G.V.

    1982-01-01

    In omnigenous magnetic fields particles' drift surfaces coincide with plasma magnetic surfaces. In this paper we formulate equations of omnigenous magnetic fields in natural curvilinear coordinates. An analysis of fields which are omnigenous only in the paraxial approximation is presented. (author)

  19. Far field acceleration

    International Nuclear Information System (INIS)

    Fernow, R.C.

    1995-07-01

    Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail

  20. Cosmic Magnetic Fields

    Science.gov (United States)

    Sánchez Almeida, J.; Martínez González, M. J.

    2018-05-01

    Magnetic fields play an important role in many astrophysical processes. They are difficult to detect and characterize since often their properties have to be inferred through interpreting the polarization of the light. Magnetic fields are also challenging to model and understand. Magnetized plasmas behave following highly non-linear differential equations having no general solution, so that every astrophysical problem represents a special case to be studied independently. Hence, magnetic fields are often an inconvenient subject which is overlooked or simply neglected (the elephant in the room, as they are dubbed in poster of the school). Such difficulty burdens the research on magnetic fields, which has evolved to become a very technical subject, with many small disconnected communities studying specific aspects and details. The school tried to amend the situation by providing a unifying view of the subject. The students had a chance to understand the behavior of magnetic fields in all astrophysical contexts, from cosmology to the Sun, and from starbursts to AGNs. The school was planed to present a balanced yet complete review of our knowledge, with excursions into the unknown to point out present and future lines of research. The subject of Cosmic Magnetic Fields was split into seven different topics: cosmic magnetic field essentials, solar magnetic fields, stellar magnetic fields, the role of magnetic fields on AGN feedback, magnetic fields in galaxies, magnetic fields in galaxy clusters and at larger scales, and primordial magnetic fields and magnetic fields in the early Universe. The corresponding lectures were delivered by seven well known and experienced scientists that have played key roles in the major advances of the field during the last years: F. Cattaneo, P. Judge, O. Kochukhov, R. Keppens, R. Beck, K. Dolag, and F. Finelli. Their lectures were recorded and are freely available at the IAC website: http://iactalks.iac.es/talks/serie/19.

  1. Quantum field theory

    International Nuclear Information System (INIS)

    Ryder, L.H.

    1985-01-01

    This introduction to the ideas and techniques of quantum field theory presents the material as simply as possible and is designed for graduate research students. After a brief survey of particle physics, the quantum theory of scalar and spinor fields and then of gauge fields, is developed. The emphasis throughout is on functional methods, which have played a large part in modern field theory. The book concludes with a bridge survey of ''topological'' objects in field theory and assumes a knowledge of quantum mechanics and special relativity

  2. Unitary field theories

    International Nuclear Information System (INIS)

    Bergmann, P.G.

    1980-01-01

    A problem of construction of the unitary field theory is discussed. The preconditions of the theory are briefly described. The main attention is paid to the geometrical interpretation of physical fields. The meaning of the conceptions of diversity and exfoliation is elucidated. Two unitary field theories are described: the Weyl conformic geometry and Calitzy five-dimensioned theory. It is proposed to consider supersymmetrical theories as a new approach to the problem of a unitary field theory. It is noted that the supergravitational theories are really unitary theories, since the fields figuring there do not assume invariant expansion

  3. Field emission electronics

    CERN Document Server

    Egorov, Nikolay

    2017-01-01

    This book is dedicated to field emission electronics, a promising field at the interface between “classic” vacuum electronics and nanotechnology. In addition to theoretical models, it includes detailed descriptions of experimental and research techniques and production technologies for different types of field emitters based on various construction principles. It particularly focuses on research into and production of field cathodes and electron guns using recently developed nanomaterials and carbon nanotubes. Further, it discusses the applications of field emission cathodes in new technologies such as light sources, flat screens, microwave and X-ray devices.

  4. Strong Magnetic Field Characterisation

    Science.gov (United States)

    2012-04-01

    an advertised surface field of approximately 0.5 T were used to supply the static magnetic field source. The disc magnet had a diameter of 50 mm and... colour bar indicates the magnetic field strength set to an arbitrary 0.25 T. The white area has a field >0.25 T. The size of the arrow is proportional...9 shows the magnetic field strength along a slice in the XZ plane. The colours represent the total UNCLASSIFIED 10 UNCLASSIFIED DSTO-TR-2699

  5. Monte Carlo method for dose calculation due to oral X-rays; Coeficientes de conversao para calculo de doses devidos a radiografias odontologicas utilizando o metodo de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Eduardo Cesar de Miranda

    1998-06-01

    The increasing utilization of oral X-rays, especially in youngsters and children, calls for the assessment of equivalent doses in their organs and tissues. With this purpose, a Monte Carlo code was adapted to simulate an X-ray source irradiating phantoms of the MIRD-5 type with different ages (10, 15 and 40 years old) to calculate the conversion coefficients which transform the exposure at skin to equivalent doses at several organs and tissues of interest. In order to check the computer program, simulations were performed for adult patients using the original code (ADAM.FOR developed at the GSF-Germany) and the adapted program (MCDRO.PAS). Good agreement between results obtained with both codes was observed. Irradiations of the incisive, canine and molar teeth were simulated. The conversion factors were calculated for the following organs and tissues: thyroid, active bone narrow (head and whole body), bone (facial skeleton, cranium and whole body), skin (head and whole body) and crystalline. Based on the obtained results, it follows that the younger the patient and the larger the field area, the higher the dose in assessed organs and tissues. The variation of the source-skin distance does not change the conversion coefficients. On the other hand, the increase in the voltage applied to the X-ray tube causes an increase in the calculated conversion coefficients. (author)

  6. Two media method for linear attenuation coefficient determination of irregular soil samples; Metodo dos dois meios para a determinacao do coeficiente de atenuacao linear de amostras irregulares de solos

    Energy Technology Data Exchange (ETDEWEB)

    Vici, Carlos Henrique Georges

    2004-07-01

    In several situations of nuclear applications, the knowledge of gamma-ray linear attenuation coefficient for irregular samples is necessary, such as in soil physics and geology. This work presents the validation of a methodology for the determination of the linear attenuation coefficient ({mu}) of irregular shape samples, in such a way that it is not necessary to know the thickness of the considered sample. With this methodology irregular soil samples (undeformed field samples) from Londrina region, north of Parana were studied. It was employed the two media method for the {mu} determination. It consists of the {mu} determination through the measurement of a gamma-ray beam attenuation by the sample sequentially immersed in two different media, with known and appropriately chosen attenuation coefficients. For comparison, the theoretical value of {mu} was calculated by the product of the mass attenuation coefficient, obtained by the WinXcom code, and the measured value of the density sample. This software employs the chemical composition of the samples and supplies a table of the mass attenuation coefficients versus the photon energy. To verify the validity of the two media method, compared with the simple gamma ray transmission method, regular pome stone samples were used. With these results for the attenuation coefficients and their respective deviations, it was possible to compare the two methods. In this way we concluded that the two media method is a good tool for the determination of the linear attenuation coefficient of irregular materials, particularly in the study of soils samples. (author)

  7. Method to Solve the Problem of the Radioactivity Detection in Environmental Samples. Characteristic Limits; Metodos para la Resolucion del Problema de la Detecfcion de Radiactividad en Muestras Ambientales. Limites Caracteristicos

    Energy Technology Data Exchange (ETDEWEB)

    Gasco, C.; Martinez, M.; Heras, M.

    2009-07-21

    The problem of the detection or when the radioactivity can be considered as higher than the background using different measurement techniques has been the objective of several statistical studies and controversies. The detection limit and the critical limit were studied by Currie in year 1968 and used by radiochemistry laboratories considering different ways of calculation that introduced confusion and not correct implementations. In the last few years, and due to the increasing number of standardization processes on the field of radioactivity and accreditation, several international institutions have chosen to unify the criteria for using common determination of detection limits. The most used methods are those developed by MARLAP and International Standard Organization ISO (Standard-11929). In this report are summarised both standards doing a comparative study and giving some examples of how to apply these limits. In same cases, little differences in the uncertainty calculation have been observed but the final results have been concordant. A deeply study of these standards can be done consulting the web page of the American Labs that developed MARLAP or buying the original ISO standard ISO-11929 recently approved (2009). (Author) 17 refs.

  8. Analysis of the extension and reduction method of qualified life used in equipment with ambiental qualification; Analisis del metodo de extension y reduccion de vida calificada utilizado en equipo con calificacion ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Serrano R, M.L. [CNSNS, 03020 Mexico D.F. (Mexico)].e -mail: mlserrano@cnsns.gob.mx

    2005-07-01

    With the purpose of reducing costs of acquisition, maintenance, design, hour-man, dose, production, etc. or by changes in the temperature of service, diverse Nuclear Plants (NP) in the world have been carried out extensions and reductions of life of equipment and/or components related with the safety. The used methods are mainly tests type on equipment or component aged quickly, tests type on equipment or component aged naturally and use of the Arrhenius model with monitoring of temperatures in place. The present article carries out an analysis of the Arrhenius model with monitoring of temperatures in place, which is presented in two variants, equation (1) and (2), since it is the but used by the NP with extension purposes and reduction of qualified life. As back information, it was made one search of investigations, applied to diverse fields of the science that try about the reliability of the results provided by Arrhenius for the aging case. The results of the analysis indicate: I) that this method make uncertainties in some intervals of temperature and 2) which of the two variants it provides data more reliable. (Author)

  9. Recovery of the external anticorrosion protection systems of onshore pipelines - evaluation methods and practical results; Recuperacao de sistemas de protecao anticorrosiva externa de dutos terrestres - metodos de avaliacao e resultados praticos

    Energy Technology Data Exchange (ETDEWEB)

    Castinheiras, Wilson; Koebsch, Andre; Silva, Flavio A. da [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2003-07-01

    The rehabilitation of an old pipeline means to increase its lifetime, making it safety to operate in the necessaries conditions to transport the product. The pipe steel wall evaluation, related to it thickness reduction, due to, basically, internal and external corrosion, is fundamental to guide its rehabilitation. The techniques used to this evaluation are 'pig' and specials field survey. These last surveys are realized over the soil surface (digs is not necessary to access the pipeline or the pipeline operation is not necessary to stop) and objective to verify the pipeline coating and Cathodic Protection System conditions. Due to the actual authors experience, this paper will only treat of the Rehabilitation of the External Anti corrosive Protection System (coating and cathodic protection) of onshore pipelines. This paper present the techniques current attenuation, ON-OFF pipe-to-soil potential close interval survey and DCVG and same practical results obtained with the application of these techniques on the Sergipe/Bahia gas pipeline. (author)

  10. Semi-empirical determination of the diffusion coefficient of the Fricke Xylenol Gel dosimeter through finite difference methods; Determinacao semi-empirica do coeficiente de difusao do dosimetro Fricke Xilenol Gel atraves do metodo de diferencas finitas

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, E.O.; Oliveira, L.N., E-mail: lucas@ifg.edu.br [Instituto Federal de Educacao, Ciencia e Tecnologia de Goias (IFG), Goiania, GO (Brazil)

    2014-11-01

    Partial Differential Equations (PDE) can model natural phenomena, such as related to physics, chemistry and engineering. For these classes of equations, analytical solutions are difficult to be obtained, so a computational approach is indicted. In this context, the Finite Difference Method (FDM) can provide useful tools for the field of Medical Physics. In this study, is described the implementation of a computational mesh, in order to be used in determining the Diffusion Coefficient (DC) of the Fricke Xylenol Gel dosimeter (FXG). The initial and boundary conditions both referred by experimental factors are modelled in FDM, thus making a semi-empirical study in determining the DC. Together, the method of Reflection and Superposition (SRM) and the analysis of experimental data, served as first validation for the simulation. Such methodologies interface generated concordant results for a range of error of 3% in concentration lines for small times when compared to the analytical solution. The result for the DC was 0.43 mm{sup 2} /h. This value is in concordance with measures parameters range found in polymer gels dosimeters: 0.3-2.0 mm{sup 2} /h. Therefore, the application of computer simulation methodology supported by the FDM may be used in determining the diffusion coefficient in FXG dosimeter. (author)

  11. Classical field theory

    CERN Document Server

    Franklin, Joel

    2017-01-01

    Classical field theory, which concerns the generation and interaction of fields, is a logical precursor to quantum field theory, and can be used to describe phenomena such as gravity and electromagnetism. Written for advanced undergraduates, and appropriate for graduate level classes, this book provides a comprehensive introduction to field theories, with a focus on their relativistic structural elements. Such structural notions enable a deeper understanding of Maxwell's equations, which lie at the heart of electromagnetism, and can also be applied to modern variants such as Chern–Simons and Born–Infeld. The structure of field theories and their physical predictions are illustrated with compelling examples, making this book perfect as a text in a dedicated field theory course, for self-study, or as a reference for those interested in classical field theory, advanced electromagnetism, or general relativity. Demonstrating a modern approach to model building, this text is also ideal for students of theoretic...

  12. Earth's electric field

    International Nuclear Information System (INIS)

    Kelley, M.C.

    1978-01-01

    The earth becomes charged during thunderstorm activity and discharges through the weak conducting atmosphere. Balloon and rocket studies infer that a high altitude electric field penetrates virtually unattenuated through the atmosphere, at least as far as balloon heights. The field has two primary sources. At low and mid latitudes, interaction between the earth's magnetic field and the neutral wind creates electric fields. At latitudes above 60 0 , the high altitude electrical structure is dominated by the interaction between the solar wind and the earth's magnetic field. The auroral light is emitted by atmospheric atoms and molecules excited by electrons with potentials of many thousands volts. The potentials are induced by the solar wind. Recent satellite data shows that the electrons get this energy by passing through a localized electric field about 6000 km above the auroral zone. Several rocket and satellite experiments used to study the earth's electric field are discussed

  13. Forces in electromagnetic field and gravitational field

    OpenAIRE

    Weng, Zihua

    2008-01-01

    The force can be defined from the linear momentum in the gravitational field and electromagnetic field. But this definition can not cover the gradient of energy. In the paper, the force will be defined from the energy and torque in a new way, which involves the gravitational force, electromagnetic force, inertial force, gradient of energy, and some other new force terms etc. One of these new force terms can be used to explain why the solar wind varies velocity along the magnetic force line in...

  14. Continuum gauge fields from lattice gauge fields

    International Nuclear Information System (INIS)

    Goeckeler, M.; Kronfeld, A.S.; Schierholz, G.; Wiese, U.J.

    1993-01-01

    On the lattice some of the salient features of pure gauge theories and of gauge theories with fermions in complex representations of the gauge group seem to be lost. These features can be recovered by considering part of the theory in the continuum. The prerequisite for that is the construction of continuum gauge fields from lattice gauge fields. Such a construction, which is gauge covariant and complies with geometrical constructions of the topological charge on the lattice, is given in this paper. The procedure is explicitly carried out in the U(1) theory in two dimensions, where it leads to simple results. (orig.)

  15. Automatic feathering of split fields for step-and-shoot intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    Dogan, Nesrin; Leybovich, Leonid B; Sethi, Anil; Emami, Bahman

    2003-01-01

    Due to leaf travel range limitations of the Varian Dynamic Multileaf Collimator (DMLC) system, an IMRT field width exceeding 14.5 cm is split into two or more adjacent abutting sub-fields. The abutting sub-fields are then delivered as separate treatment fields. The accuracy of the delivery is very sensitive to multileaf positioning accuracy. The uncertainties in leaf and carriage positions cause errors in the delivered dose (e.g., hot or cold spots) along the match line of abutting sub-fields. The dose errors are proportional to the penumbra slope at the edge of each sub-field. To alleviate this problem, we developed techniques that feather the split line of IMRT fields. Feathering of the split line was achieved by dividing IMRT fields into several sub-groups with different split line positions. A Varian 21EX accelerator with an 80-leaf DLMC was used for IMRT delivery. Cylindrical targets with varying widths (>14.5 cm) were created to study the split line positions. Seven coplanar 6 MV fields were selected for planning using the NOMOS-CORVUS TM system. The isocentre of the fields was positioned at the centre of the target volume. Verification was done in a 30 x 30 x 30 cm 3 polystyrene phantom using film dosimetry. We investigated two techniques to move the split line from its original position or cause feathering of them: (1) varying the isocentre position along the target width and (2) introduction of a 'pseudo target' outside of the patient (phantom). The position of the 'pseudo target' was determined by analysing the divergence of IMRT fields. For target widths of 14-28 cm, IMRT fields were automatically split into two sub-fields, and the split line was positioned along the centre of the target by CORVUS. Measured dose distributions demonstrated that the dose to the critical structure was 10% higher than planned when the split line crossed through the centre of the target. Both methods of modifying the split line positions resulted in maximum shifts of ∼1 cm

  16. Polarimetry of random fields

    Science.gov (United States)

    Ellis, Jeremy

    On temporal, spatial and spectral scales which are small enough, all fields are fully polarized. In the optical regime, however, instantaneous fields can rarely be examined, and, instead, only average quantities are accessible. The study of polarimetry is concerned with both the description of electromagnetic fields and the characterization of media a field has interacted with. The polarimetric information is conventionally presented in terms of second order field correlations which are averaged over the ensemble of field realizations. Motivated by the deficiencies of classical polarimetry in dealing with specific practical situations, this dissertation expands the traditional polarimetric approaches to include higher order field correlations and the description of fields fluctuating in three dimensions. In relation to characterization of depolarizing media, a number of fourth-order correlations are introduced in this dissertation. Measurements of full polarization distributions, and the subsequent evaluation of Stokes vector element correlations and Complex Degree of Mutual Polarization demonstrate the use of these quantities for material discrimination and characterization. Recent advancements in detection capabilities allow access to fields near their sources and close to material boundaries, where a unique direction of propagation is not evident. Similarly, there exist classical situations such as overlapping beams, focusing, or diffusive scattering in which there is no unique transverse direction. In this dissertation, the correlation matrix formalism is expanded to describe three dimensional electromagnetic fields, providing a definition for the degree of polarization of such a field. It is also shown that, because of the dimensionality of the problem, a second parameter is necessary to fully describe the polarimetric properties of three dimensional fields. Measurements of second-order correlations of a three dimensional field are demonstrated, allowing the

  17. Optimizing the mercury mass measurement in industrial electrolytic cells by the radio-tracer method at ININ; Optimizacion de la medicion de masa de mercurio en celdas electroliticas industriales por el metodo de radiotrazado en el ININ

    Energy Technology Data Exchange (ETDEWEB)

    Valle R, J.; Angeles C, A., E-mail: Ing.valle.r@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    One method used in the production of chlorine and sodium is the use of electrolytic cells for the separation of chlorine and sodium from the brine; the industries apply very intense electromagnetic fields in this process. The electrolytic cells use mercury as electrode. In a chlorine production plant inventories are determined by total amount of mercury in the plant annually, since mercury losses are large and a very important parameter is to control the mass of mercury for it is necessary to measure with great precision the losses made. There are several methods to determine the mass of mercury ranging from take samples and weigh, but this involves continuous interruption of the process creating downtimes which in turn represent economic losses giving a result delimiting productivity for the industrial sector. An alternative and attractive method is to use a radioactive tracer whose principle has a similar behavior to study objective. The inert mercury has to be neutron activated in a nuclear reactor to having the characteristics of a tracer; the result makes one of the isotopes of mercury. The tracer is transported taking into account the recommendations of the Comision Nacional de Seguridad Nuclear y Salvaguardias (Mexico), then it is injected into the electrolytic cells mixing with the mercury in the system. By a relative radioactivity measurement and one sample by gamma spectrometry per interest cell, the mass of mercury without stopping the process is obtained. For optimal use of radio-tracer method must be taken into account as important features: irradiation time of mercury, counting conditions, vial geometry, sample volume, sample cells, mixing time and half-life of the tracer. (Author)

  18. Covariant electromagnetic field lines

    Science.gov (United States)

    Hadad, Y.; Cohen, E.; Kaminer, I.; Elitzur, A. C.

    2017-08-01

    Faraday introduced electric field lines as a powerful tool for understanding the electric force, and these field lines are still used today in classrooms and textbooks teaching the basics of electromagnetism within the electrostatic limit. However, despite attempts at generalizing this concept beyond the electrostatic limit, such a fully relativistic field line theory still appears to be missing. In this work, we propose such a theory and define covariant electromagnetic field lines that naturally extend electric field lines to relativistic systems and general electromagnetic fields. We derive a closed-form formula for the field lines curvature in the vicinity of a charge, and show that it is related to the world line of the charge. This demonstrates how the kinematics of a charge can be derived from the geometry of the electromagnetic field lines. Such a theory may also provide new tools in modeling and analyzing electromagnetic phenomena, and may entail new insights regarding long-standing problems such as radiation-reaction and self-force. In particular, the electromagnetic field lines curvature has the attractive property of being non-singular everywhere, thus eliminating all self-field singularities without using renormalization techniques.

  19. Partial Komori fields and imperative Komori fields

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2009-01-01

    This paper is concerned with the status of 1/0 and ways to deal with it. These matters are treated in the setting of Komori fields, also known as non-trivial cancellation meadows. Different viewpoints on the status of 1/0 exist in mathematics and theoretical computer science. We give a simple

  20. Nonlocal continuum field theories

    CERN Document Server

    2002-01-01

    Nonlocal continuum field theories are concerned with material bodies whose behavior at any interior point depends on the state of all other points in the body -- rather than only on an effective field resulting from these points -- in addition to its own state and the state of some calculable external field. Nonlocal field theory extends classical field theory by describing the responses of points within the medium by functionals rather than functions (the "constitutive relations" of classical field theory). Such considerations are already well known in solid-state physics, where the nonlocal interactions between the atoms are prevalent in determining the properties of the material. The tools developed for crystalline materials, however, do not lend themselves to analyzing amorphous materials, or materials in which imperfections are a major part of the structure. Nonlocal continuum theories, by contrast, can describe these materials faithfully at scales down to the lattice parameter. This book presents a unif...

  1. Simulated workplace neutron fields

    International Nuclear Information System (INIS)

    Lacoste, V.; Taylor, G.; Rottger, S.

    2011-01-01

    The use of simulated workplace neutron fields, which aim at replicating radiation fields at practical workplaces, is an alternative solution for the calibration of neutron dosemeters. They offer more appropriate calibration coefficients when the mean fluence-to-dose equivalent conversion coefficients of the simulated and practical fields are comparable. Intensive Monte Carlo modelling work has become quite indispensable for the design and/or the characterization of the produced mixed neutron/photon fields, and the use of Bonner sphere systems and proton recoil spectrometers is also mandatory for a reliable experimental determination of the neutron fluence energy distribution over the whole energy range. The establishment of a calibration capability with a simulated workplace neutron field is not an easy task; to date only few facilities are available as standard calibration fields. (authors)

  2. Nonequilibrium quantum field theories

    International Nuclear Information System (INIS)

    Niemi, A.J.

    1988-01-01

    Combining the Feynman-Vernon influence functional formalism with the real-time formulation of finite-temperature quantum field theories we present a general approach to relativistic quantum field theories out of thermal equilibrium. We clarify the physical meaning of the additional fields encountered in the real-time formulation of quantum statistics and outline diagrammatic rules for perturbative nonequilibrium computations. We derive a generalization of Boltzmann's equation which gives a complete characterization of relativistic nonequilibrium phenomena. (orig.)

  3. Organic magnetic field sensor

    Energy Technology Data Exchange (ETDEWEB)

    McCamey, Dane; Boehme, Christoph

    2017-01-24

    An organic, spin-dependent magnetic field sensor (10) includes an active stack (12) having an organic material with a spin-dependence. The sensor (10) also includes a back electrical contact (14) electrically coupled to a back of the active stack (12) and a front electrical contact (16) electrically coupled to a front of the active stack (12). A magnetic field generator (18) is oriented so as to provide an oscillating magnetic field which penetrates the active stack (12).

  4. Elementary quantum field theory

    International Nuclear Information System (INIS)

    Thirring, W.; Henley, E.M.

    1975-01-01

    The first section of the book deals with the mathematical and physical description of a quantum field with the Bose-Einstein statistics and discusses observables, invariants of the field, and inner symmetries. The second section develops further methods for solvable interactions of a quantum field with static source. Section 3 explains with the aid of the Chew-Low model especially pion-nucleon scattering, static properties of nucleons, electromagnetic phenomena, and nuclear forces. (BJ/LN) [de

  5. Wake field accelerators

    International Nuclear Information System (INIS)

    Wilson, P.B.

    1986-02-01

    In a wake field accelerator a high current driving bunch injected into a structure or plasma produces intense induced fields, which are in turn used to accelerate a trailing charge or bunch. The basic concepts of wake field acceleration are described. Wake potentials for closed cavities and periodic structures are derived, as are wake potentials on a collinear path with a charge distribution. Cylindrically symmetric structures excited by a beam in the form of a ring are considered

  6. Geomagnetic field, global pattern

    OpenAIRE

    Macmillan, Susan

    2011-01-01

    The geomagnetic field is generated in the fluid outer core region of the Earth by electrical currents flowing in the slowly moving molten iron. In addition to sources in the Earth’s core, the geomagnetic field observable on the Earth’s surface has sources in the crust and in the ionosphere and magnetosphere. The signal from the core dominates, accounting for over 95% of the field at the Earth’s surface. The geomagnetic field varies on a range of scales, both temporal and spatial; the...

  7. Effective quantum field theories

    International Nuclear Information System (INIS)

    Georgi, H.M.

    1993-01-01

    The most appropriate description of particle interactions in the language of quantum field theory depends on the energy at which the interactions are studied; the description is in terms of an ''effective field theory'' that contains explicit reference only to those particles that are actually important at the energy being studied. The various themes of the article are: local quantum field theory, quantum electrodynamics, new physics, dimensional parameters and renormalizability, socio-dynamics of particle theory, spontaneously broken gauge theories, scale dependence, grand unified and effective field theories. 2 figs

  8. Closed string field theory

    International Nuclear Information System (INIS)

    Strominger, A.

    1987-01-01

    A gauge invariant cubic action describing bosonic closed string field theory is constructed. The gauge symmetries include local spacetime diffeomorphisms. The conventional closed string spectrum and trilinear couplings are reproduced after spontaneous symmetry breaking. The action S is constructed from the usual ''open string'' field of ghost number minus one half. It is given by the associator of the string field product which is non-vanishing because of associativity anomalies. S does not describe open string propagation because open string states associate and can thereby be shifted away. A field theory of closed and open strings can be obtained by adding to S the cubic open string action. (orig.)

  9. Dielectrics in electric fields

    CERN Document Server

    Raju, Gorur G

    2003-01-01

    Discover nontraditional applications of dielectric studies in this exceptionally crafted field reference or text for seniors and graduate students in power engineering tracks. This text contains more than 800 display equations and discusses polarization phenomena in dielectrics, the complex dielectric constant in an alternating electric field, dielectric relaxation and interfacial polarization, the measurement of absorption and desorption currents in time domains, and high field conduction phenomena. Dielectrics in Electric Fields is an interdisciplinary reference and text for professionals and students in electrical and electronics, chemical, biochemical, and environmental engineering; physical, surface, and colloid chemistry; materials science; and chemical physics.

  10. Geomagnetic field of earth

    International Nuclear Information System (INIS)

    Delipetrev, Marjan; Delipetrev, Blagoj; Panovska, Sanja

    2008-01-01

    In this paper is introduced the theory of geomagnetic field of the Earth. A homogenous and isotropic sphere is taken for a model of Earth with a bar magnet at its center as a magnetic potential. The understanding of the real origin of geomagnetic field produced from differential rotation of inner core with respect to the outer core of Earth is here presented. Special attention is given to the latest observed data of the established net of geomagnetic repeat stations in the Republic of Macedonia. Finally, the maps of elements of geomagnetic field and the equation for calculation of normal magnetic field of Earth are provided. (Author)

  11. Fields, symmetries, and quarks

    International Nuclear Information System (INIS)

    Mosel, U.

    1989-01-01

    'Fields, symmetries, and quarks' covers elements of quantum field theory, symmetries, gauge field theories and phenomenological descriptions of hadrons, with special emphasis on topics relevant to nuclear physics. It is aimed at nuclear physicists in general and at scientists who need a working knowledge of field theory, symmetry principles of elementary particles and their interactions and the quark structure of hadrons. The book starts out with an elementary introduction into classical field theory and its quantization. As gauge field theories require a working knowledge of global symmetries in field theories this topic is then discussed in detail. The following part is concerned with the general structure of gauge field theories and contains a thorough discussion of the still less widely known features of Non-Abelian gauge field theories. Quantum Chromodynamics (QCD), which is important for the understanding of hadronic matter, is discussed in the next section together with the quark compositions of hadrons. The last two chapters give a detailed discussion of phenomenological bag-models. The MIT bag is discussed, so that all theoretical calculations can be followed step by step. Since in all other bag-models the calculational methods and steps are essentially identical, this chapter should enable the reader to actually perform such calculations unaided. A last chapter finally discusses the topological bag-models which have become quite popular over the last few years. (orig.)

  12. The Control of Fast Reactors: Current Methods and Future Prospects; Controle des Reacteurs a Neutrons Rapides. Methodes Actuelles et Perspectives d'Avenir; Upravlenie reaktorami na bystrykh nejtronakh. sushchestvuyushchie metody i dal'nejshie perspektivy; Control de Reactores Rapidos: Metodos Actuales y Perspectivas

    Energy Technology Data Exchange (ETDEWEB)

    Loewenstein, W. B. [Argonne National Laboratory, IL (United States)

    1964-06-15

    examina los actuales mecanismos de control de los reactores de neutrones rapidos. En la medida de lo posible aprovechan el control por medio de fugas neutronicas. Si este metodo no es aplicable se suele recurrir al control por desplazamiento de los materiales del cuerpo. Igualmente se recurre a un control limitado utilizando un absorbente. Ninguno de estos metodos presenta ventajas considerables cuando se aplica a los'grandes reactores de potencia regeneradores, a menos que la razon interna de regeneracion (del cuerpo) sea muy elevada. Se requerira mucha habilidad para utilizar metodos de control basados en el empleo de un absorbente o en el desplazamiento espectral sin afectar en grado apreciable la economia neutronica deseada y a menudo necesaria. El autor cita algunos resultados preliminares obtenidos con sistemas perfeccionados. La reactividad de control viene determinada por los requisitos relativos a la parada del reactor, al ciclo del combustible (exceso de reactividad) y, en menor medida, por la realimentacion dominante. Pueden especificarse perfectamente los requisitos relativos al exceso de reactividad para un ciclo de combustible determinado, pero esos requisitos varian de modo considerable en otros sistemas similares que funcionen con distintos ciclos de combustible. A partir de ciertos limites, pueden fijarse casi arbitrariamente les requisitos relativos al exceso de reactividad. Sin embargo, existen algunas consideraciones generales que rigen la determinacion de este parametro. Se tienen en cuenta dichas consideraciones al examinar la reactividad de control en los actuales reactores de neutrones rapidos comparandola a la cantidad realmente necesaria para el funcionamiento de reactores de potencia regeneradores y neutrones rapidos. El autor cita parametros tipicos de potencia y de realimentacion en funcion de la temperatura a fin de determinar su influencia en los requisitos relativos a la reactividad de control. Los metodos utilizados para predecir la

  13. Electrochemical performance in the hydrogen evolution reaction of Ni-TR (TR= La, Ce) materials synthesized using the solid state reaction method; Desempeno electroquimico en la reaccion de evolucion de hidrogeno de materiales de electrodo Ni-TR (TR = La, Ce) sintetizados por el metodo de reaccion de estado solido

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Huerta, A. M.; Dominguez-Crespo, M. A.; Ramirez-Meneses, E.; Yanez-Zamora, C. [CICATA, IPN, Altamira, Tamaulipas (Mexico); Avila-Garcia, I. [IPN, ESIQIE, UPALM, Mexico, D.F. (Mexico)]. E-mail: mdominguezc@ipn.mx; adcrespo2000@yahoo.com.mx

    2009-09-15

    relacionados con su operacion. El material de electrodo con mayor electroactividad es el Pt, pero debido a su costo elevado se han tenido que buscar electrocatalizadores alternativos con un balance entre costo y actividad. Uno de los materiales que mas se ha utilizado es el Niquel en conjunto con algunas de sus aleaciones. Este material ha demostrado un buen desempeno utilizando bajos sobrepotenciales en reacciones tradicionales como las reacciones de evolucion de hidrogeno (REH) y oxigeno (REO), asi como una alta resistencia a la corrosion y bajo costo. Particularmente, aleaciones binarias y ternarias han demostrado un incremento importante en la actividad de la REH al compararla con los materiales en su estado puro o masivo. Por esta razon, en la busqueda de nuevas alternativas con una aceptable eficiencia al compararla con los materiales a bajo costo, en este trabajo se obtuvieron materiales Ni-TR (TR = La, Ce) por el metodo de reaccion de estado solido, a partir de: a) acetilacetonatos metalicos y b) polvos metalicos. Estos materiales se sinterizaron durante 3 h a diferentes temperaturas (795 o 920 , 1000 y 1200 grados centigrados) a fin de evaluar su efecto en el desempeno electroquimico de los electrocatalizadores. La caracterizacion estructural y morfologica de materiales se realizo por las tecnicas de DRX y MEB, respectivamente. Asimismo, el desempeno electroquimico de los materiales de electrodo se evaluo en la REH utilizando voltametria ciclica (VC) y curvas potenciodinamicas. Los resultados obtenidos muestran que a bajas temperaturas se obtiene una mezcla de oxidos (NiO, CeO{sub 2} y LaNiO{sub 3}); sin embargo a medida que la temperatura de sinterizado se incrementa, se alcanza la formacion de las aleaciones NiO-CeO{sub 2} y NiO-LaNiO{sub 3}, respectivamente. Al mismo tiempo se observo una clara dependencia de la actividad electrocatalitica con la fuente obtencion de estos materiales (Ni-TR).

  14. Avaliação da composição corporal em adolescentes obesos: o uso de dois diferentes métodos Evaluación de la composición corporal en adolescentes obesos: uso de dos metodos diferentes Body composition evaluation in obese adolescents: the use of two different methods

    Directory of Open Access Journals (Sweden)

    Marco Túlio de Mello

    2005-10-01

    Full Text Available A pletismografia é um método rápido e fácil para determinação da composição corporal que utiliza a relação inversa entre pressão e volume. O objetivo do presente estudo foi o de comparar os valores obtidos com o método pletismografia com os valores observados com o DEXA em uma população de adolescentes obesos. Participaram da amostra 88 adolescentes pós-púberes de ambos os sexos, com idades entre 15 e 19 anos (17,01 ± 1,6 ingressantes de um programa de atividade física multidisciplinar. Os voluntários foram submetidos a uma avaliação da composição corporal em dias distintos dentro da mesma semana, pelo método de pletismografia e outra avaliação pelo método DEXA. Quando os métodos foram comparados, não se observaram diferenças significativas entre eles; além disso, foram observadas correlações significativas entre os parâmetros comuns dos dois métodos (massa magra, massa gorda (kg e massa gorda (%, r = 0,88 p La pletismografía es un método rápido y fácil para la determinación de la composición corporal que utiliza la relación inversa entre la presión y el volumen. El objetivo del presente estudio fué el de comparar los valores obtenidos con el metodo pletismografia con los valores observados con el DEXA en una población de adolescentes obesos. Participaron de la muestra 80 adolescentes post púberes de ambos sexos, con edades entre los 15 y los 19 años (17,01±1,6 iniciantes en un programa de actividad física multidisciplinar. Los voluntarios fueron sometidos a una evaluación de la composición corporal en días distintos dentro de la misma semana, por el método de pletismografia y otra evaluación por el método DEXA. Cuando se compararon los métodos, no fueron observadas diferencias significativas entre ellos, además de ello, fueron observadas correlaciones entre los parámetros comunes a los dos métodos (masa magra, masa grasa (kg y masa gorda (%, r = 0,88 p Plethysmography is an easy and

  15. Effective field theories

    International Nuclear Information System (INIS)

    Mack, G.; Kalkreuter, T.; Palma, G.; Speh, M.

    1992-05-01

    Effective field theories encode the predictions of a quantum field theory at low energy. The effective theory has a fairly low utraviolet cutoff. As a result, loop corrections are small, at least if the effective action contains a term which is quadratic in the fields, and physical predictions can be read straight from the effective Lagrangean. Methods will be discussed how to compute an effective low energy action from a given fundamental action, either analytically or numerically, or by a combination of both methods. Basically, the idea is to integrate out the high frequency components of fields. This requires the choice of a 'blockspin', i.e. the specification af a low frequency field as a function of the fundamental fields. These blockspins will be fields of the effective field theory. The blockspin need not be a field of the same type as one of the fundamental fields, and it may be composite. Special features of blockspin in nonabelian gauge theories will be discussed in some detail. In analytical work and in multigrid updating schemes one needs interpolation kernels A from coarse to fine grid in addition to the averaging kernels C which determines the blockspin. A neural net strategy for finding optimal kernels is presented. Numerical methods are applicable to obtain actions of effective theories on lattices of finite volume. The special case of a 'lattice' with a single site (the constraint effective potential) is of particular interest. In a higgs model, the effective action reduces in this case to the free energy, considered as a function of a gauge covariant magnetization. Its shape determines the phase structure of the theory. Its loop expansion with and without gauge fields can be used to determine finite size corrections to numerical data. (orig.)

  16. Diffusion Parameters of BeO by the Pulsed Neutron Method; Calcul des Parametres de Diffusion de BeO par la Methode des Neutrons Pulses; Opredelenie diffuzionnykh parametrov BeO s pomoshch'yu metoda impul'snykh nejtronov; Determinacion de los Parametros de Difusion en el BeO por el Metodo de los Neutrones Pulsados

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, B. V.; Nargundkar, V. R.; Subbarao, K. [Atomic Energy Establishment Trombay, Bombay (India)

    1965-08-15

    la position et la longueur du compteur d'une part, la position de la source d'autre part, il est possible d'eliminer la plupart des harmoniques spatiaux. Il est egalement possible de tenir compte de n'importe quel bruit de fond constant pour le calcul de la constante de decroissance. Il faut eviter les laplaciens tres eleves afin de ne pas avoir d {sup h}armoniques du temps. Tous les harmoniques qui restent sont rendus inoperants par un retard en temps adequat. Les auteurs ont determine la constante de decroissance du mode fondamental de la population de neutrons thermiques pour plusieurs laplaciens. Ils discutent les conditions a remplir pour une determination exacte de la constante du refroidissement par diffusion C. Pour la glucine, ils ont obtenu les constantes suivantes: {lambda}{sub 0} (constante d'absorption) = 156, 02 {+-} 4, 37 s{sup -1}. D (coefficient dediffusion) = (1,3334 {+-} 0,0128) * 10{sup 5} cm{sup 2}/s, C (constante du refroidissement de diffusion) = (-4,8758 {+-} 0,5846) * 10{sup 5} cm{sup 4}/s. Les auteurs ont etudie le role que peut jouer, dans la determination des parametres de diffusion, le fait que la contribution du terme en B{sup 6} est neglige; ils montrent qu'il est considerable. Ce serait la probablement la cause des ecarts entre les valeurs de C obtenues pour un meme ralentisseur par differents chercheurs. (author) [Spanish] Los autores describen el empleo del metodo de los neutrones pulsados para determinar con precision los parametros de difusion en moderadores. Con ayuda de este metodo, han obtenido los parametros de difusion en el BeO. Las rafagas de neutrones se generaron mediante un acelerador en cascada pulsando la fuente ionica y empleando la reaccion Be (d, n). Como detector se utilizo un contador proporcional de BF{sub 3} enriquecido. Los autores demuestran que por seleccion adecuada de la posicion y longitud del contador y de la ubicacion de la fuente, pueden eliminarse la mayoria de los armonicos espaciales. En el calculo de

  17. twistors and gauge fields

    Directory of Open Access Journals (Sweden)

    A. G. Sergeev

    1986-01-01

    Full Text Available We describe briefly the basic ideas and results of the twistor theory. The main points: twistor representation of Minkowsky space, Penrose correspondence and its geometrical properties, twistor interpretation of linear massless fields, Yang-Mills fields (including instantons and monopoles and Einstein-Hilbert equations.

  18. Hyperfunction quantum field theory

    International Nuclear Information System (INIS)

    Nagamachi, S.; Mugibayashi, N.

    1976-01-01

    The quantum field theory in terms of Fourier hyperfunctions is constructed. The test function space for hyperfunctions does not contain C infinitely functios with compact support. In spite of this defect the support concept of H-valued Fourier hyperfunctions allows to formulate the locality axiom for hyperfunction quantum field theory. (orig.) [de

  19. Mean field games

    KAUST Repository

    Gomes, Diogo A.

    2014-01-06

    In this talk we will report on new results concerning the existence of smooth solutions for time dependent mean-field games. This new result is established through a combination of various tools including several a-priori estimates for time-dependent mean-field games combined with new techniques for the regularity of Hamilton-Jacobi equations.

  20. Quantum field theory

    CERN Document Server

    Sadovskii, Michael V

    2013-01-01

    This book discusses the main concepts of the Standard Model of elementary particles in a compact and straightforward way. The work illustrates the unity of modern theoretical physics by combining approaches and concepts of the quantum field theory and modern condensed matter theory. The inductive approach allows a deep understanding of ideas and methods used for solving problems in this field.

  1. Killing fields; The politics

    Energy Technology Data Exchange (ETDEWEB)

    Philips, Alasdair

    1990-02-01

    An overview considers the NRPB guidelines on possible health effects of low-level alternating electrical and magnetic fields and examines work by individuals on the hazards of microwave radiation, overhead power lines and childhood cancer, and the problems caused by electromagnetic fields at 50 Hz frequency. (U.K.).

  2. Moving Field Guides

    Science.gov (United States)

    Cassie Meador; Mark Twery; Meagan. Leatherbury

    2011-01-01

    The Moving Field Guides (MFG) project is a creative take on site interpretation. Moving Field Guides provide an example of how scientific and artistic endeavors work in parallel. Both begin with keen observations that produce information that must be analyzed, understood, and interpreted. That interpretation then needs to be communicated to others to complete the...

  3. Respirator field performance factors

    International Nuclear Information System (INIS)

    Skaggs, B.J.; DeField, J.D.; Strandberg, S.W.; Sutcliffe, C.R.

    1985-01-01

    The Industrial Hygiene Group assisted OSHA and the NRC in measurements of respirator performance under field conditions. They reviewed problems associated with sampling aerosols within the respirator in order to determine fit factors (FFs) or field performance factor (FPF). In addition, they designed an environmental chamber study to determine the effects of temperature and humidity on a respirator wearer

  4. Magnetic field on board

    International Nuclear Information System (INIS)

    Estevez Radio, H.; Fernandez Arenal, C.A.

    1995-01-01

    Here, the calculation of the magnetic field on board ships is performed, using matrix calculus, in a similar way as when the magnetic field in matter is studied. Thus the final formulas are written in a more compact form and they are obtained through a simpler way, more suitable for the university education. (Author)

  5. Pregnancy and electromagnetic fields

    International Nuclear Information System (INIS)

    Bisseriex, Ch.; Laurent, P.; Cabaret, Ph.; Bonnet, C.; Marteau, E.; Le Berre, G.; Tirlemont, S.; Castro, H.; Becker, A.; Demaret, Ph.; Donati, M.; Ganem, Y.; Moureaux, P.

    2011-07-01

    This document briefly indicates the status of knowledge regarding the effect of magnetic fields on biological tissues and pregnancy, outlines the lack of data on some frequencies and the weakness of studies on long term effects on child development. It evokes the issue of exposure assessment and that of identification of workstations exposed to electromagnetic fields

  6. Magnetic field line Hamiltonian

    International Nuclear Information System (INIS)

    Boozer, A.H.

    1984-03-01

    The magnetic field line Hamiltonian and the associated canonical form for the magnetic field are important concepts both for understanding toroidal plasma physics and for practical calculations. A number of important properties of the canonical or Hamiltonian representation are derived and their importance is explained

  7. Fields From Markov Chains

    DEFF Research Database (Denmark)

    Justesen, Jørn

    2005-01-01

    A simple construction of two-dimensional (2-D) fields is presented. Rows and columns are outcomes of the same Markov chain. The entropy can be calculated explicitly.......A simple construction of two-dimensional (2-D) fields is presented. Rows and columns are outcomes of the same Markov chain. The entropy can be calculated explicitly....

  8. Pulsed electric fields

    Science.gov (United States)

    The concept of pulsed electric fields (PEF) was first proposed in 1967 to change the behavior or microorganisms. The electric field phenomenon was identified as membrane rupture theory in the 1980s. Increasing the membrane permeability led to the application of PEF assisted extraction of cellular co...

  9. MAGNETIC FIELDS OF STARS

    OpenAIRE

    Bychkov, V. D.; Bychkova, L. V.; Madej, J.

    2008-01-01

    Now it is known about 1212 stars of the main sequence and giants (from them 610 stars - it is chemically peculiarity (CP) stars) for which direct measurements of magnetic fields were spent (Bychkov et al.,2008). Let's consider, what representations were generated about magnetic fields (MT) of stars on the basis of available observations data.

  10. Quantization and nonlocal fields

    International Nuclear Information System (INIS)

    Kolerov, G.I.

    1977-01-01

    A relation between the postulate of causality and quatization conditions is considered for the scalar field. A formalism of outer forms given on the functional space is used. A current commutator is obtained for nonlogical fields in the space-like region

  11. Mean field games

    KAUST Repository

    Gomes, Diogo A.

    2014-01-01

    In this talk we will report on new results concerning the existence of smooth solutions for time dependent mean-field games. This new result is established through a combination of various tools including several a-priori estimates for time-dependent mean-field games combined with new techniques for the regularity of Hamilton-Jacobi equations.

  12. Unified field theory

    International Nuclear Information System (INIS)

    Vollendorf, F.

    1976-01-01

    A theory is developed in which the gravitational as well as the electromagnetic field is described in a purely geometrical manner. In the case of a static central symmetric field Newton's law of gravitation and Schwarzschild's line element are derived by means of an action principle. The same principle leads to Fermat's law which defines the world lines of photons. (orig.) [de

  13. Pregnant Field Students' Guilt

    Science.gov (United States)

    Baum, Nehami

    2006-01-01

    This study examined guilt feelings among social work students who were pregnant for the first time during field work training. Semi-structured interviews were conducted either in the 9th month (n=5) or 2-12 months after delivery (n=5). Content analysis revealed 6 main triggers, illustrated by excerpts, which stimulated field students' guilt…

  14. Electromagnetic fields in biological systems

    National Research Council Canada - National Science Library

    Lin, James C

    2012-01-01

    "Focusing on exposure, induced fields, and absorbed energy, this volume covers the interaction of electromagnetic fields and waves with biological systems, spanning static fields to terahertz waves...

  15. The Coriolis field

    Science.gov (United States)

    Costa, L. Filipe; Natário, José

    2016-05-01

    We present a pedagogical discussion of the Coriolis field, emphasizing its not-so-well-understood aspects. We show that this field satisfies the field equations of the so-called Newton-Cartan theory, a generalization of Newtonian gravity that is covariant under changes of arbitrarily rotating and accelerated frames. Examples of solutions of this theory are given, including the Newtonian analogue of the Gödel universe. We discuss how to detect the Coriolis field by its effect on gyroscopes, of which the gyrocompass is an example. Finally, using a similar framework, we discuss the Coriolis field generated by mass currents in general relativity, and its measurement by the gravity probe B and LAGEOS/LARES experiments.

  16. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

  17. Finite fields and applications

    CERN Document Server

    Mullen, Gary L

    2007-01-01

    This book provides a brief and accessible introduction to the theory of finite fields and to some of their many fascinating and practical applications. The first chapter is devoted to the theory of finite fields. After covering their construction and elementary properties, the authors discuss the trace and norm functions, bases for finite fields, and properties of polynomials over finite fields. Each of the remaining chapters details applications. Chapter 2 deals with combinatorial topics such as the construction of sets of orthogonal latin squares, affine and projective planes, block designs, and Hadamard matrices. Chapters 3 and 4 provide a number of constructions and basic properties of error-correcting codes and cryptographic systems using finite fields. Each chapter includes a set of exercises of varying levels of difficulty which help to further explain and motivate the material. Appendix A provides a brief review of the basic number theory and abstract algebra used in the text, as well as exercises rel...

  18. Dual double field theory

    Energy Technology Data Exchange (ETDEWEB)

    Bergshoeff, Eric A. [Centre for Theoretical Physics, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands); Hohm, Olaf [Simons Center for Geometry and Physics, Stony Brook University,Stony Brook, NY 11794-3636 (United States); Penas, Victor A. [Centre for Theoretical Physics, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands); Riccioni, Fabio [INFN - Sezione di Roma, Dipartimento di Fisica, Università di Roma “La Sapienza”,Piazzale Aldo Moro 2, 00185 Roma (Italy)

    2016-06-06

    We present the dual formulation of double field theory at the linearized level. This is a classically equivalent theory describing the duals of the dilaton, the Kalb-Ramond field and the graviton in a T-duality or O(D,D) covariant way. In agreement with previous proposals, the resulting theory encodes fields in mixed Young-tableau representations, combining them into an antisymmetric 4-tensor under O(D,D). In contrast to previous proposals, the theory also requires an antisymmetric 2-tensor and a singlet, which are not all pure gauge. The need for these additional fields is analogous to a similar phenomenon for “exotic' dualizations, and we clarify this by comparing with the dualizations of the component fields. We close with some speculative remarks on the significance of these observations for the full non-linear theory yet to be constructed.

  19. Field theory and strings

    International Nuclear Information System (INIS)

    Bonara, L.; Cotta-Ramusino, P.; Rinaldi, M.

    1987-01-01

    It is well-known that type I and heterotic superstring theories have a zero mass spectrum which correspond to the field content of N=1 supergravity theory coupled to supersymmetric Yang-Mills theory in 10-D. The authors study the field theory ''per se'', in the hope that simple consistency requirements will determine the theory completely once one knows the field content inherited from string theory. The simplest consistency requirements are: N=1 supersymmetry; and absence of chiral anomalies. This is what the authors discuss in this paper here leaving undetermined the question of the range of validity of the resulting field theory. As is known, a model of N=1 supergravity (SUGRA) coupled to supersymmetric Yang-Mills (SYM) theory was known in the form given by Chapline and Manton. The coupling of SUGRA to SYM was determined by the definition of the ''field strength'' 3-form H in this paper

  20. Narrowing the field

    DEFF Research Database (Denmark)

    Knudsen, Bo Nissen

    characteristics and the sequence of information in the series. Adding to the challenge is the macrostructural variation: The areas covered in printed form are covered with shifting principles of selecting the names to be published. Finding the right balance between letting the algorithms structure this complex....... As of now, no less than 45 different database fields have been found necessary to structure the information found in a single place-name entry – some fields mandatory, some nonmandatory. And using a relational database structure, some fields have multiple occurrences within one entry (i.e. multiple source...... forms for one entry a.s.f.). Having made the conscious decision to split up the information into so many categories (i.e. fields) – instead of employing a broad 'other information' field – sophisticated algorithms have been developed in order to identify information category from typographical...

  1. Magnetic fields in cosmology

    International Nuclear Information System (INIS)

    Madsen, M.S.

    1989-01-01

    The possible role of a large-scale relic magnetic field in the history of the Universe is considered. The perturbation of the cosmic microwave back-ground radiation on large angular scales due to a homogeneous magnetic field is estimated in a simple relativistic model. This allows corresponding limits to be placed on the magnitude of any such large-scale relic magnetic field at the present time. These limits are essentially the strongest which can be set on the largest scales. A corresponding bound is obtained by use of the requirement that the field should not spoil the predictions of primordial nucleosynthesis. It is noted that the existence of large-scale cosmic magnetic fields would circumvent the limits previously set - also on the basis of nucleosynthesis considerations - on the large-scale anisotropy now present in the Universe. (author)

  2. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields.......The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...

  3. Non-Destructive Testing Methods Applied to Multi-Finned SAP Tubing for Nuclear-Fuel Elements; Essais Non Destructifs de Gaines a Ailettes, en Poudre d'Aluminium Frittee, pour Elements Combustibles; Nedestruktivnye metody ispytaniya rebristykh trub iz spechennogo alyuminikiog'o poroshka dlya yadernykh toplivnykh ehlementov; Metodos de Ensayo No Destructivo Aplicados a Tubos de SAP con Aletas Multiples Destinados a Elementos Combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Lund, S. A. [Danish Central Welding Institution, Copenhagen (Denmark); Knudsen, P. [Danish Atomic Energy Commission, Research Establishment, Risoe (Denmark)

    1965-09-15

    Energia Atomica de Dinamarca ha emprendido el estudio de un reactor de potencia con refrigerante organico y moderador de agua pesada. Los correspondientes elementos combustibles consisten en haces de 19 barras formadas por pastillas de dioxido de uranio sinterizado, encerradas en tubos de producto de aluminio sinterizado (SAP), de 2 m de longitud, provistos de aletas helicoidales. Para obtener condiciones optimas de transmision de calor y mantener la integridad del elemento combustible durante el funcionamiento del reactor, es necesario contar con tubos de muy alta calidad. Se citan dos ejemplos que ponen de manifiesto las estrechas tolerancias dimensionales adoptadas. Para asegurar una calidad adecuada de los tubos, se establecio un control de calidad muy estricto, basado en gran medida en la aplicacion de metodos no destructivos. Se describen en esta memoria las tecnicas desarrolladas para medir el espesor de pared y los diametros, y para descubrir defectos. La compleja seccion transversal, con 24 aletas, impide aplicar metodos ultrasonicos o de comentes de Foucault para medir el espesor de la pared. Por consiguiente, se desarrollo un calibre registrador de rayos beta, cuyo funcionamiento se basa en la atenuacion sufrida por la radiacion beta proveniente de una fuente de {sup 90}Sr colocada en el interior del tubo. Para el registro continuo del espesor de la pared del tubo con seccion transversal mas simple, de 12 aletas, se utiliza un metodo ultrasonico de resonancia por inmersion. Los diametros interno y externo (entre puntos de aletas) se registran de manera continua mediante calibres neumaticos rapidos. Las fallas se detectan mediante la tecnica de eco de impulsos ultrasonicos, y examinando los tubos con corrientes de Foucault. El metodo ultrasonico permite descubrir facilmente las fisuras transversales, pero hasta ahora ha sido imposible utilizarlo para la deteccion de defectos longitudinales. Por consiguiente, ademas del ensayo ultrasonico, se aplica el examen con

  4. Gauge fields and inflation

    Science.gov (United States)

    Maleknejad, A.; Sheikh-Jabbari, M. M.; Soda, J.

    2013-07-01

    The isotropy and homogeneity of the cosmic microwave background (CMB) favors “scalar driven” early Universe inflationary models. However, gauge fields and other non-scalar fields are far more common at all energy scales, in particular at high energies seemingly relevant to inflation models. Hence, in this review we consider the role and consequences, theoretical and observational, that gauge fields can have during the inflationary era. Gauge fields may be turned on in the background during inflation, or may become relevant at the level of cosmic perturbations. There have been two main classes of models with gauge fields in the background, models which show violation of the cosmic no-hair theorem and those which lead to isotropic FLRW cosmology, respecting the cosmic no-hair theorem. Models in which gauge fields are only turned on at the cosmic perturbation level, may source primordial magnetic fields. We also review specific observational features of these models on the CMB and/or the primordial cosmic magnetic fields. Our discussions will be mainly focused on the inflation period, with only a brief discussion on the post inflationary (p)reheating era. Large field models: The initial value of the inflaton field is large, generically super-Planckian, and it rolls slowly down toward the potential minimum at smaller φ values. For instance, chaotic inflation is one of the representative models of this class. The typical potential of large-field models has a monomial form as V(φ)=V0φn. A simple analysis using the dynamical equations reveals that for number of e-folds Ne larger than 60, we require super-Planckian initial field values,5φ0>3M. For these models typically ɛ˜η˜Ne-1. Small field models: Inflaton field is initially small and slowly evolves toward the potential minimum at larger φ values. The small field models are characterized by the following potential V(φ)=V0(1-(), which corresponds to a Taylor expansion about the origin, but more realistic

  5. The earth's magnetic field

    International Nuclear Information System (INIS)

    Merrill, R.T.

    1983-01-01

    After a historical introduction in Chapter 1, the more traditional aspects of geomagnetism relating to the present field and historical observations are presented in Chapter 2. The various methods and techniques and theoretical background of palaeomagnetism are given in Chapter 3. Chapters 4, 5 and 6 present the results of palaeomagnetic and archaeomagnetic studies in three topics. Chapter 4 relates to studies of the geomagnetic field roughly back to about 50,000 years ago. Chapter 5 is about reversals of the geomagnetic field and Chapter 6 presents studies of the field for times older than 50,000 years and on the geological time scale of millions or hundreds of millions of years. Chapters 7, 8 and 9 provide insight into dynamo theory. Chapter 7 is essentially a non-mathematical attempt to explain the physical basis of dynamo theories to palaeomagnetists. This is followed in Chapter 8 by a more advanced theoretical treatment. Chapter 9 explains theoretical aspects of secular variation and the origin of reversals of the geomagnetic field. Chapter 10 is our attempt to relate theory to experiment and vice versa. The final two chapters consider the magnetic fields of the moon, sun, planets and meteorites, in an attempt to determine the necessary and sufficient conditions for magnetic field generation in large solar system bodies. (author)

  6. Asymmetric kinetic equilibria: Generalization of the BAS model for rotating magnetic profile and non-zero electric field

    Science.gov (United States)

    Dorville, Nicolas; Belmont, Gérard; Aunai, Nicolas; Dargent, Jérémy; Rezeau, Laurence

    2015-09-01

    Finding kinetic equilibria for non-collisional/collisionless tangential current layers is a key issue as well for their theoretical modeling as for our understanding of the processes that disturb them, such as tearing or Kelvin Helmholtz instabilities. The famous Harris equilibrium [E. Harris, Il Nuovo Cimento Ser. 10 23, 115-121 (1962)] assumes drifting Maxwellian distributions for ions and electrons, with constant temperatures and flow velocities; these assumptions lead to symmetric layers surrounded by vacuum. This strongly particular kind of layer is not suited for the general case: asymmetric boundaries between two media with different plasmas and different magnetic fields. The standard method for constructing more general kinetic equilibria consists in using Jeans theorem, which says that any function depending only on the Hamiltonian constants of motion is a solution to the steady Vlasov equation [P. J. Channell, Phys. Fluids (1958-1988) 19, 1541 (1976); M. Roth et al., Space Sci. Rev. 76, 251-317 (1996); and F. Mottez, Phys. Plasmas 10, 1541-1545 (2003)]. The inverse implication is however not true: when using the motion invariants as variables instead of the velocity components, the general stationary particle distributions keep on depending explicitly of the position, in addition to the implicit dependence introduced by these invariants. The standard approach therefore strongly restricts the class of solutions to the problem and probably does not select the most physically reasonable. The BAS (Belmont-Aunai-Smets) model [G. Belmont et al., Phys. Plasmas 19, 022108 (2012)] used for the first time the concept of particle accessibility to find new solutions: considering the case of a coplanar-antiparallel magnetic field configuration without electric field, asymmetric solutions could be found while the standard method can only lead to symmetric ones. These solutions were validated in a hybrid simulation [N. Aunai et al., Phys. Plasmas (1994-present) 20

  7. Asymmetric kinetic equilibria: Generalization of the BAS model for rotating magnetic profile and non-zero electric field

    International Nuclear Information System (INIS)

    Dorville, Nicolas; Belmont, Gérard; Aunai, Nicolas; Dargent, Jérémy; Rezeau, Laurence

    2015-01-01

    Finding kinetic equilibria for non-collisional/collisionless tangential current layers is a key issue as well for their theoretical modeling as for our understanding of the processes that disturb them, such as tearing or Kelvin Helmholtz instabilities. The famous Harris equilibrium [E. Harris, Il Nuovo Cimento Ser. 10 23, 115–121 (1962)] assumes drifting Maxwellian distributions for ions and electrons, with constant temperatures and flow velocities; these assumptions lead to symmetric layers surrounded by vacuum. This strongly particular kind of layer is not suited for the general case: asymmetric boundaries between two media with different plasmas and different magnetic fields. The standard method for constructing more general kinetic equilibria consists in using Jeans theorem, which says that any function depending only on the Hamiltonian constants of motion is a solution to the steady Vlasov equation [P. J. Channell, Phys. Fluids (1958–1988) 19, 1541 (1976); M. Roth et al., Space Sci. Rev. 76, 251–317 (1996); and F. Mottez, Phys. Plasmas 10, 1541–1545 (2003)]. The inverse implication is however not true: when using the motion invariants as variables instead of the velocity components, the general stationary particle distributions keep on depending explicitly of the position, in addition to the implicit dependence introduced by these invariants. The standard approach therefore strongly restricts the class of solutions to the problem and probably does not select the most physically reasonable. The BAS (Belmont-Aunai-Smets) model [G. Belmont et al., Phys. Plasmas 19, 022108 (2012)] used for the first time the concept of particle accessibility to find new solutions: considering the case of a coplanar-antiparallel magnetic field configuration without electric field, asymmetric solutions could be found while the standard method can only lead to symmetric ones. These solutions were validated in a hybrid simulation [N. Aunai et al., Phys. Plasmas (1994-present

  8. The Juno Magnetic Field Investigation

    DEFF Research Database (Denmark)

    Connerney, J. E. P.; Benn, Mathias; Bjarnø, Jonas Bækby

    2017-01-01

    The Juno Magnetic Field investigation (MAG) characterizes Jupiter’s planetary magnetic field and magnetosphere, providing the first globally distributed and proximate measurements of the magnetic field of Jupiter. The magnetic field instrumentation consists of two independent magnetometer sensor ...

  9. Irreversible magnetic-field dependence of ferromagnetic resonance and inverse spin Hall effect voltage in CoFeB/Pt bilayer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang-Il [Department of Materials Science and Engineering, Korea University, Seoul, 136-713 (Korea, Republic of); Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of); Seo, Min-Su [Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of); Choi, Yeon Suk, E-mail: ychoi@kbsi.re.kr [Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of); Park, Seung-Young, E-mail: parksy@kbsi.re.kr [Spin Engineering Physics Team, Division of Scientific Instrumentation, Korea Basic Science Institute, Daejeon, 305-806 (Korea, Republic of)

    2017-01-01

    Magnetic field (H) sweeping direction dependences of the mixed voltage V{sub mix} induced by the inverse-spin Hall effect(ISHE) and spin-rectified effect (SRE) in a CoFeB (5 nm)/Pt (10 nm) bilayer structure are investigated using the ferromagnetic resonance in the TE mode cavities and coplanar waveguide methods. Conventionally, the magnitude of ISHE voltage V{sub ISH} (symmetric) excluding the SRE (antisymmetric component) was unavoidably separated from the fitting curve of V{sub mix} (a sum of a symmetric and an antisymmetric part) for one direction of H-source. By studying the ratio of the two voltage parts with the bi-directional H sweeping, the optimized V{sub ISH} (no SRE condition) value which also include a well-defined spin Hall angle can be obtained via the linear response relation of ISHE and SRE components. - Highlights: • Hysteretic behavior of ferromagnetic resonance spectra in the CoFeB/Pt sample. • Hysteretic behavior of inverse-spin Hall effect voltage in the CoFeB/Pt sample. • Proportion of inverse spin-Hall effect voltage can be determined by the cavity mode. • The hysteretic behavior arise from the unsaturated magnetization limit. • The well-defined spin Hall angle which consider a hysteresis can be obtained.

  10. Robotics Potential Fields

    Directory of Open Access Journals (Sweden)

    Jordi Lucero

    2009-01-01

    Full Text Available This problem was to calculate the path a robot would take to navigate an obstacle field and get to its goal. Three obstacles were given as negative potential fields which the robot avoided, and a goal was given a positive potential field that attracted the robot. The robot decided each step based on its distance, angle, and influence from every object. After each step, the robot recalculated and determined its next step until it reached its goal. The robot's calculations and steps were simulated with Microsoft Excel.

  11. International Geomagnetic Reference Field

    DEFF Research Database (Denmark)

    Finlay, Chris; Maus, S.; Beggan, C. D.

    2010-01-01

    The eleventh generation of the International Geomagnetic Reference Field (IGRF) was adopted in December 2009 by the International Association of Geomagnetism and Aeronomy Working Group V‐MOD. It updates the previous IGRF generation with a definitive main field model for epoch 2005.0, a main field...... model for epoch 2010.0, and a linear predictive secular variation model for 2010.0–2015.0. In this note the equations defining the IGRF model are provided along with the spherical harmonic coefficients for the eleventh generation. Maps of the magnetic declination, inclination and total intensity...

  12. Room Acoustical Fields

    CERN Document Server

    Mechel, Fridolin

    2013-01-01

    This book presents the theory of room acoustical fields and revises the Mirror Source Methods for practical computational use, emphasizing the wave character of acoustical fields.  The presented higher methods include the concepts of “Mirror Point Sources” and “Corner sources which allow for an excellent approximation of complex room geometries and even equipped rooms. In contrast to classical description, this book extends the theory of sound fields describing them by their complex sound pressure and the particle velocity. This approach enables accurate descriptions of interference and absorption phenomena.

  13. On the Schrodinger field

    International Nuclear Information System (INIS)

    Takahashi, Y.

    1986-01-01

    A brief but systematic discussion of the Schrodinger field is presented from the view point of quantized field theory. It is pointed out that the local momentum conservation equation is not of the usual continuity equation type when two-body potential interaction is presented and nevertheless the total momentum is globally conserved. The Schrodinger equation can be cast into a multicomponent equation containing only first order derivatives, depending on its spin contents. In case of spin 1/2, the g-factor is shown to be 2 even in purely non-relativistic Schrodinger field, in contrast with the general belief that g=2 is a relativistic effect

  14. Ridge and Furrow Fields

    DEFF Research Database (Denmark)

    Møller, Per Grau

    2016-01-01

    Ridge and furrow is a specific way of ploughing which makes fields of systematic ridges and furrows like a rubbing washboard. They are part of an overall openfield system, but the focus in this paper is on the functionality of the fields. There are many indications that agro-technological reasons...... systems and the establishment of basic structures like villages (with churches) and townships and states (in northern Europe). The fields can be considered as a resilient structure lasting for 800 years, along with the same basic physical structures in society....

  15. Geophysical Field Theory

    International Nuclear Information System (INIS)

    Eloranta, E.

    2003-11-01

    The geophysical field theory includes the basic principles of electromagnetism, continuum mechanics, and potential theory upon which the computational modelling of geophysical phenomena is based on. Vector analysis is the main mathematical tool in the field analyses. Electrostatics, stationary electric current, magnetostatics, and electrodynamics form a central part of electromagnetism in geophysical field theory. Potential theory concerns especially gravity, but also electrostatics and magnetostatics. Solid state mechanics and fluid mechanics are central parts in continuum mechanics. Also the theories of elastic waves and rock mechanics belong to geophysical solid state mechanics. The theories of geohydrology and mass transport form one central field theory in geophysical fluid mechanics. Also heat transfer is included in continuum mechanics. (orig.)

  16. Field Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Field Research Facility (FRF) located in Duck, N.C. was established in 1977 to support the U.S. Army Corps of Engineers' coastal engineering mission. The FRF is...

  17. Reversed field pinch diagnostics

    International Nuclear Information System (INIS)

    Weber, P.G.

    1986-01-01

    The Reversed Field Pinch (RFP) is a toroidal, axisymmetric magnetic confinement configuration characterized by a magnetic field configuration in which the toroidal magnetic field is of similar strength to the poloidal field, and is reversed at the edge compared to the center. The RFP routinely operates at high beta, and is a strong candidate for a compact fusion device. Relevant attributes of the configuration will be presented, together with an overview of present and planned experiments and their diagnostics. RFP diagnostics are in many ways similar to those of other magnetic confinement devices (such as tokamaks); these lectures will point out pertinent differences, and will present some diagnostics which provide special insights into unique attributes of the RFP

  18. Algebraic conformal field theory

    International Nuclear Information System (INIS)

    Fuchs, J.; Nationaal Inst. voor Kernfysica en Hoge-Energiefysica

    1991-11-01

    Many conformal field theory features are special versions of structures which are present in arbitrary 2-dimensional quantum field theories. So it makes sense to describe 2-dimensional conformal field theories in context of algebraic theory of superselection sectors. While most of the results of the algebraic theory are rather abstract, conformal field theories offer the possibility to work out many formulae explicitly. In particular, one can construct the full algebra A-bar of global observables and the endomorphisms of A-bar which represent the superselection sectors. Some explicit results are presented for the level 1 so(N) WZW theories; the algebra A-bar is found to be the enveloping algebra of a Lie algebra L-bar which is an extension of the chiral symmetry algebra of the WZW theory. (author). 21 refs., 6 figs

  19. Earth's Magnetic Field

    DEFF Research Database (Denmark)

    This volume provides a comprehensive view on the different sources of the geomagnetic field both in the Earth’s interior and from the field’s interaction with the terrestrial atmosphere and the solar wind. It combines expertise from various relevant areas of geomagnetic and near Earth space...... research with the aim to better characterise the state and dynamics of Earth’s magnetic field. Advances in the exploitation of geomagnetic observations hold a huge potential not only for an improved quantitative description of the field source but also for a better understanding of the underlying processes...... and space observations, and on state-of-the-art empirical models and physics-based simulations. Thus, it provides an in-depth overview over recent achievements, current limitations and challenges, and future opportunities in the field of geomagnetism and space sciences....

  20. The master field revisited

    International Nuclear Information System (INIS)

    Gopakumar, R.

    1996-01-01

    We review recent work on the master field in large N theories. In particular the mathematical framework appropriate for its construction is sketched. The calculational utility of this framework is demonstrated in the case of QCD 2 . (orig.)

  1. Field Geology/Processes

    Science.gov (United States)

    Allen, Carlton; Jakes, Petr; Jaumann, Ralf; Marshall, John; Moses, Stewart; Ryder, Graham; Saunders, Stephen; Singer, Robert

    1996-01-01

    The field geology/process group examined the basic operations of a terrestrial field geologist and the manner in which these operations could be transferred to a planetary lander. Four basic requirements for robotic field geology were determined: geologic content; surface vision; mobility; and manipulation. Geologic content requires a combination of orbital and descent imaging. Surface vision requirements include range, resolution, stereo, and multispectral imaging. The minimum mobility for useful field geology depends on the scale of orbital imagery. Manipulation requirements include exposing unweathered surfaces, screening samples, and bringing samples in contact with analytical instruments. To support these requirements, several advanced capabilities for future development are recommended. Capabilities include near-infrared reflectance spectroscopy, hyper-spectral imaging, multispectral microscopy, artificial intelligence in support of imaging, x ray diffraction, x ray fluorescence, and rock chipping.

  2. Maine Field Station

    Data.gov (United States)

    Federal Laboratory Consortium — In 2000 NOAA's National Marine Fisheries Service established the Maine Field Station in Orono, ME to have more direct involvement in the conservation of the living...

  3. Three dimensional field computation

    International Nuclear Information System (INIS)

    Trowbridge, C.W.

    1981-06-01

    Recent research work carried out at Rutherford and Appleton Laboratories into the Computation of Electromagnetic Fields is summarised. The topics covered include algorithms for integral and differential methods for the solution of 3D magnetostatic fields, comparison of results with experiment and an investigation into the strengths and weaknesses of both methods for an analytic problem. The paper concludes with a brief summary of the work in progress on the solution of 3D eddy currents using differential finite elements. (author)

  4. Magnetic field of Mercury

    International Nuclear Information System (INIS)

    Jackson, D.J.; Beard, D.B.

    1977-01-01

    The geomagnetic field, suitably scaled down and parameterized, is shown to give a very good fit to the magnetic field measurements taken on the first and third passes of the Mariner 10 space probe past Mercury. The excellence of the fit to a reliable planetary magnetospheric model is good evidence that the Mercury magnetosphere is formed by a simple, permanent, intrinsic planetary magnetic field distorted by the effects of the solar wind. The parameters used for a best fit to all the data are (depending slightly on the choice of data) 2.44--2.55 for the ratio of Mercury's magnetic field strength at the subsolar point to that of the earth's subsolar point field (this results in a dipole moment of 170 γR/sub M/ 3 (R/sub M/ is Mercury Radius), i.e., 2.41 x 10 22 G cm 3 in the same direction as the earth's dipole), approx.-113 γR/sub M/ 4 for the planetary quadrupole moment parallel to the dipole moment, 10degree--17degree for the tilt of the planet dipole toward the sun, 4.5degree for the tilt of the dipole toward dawn, and 2.5degree--7.6degree aberration angle for the shift in the tail axis from the planet-sun direction because of the planet's orbital velocity. The rms deviation overall for the entire data set compared with the theoretical fitted model for the magnetic field strength was 17 γ (approx.4% of the maximum field measured). If the data from the first pass that show presumed strong time variations are excluded, the overall rms deviation for the field magnitude is only 10 γ

  5. Magnetic field dosimeter development

    International Nuclear Information System (INIS)

    Lemon, D.K.; Skorpik, J.R.; Eick, J.L.

    1980-09-01

    In recent years there has been increased concern over potential health hazards related to exposure of personnel to magnetic fields. If exposure standards are to be established, then a means for measuring magnetic field dose must be available. To meet this need, the Department of Energy has funded development of prototype dosimeters at the Battelle Pacific Northwest Laboratory. This manual reviews the principle of operation of the dosimeter and also contains step-by-step instructions for its operation

  6. DSM-5 field survey

    DEFF Research Database (Denmark)

    Lochner, Christine; Grant, Jon E; Odlaug, Brian Lawrence

    2012-01-01

    The aim of this multisite field survey was to examine the DSM-IV-TR criteria, proposed DSM-5 diagnostic criteria, as well as a number of possible additional diagnostic criteria, in patients with hair-pulling disorder (HPD, or trichotillomania).......The aim of this multisite field survey was to examine the DSM-IV-TR criteria, proposed DSM-5 diagnostic criteria, as well as a number of possible additional diagnostic criteria, in patients with hair-pulling disorder (HPD, or trichotillomania)....

  7. Collective field accelerator

    International Nuclear Information System (INIS)

    Luce, J.S.

    1978-01-01

    A collective field accelerator which operates with a vacuum diode and utilizes a grooved cathode and a dielectric anode that operates with a relativistic electron beam with a ν/γ of approx. 1, and a plurality of dielectric lenses having an axial magnetic field thereabout to focus the collectively accelerated electrons and ions which are ejected from the anode. The anode and lenses operate as unoptimized r-f cavities which modulate and focus the beam

  8. Controlling magnetic field profiles

    International Nuclear Information System (INIS)

    Freeman, J.R.

    1979-04-01

    A method for designing solenoid magnets with controlled field profiles is discussed. The method, originated by D.B. Montgomery, minimizes both the field errors and the power consumption. An NOS time-sharing computer program for the CDC-6600, entitled MAGCOR, was constructed to provide an interactive magnet design capability. Results obtained during the design of magnets for a radial line electron accelerator are presented. 9 figures

  9. Gauge field theories

    International Nuclear Information System (INIS)

    Leite Lopes, J.

    1981-01-01

    The book is intended to explain, in an elementary way, the basic notions and principles of gauge theories. Attention is centred on the Salem-Weinberg model of electro-weak interactions, as well as neutrino-lepton scattering and the parton model. Classical field theory, electromagnetic, Yang-Mills and gravitational gauge fields, weak interactions, Higgs mechanism and the SU(5) model of grand unification are also discussed. (U.K.)

  10. Pulsed and Static Neutron Measurements in Light-Water and Heavy-Water Exponentials; Mesures par les Methodes Pulsee et Statique dans les Ensembles Exponentiels a Eau Legere et a Eau Lourde; Izmerenie impul'snykh i staticheskikh nejtronov v ehksponentsial'nykh ustanovkakh s obychnoj i tyazheloj vodoj; Mediciones por los Metodos Pulsados y Estaticos en Conjuntos Exponenciales de Agua Ligera y Agua Pesada

    Energy Technology Data Exchange (ETDEWEB)

    Parkinson, T. F.; Perez, R. B.; Fry, D. N.; Hartley, R. H.; Smith, S. P.D.; Diaz, N. J. [University of Florida, Gainesville, FL (United States)

    1964-04-15

    etant le laplacien geometrique du systeme equivalent sans reflecteur avec gain reflecteur. Modele C: On imagine un systeme sans reflecteur a deux groupes avec gain reflecteur. En comparant les constantes de decroissance obtenues par calcul et par voie experimentale, on constate que seul le modele A assure une concordance satisfaisante. On peut en tirer les conclusions ci-apres: 1. La presence du reflecteur a una grande influence sur la physique du systeme puise. L'hypothese selon laquelle on admet un gain reflecteur n'est pas toujours valable. 2. La valeur de la constante de decroissance {lambda} depend etroitement de la valeur admise pour la probabilite d'absence de fuite de neutrons rapides. Les experiences indiquent que la methode des neutrons puises permet de determiner k{sub {infinity}} pour des ensembles heterogenes de petites dimensions. Des travaux sont en cours sur des barres d'uranium creuses qui permettent de simuler l'emploi de fluides de refroidissement organiques. (author) [Spanish] Desde hace tiempo se recurre a experimentos exponenciales para determinar el laplaciano material de un medio multiplicador. En fecha mas reciente se ha comenzado a utilizar la tecnica de los neutrones pulsados para medir los valores propios del tiempo, {lambda}, de los que puede deducirse k{sub {infinity}}. Este ultimo metodo presenta la ventaja de que permite el empleo de reticulados mas pequefios que el metodo exponencial estatico. Sin embargo, para establecer la validez del metodo pulsado, es preciso comparar sus resultados con los obtenidos mediante los metodo estaticos. Los autores han efectuado estas mediciones en sistemas con y sin reflector, utilizando H{sub 2}O y D{sub 2}O en calidad de moderador; en los experimentos emplearon un tanque de 1 m de diametro. La correlacion entre las constantes de decrecimiento medidas y los parametros pertinentes del sistema se efectuo empleando un modelo teorico modificado de un solo grupo (denominado modelo A). El valor de {lambda} se

  11. Radial Field Piezoelectric Diaphragms

    Science.gov (United States)

    Bryant, R. G.; Effinger, R. T., IV; Copeland, B. M., Jr.

    2002-01-01

    A series of active piezoelectric diaphragms were fabricated and patterned with several geometrically defined Inter-Circulating Electrodes "ICE" and Interdigitated Ring Electrodes "ICE". When a voltage potential is applied to the electrodes, the result is a radially distributed electric field that mechanically strains the piezoceramic along the Z-axis (perpendicular to the applied electric field). Unlike other piezoelectric bender actuators, these Radial Field Diaphragms (RFDs) strain concentrically yet afford high displacements (several times that of the equivalent Unimorph) while maintaining a constant circumference. One of the more intriguing aspects is that the radial strain field reverses itself along the radius of the RFD while the tangential strain remains relatively constant. The result is a Z-deflection that has a conical profile. This paper covers the fabrication and characterization of the 5 cm. (2 in.) diaphragms as a function of poling field strength, ceramic thickness, electrode type and line spacing, as well as the surface topography, the resulting strain field and displacement as a function of applied voltage at low frequencies. The unique features of these RFDs include the ability to be clamped about their perimeter with little or no change in displacement, the environmentally insulated packaging, and a highly repeatable fabrication process that uses commodity materials.

  12. Field reversal experiments (FRX)

    International Nuclear Information System (INIS)

    Linford, R.K.; Armstrong, W.T.; Platts, D.A.; Sherwood, E.G.

    1978-01-01

    The equilibrium, confinement, and stability properties of the reversed-field configuration (RFC) are being studied in two theta-pinch facilities. The RFC is an elongated toroidal plasma confined in a purely poloidal field geometry. The open field lines of the linear theta pinch support the closed-field RFC much like the vertical field centers the toroidal plasma in a tokamak. Depending on stability and confinement properties, the RFC might be used to greatly reduce the axial losses in linear fusion devices such as mirrors, theta pinches, and liners. The FRX systems produce RFC's with a major radius R = 2-6 cm, minor radius a approximately 2 cm, and a total length l approximately 35 cm. The observed temperatures are T/sub e/ approximately 100 eV and T/sub i/ = 150-350 eV with a peak density n approximately 2 x 10 15 cm -3 . After the plasma reaches equilibrium, the RFC remains stable for up to 30 μs followed by the rapid growth of the rotational m = 2 instability, which terminates the confinement. During the stable equilibrium, the particle and energy confinement times are more than 10 times longer than in an open-field system. The behavior of the m = 2 mode qualitatively agrees with the theoretically predicted instability for rotational velocities exceeding some critical value

  13. Field reversal experiments (FRX)

    International Nuclear Information System (INIS)

    Linford, R.K.; Armstrong, W.T.; Platts, D.A.; Sherwood, E.G.

    1979-01-01

    The equilibrium, confinement, and stability properties of the reversed-field configuration (RFC) are being studied in two theta-pinch facilities. The RFC is an elongated toroidal plasma confined in a purely poloidal field geometry. The open field lines of the linear theta pinch support the closed-field RFC much like the vertical field centres the toroidal plasma in a tokamak. Depending on stability and confinement properties, the RFC might be used to greatly reduce the axial losses in linear fusion devices such as mirrors, theta pinches, and liners. The FRX systems produce RFCs with a major radius R=2-6cm, a minor radius a approximately 2cm, and a total length l approximately 35cm. The observed temperatures are Tsub(e) approximately 100eV and Tsub(i)=150-350eV with a peak density n approximately 2x10 15 cm -3 . After the plasma has reached equilibrium, the RFC remains stable for up to 30μs, followed by the rapid growth of the rotational m=2 instability, which terminates the confinement. During the stable equilibrium, the particle and energy confinement times are more than 10 times longer than in an open-field system. The behaviour of the m=2 mode agrees qualitatively with the theoretically predicted instability for rotational velocities exceeding some critical value. (author)

  14. Magnetic field screens

    International Nuclear Information System (INIS)

    Mansfield, P.; Turner, R.; Chapman, B.L.W.; Bowley, R.M.

    1990-01-01

    A screen for a magnetic coil, for producing, for example, a homogeneous, gradient or RF field in nuclear magnetic resonance imaging, is described. It is provided by surround the coil with a set of electrical conductors. The currents within the conductors are controlled in such a manner that the field is neutralised in a specific region of space. The current distribution within the conductors is determined by calculating the current within a hypothetical superconductive shield which would have the effect of neutralising the field, the current through the conductors thereby being a substitute for the superconductive shield. The conductors may be evenly spaced and connected in parallel, their resistances being determined by thickness or composition to provide the desired current, or they may carry equal currents but be differently spaced. A further set or sets of controlled conductors outside the first set may ensure that the first set does not upset the field from the NMR coil. The shield may selectively reflect certain fields while transmitting others and may prevent acoustic vibration e.g. when switching gradient fields. An RF coil arrangement may consist of two orthogonal coils, one coil within the other for use as a transmit/receive set or as a double resonance transmitter; a shield between the coils is in series with, and formed from the same winding as, the inner coil. (author)

  15. CONSERVACION DE MANZANAS GRANNY SMITH MINIMAMENTE PROCESADAS POR METODOS COMBINADOS

    OpenAIRE

    GALLEGUILLOS CANALES, PAMELA CRISTINA; GALLEGUILLOS CANALES, PAMELA CRISTINA

    2011-01-01

    Se ha demostrado que el consumo de frutas y hortalizas tiene un efecto beneficioso para la salud. Debido a su alto contenido de antioxidantes, constituye una de las maneras más efectivas para reducir el riesgo de enfermedades crónicas no transmisibles (Speisky, 2006; Block et al., 1992; Knekt et al., 1997; Ness y Powles, 1997; Doll, 1990; Wang et al., 1996; Del Caro et al., 2004). El aumento de muertes por enfermedades como cáncer, diabetes y enfermedades cardiovasculares, ha llevado a ent...

  16. Il metodo della fisica e le problematiche della biologia

    Directory of Open Access Journals (Sweden)

    Tripodi, G

    2007-07-01

    Full Text Available Following the ancient Hermetic aphorism solve et coagula, we investigate the nature of the interface between physics and biology by moving up and down the different temporal and spatial scales which enter the description of natural phenomena. Various indications seem to support both the existence of such an interface and the possibility of finding methods, languages, and targets shared by such two disciplines. However, this possibility becomes remote if one moves further and further from the microscopic level of atoms and molecules (and, correspondingly, of molecular biology. We conclude that the biologically founded epistemology proposed by Maturana and Varela as well as cultural anthropology and sociology cannot yet be treated with the methodology of physics.

  17. Il metodo di Aristarco à solo un modello?

    Science.gov (United States)

    Sigismondi, Costantino; Agolini, Giorgia

    2017-06-01

    The method of Aristarchus of Samo to measure the distance Earth-Sun is well known as the first step in the cosmological distance ladder. Our task is to understand if it is worth to repeat it also experimentally, with positive conclusions, especially with respect to the experimental design.

  18. Ensenanza de la Astronomia a Traves de Metodos no Tradicionales

    Science.gov (United States)

    Tignanelli, H. L.

    1990-11-01

    REUMEN: Se presentan los aspects pri nc ipales de a ense? anza de la astronor:. a para -; s. En esta cc .unicaci #n, 5 ha especial mfasis em Ia descripci':"n de las caracteristicas y las posibi lidades peda gicas de los no tradicionales de aprendiZaje. E' : In the following the principal aspects of teaching of astrono ..y for children) are oresented. In this paper, special emphasis has been given to desc rib the characteristics and pedagogical possibilities of the non traditional methods of learning. : TEACHING

  19. El Metodo Llamado Proyecto (The Project Approach). ERIC Digest.

    Science.gov (United States)

    Katz, Lilian G.

    A project is an in-depth investigation of a topic worth learning more about, usually undertaken by a group of children within a class. The goal of a project is to learn more about a topic rather than to find answers to questions posed by a teacher. Project work is complementary to the systematic parts of a curriculum. Whereas systematic…

  20. A {beta} - {gamma} coincidence; Metodo de coincidencias {beta} - {gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Agullo, F

    1960-07-01

    A {beta} - {gamma} coincidence method for absolute counting is given. The fundamental principles are revised and the experimental part is detailed. The results from {sup 1}98 Au irradiated in the JEN 1 Swimming pool reactor are given. The maximal accuracy is 1 per cent. (Author) 11 refs.

  1. Impacto orcamentario da utilizacao do Metodo Canguru no cuidado neonatal

    Directory of Open Access Journals (Sweden)

    Aline Piovezan Entringer

    2013-10-01

    Full Text Available OBJETIVO Estimar o impacto orçamentário da utilização do Método Canguru na rede municipal de saúde. MÉTODOS Um modelo de decisão analítico foi desenvolvido para simular os custos do Método Canguru e Unidade Intermediária Neonatal no Rio de Janeiro, RJ, em 2011. A população de referência foi constituída pelos recém-nascidos estáveis clinicamente, que podem receber assistência nas duas modalidades de cuidado. O impacto orçamentário foi estimado para uma coorte hipotética de 1.000 recém-nascidos elegíveis em um ano. A proporção de recém-nascidos elegíveis que recebem assistência nas duas modalidades foi obtida por coleta de dados nas maternidades incluídas no estudo. As probabilidades dos eventos e o consumo de recursos de saúde, no período da assistência, foram incorporados ao modelo. Cenários foram desenvolvidos para refletir a adoção do método Canguru em maior ou menor escala. RESULTADOS A utilização do Método Canguru significou redução de gastos equivalente a 16% em um ano, se todos os recém-nascidos elegíveis fossem assistidos por esse método. CONCLUSÕES A opção Método Canguru é de menor custo comparado com a da Unidade Intermediária Neonatal. A análise de impacto orçamentário da utilização desse método no Sistema Único de Saúde indicou economia importante para o período de um ano.

  2. Per una teoria generale (disgiunta ma unificata del metodo

    Directory of Open Access Journals (Sweden)

    Mario Gennari

    2015-12-01

    Full Text Available What is a general methodology of science? What is a general theory of method? The article examines the two questions and summarizes the passages that connect – not only in a separate but also in a unified way – recognition, understanding, reasoning and abduction. Then induction, deduction, explanation and interpretation, in order to come finally to the meaning of fact. The general theory of method not divides the natural sciences, but blend them in an unitary project.

  3. Adaptyvaus 2d pozicionavimo metodo autonominiam robotui tyrimas

    OpenAIRE

    Senvaitis, Vytautas

    2016-01-01

    Overview SLAM algorithm, laser distance scanner working principle, EKF and UKF filters in analytical part. EKF mathematical models are implemented for autonomous robot whit two-wheel drive and for laser distance scanner. EKF and UKF filters are compared. 2D robot positioning with EKF filter are modeled and simulated in MATALB and STM32 microcontroller with DSP library. MATLAB and STM32 are compared in speed test. Analyzing EKF filter working. Design and construct autonomous robot experimental...

  4. Magnetic fields at Neptune

    International Nuclear Information System (INIS)

    Ness, N.F.; Acuna, M.H.; Burlaga, L.F.; Connerney, J.E.P.; Lepping, R.P.; Neubauer, F.M.

    1989-01-01

    The National Aeronautics and Space Administration Goddard Space Flight Center-University of Delaware Bartol Research Institute magnetic field experiment on the Voyager 2 spacecraft discovered a strong and complex intrinsic magnetic field of Neptune and an associated magnetosphere and magnetic tail. A maximum magnetic field of nearly 10,000 nanoteslas (1 nanotesla = 10 -5 gauss) was observed near closest approach, at a distance of 1.18 R N . The planetary magnetic field between 4 and 15 R N can be well represented by an offset tilted magnetic dipole (OTD), displaced from the center of Neptune by the surprisingly large amount of 0.55 R N and inclined by 47 degrees with respect to the rotation axis. Within 4 R N , the magnetic field representation must include localized sources or higher order magnetic multipoles, or both, which are not yet well determined. As the spacecraft exited the magnetosphere, the magnetic tail appeared to be monopolar, and no crossings of an imbedded magnetic field reversal or plasma neutral sheet were observed. The auroral zones are most likely located far from the rotation poles and may have a complicated geometry. The rings and all the known moons of Neptune are imbedded deep inside the magnetosphere, except for Nereid, which is outside when sunward of the planet. The radiation belts will have a complex structure owing to the absorption of energetic particles by the moons and rings of Neptune and losses associated with the significant changes in the diurnally varying magnetosphere configuration. In an astrophysical context, the magnetic field of Neptune, like that of Uranus, may be described as that of an oblique rotator

  5. Magnetic Fields Versus Gravity

    Science.gov (United States)

    Hensley, Kerry

    2018-04-01

    Deep within giant molecular clouds, hidden by dense gas and dust, stars form. Unprecedented data from the Atacama Large Millimeter/submillimeter Array (ALMA) reveal the intricate magnetic structureswoven throughout one of the most massive star-forming regions in the Milky Way.How Stars Are BornThe Horsehead Nebulasdense column of gas and dust is opaque to visible light, but this infrared image reveals the young stars hidden in the dust. [NASA/ESA/Hubble Heritage Team]Simple theory dictates that when a dense clump of molecular gas becomes massive enough that its self-gravity overwhelms the thermal pressure of the cloud, the gas collapses and forms a star. In reality, however, star formation is more complicated than a simple give and take between gravity and pressure. Thedusty molecular gas in stellar nurseries is permeated with magnetic fields, which are thought to impede the inward pull of gravity and slow the rate of star formation.How can we learn about the magnetic fields of distant objects? One way is by measuring dust polarization. An elongated dust grain will tend to align itself with its short axis parallel to the direction of the magnetic field. This systematic alignment of the dust grains along the magnetic field lines polarizes the dust grains emission perpendicular to the local magnetic field. This allows us to infer the direction of the magnetic field from the direction of polarization.Magnetic field orientations for protostars e2 and e8 derived from Submillimeter Array observations (panels a through c) and ALMA observations (panels d and e). Click to enlarge. [Adapted from Koch et al. 2018]Tracing Magnetic FieldsPatrick Koch (Academia Sinica, Taiwan) and collaborators used high-sensitivity ALMA observations of dust polarization to learn more about the magnetic field morphology of Milky Way star-forming region W51. W51 is one of the largest star-forming regions in our galaxy, home to high-mass protostars e2, e8, and North.The ALMA observations reveal

  6. Productive fluid intervals in wells H-35 and H-39, Los Humeros geothermal field, Puebla (Mexico); Intervalos productores de fluidos en los pozos H-35 y H-39 del campo geotermico Los Humeros, Puebla, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Medina Martinez, Moises [Comision Federal de Electridad, Perote, Veracruz (Mexico)

    2000-12-01

    This paper presents the results of log interpretations using the percentage method to define the productive fluid intervals in wells H-35 and H-39. These were identified with pressure, temperature and flow rate (PTS) electronic logs, used for the first time in this field. The test were carried out with the well integrated to the electrical generation units. Well H-35 fed steam to Units 1, 4, 5 and 7 through a plate with a restriction orifice diameter of 50.8 mm (2 inches), a well head pressure of 45 bars and a mass flow rate of 40 t/h. Well H-39 fed steam to Unit 3 through plate with a restriction orifice diameter of 50.8 mm (2 inches), a well head pressure of 27 bars and a mass flow rate of 30 t/h. [Spanish] Se presenta la intervencion realizada por el metodo de porcentajes para definir los intervalos productores de fluidos en los pozos H-35 y H-39. El estudio se hizo a partir de datos obtenidos con una sonda electronica de presion, temperatura y velocidad de flujo (PTS), utilizada por primera vez en este campo. En ambos casos se realizaron las pruebas con el pozo integrado a las unidades de generacion electrica, el primero suministra vapor para las Unidades 1, 4, 5 y 7 a traves de una placa de orificio de restriccion de 50.8 mm (2 pulgadas) de diametro, con presion de cabezal de 45 bar manometricos y un gasto de mezcla de 40 t/h. El segundo alimenta a la Unidad 3, fluye por orificio de 50.8 mm (2 pulgadas) de diametro y produce 30 t/h de mezcla con una presion en la cabeza de 27 bar.

  7. Theoretical physics. Field theory

    International Nuclear Information System (INIS)

    Landau, L.; Lifchitz, E.

    2004-01-01

    This book is the fifth French edition of the famous course written by Landau/Lifchitz and devoted to both the theory of electromagnetic fields and the gravity theory. The talk of the theory of electromagnetic fields is based on special relativity and relates to only the electrodynamics in vacuum and that of pointwise electric charges. On the basis of the fundamental notions of the principle of relativity and of relativistic mechanics, and by using variational principles, the authors develop the fundamental equations of the electromagnetic field, the wave equation and the processes of emission and propagation of light. The theory of gravitational fields, i.e. the general theory of relativity, is exposed in the last five chapters. The fundamentals of the tensor calculus and all that is related to it are progressively introduced just when needed (electromagnetic field tensor, energy-impulse tensor, or curve tensor...). The worldwide reputation of this book is generally allotted to clearness, to the simplicity and the rigorous logic of the demonstrations. (A.C.)

  8. Field error lottery

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, C.J.; McVey, B. (Los Alamos National Lab., NM (USA)); Quimby, D.C. (Spectra Technology, Inc., Bellevue, WA (USA))

    1990-01-01

    The level of field errors in an FEL is an important determinant of its performance. We have computed 3D performance of a large laser subsystem subjected to field errors of various types. These calculations have been guided by simple models such as SWOOP. The technique of choice is utilization of the FELEX free electron laser code that now possesses extensive engineering capabilities. Modeling includes the ability to establish tolerances of various types: fast and slow scale field bowing, field error level, beam position monitor error level, gap errors, defocusing errors, energy slew, displacement and pointing errors. Many effects of these errors on relative gain and relative power extraction are displayed and are the essential elements of determining an error budget. The random errors also depend on the particular random number seed used in the calculation. The simultaneous display of the performance versus error level of cases with multiple seeds illustrates the variations attributable to stochasticity of this model. All these errors are evaluated numerically for comprehensive engineering of the system. In particular, gap errors are found to place requirements beyond mechanical tolerances of {plus minus}25{mu}m, and amelioration of these may occur by a procedure utilizing direct measurement of the magnetic fields at assembly time. 4 refs., 12 figs.

  9. Multi-valued fields

    CERN Document Server

    Ershov, Yuri L

    2001-01-01

    For more than 30 years, the author has studied the model-theoretic aspects of the theory of valued fields and multi-valued fields. Many of the key results included in this book were obtained by the author whilst preparing the manuscript. Thus the unique overview of the theory, as developed in the book, has been previously unavailable. The book deals with the theory of valued fields and mutli-valued fields. The theory of Prüfer rings is discussed from the `geometric' point of view. The author shows that by introducing the Zariski topology on families of valuation rings, it is possible to distinguish two important subfamilies of Prüfer rings that correspond to Boolean and near Boolean families of valuation rings. Also, algebraic and model-theoretic properties of multi-valued fields with near Boolean families of valuation rings satisfying the local-global principle are studied. It is important that this principle is elementary, i.e., it can be expressed in the language of predicate calculus. The most important...

  10. Electromagnetic fields and cancer

    International Nuclear Information System (INIS)

    Singh, Neeta; Mathur, R.; Behari, J.

    1997-01-01

    Several studies in recent years have raised the possibility that exposure to electromagnetic fields (EMFs) may be hazardous to human health, in particular by promotion or initiation of cancer. Recent reports have indicated increased cancer risk from industrial and domestic exposure to environmental ELF fields and to RF fields that are amplitude modulated at ELF. EMF fields have been reported to affect biological systems in various ways, affecting changes in the morphology and or functional behavior of cells, which have been observed in a variety of tissues. Although the mechanism of interaction of EMFs with living cells are not known, it has been proposed that they have multiple effects and can affect cell signalling, including modification of plasma membrane permeability and ion transport. Our findings suggest that EMFs can affect post translational modification of proteins such as poly ADP-ribosylation by epigenetic mechanism and that the effect of EMFs are highly specific regarding both the cell type and the frequency and amplification of the applied field. (author)

  11. String field theory

    International Nuclear Information System (INIS)

    Kaku, M.

    1987-01-01

    In this article, the authors summarize the rapid progress in constructing string field theory actions, such as the development of the covariant BRST theory. They also present the newer geometric formulation of string field theory, from which the BRST theory and the older light cone theory can be derived from first principles. This geometric formulation allows us to derive the complete field theory of strings from two geometric principles, in the same way that general relativity and Yang-Mills theory can be derived from two principles based on global and local symmetry. The geometric formalism therefore reduces string field theory to a problem of finding an invariant under a new local gauge group they call the universal string group (USG). Thus, string field theory is the gauge theory of the universal string group in much the same way that Yang-Mills theory is the gauge theory of SU(N). The geometric formulation places superstring theory on the same rigorous group theoretical level as general relativity and gauge theory

  12. New Methods and Facilities for the Measurement of Physical Properties of Reactor Components and Irradiated Materials; Nouveaux Procedes et Instruments de Mesure des Proprietes Physiques des Elements de Reacteur et des Matieres Irradiees; Novye metody i sredstva izmereniya fizicheskikh s vojstv komponentov reaktora i obluchennykh materialov; Nuevos Metodos y Equipos para Medir Propiedades Fisicas de Componentes de Reactor y de Materiales Irradiados

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, F.; Mueller, P. [Institut Dr. Foerster, Reutlingen, Federal Republic of Germany (Germany)

    1965-09-15

    zone 'chaude ' du reacteur. Ils discutent la relation entre la conductivite electrique et la dose d'irradiation. Les auteurs decrivent un instrument de mesure de la permeabilite, de la remanence et de la force co- ercitive en fonction des contraintes mecaniques, de la deformation elastique et inelastique et de la dose d'irradiation. Ils donnent des mesures de la variation des proprietes magnetiques en fonction des contraintes elastiques et de la deformation inelastique. Ils etudient les effets de l'irradiation sur la permeabilite et sur la force coercitive. Les auteurs decrivent un instrument permettant la mesure rapide et la lecture directe de la permeabilite des elements en acier inoxydable. Ils expliquent la correlation entre la permeabilite et la teneur en ferrite {Delta}. Us discutent certaines mesures du pourcentage de ferrite {Delta} dans les soudures de tubes en acier inoxydable ainsi que certaines mesures de precipitation de ferrite {Delta} en fonction de la deformation inelastique (forgeage a la main d'elements combustibles pour reacteurs). (author) [Spanish] Se describe un intrumento para medir y registrar en forma totalmente automatica el modulo de Young, el modulodecorte y la capacidad de amortiguamiento, en funcion de la temperatura y el tiempo. El modulo de Young se determina excitando muestras de diversos tamanos con sus frecuencias naturales, mientras que la capacidad de amortiguamiento se mide en funcion de la libre atenuacion de la vibracion, o bien por la anchura media de la curva de resonancia. Se presentan ejemplos de medidas de la recuperacion despues de provocar danos por irradiaciones y deformaciones plasticas asf como grado de grafitacion. Se describe la deteccion de fallas y variaciones de densidad en barras de grafito. Se explica, ademas, un metodo para investigar la retencion de pastillas de UO{sub 2} en tubos austenfticos de pared delgada. Se describe un horno especial para estudiar el comportamiento elastico e inelastico de muestras

  13. Cosmic magnetic fields

    CERN Document Server

    Kronberg, Philipp P

    2016-01-01

    Magnetic fields are important in the Universe and their effects contain the key to many astrophysical phenomena that are otherwise impossible to understand. This book presents an up-to-date overview of this fast-growing topic and its interconnections to plasma processes, astroparticle physics, high energy astrophysics, and cosmic evolution. The phenomenology and impact of magnetic fields are described in diverse astrophysical contexts within the Universe, from galaxies to the filaments and voids of the intergalactic medium, and out to the largest redshifts. The presentation of mathematical formulae is accessible and is designed to add insight into the broad range of topics discussed. Written for graduate students and researchers in astrophysics and related disciplines, this volume will inspire readers to devise new ways of thinking about magnetic fields in space on galaxy scales and beyond.

  14. Nonlocal quantum field theory

    International Nuclear Information System (INIS)

    Efimov, G.V.

    1976-01-01

    The basic ideas for creating the theory of nonlocal interactions of a scalar one-component field are presented. Lagrangian describing a non-interacting field is the ordinary one so that non-interacting particles are described by standard methods of the Fock space. Form factors introduced have been chosen from a class of analytic functionals and quantized. Conditions of microcausality have been considered in detail. The convergence of all integrals corresponding to the arbitrary Feynman diagrams in spinor electrodynamics is guaranteed in the frame of the rules formulated. It is noted in conclusion that the spinor electrodynamics with nonlocal interaction contains no ultraviolet divergencies and satisfies all the requirements of the quantum field theory; in this sense it is mathematically more consistent than its local version

  15. Collinear wake field acceleration

    International Nuclear Information System (INIS)

    Bane, K.L.F.; Chen, P.; Wilson, P.B.

    1985-04-01

    In the Voss-Weiland scheme of wake field acceleration a high current, ring-shaped driving bunch is used to accelerate a low current beam following along on axis. In such a structure, the transformer ratio, i.e., the ratio of maximum voltage that can be gained by the on-axis beam and the voltage lost by the driving beam, can be large. In contrast, it has been observed that for an arrangement in which driving and driven bunches follow the same path, and where the current distribution of both bunches is gaussian, the transformer ratio is not normally greater than two. This paper explores some of the possibilities and limitations of a collinear acceleration scheme. In addition to its application to wake field acceleration in structures, this study is also of interest for the understanding of the plasma wake field accelerator. 11 refs., 4 figs

  16. Gyrokinetic field theory

    International Nuclear Information System (INIS)

    Sugama, H.

    1999-08-01

    The Lagrangian formulation of the gyrokinetic theory is generalized in order to describe the particles' dynamics as well as the self-consistent behavior of the electromagnetic fields. The gyrokinetic equation for the particle distribution function and the gyrokinetic Maxwell's equations for the electromagnetic fields are both derived from the variational principle for the Lagrangian consisting of the parts of particles, fields, and their interaction. In this generalized Lagrangian formulation, the energy conservation property for the total nonlinear gyrokinetic system of equations is directly shown from the Noether's theorem. This formulation can be utilized in order to derive the nonlinear gyrokinetic system of equations and the rigorously conserved total energy for fluctuations with arbitrary frequency. (author)

  17. Electromagnetic fields and life

    CERN Document Server

    Presman, A S

    1970-01-01

    A broad region of the electromagnetic spectrum long assumed to have no influence on living systems under natural conditions has been critically re-examined over the past decade. This spectral region extends from the superhigh radio frequencies, through de­ creasing frequencies, to and including essentially static electric and magnetic fields. The author of this monograph, A. S. Presman, has reviewed not only the extensive Russian literatur!;"l, but also al­l most equally comprehensively the non-Russian literature, dealing with biological influences of these fields. Treated also is literature shedding some light on possible theoretical foundations for these phenomena. A substantial, rapidly increasing number of studies in many laboratories and countries has now clearly established bio­ logical influences which are independent of the theoretically predictable, simple thermal effects. Indeed many of the effects are produced by field strengths very close to those within the natural environment. The author has,...

  18. Electromagnetic fields and waves

    CERN Document Server

    Iskander, Magdy F

    2013-01-01

    The latest edition of Electromagnetic Fields and Waves retains an authoritative, balanced approach, in-depth coverage, extensive analysis, and use of computational techniques to provide a complete understanding of electromagnetic—important to all electrical engineering students. An essential feature of this innovative text is the early introduction of Maxwell's equations, together with the quantifying experimental observations made by the pioneers who discovered electromagnetics. This approach directly links the mathematical relations in Maxwell's equations to real experiments and facilitates a fundamental understanding of wave propagation and use in modern practical applications, especially in today's wireless world. New and expanded topics include the conceptual relationship between Coulomb's law and Gauss's law for calculating electric fields, the relationship between Biot-Savart's and Ampere's laws and their use in calculating magnetic fields from current sources, the development of Faraday's law from e...

  19. Supersymmetric gauge field theories

    International Nuclear Information System (INIS)

    Slavnov, A.A.

    1976-01-01

    The paper is dealing with the role of supersymmetric gauge theories in the quantum field theory. Methods of manipulating the theories as well as possibilities of their application in elementary particle physics are presented. In particular, the necessity is explained of a theory in which there is symmetry between Fermi and Bose fields, in other words, of the supersymmetric gauge theory for construction of a scheme for the Higgs particle connecting parameters of scalar mesons with those of the rest fields. The mechanism of supersymmetry breaking is discussed which makes it possible to remain the symmetric procedure of renormalization intact. The above mechanism of spontaneous symmetry breaking is applied to demonstrate possibilities of constructing models of weak and electromagnetic interactions which would be acceptable from the point of view of experiments. It is noted that the supersymmetric gauge theories represent a natural technique for description of vector-like models

  20. Reversed field pinch experiments

    International Nuclear Information System (INIS)

    Roberston, S.

    1991-05-01

    The Reversatron RFP is usually operated with toroidal field windings which are a continuous helix of 144 turns. These windings produce a poloidal current which is uniform around the torus. The distribution of current is fixed by the geometry so that the applied field has only an m = 0, n = 0 component. The windings cannot act to stabilize an m = 0 mode with |n| > 0 or any m = 1 mode because these modes will excite no current in the windings. It has recently been suggested that parallel connected field coils might act as a shell by forcing the flux within each winding to be the same. Coils connected in parallel must have the same voltage at their terminals and thus must enclose the same volt-seconds or flux. Data from ZT-40 show that the discharges are more quiescent when parallel or series-parallel connected windings are used

  1. Energy of the field for the field

    International Nuclear Information System (INIS)

    2001-01-01

    Considering the problems that are presented in the field related with the lack of available energy is presented, the Biogas like energy alternative. This is a resulting product of the fermentation anaerobic (without air) of the organic residuals under appropriate conditions of humidity. It is a mixture of gases in which they prevail: Methane (CH 4 ) in a 55 to 70 percent, Dioxide of Carbon (CO 2 ) in a 28 to 43 percent and others as the hydro sulphide by 2 percent. The composition of the biogas depends of: the quality of the used material, of the biodigestor type, of the ambient temperature, of the adopted time of retention. Some of the advantages of the use of this alternative are: better sanitary conditions in the rural means. Decrease in the consumption of inorganic fertilizers. Increase of the agricultural productivity with the employment of the Bio fertilizing (20/25 bigger percent) in comparison with the fresh manure; conservation of natural resources as fuels, fossils and firewood; energy production in the own local consumption. Perfect ecological solution for the obtaining of renewable energy and bio fertilizing

  2. Research and Development Activities in Italy in the Field of Aerospace Structures and Materials,

    Science.gov (United States)

    1979-03-01

    Aerotecnica, Missili e Spazio ” . An extensive historical and critical analysis of such long lasting research cannot be given here; the more recent results are...in the AGARD SMP Program on “ Critically Loaded Hole Technology ” carrying Out Falstaff spectrum fatigue tests on behalf of Italy ,~~ 7. The Un... Metodo degli Elementi Fi— niti — Prestampa n . 5 , IV °Congresso Nazionale A . I . D . A . A . ,M i l a — no ,1977 . 20. Cella Analisi di problein i

  3. Microcanonical quantum field theory

    International Nuclear Information System (INIS)

    Strominger, A.

    1983-01-01

    Euclidean quantum field theory is equivalent to the equilibrium statistical mechanics of classical fields in 4+1 dimensions at temperature h. It is well known in statistical mechanics that the theory of systems at fixed temperature is embedded within the more general and fundamental theory of systems at fixed energy. We therefore develop, in precise analogy, a fixed action (macrocanonical) formulation of quantum field theory. For the case of ordinary renormalizable field theories, we show (with one exception) that the microcanonical is entirely equivalent to the canonical formulation. That is, for some particular fixed value of the total action, the Green's functions of the microcanonical theory are equal, in the bulk limit, to those of the canonical theory. The microcanonical perturbation expansion is developed in some detail for lambdaphi 4 . The particular value of the action for which the two formulations are equivalent can be calculated to all orders in perturbation theory. We prove, using Lehmann's Theorem, that this value is one-half Planck unit per degree of freedom, if fermionic degrees of freedom are counted negatively. This is the 4+1 dimensional analog of the equipartition theorem. The one exception to this is supersymmetric theories. A microcanonical formulation exists if and only if supersymmetry is broken. In statistical mechanics and in field theory there are systems for which the canonical description is pathological, but the microcanonical is not. An example of such a field theory is found in one dimension. A semiclassical expansion of the microcanonical theory is well defined, while an expansion of the canonical theory is hoplessly divergent

  4. Tripolar electric field Structure in guide field magnetic reconnection

    Science.gov (United States)

    Fu, Song; Huang, Shiyong; Zhou, Meng; Ni, Binbin; Deng, Xiaohua

    2018-03-01

    It has been shown that the guide field substantially modifies the structure of the reconnection layer. For instance, the Hall magnetic and electric fields are distorted in guide field reconnection compared to reconnection without guide fields (i.e., anti-parallel reconnection). In this paper, we performed 2.5-D electromagnetic full particle simulation to study the electric field structures in magnetic reconnection under different initial guide fields (Bg). Once the amplitude of a guide field exceeds 0.3 times the asymptotic magnetic field B0, the traditional bipolar Hall electric field is clearly replaced by a tripolar electric field, which consists of a newly emerged electric field and the bipolar Hall electric field. The newly emerged electric field is a convective electric field about one ion inertial length away from the neutral sheet. It arises from the disappearance of the Hall electric field due to the substantial modification of the magnetic field and electric current by the imposed guide field. The peak magnitude of this new electric field increases linearly with the increment of guide field strength. Possible applications of these results to space observations are also discussed.

  5. Tripolar electric field Structure in guide field magnetic reconnection

    Directory of Open Access Journals (Sweden)

    S. Fu

    2018-03-01

    Full Text Available It has been shown that the guide field substantially modifies the structure of the reconnection layer. For instance, the Hall magnetic and electric fields are distorted in guide field reconnection compared to reconnection without guide fields (i.e., anti-parallel reconnection. In this paper, we performed 2.5-D electromagnetic full particle simulation to study the electric field structures in magnetic reconnection under different initial guide fields (Bg. Once the amplitude of a guide field exceeds 0.3 times the asymptotic magnetic field B0, the traditional bipolar Hall electric field is clearly replaced by a tripolar electric field, which consists of a newly emerged electric field and the bipolar Hall electric field. The newly emerged electric field is a convective electric field about one ion inertial length away from the neutral sheet. It arises from the disappearance of the Hall electric field due to the substantial modification of the magnetic field and electric current by the imposed guide field. The peak magnitude of this new electric field increases linearly with the increment of guide field strength. Possible applications of these results to space observations are also discussed.

  6. Quaternionic quantum field theory

    International Nuclear Information System (INIS)

    Adler, S.L.

    1986-01-01

    In this paper the author describes a new kind of quantum mechanics or quantum field theory based on quaternions. Quaternionic quantum mechanics has a Schrodinger equation, a Dirac transformation theory, and a functional integral. Quaternionic quantum mechanics does not seem to have (except in the complex quantum mechanics specialization): A correspondence principle, and beyond this a commuting tensor product, asymptotic states, an S-matrix, a canonical formalism, coherent states or a Euclidean continuation. A new kind of quantum mechanics exists. There are many interesting formal questions to study, which should enable one to decide whether quaternionic quantum field theory is relevant for particle physics

  7. Quantum field theory

    CERN Document Server

    Mandl, Franz

    2010-01-01

    Following on from the successful first (1984) and revised (1993) editions, this extended and revised text is designed as a short and simple introduction to quantum field theory for final year physics students and for postgraduate students beginning research in theoretical and experimental particle physics. The three main objectives of the book are to: Explain the basic physics and formalism of quantum field theory To make the reader proficient in theory calculations using Feynman diagrams To introduce the reader to gauge theories, which play a central role in elementary particle physic

  8. Field studies courses open

    Science.gov (United States)

    Fourteen month-long courses combining applied academics with training in field research methodology are being offered this summer by the School for Field Studies. The courses, held in eight countries during May, June, July, and August, provide unique opportunities for participants to work as a team under primitive conditions.‘Our courses bind together the academic challenge of the research problem, the physical challenge of the site itself, and the interpersonal challenge of the expedition team in a dynamic way so that both cognitive and affective learning are accelerated,’ according to Jim Elder, the school's director.

  9. WORKSHOP: Thermal field theory

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1989-04-15

    The early history of the Universe is a crucial testing ground for theories of elementary particles. Speculative ideas about the constituents of matter and their interactions are reinforced if they are consistent with what we suppose happened near the beginning of time and discarded if they are not. The cosmological consequences of these theories are usually deduced using a general statistical approach called thermal field theory. Thus, 75 physicists from thirteen countries met in Cleveland, Ohio, last October for the first 'Workshop on Thermal Field Theories and their Applications'.

  10. Gauge field theories

    International Nuclear Information System (INIS)

    Pokorski, S.

    1987-01-01

    Quantum field theory forms the present theoretical framework for the understanding of the fundamental interactions of particle physics. This book examines gauge theories and their symmetries with an emphasis on their physical and technical aspects. The author discusses field-theoretical techniques and encourages the reader to perform many of the calculations presented. This book includes a brief introduction to perturbation theory, the renormalization programme, and the use of the renormalization group equation. Several topics of current research interest are covered, including chiral symmetry and its breaking, anomalies, and low energy effective lagrangians and some basics of supersymmetry

  11. Finite temperature field theory

    CERN Document Server

    Das, Ashok

    1997-01-01

    This book discusses all three formalisms used in the study of finite temperature field theory, namely the imaginary time formalism, the closed time formalism and thermofield dynamics. Applications of the formalisms are worked out in detail. Gauge field theories and symmetry restoration at finite temperature are among the practical examples discussed in depth. The question of gauge dependence of the effective potential and the Nielsen identities are explained. The nonrestoration of some symmetries at high temperature (such as supersymmetry) and theories on nonsimply connected space-times are al

  12. Interpolating string field theories

    International Nuclear Information System (INIS)

    Zwiebach, B.

    1992-01-01

    This paper reports that a minimal area problem imposing different length conditions on open and closed curves is shown to define a one-parameter family of covariant open-closed quantum string field theories. These interpolate from a recently proposed factorizable open-closed theory up to an extended version of Witten's open string field theory capable of incorporating on shell closed strings. The string diagrams of the latter define a new decomposition of the moduli spaces of Riemann surfaces with punctures and boundaries based on quadratic differentials with both first order and second order poles

  13. Gela offshore field

    Energy Technology Data Exchange (ETDEWEB)

    Pagliughi, G

    1965-06-01

    The field of Gela, off the southern shore of Sicily, is the only producing offshore field in the Mediterranean. It produces from Triassic dolimite limestones of 434-m thickness, water level at -3517 m. It is a water-drive reservoir producing 10/sup 0/F API oil and has 79 wells, some of them on shore. Most offshore wells are directional wells from shore; there are also 2 fixed platforms and a special mobile platform. The wells are on pump (stroke, 72 in.; capacity 200 tons per day). The crude goes directly to a combination refinery-petrochemical complex at Gela.

  14. DSM-5 field survey

    DEFF Research Database (Denmark)

    Lochner, Christine; Grant, Jon E; Odlaug, Brian Lawrence

    2012-01-01

    Pathologic skin picking (skin picking disorder [SPD]) is a prevalent and disabling condition, which has received increasing study. It is timely to consider including SPD in DSM-5. The aim of this field survey was to investigate possible diagnostic criteria for SPD.......Pathologic skin picking (skin picking disorder [SPD]) is a prevalent and disabling condition, which has received increasing study. It is timely to consider including SPD in DSM-5. The aim of this field survey was to investigate possible diagnostic criteria for SPD....

  15. Finite quantum field theories

    International Nuclear Information System (INIS)

    Lucha, W.; Neufeld, H.

    1986-01-01

    We investigate the relation between finiteness of a four-dimensional quantum field theory and global supersymmetry. To this end we consider the most general quantum field theory and analyse the finiteness conditions resulting from the requirement of the absence of divergent contributions to the renormalizations of the parameters of the theory. In addition to the gauge bosons, both fermions and scalar bosons turn out to be a necessary ingredient in a non-trivial finite gauge theory. In all cases discussed, the supersymmetric theory restricted by two well-known constraints on the dimensionless couplings proves to be the unique solution of the finiteness conditions. (Author)

  16. On vector fields having properties of Reeb fields

    OpenAIRE

    Hajduk, Boguslaw; Walczak, Rafal

    2011-01-01

    We study constructions of vector fields with properties which are characteristic to Reeb vector fields of contact forms. In particular, we prove that all closed oriented odd-dimensional manifold have geodesible vector fields.

  17. Electromagnetic fields and their impacts

    Science.gov (United States)

    Prša, M. A.; Kasaš-Lažetić, K. K.

    2018-01-01

    The main goal of this paper is to briefly recall some different electromagnetic field definitions, some macroscopic sources of electromagnetic fields, electromagnetic fields classification regarding time dependences, and the ways of field determination in concrete cases. After that, all the mechanisms of interaction between electromagnetic field and substance, on atomic level, are described in details. Interaction between substance and electric field is investigated separately from the substance and magnetic field interaction. It is demonstrated that, in all cases of the unique electromagnetic field, total interaction can be treated as a superposition of two separated interactions. Finally, the main electromagnetic fields surrounding us is cited and discussed.

  18. Tripolar electric field Structure in guide field magnetic reconnection

    OpenAIRE

    S. Fu; S. Huang; M. Zhou; B. Ni; X. Deng

    2018-01-01

    It has been shown that the guide field substantially modifies the structure of the reconnection layer. For instance, the Hall magnetic and electric fields are distorted in guide field reconnection compared to reconnection without guide fields (i.e., anti-parallel reconnection). In this paper, we performed 2.5-D electromagnetic full particle simulation to study the electric field structures in magnetic reconnection under different initial guide fields (Bg). Once the amplit...

  19. Electromagnetic Fields and Cancer

    Science.gov (United States)

    ... and magnetic fields (1 Hz to 100 kHz) . Health Physics 2010; 99(6):818-36. doi: 10.1097/ ... and health: review of current status of research. Health Physics 2013; 105(6):561-75. [PubMed Abstract] AGNIR. ...

  20. Ultrasonogram in obstetric field

    International Nuclear Information System (INIS)

    Joo, K. B.; Song, C. H.; Lee, H. B.

    1980-01-01

    The clinical evaluation of 535 cases of sonogram from Mar. 1, 1979 to Oct. 30, 1979 in obstetric field at Department of Radiology and Ob. and Gy. Eul-Ji General Hospital. We present these cases: normal pregnancy, missed abortion, twin pregnancy, hydatidiform mole and ectopic pregnancy, with brief review of literature.